Terrible Light bleed with Metabones & EF lens's, see attached.

R

re_curly81

Active member
We did an in-studio interviews shoot with a overexposed white background today. 2 camera setup #1 5D with 70-200mm L Series, (see attached zoomed, looks great), and FS100/Metabones/EF 17-40mm F4. (see attached wide, all washed out, there was no direct studio lights hitting the lens)

I think because of the full frame lens, the white light spilled/reflected onto the Sony Sensor, causing the washout image. Lesson learned.

I'm very disappointed to see this. Yes, it is a lot of white light, yes, I'm mixing full frame with super35, and using adapters, etc, but there are a lot of people using FS100 / adapters / Canon EF combo's, so just a warning to those out there.



FS100.jpgCanon 5D.jpg
 
Looks like veiling glare from the overly bright white background. It is possible that the effect is exacerbated somewhat by using full frame lenses compared to ones with a smaller image circle, but image circles are rarely exactly the size of the format intended and in any case, a matte box or flags would easily fix any glare occurring from light entering lens from outside the frame. More likely its also just the characteristics of that lens that cause it to show some veiling glare when contrast is so high and the background is so far above clip. That could be reduced by avoiding overlighting the background. For the sensor, white clip is white clip and it doesn't care what's there beyond clip, but for the lens, any extra unnecessary brightness in the scene beyond clip is just going to affect your contrast.

Was that background a backlit diffused background or a white wall/bounce? In either case, light is light so even if the initial studio source was not hitting the lens, a strong light source was hitting the lens. Looks like backlit diffused background from the spottiness of it. If that is the case, its also possible some undiffused rays were hitting the wide lens and not the zoom, right? Could you see the position of the (hard?) source through the diffusion with your eye from the camera's position?
 
Did you get to compare the same set up on the 5D and FS? If the 5D was on a longer length then there's a lot less light hitting the lens. As Noah mentioned it looks just glare from the background more than anything else. It would have been good to side by side the two cameras with the same lens to see whether it's the lens or camera.

I don't really see how the metabones could be blamed for this though, a dumb adapter would let the same amount of light through (in fact less, because the metabones has a mask to cut down back reflections like the sony emount lenses themselves)

cheers
paul
 
Have you tried the other way around... wide on Canon, close-up on FS100? To be honest, I think this is more choice of lens and lighting than it is an adapter problem. You really spotted that background which is visible with an anti-glare monitor and then looking at it from a steep angle.

At white background lit too far is like one big source of light and when you place your talent too close, light is going to wrap around and continue towards the camera giving you that glare.

Besides... why are you using the "bad" camera on the close-up and not on the wide?
 
I seriously doubt Full Frame lenses would cause any problems since APS-C crop lenses are relatively new. Many people use older Nikon and Canon FD still lenses from the 70's to 80's on their FS cameras, and those are technically all Full Frame, since thats was the main option before digital came about.
 
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I really dont think the cause was the wide angle lens, as it was zoomed to 40mm. The background was not much past 100% peaking, likely less as there is still visible detail. The subject was about 6' away from the white paper background with a lowel tota behind him. I have a second shoot with this setup coming again, and i can try swapping lens, but i doubt it will improve things. I will throw on a EFS aps-c lens too, which will quickly reveal if that is really the issue.
 
Hi .
Maybe this is the problem, I have a canon 5D mark 2 and a Sony F3, the colors in the F3 is turned all down to be able to give them a boost in post, while on the canon 5D is turned all the way up, in fact there is a video on youtube where Phillip Bloome explains how to turn the colors/contrast down on the Canon 5D to be more video friendly.
 
Sorry am I the only idiot who don't see whats wrong with the wide shot (other than the darker corners of the frame that aren't overexposed.)

I can tell they are different - the tight has richer colours. But without seeing the subject with my own eyes I can't tell which is a more accurate representation of the real thing.
 
Another cause can be a poor quality UV filter, I too agree this is a case of a lot of light bouncing around inside the lens causing flare. This will drastically reduce contrast, and looks just like that.

Some lenses are worse than others especially one w/o anti reflective coatings on the back element. You can get light bouncing off the imager and back again from the back element. If this is the case you can find out by having a bright square in an otherwise dark scene and see if there is a ghost image as you move the lens around, this can also be caused by a poor UV filter as I described above.
 
It's the 17-40mm lens that has the problem, not your lighting, and not your lens adapter.

I am guessing that you were shooting wide open with the 17-40mm ?

Stopping down the lens and masking it for flare ( with a matte-box and flags, and gobos in front of the camera ) should fix your problem.
 
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