FS7: Compression artifacts: XAVC-I "feature", or my FS7 malfunction?

For some reason, I thought your main conclusion was to use SLOG-2 because it gave you more headroom before clipping?

In this recent blog post, Chapman recommends exposing for the mid range and "... in most cases the highlights will take care of themselves. "

http://www.xdcam-user.com/2017/08/beware-exposing-to-the-right-with-log/

If you shoot with SLOG 2, expose for the mid range, and try to avoid clipping the best you can (graduated ND filters, recomposing the shot, etc..), shouldn't you be all right?
 
Yep - S-Log2 is definitely easier to get it right. And exposing for middle gray rather than ETTRing (with +2 stops some people follow blindly) should indeed be the safest way...

Piotr
 
You could have saved yourself a lot of time by just watching one of my training videos or reading one of my books. Alister's blog is nothing more than a paraphrasing of the advice I've been giving for three or four years. If you want to get good results with S-LOG, set Zebra2 for 75% and allow just a hint of zebra on the brightest reflected whites -- and then grade properly in Resolve using the correct LUT (not an NLE or Catlaylst Browse). I prefer S-LOG2 because if it's better highlight handling, but in many scenarios S-LOG2 and S-LOG3 can be graded to look exactly the same. It's just that simple. This is not rocket science and there's no need to keep reinventing the wheel. All of this has already been figured out by myself and plenty of other people who know what they are doing. So much time wasted.
 
Dear Doug, why do you think that my work - which turns out to bring similar results to yours - is time wasted? Because I don't charge for it? But hey - you should welcome and endorse my efforts as they confirm your findings, free :)

Best Rgeards

Piotr
 
Your time is wasted because it has taken you hours of work to come to the same conlcusions that other people have aldready figured out. That is why I do not hesitate to spend money on training from other people, particluarly software, who know more about a given subject than I do. That is the whole point of training and education. This is why we have schools, universities, non-fiction books, documentaries, etc. -- so we don't have to waste our own time doing work that someone eles already did for us. You could have spent that time actuallly producing finished work. If someone doesn't understand that time is money, then they aren't going to be successful in professional video production, that is for sure. But you might just be doing it for the fun of it, and that is fine too. Enjoy doing your experiments.
 
Doug Jensen said:
Your time is wasted because it has taken you hours of work to come to the same conlcusions that other people have aldready figured out. That is why I do not hesitate to spend money on training from other people, particluarly software, who know more about a given subject than I do. That is the whole point of training and education. This is why we have schools, universities, non-fiction books, documentaries, etc. -- so we don't have to waste our own time doing work that someone eles already did for us. You could have spent that time actuallly producing finished work. If someone doesn't understand that time is money, then they aren't going to be successful in professional video production, that is for sure. But you might just be doing it for the fun of it, and that is fine too. Enjoy doing your experiments.
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Keep up the great work, Doug!

I've rented your FS7 videos and your Resolve videos and they're a bargain at double, triple or quadruple the price. Interestingly enough, on one my recent projects I graded in Resolve based on your training and in the end decided that a talented colorist I know would be able to help me get even better results, but even in spite of that, the knowledge I gained from your training video made it much easier for me to work with this guy as I now have a bit of a clue as to what he was doing and how we could work together.

Thanks again!

Tim
 
moldcad said:
Jesus...
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I'm glad you brought him up. I was speaking to Jesus the other day and he agrees with my exposure recommendations and that S-LOG2 is superior to S-LOG3. He said that if everyone would just follow that advice it'd save him a lot of time listening to people praying for a miracle to save their footage in post.

@Vintegreo
Thank you, I appreciate the comments and I'm always glad to hear that somehow I've helped other people.
 
No Doug - I "brought Him in" (as you put it) because at that point, I felt helpless and astonished by the ego of a person who seems to really believes he knows everything best, even though earlier in this very thread the same person claimed he didn't find anything wrong with XAVC-I rendering of the scene I uploaded as an example of the problem being discussed. Yeah, I realize my own ego is also strong (too strong perhaps) - but I'd never go as far as being dismissive about other people's effort to investigate and understand all by themselves the phenomena I happened to have investigated and explained elsewhere, even if I had written a successful book / video about it :)

Your ego even prevented you from noticing and endorsing with well-deserved satisfaction that my findings are in agreement with your own, while rather seriously questioning those of your "competitor" Alister Chapman :) Because it's been Alister whose 1-2 stops S-Log overexposing "recipe", without enough care for what's really happening in the highlights, has dominated video community for quite some time...

