Marty Molloy
May 26th, 2011, 01:38 PM
I have a problem that I'm not sure how to solve, using our two Canon XL-H1 cameras. We mostly do indoor greenscreen shooting and indoor "factory" shooting with whatever available flourescent lighting is available. The big problem we are seeing is that there is a lot of noise on the black parts of our shots, for example black pants or shirts, or on the black sides of computer cases, etc. There is a little noise showing up on other dark colors, but the black is where we see most of the "sparkling" going on. This seems to happen whether we are brightly lit up or not. For indoor shooting, the manual says selecting - 3db on the gain knob is preferred and I'm wondering if setting the gain at zero db would be better...I need to try this, and haven't yet. Also, some people here on the forum have mentioned using the Black Stretch function on the camera to help define the blacks in lower light levels, but I haven't yet found a good source that explains the proper ways to set your black levels. (if that's actually what I need to do) I've also read here on the forum that using a waveform/vectorscope could be helpful in determining the proper black levels on the camera, but I don't have the experience to know exactly how to make the adjustments to get what I need. I'd be very grateful for any insights from the pros here on what I can do to solve my problem.
Thanks in advance, Marty Molloy ;0)
Harry Bromley-Davenport
May 29th, 2011, 11:55 AM
"Neat Video" is an excellent plug in for noise removal and optional sharpening. I've used it on 2 features.
Harry.
Kevin Lewis
May 29th, 2011, 10:51 PM
Marty I have had the exact same problem and have made previous threads about it. I am shooting with the XHA1 but the issue is the same. I notice the problem more when using a green screen particuarly after I pull the key (even with studio lighting) after some experimenting, I belive that I may have found the problem. I think I was useing to low of a shutter speed. I was typically in the auto mode shooting 30frames. The camera was selecting a shutter speed of 30. When I bumped up the shutter speed to 60, the problem seems to disappear. I am still experimenting with this and cant say for sure that this is the problem, but it certainly seems to have helped.
Simon Wood
May 30th, 2011, 07:13 AM
Go into your settings and try this:
BLK: Set to Stretch
SHP: Dial down a few
COR: Dial it up
NR2: Set to Low
Mess around with those settings first. It will help to be watching this on an external monitor (or a HDTV) - the image will change as you alter the settings so will see in real time what works best for your lighting.
You should also play around with all the settings there, such as the KNEE and PED (and the rest!).
Exposure is important to get right.
Keep Gain at minus 3 where possible and increase lighting if necessary (0 gain will add noise). Shutter probably wont have too much of an impact, but it will effect other settings if you are in an automatic mode (I've never used them as I'm always in manual).
Marty Molloy
May 31st, 2011, 12:25 PM
Guys, thank you for the replies...I'll certainly have a good look at everything here. Much appreciated! ;0)
Carl Barlow
June 5th, 2011, 10:03 AM
+1 on the 'Neat Video' plug-in if you've already got footage you need to correct, which can't be re-shot.
This plug-in really saved my bacon on wedding video recently. Looked OK in the viewfinder in the dimly lit church, but when viewing the footage in post on a large screen the blacks were grainy. Neat Video really made the finished sequence look totally different. The only compromise was the rendering time, it takes ages and ages !
Marty Molloy
June 20th, 2011, 10:12 AM
Thank you, Carl! ;0)