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Zak Forsman

V-Log L captured in 8 bit vs 10 bit

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Thanks. I don't think the lens has anything to do with it b/c I've tested some grey/beige walls with the 12-35 and the macroblocking is there, but I think the shots in Chicago were high contrast which hides it pretty well.

I've done some more testing today and have found that the Varicam LUT is just the worst in regards to hiding the magenta/cyan blocking. Something about that curve is just not right with the GH4's V Log. Film Convert seems to hide it pretty well. Exposing to the right by a stop or so also helps. Thank God faces aren't lumped into the cyan/magenta problem. They seem to be fine. I would just avoid big walls of light beige/grey, or yellow. Pure white and dark grey are fine.

So what's the major differences in V-Log Paid and V-Log Free?

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EOSHD Pro Color for Sony cameras EOSHD Pro LOG for Sony CamerasEOSHD C-LOG and Film Profiles for All Canon DSLRs

Even Cinestyle had none of the degrading qualities of V-Log here. S--log2 doesn't, C-Log doesn't, all in 8bit with even lower-end more-compressed codecs. 

After investigating (cool word for pixel-peeping) V-LOG on the deep image quality level (deep meaning it's way less significant for normal viewers vs. me) what I see is:

1 -More noise, shadow and midtones. Not just more, but worse looking noise pattern (coloured/blotchy)

2 -Banding, colour banding and posterization everywhere especially in the area between shadows and mids, 30-40IRE-ish

3 -A colour shift I can't remove for the life me. Neutral/Cine-D are more natural/accurate.

4 -Increased highlight DR by about a stop. Actually sees more into the highlights. 

5 -Slightly less shadow DR (clipped earlier, more noise, colour posterization/artefacts)

(benefits of v-log are in Bold)

Tested enough to decide shooting CinelikeD unless Panasonic or someone else fixes V-Log. I couldn't care less about the slightly less highlight clip.

 

Yikes. After all this time, and supposed money, Panasonic has put into it and it's really this bad? I have a hard time believing it.

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it's just day two, slog2 also have ugly noise at +0 ev

I like the color from vlog already, doesn't have orange/plastic looking people of Cine D

 

but I do think an external recorder is what vlog really need

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I think the real value of Vlog lies in the fact that you can now, with a properly lit set, shoot with this camera and come away with footage, that rivals very expensive cine cams, which you could not rent for a 3 week shoot, for the price of several GH4's ...it may not be a good run & gun/walk around profile, but it's just another element added to an already pro packed camera...making the GH4 ever more relevant...Apple should learn from this...

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I think the real value of Vlog lies in the fact that you can now, with a properly lit set, shoot with this camera and come away with footage, that rivals very expensive cine cams, which you could not rent for a 3 week shoot, for the price of several GH4's ...it may not be a good run & gun/walk around profile, but it's just another element added to an already pro packed camera...making the GH4 ever more relevant...Apple should learn from this...

This is true. The highlight rolloff is insane. Very cinema camera-like. I think as long as a neutral surface isn't prominent and in focus, or the focal point,it's a real hero.

 

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This is true. The highlight rolloff is insane. Very cinema camera-like.

Not wanting to be nitpicky, but when I saw your video, I thought the very opposite (see screenshot).

vlcsnap-1.jpg

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Not wanting to be nitpicky, but when I saw your video, I thought the very opposite (see screenshot).

vlcsnap-1.jpg

That shot is a pretty extreme DR example. Sun blasting the pavement. It's also 1080 at 96fps which is the worst in regards to overall res/detail. Look at other shots and you'll see a difference. Trust me I've been shooting with the GH4 ALOT since it was released and the highlight rolloff is much improved.

 

AdamsSt.jpg

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Aaron...I think you and Zak are already getting amazing footage with this profile, especially how recently you got it...Shian on PV has also come up with some beautiful shots...it will take time to nail this and Shian correctly predicted that most people will hate it, but he loves what this does for the GH4...it will only get better with time....

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So far I have heard no mentioning of WB in combination with V-log …it has a huge influence and I actually suspect there is a bug related to WB an V-log causing the macro blocking artifacts.

I did some tests with the following settings: WB 4000K and 4200K, Natural vs V-log, Shutterspeed 30, ND 1.2, Exposure 6400, everything in All-I 25fps 1080. Shots where 2 stops underexposed. I used V-log to custom (own brew) on the Vlog clips.

As you hopefully can see in the picture, the noise pattern of the Natural clips is identical in both 4000K and 4200K. The only difference is the color.
The noise patterns (macro-blocking) of the V-log clips are completely different for each Kelvin value. Only when you reach the top values (±9000 and up) the patterns become more identical.

It is as if the WB adds ad-random posterization to V-Log clips as if the white balance is part of "V-log space". I do not know enough about WB and how it works or should work but to me this looks and feel like a bug.

If it's not a bug …I would like to know how to set the WB because even Custom has a a different noise distribution each and every time you set one. The second picture shows this. Each of the four custom settings give different noise patterns, even though the conditions were the same at the time of creation. The two at the bottom look quite similar but that is luck. To be clear these are not four frames out of the same clip. The macro block islands change shape but stay where the are …and their position and number are completely random as far as I can tell.

Hope someone can either confirm it's a bug or tell me how to use WB properly.

Thanks.

Vlog_WB_pattern.jpg

Vlog_WB_pattern2.jpg

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I was very disappointed with the noise, it makes me feel like i am in a time warp editing footage from my Canon XL1 in 2006. So I tried to tweak/ max out the settings we have available in V Log. I raised NR to +5 and i.Res to High. This immediately killed the noise in the lcd screen and evf. I have looked at the footage and it seems to help. I know it is established that pumping up these settings don't help the image in the long run, but I wanted to see if the payoff was worth it.

