Understanding all the Different Image File Formats

By: Kav Dadfar

When you take a photograph, what is essentially happening is that the camera is capturing data, which creates a digital image. There are many different types of file formats, which can be retrieved and edited using a photo editing software. The most commonly used ones are:

JPEG (Joint Photographic Experts Group) TIFF (Tagged Image File Format) RAW DNG (Digital Negative Format)

PNG (Portable Network Graphics) GIF (Graphics Interchange Format) BMP (Bitmap) PSD (Photoshop Document)

Choosing the right file format is important, and can be critical depending on the level of quality, and also the level of post-processing you intend to do. Here are the pros and cons of using each different image file format.

JPEG

This is probably the best known of all image file formats, and what the majority of digital cameras provide as a digital output from a camera. The thing that you should remember is that JPEG files are compressed quickly in the camera, and thus result in a loss of detail and quality. They are essentially set up to store as many images on the memory card as possible. Some cameras will have options for different quality levels of JPEG (e.g., low, medium, and high). This basically means that the better the quality that you require, the less compression the camera will perform on the original photograph.
Generally speaking JPEGs should be used:

• When the photos are for personal use, for social media, albums, and small prints and not intended for large size prints
• When you don’t intend to enhance or edit the photos much in post-production (e.g., using Photoshop)
• For sharing images via email (without the intention of large size prints)

Benefits (pros)

• Small file sizes means more can be stored on a memory card
• Quicker file transfer times, due to smaller file size

Negatives (cons)

• Loss of quality due to image compression
• Less opportunity for image manipulation in photo editing software

TIFF

This is the most commonly used industry-standard file format, and is generally what print or publishers ask for. Even if the end file format required is a JPEG, the initial captured file would be TIFF. These file formats are usually uncompressed, and as a result offer the opportunity for extensive post-processing. Due to the fact that they are uncompressed, they are also much bigger files, so will take much more space both on your memory cards and also for storage on your computer. Some cameras offer TIFF as the highest image quality level in camera.

Benefits

• Ability to manipulate photos extensively in photo editing software
• Option to print at the highest quality and at much larger sizes

Negatives

• Much bigger file sizes (more storage needed)
• Longer transfer and loading times due to file size

RAW

RAW files are generally available on advanced compact cameras and DSLRs and quite simply put; it is the best option if you want to get the absolute best file from your camera – this is the option preferred by professional photographers. The problem with not using raw files is that your camera will make adjustments, which are permanently embedded into your photos.
Raw files are compressed using a process that retains all of the information originally captured. This means that adjustments such as white balance, exposure, contrast, saturation, sharpness can all be altered in an image editing software, after the image has been taken. Photographing in raw format will require plenty of memory cards, not to mention considerable post-processing time. It will also require some basic knowledge of image editing software such as Adobe Lightroom or Photoshop, as files will have to be edited and converted before they can be used (to share online, print, send to friends, etc.).

Benefits

• The best quality image file is captured
• Extensive options in post-processing and image manipulation

Negatives

• Time needed to convert and edit photos (you must edit raw files)
• Bigger file sizes mean more storage needed and longer post-processing times

DNG (Digital Negative)

Just about every camera these days uses a different proprietary format to capture raw files. Even cameras from the same manufacturer will often use different formats, which means image editing software must to be able read files from all of these different cameras and formats. As a result, the challenge that photo editing software providers face, is how to manage and continuously provide updates for their software to be able to read all the different camera formats.
Enter the DNG. This file format, created by Adobe, is an attempt to create a standard raw file format across all manufacturers and cameras. This is offered as a main raw file format, or as an alternative to the manufacturer’s native raw format. One of the problems with keeping images in their original raw format is that in years to come you may be unable to access them, as they are specific to that camera and manufacturer. But using an Adobe DNG Convertor means you can also store your raw files as DNG files for maximum future security. This does add another step in the post-processing workflow, which means more time is required. However, using image-processing software, such as Lightroom, can help in converting large batches of files so that it doesn’t have to be done manually.

Benefits

• Ability to use image processing software such as Lightroom and Photoshop
• Possibly safer option long term, to guard against inability to open or access files in future

Negatives

• Extra time needed to convert camera raw files to DNG (if your camera does not have the option to supply files in this format)

PNG

Designed in the 90s as an improvement for GIF file format, PNG files are ideal for use on the internet. The strength of PNGs are that they are compressed in a lossless format, and so retain all the digital detail. But unlike other file formats, that quality doesn’t mean big file sizes, which are not useful on the internet where you need pages to be loaded quickly. The other benefit of PNG files are that they allow for partial (effects like drop shadows) or total transparency which is ideal for overlays or logos.
Benefits

• Lossless compression means good image quality, which isn’t compromised when editing
• The ability to maintain transparency, which is ideal for things like overlays or logos

Negatives

• Quality will not be good enough for printing at any size

GIF

Like PNGs, GIF files are ideal for use on the internet. Lossless compression means image quality is not sacrificed, and like PNGs they also offer the ability to maintain transparency (but can’t support partial transparency) and also allow for animation. However, the limitation of GIF files are that they can only contain a maximum of 256 colours, and therefore are not the best choice for photos, but rather images with a limited colour palette.
Benefits

• Small file sizes makes these ideal for use on the web
• Files can contain animation

Negatives

• Limited colours means it is not the best choice for photos
• Does not support partial transparency like drop shadows

BMP

Another lossless file format, BMP was invented by Microsoft, initially for use on the Windows platform but is now recognized by programs on Macs as well. BMPs are large file sizes as colour data is saved in each individual pixel in the image without any compression. As a result this provides a high quality digital file, which is great for use in print, but not ideal for web usage.
 Benefits

