Re: S-Log w/ 1.31 Firmware PDF
 

I'm definitely interested in your experiments Doug and of course once I get V1.4 I will be trying my own tests, it has to be done after all.

But I do have to wonder if it is really possible to create an good in camera look that has 13 stops of DR? This not a reflection on the way you shoot Doug, just wondering if it really is asking for too much.

The problem of course being that if you take 13 stops and squash it in to the typical 7 stops that most TV's and monitors can deal with, it will look flat and it will almost certainly look un-natural as you are compressing the image. The issue with using a Log curve to do this is that the highlights are compressed, with S-Log everything above about 60% is getting quite strongly compresses and above 75% very highly compressed. Compare that to a cinegamma where the compression doesn't really start to get significant until you get to about 80% and on paper at least that suggests that with the log curve your going to struggle to get skin tones to look natural and bright scenes are going to look very flat.

While you can add in some negative black gamma to make the image look more contrasty, this isn't going to change the highlight performance and with no other way to modify the top end of the curve your kind of stuck.
Anyway, perhaps you'll prove me wrong Doug, but I'm not convinced you'll get a useful benefit using the log curve for your way of working. I think that the cinegammas are a good compromise between extra dynamic range over standard without the image washing out.

If you do choose to shoot log and grade, the advantage you (or the colourist) has is to be able to selectively work on parts of the image, so you can just bring the highlights down while leaving everything else intact, which is something that just can't be done in camera, not yet at least.

Re: S-Log w/ 1.31 Firmware PDF
 

Alister,
I'm curious why it is easier to spread out all 13 stops in post (back to 709) than in the camera itself. In my grading experiments with Slog I've been first de-logging using a curve which by itself would push the highlights into over exposure , then I'm adding a shadow highlight filter to additionally compress the highlights ( and also to finesse the shadows but that's less in need).

So technically why is it so much harder to achieve in camera? It would certainly be difficult to get the balance exactly right on set and maybe more dangerous. I assume that's kind of like what the cine gamma does already but not as well.

Re: S-Log w/ 1.31 Firmware PDF
 

The problem is that the settings available in the F3 don't allow you to make any changes to the shape of the S-Log curve other than a bit of black stretch which only raises or lowers the bottom of the curve. So your stuck with the same highlight handling.

In post you have much finer control over which parts of the image you adjust and by how much. A proper grading tool can work on very specific tonal ranges giving you much greater control than you could ever have or perhaps want on a camera. One issue is that if you start adjusting specific ranges relative to the others within the same image is that it can be very hard to un-pick that look if you later decide you don't like it. For me what I want is a neutral image so I can pick my look in post.
I'm working with F65's at the moment that have 16Bit linear recording and it's just staggering what you can pull out of a shot that is so unbelievably over exposed it looks almost totally white. As the recording is linear there is no highlight compression. As it's 16bit one stop has over 4000 grey levels, so even if it is so overexposed that the entire scene is in the top one stop, you still have 4 times as much brightness information in that one stop than 10 bit S-Log has in it's entire range.

Re: S-Log w/ 1.31 Firmware PDF
 

Thanks,
So if I'm understanding you right there is no inherent technical reason you couldn't manipulate or paint the SLog DR in camera even to an 8bit recording, but our you're suggesting 2 reasons against it.

1- Its just hard to do in camera as even when it becomes another gamma in the new firmware you just don't have that many parameters available to control in the F3.
I assume though that a good 3D LUT made with sophisticated software would theoretically be able to do that. Of course the F3 doesn't accept 3D LUT's so you'd need to record to something else.

2. But the 2nd objection is that even if you could record a sophisticated LUT then the curve would have so much compression in very specific parts of the curve that you would really be stuck with it and have very little ability to change it in post. I'm guessing less ability than you currently have with 709 or cinegamma?

Makes sense to me. Thanks

Re: S-Log w/ 1.31 Firmware PDF
 

Thanks once again Alister,

So if I'm understanding you right there is no inherent technical reason you couldn't manipulate or paint the SLog DR in camera even to an 8bit recording, but you're suggesting 2 reasons against it.

1- Its just hard to do in camera as even when it becomes another gamma in the new firmware you just don't have that many parameters available to control in the F3.
I assume though that a good 3D LUT made with sophisticated software might theoretically be able to do that though. Of course the F3 doesn't accept 3D LUT's so you'd need to record to something else.

2. But the 2nd objection is that even if you could record a sophisticated LUT then the curve would have so much compression in very specific parts of the curve that you would really be stuck with it and have very little ability to change it in post. I'm guessing less ability than you currently have with 709 or cinegamma?

Makes sense to me, although I am also very interested to see what Doug comes up with. Maybe you can get something that's halfway there, similar to the Canon log curve.

Re: S-Log w/ 1.31 Firmware PDF
 

Here's some excerpts from a two-camera interview that we shot yesterday using the new 1.4 firmware. Sorry, couldn't work a window into the shot. :-(

Re: S-Log w/ 1.31 Firmware PDF
 

Very nice Doug, not just the gamma but all your work on it. very lovely. You didn't by any chance shoot any of it with other gammas just as a point of comparison.