I truly wish you success with selling the fruits of your expertise and hard work, Doug - but let me decide by myself whether to rely on educational sources from someone else, or try to find out and understand things using my own efforts. Stating that I'm losing my time because you have said/wrote something earlier/better is not very courteous in my book :(

After the initial frictions between the two of use some time ago (on this forum as well as on the other one), there was a time when you started treating me more friendly which I really appreciated, as I really esteem you highly, Doug - let's keep it that way, shall we? Best Regards

Piotr
 
moldcad said:
No Doug - I "brought Him in" (as you put it) because at that point, I felt helpless and astonished by the ego of a person who seems to really believes he knows everything best, even though earlier in this very thread the same person claimed he didn't find anything wrong with XAVC-I rendering of the scene I uploaded as an example of the problem being discussed. Yeah, I realize my own ego is also strong (too strong perhaps) - but I'd never go as far as being dismissive about other people's effort to investigate and understand all by themselves the phenomena I happened to have investigated and explained elsewhere, even if I had written a successful book / video about it :)

Your ego even prevented you from noticing and endorsing with well-deserved satisfaction that my findings are in agreement with your own, while rather seriously questioning those of your "competitor" Alister Chapman :) Because it's been Alister whose 1-2 stops S-Log overexposing "recipe", without enough care for what's really happening in the highlights, has dominated video community for quite some time...

I truly wish you success with selling the fruits of your expertise and hard work, Doug - but let me decide by myself whether to rely on educational sources from someone else, or try to find out and understand things using my own efforts. Stating that I'm losing my time because you have said/wrote something earlier/better is not very courteous in my book :(

After the initial frictions between the two of use some time ago (on this forum as well as on the other one), there was a time when you started treating me more friendly which I really appreciated, as I really esteem you highly, Doug - let's keep it that way, shall we? Best Regards

Piotr
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Well come on.. Mr Chapman didnt invent the idea of over exposing and "bringing" down in Post.. film DP,s have been doing that for decades .. plus yes it is empirically a way to raise the noise floor.. that is just a scientific fact .. you do seem to have endless problems .. sorry to say but logic would point to user error.. or your camera ,computer, hard and soft ware have some problem..
 
OK, I'm shutting up on this subject. Thanks everyone for their input, and sorry for wasting your time or getting on your nerves.

Piotr

PS. Just a reminder before I definitely drop the subject: please remember that I'm one of the first FS7 shooters / Resolvee user who has been grading all his stuff for HDR. Maybe this little detail will ring your bell, everyone who thinks I've been seeing problems where there are none, or making user errors all this time?
 
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Doug Jensen said:
If you want to get good results with S-LOG, set Zebra2 for 75% and allow just a hint of zebra on the brightest reflected whites
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+ 1 on that. Many, many shooters and graders working with S-LOG 2 and 3 with virtually no issues. As Doug says it's really not rocket science. BTW I get the same results grading whether it is Long GOP or I-Frame so that is not the issue. Lot of people trying to help you here but for some reason you are still stuck in 1st gear. If others can do and get decent results you can. I can only conclude and assume that something is going wrong in your workflow regardless of what equipment you are using Piotr.

Chris Young
CYV Productions
Sydney
 
May I note, Sir, that most of the "others" you mention can't even see anything wrong in my examples?

Which would mean it's rather a "how high your expectations are" issue... Mine are very high, and my work is all about quality not quantity.

With all due respect,

Piotr (stuck in the first gear :))
 
I realize you're all fed up with this thread and my "revelations", but at the same time I'm very curious what would you make of yet another fact/observation I made lately, so here I go:

As some of you guys may remember, I've been using Resolve for grading and rendering my Log footage (not just from my FS7, but also GH5) in HDR. Even though I'm not lucky enough to have access to a true, professional HDR reference monitor - my 49KS8000 Samsung SUHD TV handles well over 1,000 nits (in fact - within a no more than 25% of the total screen area - I can clearly see difference in brightness and color between said 1,000 nits and as much as 1,400 nits, so - given that my monitor has recently been calibrated again - I hope I'm good to go with my HDR10 (PQ) projects set for 1,200 nits target max brightness). But with my last project, I was asked for an SDR version; it also so happened that I re-used some of my older FS7 clips, recorded internally and using the (offending in HDR) XAVC-I codec...