• Can be used for printing as images are saved in high quality format

Negatives

• Large file sizes means a lot of storage is required

PSD

This file type is what Adobe Photoshop uses as a default to save data. The big advantage of PSD files are that it allows for manipulation on specific individual layers, rather than on the main image itself. This makes it absolutely essential for any sort of extensive manipulation of the original photograph – such as retouching. This gives far greater flexibility and the ability to fine tune an image as layers can be added, removed or edited at any time without any effect on the original photo (as long as all editing has been done on layers) or other layers. But remember that once a layered PSD file is flattened (this process essentially merges all of the layers) it can’t be undone, so make sure you save your file as a PSD file before flattening.
 Benefits

• Ability to manipulate the image extensively on separate layers
• Once the image is ready it can be re-saved as any other file format

Negatives

• Layered files can be incredibly large in size due all of the additional data stored

These are the most common file types used. Professional photographers generally capture in raw format (even if the final file needed is JPEG), convert those files to DNG, then edit in photo editing software such as Photoshop or Lightroom. But as you can see choosing the right file format to capture the original photo and subsequently save it as is imperative.
Do you use any other file formats? What image editing software do you use? Share your tips and comments below.

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Tips for Choosing Between RAW Versus JPEG File Format

By: Karthika Gupta  

Perhaps one of the most commonly asked questions in digital photography is around which file type to use when shooting – JPEG or RAW file format. Don’t worry if you don’t know much about these two formats or whether your camera supports them. My goal, by the end of this article, is to help you understand what these two types are and help you pick the one that is right for you.

RAW Versus JPEG File Format

At the very basic level, both JPEG and RAW are types of files that the camera produces as its output. Most of the newer cameras today have both these options along with a few others like M-RAW, S-RAW, Large format JPEG, Small format JPEG, etc. – all of which determines the size of the final output file.
The easiest way to see which file formats are supported by your camera is to review your camera user manual – look for a section on file formats. Or you can go through the menu options of your camera and select Quality (for Nikon) or Image Quality (Canon) to select the file format.
Each file format has its advantages and disadvantages so choose the right option that works best for you. JPEGs are, in reality, RAW files that are processed in camera and compressed into that format. Some of the decisions the camera makes in processing the image may be difficult to change later, but the JPEG file sizes tend to be much smaller. 
Let’s look at the advantages and disadvantages of both these file formats in greater detail.

Advantages of shooting RAW files

• It is easier to correct exposure mistakes with RAW files than with JPEGs and overexposed highlights can sometimes be rescued. For people like me who tend to always photograph at least 1/2 stop to 1 stop overexposed (based on my style of photography), this is really beneficial in saving many great images in post-production.
• The higher dynamic range means better ability to preserve both highlights and shadow details in a high contrast scene when the image is being recorded.
• White Balance corrections are easier to make.
• Decisions about sharpening, contrast, and saturation can be deferred until the image is processed on the computer.
• All the original image data is preserved. In fact, when RAW files are opened in post-production software like Lightroom, a virtual copy is made and used. Edits are made in a non-destructive format so the original RAW file is always available for changes at a later stage. This is very useful when you want to edit images in different ways at different times in your photographic career.

Left is the RAW file straight out of the camera. On the right is the finished edited image from the 

same file.

The image on the left (above) was completely blown out because I was in the car and did not have any of my settings correct. But because I photographed in RAW I was able to salvage so much detail in the image. This would not have been possible with a JPG file.

An image that was not properly exposed but photographed in RAW.

The edited image that was corrected in post-processing for exposure issues.

Disadvantages of RAW files

• RAW files tend to be much larger in size compared to JPEGs thereby requiring more storage, not just in camera but also on external storage devices or your computer hard drives.
• RAW images take longer to write to your memory card which means shorter bursts of continuous shooting. For example, my Canon 5D MIII can write about 12 RAW files continuously and about 30+ JPEG files in the continuous (burst) shooting mode. Check your camera manual for specifics around your own camera’s burst mode (a.k.a continuous photography mode).
• Not all programs can read RAW files. This used to be an issue, but now there are lots of great programs that can work directly with Raw files such as Adobe Lightroom, Canon’s Camera RAW, Luminar, On1 Raw, ACDSee Photo Studio Ultimate, and other such programs.

Advantages of shooting JPEGs

• JPEG files are much smaller in size compared to RAW files and hence need less storage space – both in camera memory and on your computer hard drives.
• JPEG images write to disk more quickly which means longer bursts of continuous shooting opportunities especially during wildlife photography, fast action sports, or even dealing with little kids that are always on the move.
• These JPEG files can be instantly viewed with many programs including common web browsers, powerpoint, and other such common applications.

Disadvantages of JPEG files

• It is harder to fix exposure mistakes in post-production with JPEG files.
• JPEG files tend to have a smaller dynamic range of information that is stored and this often means less ability to preserve both highlights and shadow details in the image.
• White Balance corrections are more difficult with JPEG files.
• Decisions about sharpness, contrast, and saturation are set in the camera itself and in most cases, these are difficult to change later in post-production without destroying the image quality.
• Since a JPEG image is essentially a RAW image compressed in-camera, the camera’s computer makes decisions on what data to retain and which to toss out when compressing the file.

The same image when edited as a JPEG for exposure issues becomes a lot grainier than an 

underexposed RAW image. You cannot pull them as far as a RAW file.

Another old-school way to think about these two file types is as slides and negatives. JPEGs are like slides or transparencies and RAW files are like negatives. With JPEGs, most of the decisions about how the image will look are made before the shutter is pressed and there are fewer options for changes later. But RAW files almost always require further processing and adjustments – just like negatives.

Which format to choose?

