p.2 #1 · How to shoot still life's with a black background?
DO you mean banding and other rasterization? That would be due to the the blacks not being black enough (not enough light, so it becomes a bit noisy) in addition to high compression when saving your file.
p.2 #2 · How to shoot still life's with a black background?
I believe so Skarkowtsky. So are you saying that I don't have enough light on the black background? What is the standard, 2 to 3 stops darker than subject exposure?
p.2 #3 · How to shoot still life's with a black background?
Skarkowtsky wrote:
DO you mean banding and other rasterization? That would be due to the the blacks not being black enough (not enough light, so it becomes a bit noisy) in addition to high compression when saving your file. AIBlackberry wrote:
I believe so Skarkowtsky. So are you saying that I don't have enough light on the black background? What is the standard, 2 to 3 stops darker than subject exposure?
Some pretty weird terminology going on here. Rasterization is the transforming of a vector to a bitmap, and while the process may ultimately cause blocking or banding, it is a process not an effect.
If a background, or anything else for that matter, is not black, then it cannot be due to too much light. If blocking occurs it is because there is some recorded level above RGB(0,0,0) which hasn’t been clipped to black.
If you want a jet black background, then it needs to be at least three stops below metered exposure. Alternately, you can clip the shadows to black in post processing; an easy task in Lightroom or Photoshop.
p.2 #4 · How to shoot still life's with a black background?
Hugowolf, can I meter on the subjects' face at 8.0 and have a black blackground 10 ft from subject with no light on it at all and this cause the "blocking problem"? Or do a I need to meter the same way you would for a white backgound? Thanks for the information
p.2 #5 · How to shoot still life's with a black background?
, I realize how my post reads. Oops. What I meant was if there is a just enough light illuminating the black background to the point where it's almost a uniform black, but has some lighter patches, it might appear noisy, and also might include banding in the lighter spots when saving the files out in compressed formats.
p.2 #6 · How to shoot still life's with a black background?
AIBlackberry wrote:
Hugowolf, can I meter on the subjects' face at 8.0 and have a black blackground 10 ft from subject with no light on it at all and this cause the "blocking problem"? Or do a I need to meter the same way you would for a white backgound? Thanks for the information
If you have blocking in the background, then the background isn’t jet black. There is the possibility that your raw conversion software is trying to drag something out of nothing, but more probably, it isn’t actually black.
What does your histogram look like? Do you have clipping on the right that would indicate that at least something in the image is totally black?
It isn’t the distance of the background that is important, it is the ratio of the distance from the light source to the subject compared to the distance from the light source to the background. If your lights are 10 linear units from the subject and the background is 10 units from the subject, then a quarter of the light is falling on the background and you only have two stops difference between the subject and the background.
Yes, meter the background. If your subject is at f/8, then what reading do you get at your background. Also look at your histogram after taking the shot and make sure you have black clipping.
I don’t know what PP software you are using, but in Lightroom you can simply clip the shadows to black by pulling the Blacks slider to the left in the Basic section of the Development module. The Sshadows slider in the Tone Curve section isn’t as effective, because it tries to preserve shadow detail. In Photoshop, the Levels tool is the easiest way to clip blacks, just pull the leftmost Input slider a little to the right.
In either of these programs you can move your mouse/pen pointer over the areas you expect to be black, and see if they indeed lack any values. In Photoshop, open the Info palette, then move your pen/mouse cursor over the image.
In the LR Development module, there should be an arrow head at the top left of the histogram (ctrl+0, as in zero, not Oh, to display the histogram if it isn’t already displayed), if you hover over the left arrow head, areas clipped to black should be displayed in a bright blue overlay on the image. Also, with the histogram visible, hovering the mouse over the image will display RGB tonal values as percentages (0,0,0 = black).
p.2 #7 · How to shoot still life's with a black background?
AIBlackberry wrote:
...can I meter on the subjects' face at 8.0 and have a black blackground 10 ft from subject with no light on it at all and this cause the "blocking problem"?
Can you explain in more detal -- or better yet, post an example --of what you mean by "blocking problem"?
A black background...a truely black one... doesn't need to be metered; you make it as dark as you possibly can by using a black backdrop material, and control the lighting on the subject to prevent any from spilling onto the BG. (If you have enough fall-off and well-controlled ambient you can make a white BG or a gray BG or any other kind of BG look black, but it's easier to start with black to begin with.)
AIBlackberry wrote:
...Or do a I need to meter the same way you would for a white backgound?
p.2 #8 · How to shoot still life's with a black background?
jzucker wrote:
Here are a couple more. These two were done with a pair of accent lights and a beautydish for fill light ala cgardner's suggestion.
Just to clarify, chuck didn't suggest the dish. I just choose that as my fill to concentrate the fill light without it hitting the bg
I use a dish as fill for portraits because it has wide footprint generating lots of wrapping "spill fill" but only a very small, easily removed catchlight. I would not and have not recommended it for when the goal is to keep light off the background.
The variable not seen in the photos or the diagram is the spill fill. Put a wide angle lens on the camera, go as far back as you can, then take a set-up shot to help visualize where light might be bouncing off the ceiling and walls onto the black background. It might not be a significant factor, but it will lift the overall flash created ambient fill level.
If you find it is a problem try black draping around the subject to kill the spill. I've found king size black top sheets from Walmart to be a a covenient and relatively inexpensive source for black draping.
, I realize how my post reads. Oops. What I meant was if there is a just enough light illuminating the black background to the point where it's almost a uniform black, but has some lighter patches, it might appear noisy, and also might include banding in the lighter spots when saving the files out in compressed formats.