For any of you GH4 pros with more experience, what exactly am I sacrificing by raising these settings so high?

(I am also struggling with exposure for VLog, any tips on what I am doing wrong in this shot would be helpful. 'Twas a sunny day, lady facing the sun.)

Settings Test Vlog.png

 

Settings Test Lut.jpg

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I was very disappointed with the noise, it makes me feel like i am in a time warp editing footage from my Canon XL1 in 2006. So I tried to tweak/ max out the settings we have available in V Log. I raised NR to +5 and i.Res to High. This immediately killed the noise in the lcd screen and evf. I have looked at the footage and it seems to help. I know it is established that pumping up these settings don't help the image in the long run, but I wanted to see if the payoff was worth it.

For any of you GH4 pros with more experience, what exactly am I sacrificing by raising these settings so high?

(I am also struggling with exposure for VLog, any tips on what I am doing wrong in this shot would be helpful. 'Twas a sunny day, lady facing the sun.)

Settings Test Vlog.png

 

Settings Test Lut.jpg

The exposure actually looks good. What did you use to convert V Log ?

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I was very disappointed with the noise, it makes me feel like i am in a time warp editing footage from my Canon XL1 in 2006. So I tried to tweak/ max out the settings we have available in V Log. I raised NR to +5 and i.Res to High. This immediately killed the noise in the lcd screen and evf. I have looked at the footage and it seems to help. I know it is established that pumping up these settings don't help the image in the long run, but I wanted to see if the payoff was worth it.

For any of you GH4 pros with more experience, what exactly am I sacrificing by raising these settings so high?

(I am also struggling with exposure for VLog, any tips on what I am doing wrong in this shot would be helpful. 'Twas a sunny day, lady facing the sun.)

 

Noise seems the most in magenta colours. Some LUTs seem to produce it a lot while others make it disappear. The main thing for exposure seems to be set zebra to 80% and wind back just a tad from there with either shutter speed or ND filter, ie. the same as I would do with a normal profile (except zebra would be on 100% for other styles). I use iRes standard, sharp -5, NR 0. But really it seems more to do with the interaction between LUT and overall colour of shot. There's something nasty going on with the pink jacket though. Almost looks 1080 bad.  

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According to a couple of long, rambling threads on DVX User, what I've gathered is that the GH4 has some sort of inherent problem with its processing that causes this magenta/green splotching/accuracy issue. Apparently, this problem is present in all the GH4's profiles to some degree, but the data pushing from encoding and grading from LOG hugely exacerbates it. My understanding is that these color errors occur at the processing level and before compression, so while 10-bit recording reduces compression and helps make the footage more pliable, it doesn't solve the underlying problem. 

I have to wonder if the G7 would experience this too. Its low-light processing seems to be much improved from the GH4's, and creates far less splotchy color artefacts. 

See the low light samples in this review: http://www.cameralabs.com/reviews/Panasonic_Lumix_G7/
Check out the comparison with the GH4 at 5:45: http://dslrvideoshooter.com/panasonic-gh4-vs-g7-video-review/
And Brandon's high ISO samples at the bottom of the page: http://www.dvxuser.com/V6/showthread.php?337827-g7-vs-gh4/page4

I wonder if they could improve the GH4's performance by offering the new NR algorithm as a firmware update or something. Maybe it's part of the underlying hardware or LSI. I don't know. But it reminds me of the G6's massive noise advantage over the GH2, despite using the same sensor (and actually reading less of it in video mode). 

After this V-LOG update, I had my heart set on upgrading to the GH4, but if the G7 is this much better with noise and $400 in the bargain, it seems like a no brainer. Shame, because I already have the batteries and whatnot from my GH3. :/

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I'm looking closely at the Blackmagic Micro Cinema Camera now because of this. Looks like I already have all the support gear I'd need for it minus a cage and rod riser of some sort. Wish it was 4K of course, but color and DR are more important to me. And I think I'll be more satisfied with the results. optional global shutter and i'm expecting better noise performance given the better cooling inherent in the BMMCC's design (compared to the Pocket). ...sorry for going off topic. 

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Yeah, I own a A7S and a GH4. And for the last week I am comparing the 2 camera's. Made a video, did not upload yet. 
Without V-log I would always choose the A7S over the GH4 because better color, DR and highlight roll off. But now with V-log. I do not know which camera I like the most. 
Ok a7s still has some more DR, and slightly better highlight roll off. But is also 1080p, no good slowmo options, crazy low battery life, stupid button and menu design against 4K, good slowmo and good battery and a body that is better all around. A7S II does fix some of those problems, but the pricepoint is killer.

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I'm looking closely at the Blackmagic Micro Cinema Camera now because of this. Looks like I already have all the support gear I'd need for it minus a cage and rod riser of some sort. Wish it was 4K of course, but color and DR are more important to me. And I think I'll be more satisfied with the results. optional global shutter and i'm expecting better noise performance given the better cooling inherent in the BMMCC's design (compared to the Pocket). ...sorry for going off topic. 

Same here. I actually pre ordered it, and then cancelled when V Log was released, and now wishing I hadn't cancelled. :grin:

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For anyone that has Magic Bullet Looks, I've been using 4 way color corrector as the first treatment on V Log instead of a LUT, or S Curve. For some reason it works really well and keeps the midtones in tact. Here I crushed the blacks and blasted the highlights in 4 way CC, then added M31 Rec709 LUT.

 

BarnM31.jpg

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