Now that you understand the difference between RAW and JPEG images, deciding which one to use is dependent on a few different factors.

• Do you want to spend time in post-processing your images to your taste and photography style?
• Are there any issues with limited space on your camera’s memory card and/or computer hard drives?
• Do you have software and/or editing programs that will read RAW files easily?
• Do you intend to print your images or even share images online in a professional capacity?

Some photographers are intimidated by RAW images. I was as well when I had just gotten started in photography because I did not know the true power of a RAW image. However, once I started photographing in RAW there was no going back.
Even everyday snapshots are shot in RAW now because of the great flexibility I have in correcting any mistakes that I make. One of the most common mistakes that many photographers make is around image exposure and that is relatively easy to fix with RAW files. 

I accidentally overexposed the setting sun and lost some of that golden warmth hitting the tree.

One of my favorite San Francisco cityscapes at sunset. I accidentally overexposed and lost the sun 

flare but was able to edit it and bring back that sunset warmth in post-production because it is a 

RAW file.

It’s getting easier to use RAW files

Traditionally the two main issues with RAW files seem to be fading every day:

1. The cost of memory to store or backup these RAW files is getting cheaper and cheaper by the day.
2. Software that can read RAW files is more readily available. In fact, there is even inexpensive and free software that can read these RAW files now.

There is still the issue of write speed for your camera. If you focus on fast-moving subjects like wildlife or sports photography then perhaps write speed is a key factor in deciding whether to photograph in RAW versus JPEG. So for fast moving objects and/or wildlife and birding photos, JPEG may be a better choice.
Another thing to note is that most of the newer cameras have the ability to capture both JPEG and RAW images at the same time. But this takes up even more storage space and might not be the best use of memory. You are better off just picking one option and sticking with that.

Waterfall images using a slow shutter speed tend to blow out the background but editing a RAW 

image in Lightroom helps bring back some of the highlights.

I hope this was helpful in not only understanding the differences between RAW versus JPEG file formats but also in helping you decide which one to choose and why. So tell me, do you belong to the RAW or the JPEG camp?!

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How All JPEG Images are Cobbled at Birth

By: Herb Paynter

Everybody knows that JPEG images are prone to compression artifacts. Meaning every time an image is opened (whether altered or not) and re-saved, the tonal structure of the photo is recompressed using the same destructive process. File recompression always causes additional detail to be lost. Every time a JPEG image is adjusted in any way, those original 256 levels of color are redistributed and detail is lost.

JPEG files offer various levels of file compression and repeated editing and saving causes further 

degradation.

But, that’s the least of the JPEG limitations.
First of all, JPEG is an old format originally designed for a long-past era. A group of photographic experts (Joint Photographic Experts Group) was assembled in 1986 for the single purpose of whittling down very large image file sizes:

1. To display on old CRT (Cathode Ray Tube) computer monitors – basically old TV sets without the channel tuners
2. To travel efficiently over the fledgling (slow) Internet, which was designed to accommodate the best broadcast television standards
3. In order to compress them for size and portability. The first JPEG specification was released in 1992 and ratified again in 1994.

Now over 25 years later, the same format is still in use!

The Price of the Program

Many elements of a digital image get altered with JPEG file compression. True, massive amounts of disk real estate get saved in the process but significant other parts of the image get thrown away.
First, the full RGB signal is converted to an abbreviated color space used for analog TV, called YCbCr. CRT displays are driven by red, green, and blue voltage signals, but storing RGB signals involves redundant data. While most of the luminance (brightness) information (Y channel) is retained, the two color channels (red and blue) are significantly reduced in scope.

Highlights clipped in the JPEG process are still present in the RAW file.

An original RGB camera image (TIFF, PSD) contains massive levels of color; many of which the human eye cannot distinguish. Since the end goal of JPEG is zero-body-fat, once a base interpretation of the image is defined, and the 256 colors identified, almost all the “extra” colors are removed, leaving a mere skeleton of the color range.
Colors are characterized as bit depth; the number of tiny measured steps between full color and no color. Humans can only perceive 200 levels of each color under ideal lighting.

The Problem

The decision on what colors get eliminated is pre-designated by a cookie cutter JPEG template, rather than by the human evaluation of each image’s tonal structure. JPEG restricts the color for all images indiscriminately. One template fits all. Excess information is discarded.
Basically, JPEG compression is like weight loss by body part elimination rather than fat reduction; more of an amputation than a diet. As I’ll explain later, the production of a JPEG file is the ideal final format, but not the most ideal for image editing.
JPEG makes use of a basic human sight limitation. We can see tonality more than we identify individual colors. This is why we see only shapes in low lighting conditions. Basic luminosity is retained with JPEGs but much of the color is down-sampled.
The next multistage high-math transformations in this process get mind-boggling very quickly, so let’s just say that some very intricate 8×8 pixel matrix calculations take place based on the limitations of visual perception. True optical illusionary voodoo is at work to further reduce the “weight” of each image. The vulnerability in this mass weight loss program is that JPEG colors are weakest in the highlights and can display nasty artifacts when the images are re-saved. All those compression calculations take place again when JPEG images are re-saved.

The basis of JPEG compression involves a complicated formulation involving blocks of 8 pixels. The 

values of each block are quantized and distilled into similar colors to eliminate color variations that 

the human eye has trouble distinguishing.

JPEG files typically reduce the size 90% from the original PSD or TIFF file with little perceptible loss in image quality, as long as the file remains unchanged in size and content. Images that contain significant areas of similar tones (skies, building surfaces, etc.) benefit most from this file compression format.

