View Full Version : Muddy Footage GY HM600
Tim Gauthier March 25th, 2013, 01:26 PM Hey, anyone else with the GY HM600 feeling like their footage looks muddy? Even with what feels and looks on camera to be a good focus my shots feel very muddy after the fact. I am editing in FCPx but even just viewing the files they look blurry. I am shooting at 180° on 24p at 1080. I may try cranking up the detail in camera again and see if that helps but it is bugging me a little bit. The shot of the royal crest on the castle was pin sharp in the Viewfinder (eyepiece not LCD screen).
https://vimeo.com/62622917
Noa Put March 25th, 2013, 02:15 PM Do you know what your average f-stop was? Softness in daylight bright footage could be the result of diffraction when no nd is applied and the camera needs to close down the iris completely to compensate, which it can't.
Battle Vaughan March 25th, 2013, 02:21 PM Agreed, the colors are muted, the sharpness isn't what you would expect, and the images seem somewhat dark and muddy.
Might be you want to tweak the camera setup, see instructions starting at page 92 in the manual. You can increase contrast, set the black point, arrange color balance, sharpening, etc. to your taste.
Might also check your FCPx settings, you might have inadvertently set a default for, say, broadcast limits (which constrains the density range of the image to suit broadcast requirements) or some such.
Best wishes!
Jody Arnott March 25th, 2013, 02:42 PM Not sure if this helps but there are some recommended settings in this document:
http://tech.ebu.ch/docs/tech/tech3335_s07.pdf
I don't have the experience to be changing the contrast/colour/knee, etc, settings myself so I used those recommended settings and haven't had any issues.
Tim Gauthier March 26th, 2013, 10:56 AM I am using those settings Jody, I can not remember my exact IRIS, but I have been trying to keep it under 5.6
I know i had the Gain on 0 and the ND at 1/64, however that sometimes does not appear to be enough, do you suggest using negative gain or should I increase framerate ?
Tim Gauthier March 26th, 2013, 11:07 AM I had detail on -7 I suspect that would be the problem. I have put it at around +3 now, I believe it was -7 due to the article, I am going to reread that and make sure I didn't do it incorrectly.
Also, not able to do a negative gain (makes sense) so I will possibly need to start using my Polarizer outside.
I highly suspect that the -7 detail is what caused this issue, as I do not remember the camera being that muddy previously. The sun is already setting, so I am going to head out right now and see if I can snag a few handheld shots from the Citadel.
Jody Arnott March 26th, 2013, 02:57 PM I am using those settings Jody, I can not remember my exact IRIS, but I have been trying to keep it under 5.6
I know i had the Gain on 0 and the ND at 1/64, however that sometimes does not appear to be enough, do you suggest using negative gain or should I increase framerate ?
I use -6 gain unless I'm in low light. I find that even 0dB is slightly grainy when lighting isn't ideal but -6 is extremely clean. To achieve -6dB gain you need to set "extended mode" in the settings.
I also have my detail set to -7 though, so I'm wondering if that's what is causing the grain. Let me know how +3 detail is for you.
Tim Gauthier March 31st, 2013, 12:45 PM Thank you very much for the -6 gain trick, that helped a lot. Also I pumped it up to +3 detail and I find that it aliases a little bit, but is more crisp over all which I prefer. I took some footage but since I'm at the S.O.'s family for easter I haven't really bothered to put anything up!
Tim Gauthier April 12th, 2013, 05:44 AM This was all shot with -6dB, and the stuff where we still had decent light looked ok, but I definitely got quite a bit more noise as the light dipped away. This was apparent BEFORE I graded but definitely obvious after. However I think it all still looks ok.
I shot with detail at +3.
Any suggestions on what I can do with my settings etc? I was running for most of it so I could stay in the right IRIS.
I feel like i'm still not quite getting everything out of the camera, also realizing just how much I have forgotten.
Erfurt Petersberg Rainy Evening Graded on Vimeo
Jody Arnott April 15th, 2013, 02:46 AM I've noticed my HM600 produces a very grainy image in low light even at -6dB gain also. So I'd also be interested in any information about any different settings that may help with this.
Tim Gauthier April 27th, 2013, 06:08 AM and so I continue playing with the camera, I would say this is a HUGE step forward in quality from what I had originally. I am using the Alex4D unsharp mask and that has made a difference as well (thought not necessary I do like how it looks).
The big trick was lowering the green matrix a bit, and colour grading the footage afterwards.
The Forest on Vimeo
Christopher Young April 28th, 2013, 08:00 AM Negative gain reduces the dynamic range of you camera so it should be used judiciously. Check Alister’s site for a fuller explanation. The less the dynamic range the flatter looking your image will be.
Why using negative gain can be bad, unless you have an F3. | XDCAM-USER.COM (http://www.xdcam-user.com/2011/07/why-using-negative-gain-can-be-bad-unless-you-have-an-f3/)
Chris Young
CYV Productions
Sydney
Tim Gauthier April 29th, 2013, 03:17 AM If I understand correctly that affects the low end of the image blacks and such, or would that limit in the dynamic range affect the high end? So far in my footage I have not actually found any noticeable limit in how much dynamic range I have.
Christopher Young April 29th, 2013, 12:24 PM Hi ~
If you switch in -6dB you are reducing the dynamic range by one stop. You are effectively moving the entire output from the sensor down by a stop. You are correct negative gain makes for less sensitivity in the dark areas of the image and in turn the image will appear to have less noise in the low light areas because you have effectively crushed visibility in the blacks. Conversely though your maximum levels are now down as well. In effect the range you have to reproduce the image is down by one stop. Example, in a camera with a ten stop range you have lost ten percent of its dynamic range. Sadly the less dynamic range your camera has to operate in makes for a flatter less vibrant looking image.
Chris Young
CYV Productions
Sydney
Tim Gauthier April 30th, 2013, 01:54 AM fantastic, thank you :)
Is that something you personaly noticed in my footage or just a warning based on reading the article? From my experience grading this footage, running in the wdr mode with the -6dB i've not seen any loss of range.
I know in my earlier footage with 0dB or +6dB I had very little detail in the low end and low midrange tones, it was noisy and just had zero detail to pull out when grading. I do not know if it is because I switched to WDR or if it is the positive gain but it definitely gives me a cleaner range of image now. Thank you for giving me something to play with
Christopher Young April 30th, 2013, 12:28 PM Hi ~
Experienced it quite often. You can see it visually and on a waveform monitor. I pointed you to Alister's site because he explains it as well as anyone else.
We shoot a lot of network TV football where the lighting can range from intense sunlight to pitch dark shadows in a lot of the stadiums, especially late in the day. Exposures can range from about f16, virtually closed iris, in the direct sunlight to about f2.8 in the heaviest stadium shadow areas. Sometimes we will run - 3dB to keep the exposures from going right down to f16 in the sunlight. Staying on 0dB we can risk over exposure in the sunlight even at f16 so would have to swing in ND filters on the cameras to avoid that. Switching ND filters in and out on a fast moving game is not a good look for the viewing audience. We know there is a trade off but basically it means we can cover the whole exposure range without filter swinging. Another thing is lens diffraction, loss of resolution at the higher numerical f stops. Running negative gain helps us to keep closer to the sweet f stop range on the lenses of f4 to f11. You win some you lose some :)
Chris Young
CYV Productions
Sydney
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