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January 27th, 2010, 10:15 AM | #1 |
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Canon 7D Noise and Pixilation Issue - Please help
Hi Guys,
I was wondering if someone could help me... I have a canon 7d and i just can't get any good low light pictures without a load of noise/ pixilation. I was wondering if you could please take a look at my settings/ videos and see if there is anything you can recommend? Here are some videos where you can see noise on the left side of the subject's head. YouTube - New Noise Video - desat - Canon 7d. YouTube - New Noise Video - Canon 7d (these were exported from AF CS3 as mp4 - so things are a bit blurred, but you can see what i mean from the next vid) and you can really see it here: YouTube - Canon 7d - noisy footage issue (desatured) (look at the above right of the subject's head - where the white fades to black... it's like a pixil ant party up there!) Here are some stills that i extracted from other videos: http://i974.photobucket.com/albums/a...non7DNoise.jpg http://i974.photobucket.com/albums/a...oiseColour.jpg Here are my settings: Here is the set up I am using: Canon 7d Body Lens - Canon 50mm F1.8 Aperture: f1.8 Shutter Speed: 1/50 ISO: 200 24fps 1920x1080HD PAL White Balance: 5000k (matched to light source) Light Source 15w CFL Fluorescent lamp, (equivalent to about 60w - 75w incandescent) placed approx 1m away from subject's face. Camera Settings: User Def. 1 Sharpness = 0 Contrast = Absolute – Saturation = 2 clicks negative Color Tone = 0 (default) Highlight Tone Priority = Enabled ISO Expansion = Enabled Converting footage from Canon format to Avid ADxHD codec using MpegStreamClip and editing in After Effects CS3. All comments are very much appreciated Thx :) |
January 27th, 2010, 12:50 PM | #2 |
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I don't have experience with Avid formats, but I will say that I would need to see shots of the original to compare noise. The pixelation I see is from YouTube's h.264 compression for web and not related to what the camera shot. If you compress the footage enough with a low bit rate, you will see a lot of blockiness.
I also noticed that some of your uploads were a wrong aspect ratio. |
January 27th, 2010, 06:26 PM | #3 |
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New Video Example
Thanks Dave,
Here is an uncompressed video that i uploaded straight from the flash card. Any Thoughts? YouTube - Uncompressed Video - Noise/ Pixilation Issue |
January 27th, 2010, 07:09 PM | #4 |
Inner Circle
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Yep....
Noise = insufficient light Pixellation = weak h.264 codec in the 7D. Shoot the same scene at ISO 640 and see what you get.
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January 27th, 2010, 07:19 PM | #5 |
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January 27th, 2010, 07:24 PM | #6 |
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Why? Reduce latitude in the shot and nothing needs to blow out.
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January 27th, 2010, 07:32 PM | #7 |
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Because reducing latitude in the shot is not always possible or desired. For example, I don't normally carry a nuclear warhead bright enough to reduce the contrast in mountain landscapes. ;) Other times, I do have the nuke with me, but I just don't want to change the lighting because I like having highlights that are four (not three) stops above mid gray before clipping.
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January 27th, 2010, 07:39 PM | #8 | |
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Quote:
Ands sounds to me like you need to upgrade your arsenal to some include some smart, tactical nukes... Just to even things out a bit. Or you need a RED. :)
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January 27th, 2010, 07:46 PM | #9 | |
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Quote:
Or both. That's how they made Book of Eli. :) |
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January 28th, 2010, 08:26 AM | #10 |
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Thanks everyone - i'll play around and see how it goes.
dn |
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