Quantization

This JPEG standard is not an image resolution issue as much as it is a color depth issue. The number of pixels is not reduced, but the number of colors is. The “pixelated” appearance is not caused by a reduced number of pixels, but a reduction of the color quality of those pixels. The visible loss comes from changes to the initial 8×8 pixel matrix when the edited file is re-saved.
In 1992 it was unthinkable to produce images at a higher quality than TVs could broadcast, including the 256-tone limitation and the sRGB color gamut. In 1992, this was state-of-the-art stuff and it served the industry well for many years.

14-bit sensors can capture 16,000 levels of color in each RGB channel.

But then Silicon Valley developed camera image sensors and processors that could handle more than 8-bit images. That meant that digital manufacturers began building cameras whose images contained twice the level of color (10-bits, or 1000 levels of color).
Next, “deep-bit” images were accommodated by Adobe within Photoshop which changed everything. Much larger color spaces were developed to support this newly expanded color depth. (Keep in mind that bit depth is simply a way of dividing an image’s range into much smaller steps between zero color and full color of a pixel).

Deep (Color) Space

My friend Bruce Fraser (the father of color management) worked with Adobe to formulate what we know as Adobe RGB. Later a larger color space was developed called ColorMatch RGB. Even later, an even larger color space was developed and was labeled ProPhoto RGB. All three of these color spaces exceed the 256-level limitation of JPEG.
But even if an image is edited in one of these larger color spaces, when it is saved as a JPEG, it is automatically reduced to 8-bits (256-levels) per channel.

Bit depth is the measure of tones between full color and no color. JPEG images affect the image bit 

depth, not the image resolution, as commonly believed. Each time a JPEG file is re-saved, the color 

loss increases and the image clarity decreases.

Camera JPEGs

Camera-saved JPEG files are “shaped” by the camera settings in place when the image is captured. The algorithm applied to the image data harvested by the image sensor reflects the color model (sRGB, Adobe RGB, and ProPhoto RGB), sharpening preferences, etc.
A word about compression. Compression is probably not as accurate a term to describe JPEG limitations as it could be. Compression sounds like what your Aunt Martha does when she uses a girdle to compress herself into a smaller “container,” but that’s a totally different thing. When she is decompressed, all of Aunt Martha is still there.
JPEG uses “lossy” compression, which really means that some parts were discarded (or lopped off) for good. Aunt Martha only wishes her girdle would help her permanently “lose” something.
Think of image compression more like an abbreviation. When a JPEG file is saved to disk, the data captured by the camera’s image sensor gets compressed into a general mold, dictated by the color settings in the camera when the picture is taken.

Photo Finished

This JPEG process effectively plays the premature role of photofinisher, stamping out its own interpretation of the scene. What started out as a 4000-16,000 level per color image gets reduced to a 256-level picture with just a skeleton of color, leaving precious little room for tone (or color) adjustments.

Both dark and light tones were clipped by the JPEG template but recovered from the RAW file.

JPEG limitations of 256 levels often clip brighter tones to white and darker tones to black prematurely 

(top grayscale above). RAW images allow the user to recover details that appear lost 

(bottom grayscale).

If the camera settings were not perfectly set to capture the brightness (bit depth) and contrast (tonal range) of the existing scene, the JPEG-rendered the photo leaves little room for recovery.
In the end, every image will be reduced to a 256-level file before it is either shared publicly or produced as a print. That’s just the nature of photography. There are very few printing devices that can reproduce more than 256 levels of color, and even if they could, the human eye couldn’t see those extra colors anyhow.

While digital cameras can capture up to trillions of colors, human eyesight recognizes less than 200 

individual red, green, and blue colors.

JPEG Sufficiency?

So if we can’t see more than 200 different levels of each color (and JPEG provides 256), why do we need the billions captured as RAW files? Simple answer… those excess levels provide ample elbow room to push color levels and saturation into the most visually ideal 256 tones for printers to print and humans to observe. It’s all about optimizing detail.

The dynamic range of the beach scene exceeded the JPEG “template” and highlight detail appeared 

to be lost (left) but was retained in the RAW file (right).

So what can we take away from this?
First, JPEG is the most basic of photo file formats and is only ideal (as a camera file) when ALL the pre-capture lighting factors match the current camera settings. Second, it’s always best to set your camera to record both hi-level JPEG and RAW files as an insurance policy. And third, the unabridged image data saved as a RAW file enables the final JPEG to be shaped (as close as possible) to what your mind perceived when you clicked the shutter button.
JPEG is the digital file format you want to end up with but it is not always the one you want to start with. There is a waste factor involved in every manufacturing process, and digital imaging is no exception. It’s better to have too much than too little. Always start with more than you need.
Intend to lose the weight, but do it on your schedule.

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Camera Color Spaces Explained – sRGB vs Adobe RGB vs RAW

By: Herb Paynter 


Your camera is probably able to capture color images in a variety of different color containers called “spaces.” These camera color spaces collect colors in one of several size light buckets labeled sRGB, AdobeRGB, and RAW.
Each bucket gathers slightly increased varieties of light, similar to the way Crayola crayons are packaged and sold in increasingly inclusive collections of colors; small, large, and jumbo.
Camera color spaces offer photographers a variety of different size boxes.

Camera color spaces

Scenes that include both brilliant colors and bright lighting are excellent candidates for capture with 

AdobeRGB color space.
F/3.5, 1/1000, ISO 400, Lumix G Vario 2.8, 35mm

A debate in the photo community usually arises over which camera color spaces to choose in the camera’s preferences. Some color spaces capture more of the hues and saturated colors than others. Pictures captured in one space may include more colors than another.
Each space is ideally suited for certain purposes, and the question of which camera color space to choose needs a bit of explanation. In addition to the capture question, choosing a color space for post-production editing will depend on the image’s ultimate usage.
Your camera’s color spaces involve not just color data, but additional parking space on the drive. Larger color spaces provide more bit-depth (explained below), which occupies more digital real estate on the memory card. So, the choice of which to use does have practical importance.

