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02-28-2010, 10:15 AM   #1
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Achieving low-noise footage?

I've made a few videos with my K-7 and K-x now, and something I've noticed in all of them is that the video is a bit noisy (my worst case so far is this: )

While browsing on Vimeo, I saw these videos, taken with a 7D:



The video quality is amazing! If you look at the blacks, there's barely any noise, and everything looks incredibly sharp. I'm thinking it is probably post-processing with lots of good light, though that 2nd video looks good in candlelight. Apart from the bleached look, how do I make my video look as clean? Is there some filter(s) in FCP I can use to reduce noise?

- Jason


Last edited by inferno10; 02-28-2010 at 10:24 AM.
02-28-2010, 11:08 AM   #2
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Panasonic GH1 also looks good in 1080p @ 24fps

[vimeo]http://vimeo.com/moogaloop.swf?clip_id=7517485&amp[/vimeo]
02-28-2010, 01:06 PM   #3
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inferno, it's easy to get good quality out of footage like that, especially the second clip, because there is little motion in it, and there is a bunch of out-of-focus areas in the frame... by comparison, your pillow fight footage is an total encoding nightmare.

if you pause the pillow fight clip, you can see that it's loaded with compression artifacting... if that artifacting is not there in the original footage, it was caused by your editing workflow.
02-28-2010, 05:54 PM   #4
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With video as I understand it the importance it LIGHTING! Lots of it!

A good fast lens like a FA50 1.4 prime for example would help.

Then trying to ensure the camera is on a lower ISO (which cant be directly done manual at this time) I find that by shining or aiming the camera at a bright light source and using AE-L as well as also turning down the EV can help to.

In post processing remember when you encode and downsize your footage for internet it hide a lot of the noise, other things is noise reduction in post processing another thing to get clean blacks is using Photoshop extended and applying a curves adjustment, done carefully it can make the blacks look black.

02-28-2010, 09:52 PM   #5
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Use 50mm manual lens f1.4

Or 28mm manual 2.8 if you want a wider image.

set WB to AWB
Chose vibrant

or choose WB
Tungsten or Shade

Next

set the dial to P
select iso 400 or 800
open aperture all the way
point the camera towards a light source till the shutter indicates 1/25
lock auto exposure this requires that you have set the AF AE-L button to lock see manual for this.
When you managed to stet 1/25 shutter either ISO 100 200 400 800 or 1600
turn the dial to camera mode. Don't push the AF-L button again.


ISO 1600 will give you the most noise but be the brightest
ISO 800 will be Ok for really dim light
ISO 400 will be good for City streets at night.
ISO 200 you'll need some more light.

Only use the aperture ring to control the brightness

Set the shutter 1/25 is a little tricky


this way I found out having the most control over the outcome.

You also can leave everything on just automatic. The brightness, however is then difficult to predict.
02-28-2010, 11:19 PM   #6
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Ive tried your method but exposure isn't locked in camera mode and even with AE-L in P mode changing ISO changes the shutter speed.
03-01-2010, 12:16 AM   #7
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You have to use a manual lens

The iso has to be set before you lock the auto exposure.

then turn the dial.

Each of the iso settings will have a different brightness.

03-01-2010, 02:05 AM   #8
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Do NOT use auto white balance like advised before!
A proper white balance is important to keep noise as low as possible, auto white balance most of the time does not provide a good result.

You may want to read these very useful and important tips on how to optimize your recording/post processing of video with DSLRs:

http://prolost.com/blog/2010/1/26/color-correcting-canon-7d-footage.html
03-01-2010, 06:53 AM   #9
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I was suprised the difference switching between the preset colour modes on the K7 and how it effects the image noise, Pentax really needed to better document this, I think they totally underestimated the potential of video on a DSLR.
03-01-2010, 12:28 PM   #10
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here is a video I made tying out some WB settings at iso 400

[yt]http://www.youtube.com/watch?v=LWrQU30WR-E[/yt]
03-01-2010, 01:59 PM   #11
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Interesting result. I will need to try a static position and see what out put I get.

I think much of the garbage I'm getting occurs when I export my source footage into ProRes (Proxy) format. Maybe I'll try working with my original footage in FCP and see what spits out.

- Jason
03-02-2010, 12:08 PM   #12
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you mean import into fcp, not export? prores is an xlnt codec, it's probably a visually lossless transcode from the pentax mjpeg... prores shouldn't be an issue.

you are probably getting the compression artifacts when you export the timeline, for the vimeo upload... one or all of the bitrate/framesize/codec choices are wrong.
03-02-2010, 10:57 PM   #13
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QuoteOriginally posted by osv Quote
you mean import into fcp, not export? prores is an xlnt codec, it's probably a visually lossless transcode from the pentax mjpeg... prores shouldn't be an issue.

you are probably getting the compression artifacts when you export the timeline, for the vimeo upload... one or all of the bitrate/framesize/codec choices are wrong.
I actually export my source videos to ProRes 422 (Proxy) then bring into FCP.

What bitrate and codec do you recommend? I usually export the edited video using h.264, auto bitrate, HD 1280x720 16:9 resolution, and AAC audio.

- Jason
03-03-2010, 11:10 AM   #14
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it looks to me like your workflow is pretty solid.

although proxy editing usually infers that the editor is bringing the original source footage back into the timeline for the final export, in other words, the edit was done with low-bitrate copies of the source, that have the exact same timecode, and the source was substituted for the proxy for the final export off of the timeline.

it appears to me that you are transcoding pentax mjpeg into prores 422, and never touching the source footage again, which means that you are editing with an intermediate codec... that usually works pretty well, because you have a lot of bitrate and color space available for doing things like noise removal.

so you did it like this?
1) shot at 1280x720.
2) transcoded to prores at 1280x720.
3) exported final edit at 1280x720, to either prores or your h.264 encoding software... if you export a prores clip, it might allow you to find a better h.264 encoder, although you gave the vimeo upload a ton of bandwidth, which was very smart... lots of bitrate helps to overcome a bad encoder, and the apple h.264 encoder is not one of the best you can use.

i edit on a pc, sorenson squeeze would be the only encoder i've used that we have in common, it think it uses the mainconcept mpeg-4 software... nero is my first choice for mpeg-4 uploads that have to be re-encoded by youtube and such.

i downloaded your vimeo source, it is indeed very noisy, as you indicated earlier, but there was little or no compression artifacting, so i'm wondering if the vimeo encoder gagged on the noise, and gave us all of that artifacting... it would be interesting to see if youtube does a better job of encoding that same vimeo source clip.

you could try experimenting with some noise removal software on the editing timeline, using prores transcoded files, and see if that improves the vimeo encoding.
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