Experimentation.Don't wait for the Nikon D-whatever, have fun now!http://www.flickr.com/photos/j_wijnands/..

I believe it's generally the dynamic range of your camera. So if you have a Canon A710 IS, which has about 6-7 stops of dynamic range, then anything behind the object youve metered will need to have 7 stops less light reflecting from it to appear black. Better cameras with greater dynamic range will require more stops difference...

Do a google search on "Ansel Adams" and "Zone System" that should explain the stop variation you need (generally about four)..

Here's the wikipedia link.http://en.wikipedia.org/wiki/Zone_system.

'Nice pen, bet you write good stories with it.'..

BabyRebel wrote:.

Hi,.

Instead of putting a black backdrop, I have heard that if thebackground of subject is "X" stop darker than the subject, the endresult will be that the background will appear black. How do you findout how many stops the background is darker than subject?.

If you are talking of reflective metering, light measured by a camera from the subject and background, then much would depend on the tonal value of the subject. If the subject is dark, then not much difference. If the subject/object is nearly white, then as many stops as the sensor has in it's dynamic range..

For an average subject, 3 or 4 stops is usually plenty..

Without a black background, you need to put some distance between your subject an the background, unless you can prevent the lights aimed at the subject from falling on the background..

Brian A...

BabyRebel wrote:.

Hi,.

Instead of putting a black backdrop, I have heard that if thebackground of subject is "X" stop darker than the subject, the endresult will be that the background will appear black. How do you findout how many stops the background is darker than subject?.

Thanks.

Just use PP...

Apiron wrote:.

Just use PP..

That is not an answer for everything. I have spent several hours overnight colour desaturating the background to 25 photos of a stage performance in rehearsal. It was a pain..

If a bit of though before taking such photos could have eliminated that need then it would have been worthwhile..

Chris Elliott.

*Nikon* D Eighty + Fifty - Other equipment in Profile.

Http://PlacidoD.Zenfolio.com/..

BabyRebel wrote:.

Instead of putting a black backdrop, I have heard that if thebackground of subject is "X" stop darker than the subject, the endresult will be that the background will appear black..

First of all, it depends on the subject. If it is conveniently mid-grey, then four stops as others have suggested, or five to be on the safe side, will be basically black (or at least very dark). But not all subjects are mid-grey, are they?.

The other point I would want to take into account is whether the background is to be a featureless flat black, or just very dark but still with some depth and texture. Both are valid, depending on the situation..

How do you findout how many stops the background is darker than subject?.

By spot metering...

As long as the background is even slightly darker than the rest of the image, selecting it automatically and making it completely dark is easy. No need to worry about how many stops of difference you need, anything is enough, that was my point..

Chris Elliott wrote:.

Apiron wrote:.

Just use PP..

That is not an answer for everything. I have spent several hoursovernight colour desaturating the background to 25 photos of a stageperformance in rehearsal. It was a pain..

If a bit of though before taking such photos could have eliminatedthat need then it would have been worthwhile..

Chris Elliott.

*Nikon* D Eighty + Fifty - Other equipment in Profile.

Http://PlacidoD.Zenfolio.com/..