What camera color space to use

There is no singularly perfect color space choice, so let’s examine which is best for specific situations.

Images that do not include highly-saturated color but contain significant detail in the shadow areas 

will benefit from RAW format capture and high-bit processing. F/10, 1/1600, ISO 800, Lumix G 

Vario 2.8, 200mm

Unless the sole purpose of a photo is to display as a high-resolution digital image, you might want to convert the file’s original color space for a less demanding result. However, keep in mind that every time a file mutates from a larger color space to a smaller color space (RAW to AdobeRGB, or AdobeRGB to sRGB), the image’s color intensity and integrity may diminish in the process. Some imaging applications are less demanding than others.
While copies of digital files remain identical in size and intensity to the original regardless of how many times they have been copied, when a digital file mutates to a lesser color space, it will always lose some critical color information. Your camera color spaces in general, and device color spaces, in particular, are all unique. Each serves a particular purpose.

The extreme dynamic range and saturated skies benefitted from the RAW capture and editing in 

AdobeRGB. Detail buried in the shadows was possible because of the 14-bit capture. F/14, 1/300, 

ISO 3200, Lumix G Vario 2.8, 12mm

It’s a matter of depth

The difference between camera color spaces boils down to an issue called bit depth. Bit depth is a mathematical description of how many visible distinctions between shades of color can be recognized and reproduced by different devices (a techie term for scanners, cameras, computer monitors, and printing machines). Unfortunately, not all devices can reproduce all colors the same (which is the primary stumbling block amidst all color issues).
Every device reads and reproduces color using a different process. While this sounds like a fixable problem, there is a sad and unsolvable reality behind the problem. There are at least three different interpretations of color at play in every capture-display-print cycle.

These colorful seat cushions and deep shadows were captured in RAW format, edited in AdobeRGB, 

and saved in sRGB for upload to our camera club’s server for display as part of a club field trip 

slideshow. F/7.1, 1/320, ISO 400, Lumix G Vario 2.8, 19mm

First, cameras capture color by recording intensities of light as electrical signals and interpreting those signals as colors. Each color is assigned a specific number.
Second, these numbers are then sent to the computer. Here, they get translated into another process that interprets those electrical signals into a process that turns on tiny lights (called pixels) on a backlit screen.
And third, those pixels are then sent to a printing machine that instructs those pixel values to spit tiny splatters of colored ink onto paper.
It’s a very complicated process that color scientists have tried for years to make simple. Unfortunately, it just ain’t that simple!
Anyway, during this hair-on-fire digital transition, different methods are employed that utilize the various color spaces in a way that transforms the colors from one device to another as accurately as possible. Sometimes the color translations don’t convey the colors as accurately as we would like, which is why sometimes the monitor colors don’t match the printer colors.

Science uses charts like this to plot the characteristics of camera color spaces. While these charts are 

referred to as “theoretical” because they are not visible to the human eye but represent what each 

color “bucket” can capture versus what the eye can see.

The ultimate referee

The only comprehensive color space that plots the full scope of what the human eye can see is what the science community calls L*a*b* (inverted horseshoe diagram) space.
The human eye is the ultimate arbitrator in the color wars, and all device capabilities (camera, display, and printer) are defined by how they match up to the eye’s master gamut. This is why this strange horseshoe shape is referred to as the Reference Space. All other devices, whether camera, display, or printer, can only recognize and utilize portions of this “reference space,” and they usually disagree with each other.
Color is a very diverse and dysfunctional family. Each device speaks a different dialect of a similar language. Each produces colors that cannot be faithfully reproduced on other devices. Color is a very messy topic.

Crayola crayon boxes contain varying numbers of colors just as color spaces collect varying amounts 

of color. The lightest and darkest color crayons are the same value, but larger boxes contain more 

colors than smaller ones.

Some devices can express color more completely than others. Unfortunately, no device created by humans can reproduce all the colors that can be seen by humans. Also, the colors captured by one device that fall outside the gamut (Crayola box size) of other devices, get clipped, lost, or compressed during the handoff. Those colors never come back home.
This is the tragic truth about digital color reproduction. The trick to color reproduction is in retaining as much of the common color as possible during the process. Fortunately, this same human eye (and brain) are very forgiving about accepting the limitations of non-human devices.
Color reproduction is a true application of the law of diminishing returns and the visual science of physics. Photographers understand this law quite well.
Very rarely can a camera actually capture all the color and dynamics of an original scene. Moreover, nature’s color gamut extends even further than the colors that the human eye can identify. Any time a digital image gets transposed from one form into any another form, that transformation is a diminished-value exchange.
As an image is transferred from one device to another, those pixel values located outside the color gamut of the destination device always get lost in the translation. The object of color management is to mitigate color loss and maintain as much of the appearance of the original as possible, all the way through the reproduction process.

RGB spaces (sRGB, AdobeRGB, ProPhoto RGB)

It all begins with the camera’s color settings that are in place when you capture the scene. All cameras capture light through red, green, and blue filters (RGB color space). While there are a number of RGB color spaces to choose from, each sports a slightly different color gamut.

Each device in the photography chain interprets colors slightly differently, and each responds to the 

individual color spaces uniquely.

