S-Log w/ 1.31 Firmware PDF

[Doug Jensen]

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. :-(

Sony PMW-F3 Picture Profile Test on Vimeo

[Leonard Levy]

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.

[Doug Jensen]

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.

[Chuck Fishbein]

Nice looking stuff, Doug.

[Leonard Levy]

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

[Alister Chapman]

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.

[Andreas Andreou]

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

[Alister Chapman]

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.

[Bruce Schultz]

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.

[Doug Jensen]

Bruce, the color of his jacket is accurate.

[Doug Jensen]

Originally Posted by Andreas Andreou

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

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

[Alister Chapman]

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.

[Doug Jensen]

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.