View Full Version : What settings do you use for low light situations?
Bill Edmunds November 6th, 2007, 06:57 PM I videotape a lot of events where supplemental lighting isn't allowed. That being the case, I've been experimenting with the best settings for the HVX200 at 12db of gain. I"m looking to get the best possible image with th e least amount of noise, obviously. I know the HVX200 is an inherently 'noisy' camera, but what Can I do to minimize the noise? I've lowered the pedestal for a start (-3 or so), boosted the coring (+7), and tried different gamma settings (cine V usually). I'd love to hear what others have tried. My problem is that in reducing the noise I"ve also managed to reduce the overall brightness of te image. A trade-off is inevitable, I know.
Robert Lane November 6th, 2007, 09:08 PM First, don't use either the Cine-V or D settings; they actually raise visible noise. Just use the HD NORM setting instead.
B-PRESS gamma will help reduce noise more but will also crush blacks - not exactly what you're hoping for.
If you don't have to have HD res, if you can shoot DV50 instead the image will be 50% cleaner right off the bat. The higher-than-average noise levels most complain about with the HVX is when it's in HD mode; the spatial-offset mode on the chip is what causes the extra noise. When the imager is in it's native SD res the output is amazingly clean - better than DVX100B especially at DV50.
Unfortunately you're smack-in-the-middle of the HVX's achilles-heel, which is low light and high gain. Your best bet is to use "normal" settings and reduce noise in post if you shoot in HD.
Bill Edmunds November 6th, 2007, 09:47 PM First, don't use either the Cine-V or D settings; they actually raise visible noise. Just use the HD NORM setting instead.
B-PRESS gamma will help reduce noise more but will also crush blacks - not exactly what you're hoping for.
If you don't have to have HD res, if you can shoot DV50 instead the image will be 50% cleaner right off the bat. The higher-than-average noise levels most complain about with the HVX is when it's in HD mode; the spatial-offset mode on the chip is what causes the extra noise. When the imager is in it's native SD res the output is amazingly clean - better than DVX100B especially at DV50.
Unfortunately you're smack-in-the-middle of the HVX's achilles-heel, which is low light and high gain. Your best bet is to use "normal" settings and reduce noise in post if you shoot in HD.
What do you recommend for reducing noise in post?
Robert Lane November 7th, 2007, 08:55 AM I don't really have any single recommendation; there are several built-in filters in FCP to do the job (in combination) and of course plug-ins like Magic Bullet which also have their own methods. When I've shot low-light situations I always planned for it by either shooting film or using a larger-chip camera with better low light capabilities, so I've never had to compensate noise in post, so unfortunately I'm not the best person to ask. Others on this forum have a wealth of HVX low-light expertise and if you search the forum you'll see dozens of posts about how they've dealt with it.
Leonard Levy November 11th, 2007, 03:23 AM The best single thing you can do is lower your shutter speed.
In strong movement you can get some subtle ghosting, but generally I find it preferable to lots of noise. I often shoot at around 1/36 sec and have shot at 1/24th when I need to with no terrible consequences. Do your own testing to see when and if the blur bothers you. I've never had a complaint and I do it all the time.
Also Try to get your black level to a true black. If you stick with SD Norm or HD Norm you won't crush your blacks with the Ped at -4. In fact that's the correct setting to get a capped black to 0 IRE. You are already on the right track at -3.
Using Black Press or Cine V is just a way of crushing the blacks and becomes a question of taste. i don't like the extreme contrast so I don't do it. You can probably get a similar result by dropping your Ped below -4 so you are burying shadow and noise detail.
Panasonic just didn't set their Ped numbers properly for setup at "0" so actually -4 should been called "0", though it differs with some Gammas a bit.
TingSern Wong November 12th, 2007, 11:02 AM I am now testing NEAT VIDEO (an After Effects Plugin) on one of my noisy clips. Well - I would say "Holy Cow!". This is unbelievable. The quality after getting the output is simply ... Heh, you guys owe it to yourself to download the demo and test it out first. I am running the PRO version.
URL - www.neatvideo.com
Bill Edmunds November 12th, 2007, 03:47 PM I am now testing NEAT VIDEO (an After Effects Plugin) on one of my noisy clips. Well - I would say "Holy Cow!". This is unbelievable. The quality after getting the output is simply ... Heh, you guys owe it to yourself to download the demo and test it out first. I am running the PRO version.
