How much ambient lighting in a home studio?

jwbryson1 · Mar 11, 2012

I moved my tiny studio to my unfinished basement so I would have more room to work and to kill some of the ambient light that plagues me on the upper floors. Now that I'm in the basement, I am trying to figure out how much ambient lighting is "okay" to get the shots I want. I am trying to shoot simple portraits with a blacked out background. I have a black muslin backdrop and a 10'x12' black muslin backdrop laid out on the floor. I have eliminated most of the ambient light (I'm working with a single bulb just to see what I am doing). Seems kind of silly to be working in the "dark" but it is the only way I can get the muslin on the floor to be completely clipped.

Issues I am having:

1. My photos are coming out very grainy. I'm shooting with a Nikon D90, ISO 250 to 400, f/8 to f/13, and 1/250. Anybody know why the images are so grainy under these conditions?

2. Any suggestions for having the muslin under the subjects be clipped like the background?

Thanks!

Derrel · Mar 11, 2012

No need to work in such low light. The answer to "how much ambient light?" can be ascertained by taking a few photos...at ISO 250 to 400 and an aperture within the f/8 to f/13 range, the shutter speed of 1/250 will not record much of an image unless the ambient light is very strong. So---take some photos with the flash units turned OFF, and then evaluate the resulting images, which should be very,very DARK images, or even almost black. I think you could easily work with two or three 60- to 75 Watt bulbs on in the room with no issues.

As to the grainy pics....hmmm...I cannot imagine why the images are not clear and sharp as long as the flash and shutter are truly in-synch. I would re-check ALL camera settings and verify that the flash units are all properly synched to the shutter.

Question #2--I am not sure what you are asking.

jwbryson1 · Mar 11, 2012

Derrel said:
No need to work in such low light. The answer to "how much ambient light?" can be ascertained by taking a few photos...at ISO 250 to 400 and an aperture within the f/8 to f/13 range, the shutter speed of 1/250 will not record much of an image unless the ambient light is very strong. So---take some photos with the flash units turned OFF, and then evaluate the resulting images, which should be very,very DARK images, or even almost black. I think you could easily work with two or three 60- to 75 Watt bulbs on in the room with no issues.

As to the grainy pics....hmmm...I cannot imagine why the images are not clear and sharp as long as the flash and shutter are truly in-synch. I would re-check ALL camera settings and verify that the flash units are all properly synched to the shutter.

Question #2--I am not sure what you are asking.

Thanks Derrell. I suspected the answer to Q1 was going to sound something like that. As long as I have the correct s/s I should be able to kill the ambient light. I have a low window out the back of the house that lets in a TON of light--almost like a HUGE snoot shooting directly at where my subject is sitting. :lol:

I covered that window because it seemed to be having an effect even at 1/200.

On my second question, the muslin in the background is completely clipped as intended. I have a second 10'x12' muslin cloth on the ground for my "models" to sit on so that the blue cement floor does not appear in the image. I am using 2 reflective umbrellas and they are lighting up the model and the black muslin "flooring" enough that the texture of the muslin shows (along with white pieces of dust, etc.) that gets all over everything black. I'm wondering how I can get the muslin under them clipped too so it's completely black.

Does that make sense?

gsgary · Mar 11, 2012

jwbryson1 said:
Derrel said:

No need to work in such low light. The answer to "how much ambient light?" can be ascertained by taking a few photos...at ISO 250 to 400 and an aperture within the f/8 to f/13 range, the shutter speed of 1/250 will not record much of an image unless the ambient light is very strong. So---take some photos with the flash units turned OFF, and then evaluate the resulting images, which should be very,very DARK images, or even almost black. I think you could easily work with two or three 60- to 75 Watt bulbs on in the room with no issues.

As to the grainy pics....hmmm...I cannot imagine why the images are not clear and sharp as long as the flash and shutter are truly in-synch. I would re-check ALL camera settings and verify that the flash units are all properly synched to the shutter.

Question #2--I am not sure what you are asking.

Click to expand...

Thanks Derrell. I suspected the answer to Q1 was going to sound something like that. As long as I have the correct s/s I should be able to kill the ambient light. I have a low window out the back of the house that lets in a TON of light--almost like a HUGE snoot shooting directly at where my subject is sitting. I covered that window because it seemed to be having an effect even at 1/200.

On my second question, the muslin in the background is completely clipped as intended. I have a second 10'x12' muslin cloth on the ground for my "models" to sit on so that the blue cement floor does not appear in the image. I am using 2 reflective umbrellas and they are lighting up the model and the black muslin "flooring" enough that the texture of the muslin shows (along with white pieces of dust, etc.) that gets all over everything black. I'm wondering how I can get the muslin under them clipped too so it's completely black.

Does that make sense?

You are going to stuggle using umbrellas because the light is not very controllable so you are getting lots of light falling where you don't want it, softbox with grids would be better or beauty dish with grid
This shot was shot with a snoot and grid, camera is on cheap black material

Derrel · Mar 11, 2012

The big window *might very well* be causing a slight bit of of a secondary or so-called "ghost" image. SO, covering that makes sense, especially if there's outdoor sunlight coming in. Direct sun, or even bright skylight COULD very easily be bright enough to make an exposure at ISO 400 and f/8 at 1/250...that's actually about the right exposure in the springtime a lot of places, so....yeah, covering up that window makes sense.

Well, if the PEOPLE are sitting on a black muslin, and they are lighted up pretty well, I think you'll find that lint and such will show up. Especially if a good part of the umbrella's light is hitting the muslin. If you are trying to get the floor-covering muslin JET BLACK, you're going to need to use a smaller camera exposure to "drive it downward" in the exposure curve. A second option would be to have the people seated on stools, and just a bit farther away from the muslin, so that light fall-off itself will cause the light at the floor to pull the muslin down to JET black.

A third option might be to adjust the images in post, and pull the bottom left (the shadow portion) of the curve "down and to the right" a wee bit, thus making the shadowed parts of the images really,really black.

The problem is that the lights lighting the subject and the floor-covering muslin are lighting basically the SAME AREA, and at an intensity level that is close enough so that the black muslin shows detail and lint. SO, there are basically three remedies I can think of off the top of my head: move the subjects UP, and onto posing stools or chairs or a bench or settee or big wooden blocks (a good thought! blocks!). You could also move the lights EVEN CLOSER to the people, so that the fall-off will be really,really rapid. You could also under-expose the people a bit. Or, tweak the curves to drive that black wayyyyy down to jet-black.

Umbrellas are very broad light sources...they can be a PITA in close quarters, small-studio use.