visceralpsyche
Well-known member
Very soon!
It's done actually, but I want to finish the Cine-D LUT as well so I can send them out as a pair.Cheers,
Paul
GH4 GH5 Owner / User Reports
- Thread starter ROne
- Start date
It's done actually, but I want to finish the Cine-D LUT as well so I can send them out as a pair.Cheers,
Paul
Bern Caughey
Veteran
Paul,
I've never used VLog-L so may be off base, but I'm guessing it may look better if overexposed a stop, or more, in which case it might be good to include exposure compensated LUTs both for processing & monitoring, for those users who are LUTCalc challenged.
Best,
Bern
I've never used VLog-L so may be off base, but I'm guessing it may look better if overexposed a stop, or more, in which case it might be good to include exposure compensated LUTs both for processing & monitoring, for those users who are LUTCalc challenged.
Best,
Bern
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visceralpsyche
Well-known member
No worries, a monitor LUT will be included which precisely matches the main post-production LUT
I'm already using it in camera.Actually, the optimal way to expose for V-Log (and profile really) is ETTR. Set zebras to 80% for the V-Log profile in camera and they will show you the clipping point. Stay just below that and you'll have optimum exposure and maximum dynamic range. The stills on the last page are all shot ETTR. Zebras stay accurate even with a monitoring LUT, so it's the easiest way to judge.
Cheers,
Paul
Peter Berry
Well-known member
Wow!!! An epic workaround for the Canon T Smart adapter as well - perfect! And it stays "fixed" on removing lens with power off and re-mounting.
Thank you, kind sir!
Peter
joe12south
Veteran
Don't assume that the 400mbps codec will look better. That extra bandwidth is going to mostly go to storing each frame (i.e. making editing easier) not yielding better quality. Remember, the all-i codec looks *worse* on the GH4.
Ben Scott
Veteran
I've no experience of the GH4 so don't know what has gone before but all other things being equal an intra-frame codec is going to have a better image than a long-gop one if it is given the necessary extra data to record those frames properly. Did the GH4 have this data bump when it offered All-I recording as well?
Similarly a log recording mode is only of any use/benefit if there is enough information to fill the log container. 150mbs is what, 18.8MBs, compared to the 50MBs of the promised 400mbs update. At 10-bit as well, that is a setup that could yield a great and robust log image.
At the moment having it there is more of a marketing gimmick in my opinion and there is probably more mileage to be had in shooting in the other gammas while 150mbs is the only thing on offer.
Similarly a log recording mode is only of any use/benefit if there is enough information to fill the log container. 150mbs is what, 18.8MBs, compared to the 50MBs of the promised 400mbs update. At 10-bit as well, that is a setup that could yield a great and robust log image.
At the moment having it there is more of a marketing gimmick in my opinion and there is probably more mileage to be had in shooting in the other gammas while 150mbs is the only thing on offer.
filmguy123
Veteran
What do you mean set zebras to 80% for vlog and they will show you the clipping point? Why not 100% zebras for vlog (or any profile?) and then just make sure nothing is clipping unless you don't care, and use histogram to judge the rest?
Thanks for helping me understand!
Thanks for helping me understand!
Ben Scott
Veteran
Because if you are trying to map a correctly exposed log image into a rec709 or rec2020 workspace there are constants that aid that mapping, such as knowing where 90% reflectance should sit in the log image and knowing where 18% grey should sit in order that when the log image is transformed to the other colour spaces it is done correctly. Knowing this allows you to expose your shots properly without having to hope for the best.
For example with S-log3 on the FS7 Sony state 90% reflectance should be exposed at 61%. Testing from a lot of people showed that to be wildly optimistic and that targeting 75% via zebras for 90% yielded a constant usable and correctly exposed clean image.
LOG profiles are exposed differently than non-LOG profiles. For example when shooting Panasonic V-Log L the correct exposure for a 90 percent reflectance white is 61 IRE, where it would be closer to 90 IRE for non-Log profiles.
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It always seemed that people were exposing 90 percent white higher to get a cleaner image ( especially in the shadows ), where the 61 IRE setting was specified for maximum dynamic range.
Ben Scott
Veteran
Long story short, but Cine-EI mode's labelling of its native iso as being EI2000 was ummm, 'optimistic'. So you need a constant system of controlled exposure above what Sony were stating was needed. An FS7 in CineEI mode and A7sII at the same ISOs would yield quite different brightnesses. So yes it for a cleaner image but really just to correct for Sony's fib.
JonsMovies
Active member
Something I haven't seen discussed yet, but I'm hoping someone with the camera can answer. How does the 1080p on the GH5 compare to the GH4? As we know, the GH4 (like the GH3 before it) does not properly downscale the sensor to 1080, creating lots of aliasing and a vastly inferior image to the 4K one. I'm hoping the GH5 corrects this issue and we end up with 1080 quality closer to that of the GH2/C100 so not everything needs to be filmed in 4K to get a great image out of this camera.
visceralpsyche
Well-known member
As others have mentioned, log is recorded differently, but for the purposes of knowing the clipping point, at 80% on the zebras using V-Log in the GH4 and GH5, the brightest values are being recorded by the camera. You have filled the pixel well, so to speak, so everything higher than that is just clipped white.
You can test this out if you have V-Log on one of your cameras. Set zebras to 80% and then deliberately overexpose a part of the image, noting what parts show zebras. Bring that clip into your editing software and examine the clipped areas after normalising the V-Log using a LUT or manually. You'll see they are actually clipping over 100% IRE normalised.
HTH!
Paul
joe12south
Veteran
The GH5 uses the same new scaling methods to sample the entire sensor for both 4K and 1080P. You will see very little difference scaling down in camera vs scaling in your NLE.
joe12south
Veteran
Do the math for a 4K, 10bit 4:2:2 image - 400mbps isn't much bandwidth if you store every single frame. As a point of comparison, ProRes clocks in at over 800mbps. It's likely that 400mbps all-i is going to be comparable quality to 150mbps long-gop. It would be nice to be wrong, and it's possible it might be somewhat better, but I don't think people should be counting on it.
joe12south
Veteran
It's V-LOG L, not V-LOG, and in that important distinction lies your answer. The GH5 records up to 12 stops of DR. Varicams record up to 14. In order to use the same curve for both (god knows why this matters) the V-LOG L signal fits in the bottom 12 stops. That's why 100% white peaks at 80% IRE.
Ben Scott
Veteran
I'm not counting on it. I'm just discounting using log until that comes along and the container is more filled. As I said this is my nice little B-camera for when I don't want to use the main one. Plenty of times when log is not the best way to shoot on a camera like this and my one shoot so far Cinelike D was fine.
Red R3Ds are smaller in size than Pro Res too. XVAC-I from an FS7 smaller than the same pro res files it spits out too for very little if any gain in IQ. Bitrate isn't everything if you are comparing apples to oranges.
JonsMovies
Active member
That's fantastic news and yet another reason to upgrade from the GH4. Thanks a lot!