Getting high contrast images?

egearbox

egearbox

Member
I've had my DVX-100A for a long time, but haven't experimented with it much. Now I'm trying to "get serious" about making a film with it, and I'm having trouble getting the images I want out of the camera. No matter what settings I try, the exposures seem to all be low contrast and washed out, not using the full range from black to white.

If I open the iris I get washed-out bleached looking images, and if I close the iris I get dark, muddy images. I can't seem to find a way to get an image that runs from black (0,0,0) to white (255,255,255) in the same frame - or anything even close!

If I put the clips in Aftereffects I can see that the histogram of exposure ranges is very narrow.

My question - what can I adjust on the camera to increase the exposure latitude (if that's the right term)? I've been through the manual and it's full of less than helpful things like "Gamma: This setting controls the gamma." It doesn't tell you what the gamma affects, or how it interacts with other settings.

Anybody out there know the magic formula?

Thanx in advance - Tom
 
Do you have Barry's book and DVD? Those will help answer your questions.

I'm wondering, however, whether there's something wrong with your camera. It shouldn't be that hard to find things to shoot that will not be washed out. Could you post frame grabs of your best efforts?
 
Yeah, we'd have to see some examples. To increase contrast, use the black press gamma, lower your master pedestal some, and set the knee to high.

You can use the "marker" to spot-check what the IRE settings are on your image; it'll tell you the brightness on a scale of 0 to 100.

Also, make sure you have "setup" set to 0%! If you have it set to 7.5% it's actually going to prevent you from getting deep rich blacks.
 
I don't know if you thought about this yet, but that is a good reason to have lights. Cut out all the light sources in a room, and turn one bright one on your subject and that should give you some great contrast.
 
Here are some frame grabs out of AfterEffects showing the levels histogram for these raw frames. The scene was lit from frame right with 2 500W halogen lamps with 1/4 daylight gels on them, and the background is two sheets of black foamcore. I was hoping this setup would give me solid blacks and bright whites. Instead as you can see, if I iris down, I get blacks and midtones but no whites, and if I open up the iris I get bright whites but nothing at the low end.

Scene file settings are:
Detail level 0
Chroma level +3
Chroma phase 0
Color temp 0
Master ped -5
A. Iris level 0
Gamma Cine-Like
Skin tone dtl OFF
Matrix Cine-like
V Detail Freq Thin
Progressive 30P

Is this settings, lighting or operator error? :)
 

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John_Hudson said:
My god

Shoot flat; alter in post.
Click to expand...

Hmm... So, just take whatever the camera gives you and fix it in post? I've heard that's not the best idea. I was really hoping for something better for $3,500.

If by chance that's NOT what you meant, could you expand on your suggestion a little?
 
My suggestion is get the truest image you can. Once you've lost the image, it's gone; forever.

High cnotrast ? Blown out whites ? No chance in hell of ever getting the recorded information back. Crushed blacks ? Shadows showing nothing ? Gone.

Getting a true image ? I'll take my footy into post and always have what was in the frame. I can adjust levels, contrast and curves to my delight.

-

You have to do what works for you. Maybe with the monitor and waveforms one can get the perfect image in-camera, but better to have the options later I think.
 
well if thoes two images are your extremes, why not close the iris half way, and get proper exposure inbetween.
 
The answer to high contrast

The answer to high contrast

Since I finally solved the problem I was having, I thought I would post it back so that maybe - noob to noob - I can HELP somebody.

The answer to my low-contrast image problem turned out to be getting the hell away from the Cine-Like gamma setting. I bought Barry's book and on page 62, he points out that Cine-Like gamma "actually gives the shot more latitude".

That might be great if you have $10,000 worth of lights sitting around, but if you're trying to shoot with very limited lighting AND record images with the most dynamic range IN THE IMAGE (as opposed to what the camera might be capable of), then stay away from Cine-Like gamma. I turned the Master Pedestal down to -4 and went with High gamma, and I was able to get much more range out of the images - example attached.

By the way, if anybody has any suggestions for improving these results further, I'd be happy to hear them...
 

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Yeah... drop your master ped to -12 and see what happens.

I agree though... I shoot about where you're at now, and up the contrast in post just to not have any blowouts or blacks.

fix22.jpg
 
I tried your suggestion, but I think I'll stick with the MP at -4 for now. Anything more (minus 8 for example) seems to slam the blacks right down to zero. I'd rather have a little wiggle room, for the very reason you stated.

That being said, I'm much happier with the images I'm getting now! Thanks to Barry for writing his book.
 
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