Each color space (sRGB, AdobeRGB, ProPhoto RGB, etc.) provides a unique collection of color attributes, and each space satisfies specific display and reproduction requirements.
Gamuts are descriptions of the range of colors that a device can recognize, record, display, or print.
Shooting a vibrant, saturated scene with the camera requires a larger color space. Using a camera color space with a smaller gamut could significantly diminish the raw, harsh emotion of the scene. This is why most photography experts encourage photographers to set their cameras to capture images in AdobeRGB.

sRGB

Almost all digital cameras are factory-set to capture colors using sRGB as the default color space for a plausible reason; most of the pictures we take never get printed! At best, we view them on computer monitors or social media. Quite honestly, most of the pictures we capture never make it past the initial glance at the camera’s LCD screen. Capturing those images in higher-bit color space is a total waste of disk space.

sRGB color space remains largely unchanged since it was defined in the 1950s to compress video 

images into a manageable size for broadcast. While the format has been updated slightly, the basic 

intent is the same.

sRGB was developed by HP, Microsoft (and others) back in the early days of television to address the color gamut needs of most televisions (early versions of computer monitors), and the standard was set long ago. The airwaves and Internet browsers live on an sRGB diet. As such, the sRGB color space standardizes the way images are still viewed on monitors and televisions.

Adobe RGB

If the ultimate destination for your picture is monitor or display-based presence (presentations, Internet, or television displays), this is probably the best choice to capture images. However, if you shoot for print on paper, both AdobeRGB 1998 and ProPhoto RGB RGB contain a wider gamut of colors and are thus more suited for preparing images for print.

The brilliant dynamics and saturated colors are always captured best in the deepest color bucket of 

all – RAW. The degree of adjustments provided by RAW capture and ProPhoto RGB editing is perfect 

for images like this. F/6.3, 1/800, ISO 400, Lumix G Vario 2.8, 26mm

RAW

Actually, the most ideal bucket for capturing images actually exceeds the gamuts of all three of these camera color spaces. I’m speaking of course of your camera’s ability to capture images in RAW format. This is a format that supersedes any defined color spaces.
RAW files capture color in the highest bit depth possible; up to 14-bits per color. RAW is not an acronym; it is more of a description. It is the recording of all the limited color depth and uncompressed dynamic range of the original scene. Start RAW and strip down from there.

Camera color spaces explained – Conclusion

Congratulations on sticking with this article through all the minutia.
By now, it probably seems like camera color space is more like outer space, but it doesn’t have to remain this technical. Simply remember to capture images in RAW format (perhaps in addition to capturing them as JPG) and then transform the colors down the chain of reproduction as the need dictates.
Edit images in the camera color spaces of ProPhoto RGB or AdobeRGB to retain as much color elbow room as necessary. Those images destined for print should be transposed to AdobeRGB, and reduce those images destined for the Internet or slideshows to sRGB. Simple, enough!

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A 15 Minute Lesson For The Photography Beginner

By: Peter West Carey

I was sitting in the heat and humidity of the the Amazonian rainforest inside the 1970’s designed airport at Puerto Maldonado, Peru. We had a few minutes before heading back to Lima and I had been trying to find time to help a young Norwegian traveling on the same itinerary as me.
When he saw my camera a few days earlier, he had the same comment I have head a dozen times while traveling;
“I just bought this camera before my trip and I haven’t a clue how to use it. So I just leave it on Auto.”
If you have uttered this phrase in the recent past, read on. If you have mastery of your camera this post will not likely excite you.
I then told him I’d be happy to help him get a little more out of his camera for the rest of his travels through South America. It’s always tricky making this offer, because some people just want a few tips and some can suck down half a day of sightseeing with constant questions. Unfortunately we didn’t have a chance to sit down and talk cameras until our time traveling together was almost over.
With just 15 minutes until we boarded and sat in different areas of the plane, I did my best to fill his head with quick tips to take better photos while he headed on to Brazil. Here then is what I told him.

Move off of Auto (and the reasons why)

Like a lot of people new to cameras, he was stuck on Auto or Auto with flash off. I quickly explained that his camera takes average pictures in Auto and took a few example shots to show him. Want to pick one person out of a crowd? Chances are Auto will make sure everyone is in focus, losing your friend. Standing in front of a sunset and wondering why your friend is always pitch black and the sun is not bright? Auto mode. With that in mind, I suggested….

Try P mode

Moving the dial to P(rogram), I explained that he would now be in charge of when his flash fired (and to not forget to use it at night when needed, but also in the middle of the day when there are shadows on faces). He could also control metering. As there were skylights in the airport and friends sitting across from us, with a very bright backlight, I took a shot with the friends centered. They were very dark because of the backlight. “Yeah! I’ve done that all the time!” he exclaimed. The camera was metering off the background and not the friends.
I showed him the simple trick of aiming the camera slightly down, so the friends filled the frame more than the backlight. He could then hold the shutter down halfway and it will lock the settings to that metering. Then, panning back up to center the friends, take a shot. Boom, the friends were light enough to be seen while the background got a bit blown out. I explained holding the shutter down half way locks exposure (the overall brightness of the shot) and focus.
P mode would allow him other adjustments, which we skipped over in the interest of time. I left telling him there was more to learn and his manual would explain adjustments that can be made in this mode.

When to use A Mode

A(perture) mode was next and it has one of the coolest effects on images. A mode controls how many things are in focus. Skipping over the technical aspects, I told him the lower the f/ number (shown on the bottom of his screen) the less things are in focus. The higher the number, the more things in focus. This is very important for making things standout.
Again, using a friend, I showed how at f/3.5 the person stood out from the other passengers in the waiting area (demonstrated here with a shot of a ruin wall taken at Machu Picchu shot at f/6.3).

I then spun the front dial on the camera to increase the f/stop number to its maximum. Taking another shot, the friends quickly blended into the background (shown here by increasing the aperture number to f/40 at Machu Picchu).

The lesson? A smaller number for aperture helps make objects stand out from their background. When you want to include everything, like a friend standing in front of a beach or monument, use a higher number.

