Exposure Tests

Okay, time for Hedda to earn her keep. We set Hedda up on her stand in the living room. Clamping a poly green screen to the entertainment center with spring clamps and placing the camera on a tripod.
After some initial trial and error, we came up with Hedda being about 4 feet in front of the backdrop and the camera being about 4 feet in front of Hedda. This should tell you that you'll need at least 10' of working area in the room you choose. See Below:

In the following shots we're using our Kodak DX7630 camera. After much experimentation, we've got to hand it to Kodak. We've tried every combination of aperture/shutter speed and the Auto or Program mode did every bit as good.

All the shots below are taken in Program mode with an aperture setting of f4.0 and a shutter speed of 1/90, ISO 100.

My old green poly background is getting pretty wrinkled. Seeing it in these shots may make you decide not to go the poly route. It's really hard to keep wrinkles out of them and they tend to get hot spots much worse than say, green paper.



Here are our results:

Shot 1
In this shot we have no background flash compensation at all. Notice the hard shadow on the left side. This comes from the flash being offset to the right side of the lense on the camera (when viewed from above) This shift from the plane of the lense causes more grief than anything else. If it weren't for this, the standard flash on the camera would probably be sufficient.

Shot 2
In this shot we have hard background flash. Note the harsh hi-lights on the hair. We'll put a shirt on Hedda in the shots below to help compensate for this but in general, we're closer than in Shot 1 to having a consistent background.

Shot 3
In this shot we have very  harsh background flash, held higher and to the left of Hedda. This is pretty extreme, although, we're going for an easily separated background, not a pretty one. This shot might actually work well.

Shot 4
In this shot we have good even background flash that kills the left hand shadow. The mini-slave flash was a bit higher than in the diagram at the top of the page and offset a few feet from Hedda. It was draped with a single (2 layer) facial tissue to take the hard edge off the flash. This shot is a little uneven in background brightness from left to right, but the shadow is all but gone and the rest is easily separated.

Shot 5 - new series
Here's Hedda with her shirt on. This more closely replicates an actual portrait subject (I hope you're not shooting heads on sticks anyway!). We simply straighten the hook on a metal hanger and drove it up into Hedda at around the rear hair line (ouch!). These cosmetology heads are a dense foam inside so they will accept a metal hanger very well.
In this shot, Hedda has only natural light for lighting. There was a window approximately 3 feet behind the camera and to Hedda's left. It was a moderately sunny day so we did get some nice natural lighting. Note the lack of shadow on Hedda's right side because of the lack of flash. The background is a bit dark but could be workable. I think we can do better though.

Shot 6
In this shot we have very harsh background flash spill onto the hair. Number one rule of background lighting, IT SHOULDN'T SHOW ON THE SUBJECT. Shot is un-usable. Look for this spill in your test shots and adjust your flash away from your subject to kill it

Shot 7
Now we're talking. Remember, we're going for an easily separated background, not a pretty composition. Hedda is adequately lit from the front by the camera flash and the background, while appearing a bit fluorescent, would be very easy to separate. This shot was done with the same setup as in the diagram at the top of this page. The flash is below (3') and behind Hedda (2'), offset to her right about a foot and angled up at around 45 degrees. Sit the flash on a kitchen chair or small end table if you don't have a stand for it. This shot is VERY workable. There's a high level of contrast between the background and the hair. It may look a little extra harsh on your camera LCD screen so be sure to check them on a computer before you discard shots like these.

Shot 8
The final shot in this series of tests. Same setup as above but this time, a facial tissue (2 plys) is laid over the flash. Note the softening of the flash. This may be just what you need to even the background out. An additional flash might have been used from the right hand side to help even out the background but it's very usable.

Well, I hope seeing these examples has helped. Experimenting in this way is a great way to find out what you'll need when you're using actual people (without blinding them). In coming tutorials we'll use Shot 7 and Shot 8 to start experimenting with different cutting techniques to knock Hedda out........!