Re: S-Log w/ 1.31 Firmware PDF
 

Leonard, thanks for the compliment. Unfortunately there was no time on this shoot to test any other settings, and I think I'm pretty much through doing more testing anyway. I feel like I've found the right paint settings, exposure and white balance techniques, and a workflow that works for me. Time to stop fooling around trying to make tiny incremental improvements that will never even be noticed and get back to real work.

Re: S-Log w/ 1.31 Firmware PDF
 

Nice looking stuff, Doug.

Re: S-Log w/ 1.31 Firmware PDF
 

I know i'm not alone in being curious what the final settings were.

Re: S-Log w/ 1.31 Firmware PDF
 

Very nice Doug, as it should be, especially when you have very controlled lighting. With controlled lighting you shouldn't need log at all. Just light to suit the camera.

Re: S-Log w/ 1.31 Firmware PDF
 

Very interesting clip Doug to see what results an S-log PP profile will give you out of the camera.

I recently attended a Sony S Log workshop here in the UK and came away with the knowledge that you have to shoot S-log with a grey card @38% (ish) exposure, and then grade in post to get the look you want. Obviously your clip totally contradicts that assumption.

I just love knowledge and a work flow that goes against other doctrines. You obviously spend considerably time developing a PP and the quality of your work out of the camera in my opinion is second to none.

As with Leonard, will you be willing to share your PP settings? Or maybe include them in a new F3 DVD?

Great work and great threads!

Andy

ministry of video - video design, production and editing company based in london

Re: S-Log w/ 1.31 Firmware PDF
 

I don't think that was shot with a log profile, unless it was graded, but that's not how Doug works. He likes to create the look in camera and I don't think you can get that look with the S-log gamma curve modified in a PP. Perhaps Doug will enlighten us. If I had to place a bet I'd say REC-709 with some negative black gamma and a tweaked knee.

Re: S-Log w/ 1.31 Firmware PDF
 

Doug, was that magenta the exact color of his coat or is that an IR representation of a darker coat?

Just curious because I have seen IR magenta issues with the F3 S/Log & REC709 on similar clothing that was black or dark blue - especially with Diva 32K lights. The same Tiffen IR filter that the EX1/3 uses can work well to prevent it, but I often don't use it because in many situations it makes accurate white balance difficult.

Re: S-Log w/ 1.31 Firmware PDF
 

Bruce, the color of his jacket is accurate.

Re: S-Log w/ 1.31 Firmware PDF
 

Alister is correct. This interview was not shot with an S-LOG profile.
We basically just used the regular Picture Profile I recommend in my F3 training DVD with just a couple of modifications. No matter how much testing I do, I keep coming back to the original Picture Profile I created almost a year and a half ago and can't find anything that I like better than that. It looks great on-set for the client to view, it doesn't require any grading at all, and since there's no grading then there's no reason to hassle with a 10-bit external recorder.

Of course, this was not a shoot that would have benefited from the extra dynamic range of S-LOG anyway.

MASTERING THE SONY PMW-F3 CAMCORDER

Re: S-Log w/ 1.31 Firmware PDF
 

For shooting "direct to air" or basically anything that is not going to be graded the S-Log gamma curve is not going to work well unless you like a very flat un-interesting image. No amount of black gamma adjustment in a Picture Profile will ever really make log suitable for an ungraded production.

Most people like to see nice high contrast images (don't confuse high contrast with high dynamic range) with deep blacks and richly coloured mid and high ranges. The best way to achieve this in camera is to match the cameras gamma and dynamic range to the TV or monitors gamma and dynamic range. However this would result in a rather limited 5 to 6 stop dynamic range as this is all most TV's and Rec-709 are designed for. If you take a high captured dynamic range and simply display it on a lower dynamic range system you will end up with reduced contrast. The trick therefore is to keep your low and mid range as close to the gamma of your display as possible, as this is where we notice contrast the most and then carefully compress just the highlights using the knee or a cinegamma to gain dynamic range without affecting the mid range. The knee with standard gammas does this, but the knee can look quite ugly do to it's either on or off nature and quite severe compression. Cinegammas are not as abrupt, but the compression starts lower down the gamma curve so there can be some reduction of contrast in the mid range. To some extent this can be overcome by using some negative black gamma as this deepens the dark areas which increases apparent contrast.

The S-Log curve though starts it's compression at a very low point and as a result there is a big loss of contrast in the mid and low range. If you use a lot of negative black gamma to try to boost the contrast you start to get a stretched area between the dark parts of the image and the brighter parts and this does not look good.

Clearly Doug's Vortex-Q profile is well considered and does a very good job at producing a pleasing direct to air image. As I suspected it is based on conventional gamma as opposed to S-Log, it's a good example of just how good conventional gammas can be, especially when you have controlled lighting.

Re: S-Log w/ 1.31 Firmware PDF
 

Alister, thank you for the comments about my profile, but I must disagree that it isn't possible to use the new S-LOG gamma and get an image that would be good enough for "straight to air". That is possible.

Correct me if I am wrong, but I don't think you have tried the new firmware, right? If not, then you are at a disadvantage because when you get it you'll see that it is possible to get a pretty a good final mage with S-LOG gamma if you dial in the other paint settings to help it out.

However, with that said, I have still not been able to use the S-LOG gamma option to create a better picture than I can with the Cine gamma options. In other words, I can make S-LOG to look pretty good without grading, but never as good as Cine gammas. Even in shots that can benefit from extra DR.