When to use S mode

As they made the pre-boarding announcement and people started to shift, I sped up my presentation, which, at this point, was now about speed in S(hutter Priority) mode. In S mode he now had control of how much things were blurred. With limited time, I went for two highlights of S mode:

At 1/10th of a second, motion starts to blur in interesting ways if you know what’s going on.

For instance, waterfalls start to get the veil look to them. Any movement can be emphasized, such as this mechanical plow in Bhutan, churning a field.

1/500th of a second is a good shutter speed to start freezing motion.

If he wants to stop something from moving, the faster the shutter speed the better. Fast moving objects typically need a shutter speed of 1/500th of a second or more. This number is also controlled with his front dial, as it will likely be on your camera. An example below of a truck speeding past a newly constructed statue of Buddha in Bhutan, shot at 1/800th of a second to stop the truck sharply.

Get closer

I left him with the last bit of simple advice I leave for you. Get Closer. One of the biggest mistakes new photographers make is moving too far back and trying to get everything in focus. This approach, while sometimes effective, makes images flat and two dimensional as they lack depth. Get Closer. I showed him some examples with his camera and while I don’t have those images in the airport with me, I can show you what I mean with another set of photos.
The first images is the ‘standard’ tourist shot. “Look! It’s a pretty plant!”

The problem is the plant gets lost in the background. Moving a bit closer, it starts to stand out a bit more.

But we can do ever one better by getting some detail. In this last shot, I am about a foot from the plant.

By this point, my section of the plane was being called for boarding and it was time to go.
While I will likely never see the young Norwegian again, I hope those 15 minutes helped him to take a few better photos while on his world travels. It is also my sincere hope that these few minutes can help you if you are just getting started with a new camera and want some easy advice for better photos.
Lastly, I should have added: Experiment! Photography should be fun and with practically zero cost to experiment digitally, play with your camera and see what works for you.

If you had just 15 minutes to help someone new to photography and traveling, what would you tell them?

 

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Using Fill Flash

By: Darren Rowse

I was chatting with a new digital camera owner on the weekend about their camera and they were telling me about how they didn’t think they’d ever use anything but fully automatic mode on their great new Canon DSLR.
They told me that ‘auto’ mode would produce the perfect shot in every scenario – so why would they ever need to use anything else.
I asked them to show me some of the shots that they’d taken on their camera and they allowed me to flick through some shots until I came to this one:

It was taken at a wedding that they attended where the bride, groom and celebrant (I was actually the celebrant – like my pink tie?) were positioned in a fairly dark gothic-like hall in front of a number of large windows.
The Problem
The problem with the shots was that there was so much light coming in the windows that the super little camera that my friend was using in Auto mode thought that the scene had enough light. As a result the window and what you can see through it is reasonably well exposed – but the main subject matter of the picture (the happy couple) are well under exposed. Some of the other shots taken this day were much worse and had the bride and groom as silhouettes.
Obviously the issue with this shot is that there is just not enough light from the front of the subjects to light up the subject with the shutter speed being used.
The Solution
There are a number of possible solutions to this problem but one of the easiest is to override the camera and force it to shoot with a flash – a technique often called ‘fill flash’. Fill Flash is used to supplement existing light in a scene – it’s generally not the primary light source (as a flash often is at night) but fills in light where natural light doesn’t go.


In addition to helping with backlit subjects fill flash helps in more subtle ways also by helping to eliminate shadows cast by facial features (under eyes, noses, chins) or under hats – especially when light is shining down from above. It also might just add a special little sparkle to the eye of the person you’re photographing.
In the same way it is also very useful in other styles of photography including in nature and macro photography for lighting up subjects in much the same way as when you’re photographing people.
Most cameras have a way of doing this that doesn’t mean that you have to go into a full manual mode – in fact my point and shoot digital camera allows me to force the flash to fire IN automatic mode. Check out your digital camera’s owners manual to work out how to do this on your digital camera but in most point and shoot cameras the main button to look for will be the one with the lightning bolt (flash) on or near it. Press this multiple times and it will cycle you through the different options for flash (on, off, automatic, red eye reduction are the main four). Some point and shoot cameras even have a ‘fill flash’ option that ramps back the strength of the flash a little which is ideal.
Some more advanced digital cameras will allow you to experiment with the strength of the flash you use. This will enable you to tailor your flash to the situation you’re in. Most DSLRs will let you pull back your flash output in 1/2 or even 1/3 stops. I find that at the start of a photographic shoot if I shoot off a few shots at different exposure levels and check them on my LCD that I quickly find out what’s working and can stick to that level in the shots that follow.
Keep in mind that Fill Flash can be overdone. If you beef up the flash too much your shots can look artificial and overexposed. Aim for subtlety when using a flash and you’ll really lift your shots.

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7 Strategies for Avoiding Flash Blow Out

By: Darren Rowse 

Last weekend I was at a party with my point and shoot digital camera and wanting to take a few shots to help us all remember the night. The problem was that it was a poorly lit room and I needed to use my flash. The result was a lot of blown out images. The flash was too strong! What should I do next time? – Sally
You’re not alone with this problem Sally – I see a lot of shots suffering from ‘flash blowout’ syndrome, many taken on point and shoot digital cameras. In fact while searching on Flickr for such shots today I found so many – it must be one of the most common problems that people face in their digital photography.
The problem that point and shoot camera owners face when it comes to using flash to light a scene is that many point and shoot cameras offer a photographer much less control over how powerful the flash is and what direction the light is pointed (in comparison to a DSLR with a dedicated flash unit that can be bounced in different directions at different levels).
However don’t resign yourself to flash dominated shots – all is not lost. Below are 7 tips for point and shoot users (and DSLR users wanting to use their camera’s flash).

