Photo.net

Hi  Everybody, thanks for stopping by my blog today.  Like a lot of you I like to learn from other photographers.  There are a lot of great blogs and websites for us to choose from and one of my favorites is Photo.net.  If you've never visited them I hope you'll stop by as a result of reading this post.  It doesn't matter if you're a beginner, or a seasoned professional, you'll find input from Photographers of every experience level.  I especially like their question and response feature.  Here's a sample of what I mean:

metering a perfect black background

ivan vilches , Jul 19, 2014; 11:58 p.m.

hello guys i am experimenting with my camera (fuji gx680 with 180mm 3.2) i am a beginner, always i shoted with my nikon d800 and forget learn a solid base of theory of exposure, my scene is a candles on a nice table and in the background like 1.5 meters is the background , it is black , the only light i have is the candles , how i can know if my background is perfect black? metering with my d800, i know i can do a test shot but i wanna learn about teory , thinking i dont have the digital camera and it is a spot meter for example, the background have a slight light for the candles is any way to know if will be black in terms of stops or some...
Thanks very much.
the film is a ilford 50 panf
PD: sorry for my bad english :)

Responses

john cox , Jul 20, 2014; 12:12 a.m.

There's a few ways of doing this, one is to take a gray card (a piece of paper or cloth that is 18% grey) and meter the light in your scene falling on it. Another is to use an incident meter, which may be a function of your spot meter.
The concept of an incident meter is to measure the light coming towards the light meter instead of the light reflected off of (in this case the completely black ) background.
Making a grey card isn't too difficult in photoshop. The insides of a 35mm carton of kodak film usually works too.

ivan vilches , Jul 20, 2014; 12:19 a.m.

thanks john i have a gery card i can meter with spot of my camera and what more? should i take the diference on how many stops down compared with my candles?
thanks

john cox , Jul 20, 2014; 02:25 a.m.

In this case I would let the light from the candle fall onto the grey card and the measure the card. The idea is to measure something that's neutral toned and lit by the light your scene is using. There's no need to get into other complicated metering methods.

David Bebbington , Jul 20, 2014; 05:11 a.m.

There’s a simple and a slightly less simple answer to your question. The simple idea is that (assuming you are including the candles in the picture) the critical tone is the highlight detail in the flames, so spot-meter these and give 2 to 3 stops more exposure, according to which result you prefer. If you do so, the background will almost certainly photograph dead black.
The slightly more complicated method is to do the same as above but consciously think in terms of the Zone System:
http://en.wikipedia.org/wiki/Zone_system
This way, you spot-meter the flames as before. Any direct uncorrected meter reading applied to your camera setting will result in the tone in question being treated as zone 5 (mid-gray) – since this would result in over-exposure, you would need to place the spot reading from the flames on zone 7 (normal highlight) or zone 8 (brightest highlight showing detail) by giving 2 or 3 stops respectively more exposure. To make absolutely sure the background photographs dead black, you will need to treat this as zone 0 (which it almost certainly will be anyway). If you check and find the background is not zone 0 (i.e. seven stops less bright than the highlight if you have placed this in zone 7), you will need to move it further away from the light (candles).

There are a lot more responses to this novice photographers' question, but you get the idea.  Pay them a visit and tell me what you think.  'til next time - happy shutter bugging.

P.S.  You can check out my photography videos here:  https://www.youtube.com/user/DarrylMrT