EX-1 camera test with Camera Flashes

It's nasty, that's for sure, but it has not stopped that many from droppng $25K to $50K on the RED ONE which has the same CMOS issues.
 
philip bloom said:
I couldn't see anything wrong with it. Looks fine to me :-)
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Seriously Phil!?!?! It looks horrible... You've got a weird pair of eyes if you can not see that... no offence (actually I envy you, if you can't).


And for you guys asking if it will be as bad if you are not pointing the flash at the camera: Yes it will be just as bad.
However, depending on how strong the flash is and how far away it is from the surface it illuminates, the difference in exposure in the part of the frame that recives the flash and the part that does not will vary and make the problem more or less noticable.

For my part I need to know if it's only strobes that causes this partial exposure, or if it'll happen with other flashing lights. As most of the work I do is commercials and/or musicvideos. I guess I'll find out tomorrow, when I finally get one to test over the weekend.


Anyone want me to do some specific tests with the camera?
 
Used the EX1 at an auditorium with tons of flashes aimed at the stage. No partial exposure issues. So as you mentioned, it depends on flash strength.
 
I don't think that fixing in post is going to be that easy. Nobody yet has posted an example of a fixed strobe artifact and I've been watching for it everyday.
In a shot like Dan's here it wouldn't be too hard because the flash evenly exposes the whole picture ( or partial picture to be precise) so you could probably just throw a mask over the rest of the picture. But if the flash is further in the set so there are foreground elements unaffected, it will be rougher. I'd like to see some attempts at a fix.
 
Fixing a flash in a moving image, say a pan, would be quite a lot of work, and hard to do. Fixing a static shot would be okay, but if you are having problems with flashes you are probably in a shooting environment that does not leave time/money for these kind of fixes anyway...

It is definetively quite a problem if you are doing ENG og weddings or any kind of shoting out of an controlled environment where flashes/strobes would be present.
 
yeah. that actually works ok. still partial exposure, but you really have to look for it to notice.

However what I was thinking of was not "camouflaging" the partial exposure, like you've done here, but actually FIXING the frame, so that you combine the two frames that the flash is spread over and swap the flash-exposed and the not flash-exposed parts of those two frames...

There are a lot of times your method would work well, but I think that more often you would find that it would not do the trick (for instance where only part of the scene is affected by the flash, and the flash is not pointing towards the camera).
 
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Knoll ???

Knoll ???

mico said:
Heres another rough quickie from footage of the police car from FRESH DV sample " EX1 rolling shutter strobe artifact" here:
http://www.freshdv.com/2007/12/xdcam-ex1-cmos-rolling-shutter-strobe-artifacts.html

And heres the quick fix using Knoll. This short clip from the original has 3 fixes in it. You can see a small rolling shutter effect I did not fix at the end of the clip. The other fixes where distinct half frames.

http://rapidshare.com/files/91566927/police_flash_test.mov.html
Click to expand...

Fix looks good ~ so, what's knoll?
 
Knoll is really impressive. But this could still be a problem in the wilderness. Lightning tests, anyone?
 
Whoa, problemo el solved-o! That's amazing! Thank you Star Wars! As for lightning, next time I'm in the wilderness I'll hold my aluminum tent pole over my head like a lightning rod and record a direct strike. I may not be around to edit the footage, but if anyone wants to run it through Knoll Light Factory to see if it can be fixed adequately in post, please feel free.
 
I'll take you up on that, Buck! But let's take a moment to come up with a way that isn't quite so dangerous...

The EX1 is going to be my next purchase for narrative work, so the flash issue isn't an issue for me so much. But now I'm curious. What effect does recording in 60p for slow motion in a 24p timeline do? Do you still wind up with half frames? Forgive me if that's a stupid question.
 
I do not work for Knoll or red giant software but here is the link to info with video tutorials:

http://www.redgiantsoftware.com/knolllightfactory.html

Knoll does most of the work for you. Its got a bunch of preset light sources. As a plugin for Final cut pro, which I use, you just pick a light source, tweak the design of your light source, move it to where you want on your image and you can adjust intensity and size as well as shape , flare whatever. Really a no brainer to use. Now these were non moving light source fixes so it was very fast and easy to do. Knoll gives you the ability to keyframe the source to moving images which would be more difficult work and which I haven't tried yet.
 
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