So I set the UHD@50p project properties for the old good Rec.709 on output, and voila! - all the banding, tearing and blockiness in the sky that haunted me for so long with the XAVC-I clips are all gone!

No - what do you guys make of it, I wonder? ! Could it be that the inherent quality of the Sony XAVC codec (even in its Intra-frame version) is simply not high enough for successful HDR production? Or – should it be good enough (with only the obvious disadvantage of the bitrate being lower than my Inferno's Prores or DNxHR, which both give pristine quality PQ imagery), but my unit’s XAVC encoding chip needs some calibration, after all? Thanks,

Piotr

PS. At least I now understand (and believe) those of you who (like Doug) never found anything wrong with the clips I uploaded for you to inspect, which showed those awful artifacts here mainly in the blue sky areas :)
 
JCummings said:
C'mon Piotr, we all want to check out your work!
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OK - even though I believe I did already explain to you Guys that video (shooting, editing, grading etc.) has never been my main profession (see here: www.linkedin.com/in/piotr-wozniacki-94922120 ) - here is my background again.


For many years I had edited classical music concerts (you can find the DVDs I authored here: http://www.castellogt.pl/plyty-wydane ); of course I also produced BDs with all those events - but since it's so much easier to sell DVD than BD, only the former have always been printed while BDs with the original, FHD versions of the coverage I only burned in very limited quantities). I always was one of the camera crew for those events and some of them I also DP'ed.

At that time (in the years 2008-2015) I didn't use Resolve; Sony's Vegas Pro was my NLE and I must tell you it was a real pleasure for me as a true music lover to set up a multi-camera project in Vegas, display all cameras in the MC view on a large monitor (had to be a 50" FHD plasma so that - even with 6-10 individual camera windows on it - those windows were still big enough for me to see details), hit 'Play' and let myself get submerged in that audio-video experience! When I had a "good day" (right mood, nobody/nothing disrupting my work), I didn't even have to watch my waveforms; with the large enough picture of each camera displayed simultaneously and synchronized perfectly (a subject for another discussion :)) with the loud enough sound of those beautiful master-pieces - I did my cuts on-the-fly, picking what I considered the best camera view to be shown at s specific moment of time within each piece duration... As I said: cutting my MC music videos has always been a true feast for my senses...

My life has then taken an unfortunate course after I couldn't postpone a serious surgery on my neck spine any longer (actually, 2 unsuccessful surgeries) - and I do not produce my classical music videos any more :(. I also switched from Vegas Pro do Resolve, and UHD HDR10 grading has become my new passion... But I do miss my multi-camera, live classical music concerts cutting experience, so the day will come when I'll try to re-create my Vegas Pro workflow in Resolve. I realize DR's strength is not in MC cutting but grading and creative correction of color, so it may as well prove the workflow is not going to work in Resolve as good as it used to in Vegas Pro - but the main thing will never change:

- if you have a good musical ear, cutting your music videos can be a great, creative experience!

So at the moment, everything "video" in my life boils down to my new passion which Resolve has made possible for me (UHD grading for HDR10) plus what I've always been doing before - classical music events (both acquisition and post-production - just at a much smaller scale than before). Unfortunately, my position with CastelloGT (the Company I used to create and publish classical music DVDs/BDs for) precludes any kind of sharing the contents of those recordings, of which we sold a lot, in any unauthorized form. And no wonder - it's been CastelloGT who invested in organizing a renowned classical music yearly event at the Polish Royal Castle of Wawel at Kraków; they also spent considerable money on wages for the internationally renowned, first class musicians whose performance we recorded (both orchestras and soloists) - so I hope you understand. Of course, I can help any of you interested to buy some of our published DVDs.

I hope I've satisfied your curiosity - thanks everyone for their interest :)

Piotr
 
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