Learn to See Your Flash as a Secondary Light Source

Before I give some specific tips on decreasing the impact of your flash on your shots let me share a tip that a more experienced and wise photographer once gave me.
A flash should only ever be thought of as a secondary light source. In almost every situation that you will want to photograph there will be some level of existing ambient light. This light is important as it is the natural light of the scene you’re trying to capture. Your flash should be used to supplement existing light rather than as the primary way of lighting a scene. If you use a flash as the primary source of light it will look artificial.
As a result of knowing this you’ll find that most of the following strategies are about making the flash more subtle or making the natural light more noticeable.
OK – so lets get on with some strategies and techniques for Avoiding Flash Blow Out:

1. Take a Step Back

One of the simplest ways to decrease the impact of the light coming from your flash is to put a little more distance between you and your subject. While I generally advise people to get in close to their subject and fill the frame – this can often make the effect of a flash even brighter. Many of the blown out flash shots that I see are simply because the photographer is too close to their subject.
Stepping back further away from your subject doesn’t mean that you can’t fill the frame. You could use your camera’s zoom lens (although this can increase the effect of camera shake) or simply crop the shot later on your computer.

2. Diffuse It

If your digital camera doesn’t allow you to have any control over how much light it outputs (see below for more on this) you might want to consider manually making some changes that limit or diffuse the light coming out of your digital camera. This is something that users of dedicated flash units can do by using specifically made flash diffusers – but point and shoot owners may need to get a little more creative and hack their own solution.
One of the most effective ways of doing this is simply to find some semi opaque material to place over your flash. I’ve seen some point and shoot owners stick a little white tissue paper over their flash and others do this with a little piece of cellotape (the semi-opache kind). Just remember that the color of the material that you use will impact the color of the light that comes out of your flash (and therefore the color cast on the scene) – so white tape or tissue paper will give a more natural light than red or blue!

3. Redirect it

Another strategy that dedicated flash users will often use is to redirect or bouncing the light coming out of their flash off another surface. They are able to do this because these flash units are able to be swiveled and shot into different directions.
Point and Shoot users obviously can’t change the direction that their flash points – but might want to try ‘hacking’ their camera in this way also. I’ve seen a few photographers do this simply by taking a small piece of white card and putting it at an angle in front of the flash so that the flash is redirected up onto the ceiling of the room (or even sideways onto a wall).
This little hack will need some experimentation to get the angle of the card right and the results will vary quite a bit depending upon the situation that you’re photographing (distance to your subject, how high the ceiling is, how much ambient light there is etc). Again, the color of both the card you use as well as the ceiling or wall that you’re bouncing the light off will impact the color cast in the shot.

4. Night Mode

Most point and shoot digital cameras have a fun little option on their mode dial called night mode. This mode tells the camera to use a technique called ‘slow sync flash‘. We’ve talked about this previously here at Digital Photography School – but to put it most simply it means taking a shot with a slower shutter speed while still shooting the flash. This means that you get a little more ambient light from the scene while still freezing the action with the flash (like the shot to the left). The shots taken in this mode won’t give you pin point sharp images – but they can be fun and very effective (particularly if there is some nice colored lights in the room).

5. Decrease Flash Output

Some point and shoot cameras have the ability to tell the camera just how much flash you want it to use. This won’t be something you all have at your finger tips but check your camera’s manual to see if you have it. If you do, dial back your flash output by a stop or two to see what impact it has. It might take a little experimentation to get the setting just right but it can help you end up with much more natural shots.

6. Add Light

This one could get you kicked out of the party – but getting a little more light on the scene is another pretty obvious way to help the situation. At an extreme level this might mean turning on all the lights in the room (and potentially destroying the mode) or it could mean moving your subjects to a better lit position near a lamp or light. I’ve done this in photographing wedding receptions – simply positioning myself in front of an open door that leads into a better lit room where the light spills in lighting up the faces of guests on the dance floor.
Another way to increase the impact of ambient light on a subject is to think about reflective light. For example photographing someone standing next to a white wall as opposed to a black wall will mean that any ambient light in the room will be bounced onto them (this is similar to having your own reflector).

7. ISO, Shutter Speeds and Aperture

One last way to decrease the impact has on a scene is to tweak some of your camera’s exposure settings – particularly those that impact how the camera treats light like ISO, Aperture and Shutter Speed.
This isn’t the place for a detailed explanation of the basics of exposure (see my previous series on getting exposure right in digital photography) but if your camera allows you to change any of these settings they could be helpful. In brief:

• ISO – increase the ISO setting and you increase the camera’s sensitivity to light. This means the ambient light in the room will have more effect and you’ll have less need for flash. Keep in mind that increasing ISO also increases the grain or noise in your shots. Read more on ISO.
• Aperture – as you increase the aperture of your camera you increase the size of the hole in your lens and more light is able to get in quickly. So increasing aperture (this means decreasing the f/number) can be something to experiment with. Keep in mind that this means you also decrease the depth of field in your shot meaning you need to get your focus spot on and that not everything in your shot might be in focus. Read more about Aperture.
• Shutter Speed – lengthening the amount of time that your shutter is open increases the amount of light hitting your image sensor. This is another factor in exposure that you might like to experiment with. Keep in mind that if there is movement in your scene (even small movements) that the longer the shutter is open the more blur you’ll get in your shot. Read more about Shutter Speed.

Please note – not all point and shoot digital cameras have the ability impact all (or any) of these settings. Check your manual – particularly to see if your camera has Aperture or Shutter Speed Priority Modes. I’d personally start with increasing ISO and then switching to a larger Aperture before playing with Shutter Speed (unless it was part of a Slow Sync Flash strategy).

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