URL - www.neatvideo.com
No Mac version?!?!? In this day and age, you've got to be kidding me. Too bad... as it looks really good.
TingSern Wong November 12th, 2007, 08:04 PM Too bad, then. Even then, I was hoping they can come out with a filter for EDIUS instead of After Effects :-). In the end, I suppose I will use whatever is available first ...
Ian Stark January 16th, 2008, 03:16 AM I've just chanced across this thread (I generally hang out at the XL2 and Vegas forums here at DVi) but I thought Bill and others would be interested to learn that a Mac version of Neat Video is being developed right now, according to their FAQ here : http://www.neatvideo.com/qna.html#GQ3.
How long this has been in development, or when it is die to be released, I couldn't tell you, but I'm sure they could.
Doesn't look like Edius is on the cards though.
I have used an older version of the plug-in in After Effects and I have tried out the demo in Sony Vegas and it is quite remarkable how good the results are, even using the presets. Beyond that, the parameters you have control over are extensive and yield excellent results.
BUT . . . learning how to get it right in camera will save you a lot of render time - this plugin is VERY intensive and render times on my blisteringly fast quadcore are around 8 to 10 x original footage duration.
Hope this helps.
TingSern Wong January 16th, 2008, 04:00 AM I checked with Neat Video developers ... and they did say an EDIUS version will be on their cards as well .... although they didn't put a timeline into it. I am not holding my breath for that - I use the version they develop for Adobe After Effects right now ... rendering times are slow - no doubt - but, heck - you only run noise reduction ONCE ... on a given clip, right?
Ian Stark January 16th, 2008, 04:26 AM That's good news - I saw your Edius/Neat Video thread on another forum somewhere (sorry, can't recall where!).
I had an interesting situation last night where I had a 15 minute unbroken clip of an awards presentation that was shot in very low light. I sampled the noise in an early frame and got a really good fix so I set it running ready for me to check it this morning. Bizarrely, the noise seems to creep back in through the clip, presumably as the noise conditions change (although the camera is pretty much fixed in one place and I can't see any discernable changes in light). By the end of the clip it was just as noisy as though it hadn't been treated. Weird.
I guess I will have to break the clip down into shorter segments and render them off one at a time, with noise sampling done afresh each time.
Even so, the results in the early part of the clip are astonishing.
TingSern Wong January 16th, 2008, 04:41 AM You might have to cut the clip into several portions and run NEAT VIDEO's profile tool against each portion to optimise its parameters for noise reduction. I suspect the light might have got lower towards the later part of the recording - thereby, causing your camera's gain to increase (if you set it up on AUTO).
I use HVX202 - and was pushing maximum gain (+12dB) and maximum aperature and 1/25 sec shutter - filming inside a Nepal's Buddhist monastery. The results I got from Neat Video was nothing short of astonishing ....
Ian Stark January 16th, 2008, 04:55 AM Yeah, good advice.
I think I may have pinpointed the cause of the problem - a couple of times people walk in front of the camera and on two occasions the camera is turned to face the audience to get cutaway footage. I think Neat Video may have lost its fix as the noise gets noticeably worse after these points.
As far as I remember I think the gain was fixed at +6dB, possibly 12, but definitely not on auto.
Intriguing!
I'm very envious of your visit to Nepal. I've travelled extensively but that's one place I would love to viset. There and Tibet.
TingSern Wong January 16th, 2008, 10:16 AM Ian,
To whip up your appetite for Nepal (I have gone there more than 10 times already) ... the latest photos are posted in this url -
http://wts.fotki.com/nepal-2007/
Enjoy them ...
Don't quite like Tibet - very arid, boring landscape. Was there for 4 months - as part of the Singapore Latin American Everest Expedition to the North Face of Everest.
http://www.everest.org.sg/
Dan Brockett January 16th, 2008, 11:11 AM Hi all:
You can also check out the new NR capability of http://www.dvfilm.com/MXFX/index.htm
Unfortunately they have not yet developed the NR in the Mac version yet, but they say that they are working on it. The NR on the PC version looks pretty effective, I saw some frame grabs on another thread somewhere.
Dan
Ian Stark January 19th, 2008, 03:41 AM Great stills! My appetite is duly whipped up!
Thanks for posting the links.
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