s-log and new Sony x90

[Donald McPherson]

With the new X90 having s-log is it that much better than a camera set up with a good picture profile assuming that many are crap at colour grading?

[Doug Jensen]

There is no doubt in my mind that S-LOG combined with proper grading in Resolve is superior to anything that can be done with the normal REC709 gammas and typical paint menu settings.

[Cliff Totten]

Yup. No doubt.

SLOG-2 maps each sensor's full dynamic range from top to bottom. On that sensor, you are looking at close to 11stops-ish. Standard rec709-type profiles will chop that dynamic range and clip you for 6-7 stops output. (To maintain standard rec709 contrast levels, it throws out DR that the sensor sees)

So yeah, SLOG-2 custom maps all the photons those little pixel wells can hold, from empty to full, right up to 109 IRE.

Yes, you will get the maximum dynamic range that sensor can hold....but it wont be "free". To get that benefit, you will be forced to pay a possible 8bit banding penalty. (Its a scene dependant issue like blue sky)

Some shots "could" suffer gradient banding when you normalize it to rec709. Its not "garanteed" but it is certainly an elevated "possibily".

SLOG-3?....avoid it like the plague. Its way too flat for 8bit, maxes out at around 90 IRE and is brutal on 8bit. It doesn't even use the full amount of 8bit 0-255 values! SLOG-2 already maps the sensors full values to 8bit anyway so there is no need to use SLOG-3 with a further limited 8bit value mapping. SLOG-3 is not tailor mapped to each sensor model the way SLOG-2 is. SLOG-3 uses a fixed-set Cineon-type gamma curve. Its like a 16 stop curve? Whereas SLOG-2's curve is based on each sensor model's total and REAL output ability. It's not a good thing to dump an 10-11stop sensor into a huge 16 stop Cineon/SLOG-3 curve.....with only 8 bits of shade/gradient depth!

Remember, 10bit is where we'd all like to really use SLOG-2/3 as this has a color palette that somewhere near 40 times more than 8bit.

Use ProRes if you can. Even in 8bit, you will get more encoding deeper into the shadows and get less artifacts in grading than MPEG Long GOP. H.264 will sacrifice the bandwidth allocation to the shadows first when it is stressed. ProRes doesn't do this.

Hope this is not "TMI"...lol

CT

[Cliff Totten]

Duplicated post

[Craig Seeman]

On the z90, HD is 10 bit 4:2:2 so SLog-2 should be very nice there.

[Robert Young]

Looking at the specs- it looks like only SLOG-3 is available on the Z90
Or am I missing something

[Cliff Totten]

Just found that the AX700 has:

PICTURE PROFILE
Yes (Off/PP1-PP10) Parameters: Black level, Gamma (Standard, Still, Cine1-4, ITU709, ITU709(800%), S-Log2, S-Log3, HLG, HLG1-3), Black Gamma, Knee, Color Mode (Standard, Still, Cinema, Pro, ITU709 Matrix, B/W, S-Gamut, S-Gamut3.Cine, S-Gamut3), Saturation, Color Phase, Color Depth, Color Correction, WB Shift, Detail, Copy, Reset

So I'm certain that the X90 (woops!...Z90) will have the same SLOG-2 also.

Whew!,...you scared me there for a second as I have the NXCAM NX80 on pre order. (I just sold my X70. I dont need SDI as I shoot mostly 4k for everything now and dont need 10bit 1080p anymore...I still have a Z150 for that anyway)

CT

[Doug Jensen]

I have a demo Z90 in my hands and it definitely has S-LOG2 and S-LOG3.

BTW, Cliff, it is the Z90 not the X90. I keep making the same mistake! :-)

[Cliff Totten]

Haha,...good catch! ;-)

You gotta Z90? Spill your gutts,...what do you think?

Are you under NDA?

[Doug Jensen]

All I can say right now is that so far I like the Z90 very, very much. What a great picture! I think it looks better than the Z150 and almost as good as the FS5. I might be able to post some sample footage in a few days.

[Cliff Totten]

Doug, Im really ininterested in your opinion of that crazy-amazing PDAF. (Phase Detection Auto Focus)

I know you are not a fan of AF....I never was either. But this Sony technology is beginning to change my mind on the topic. Its sort of shocking really.

Really hope you run that feature through the ringer.

I love manual rings on true geared lenses with hard stops. Pulling focus on fly by wire, endlessly rotating and movement buffered lenses is a pain. So this PDAF "can" make shooting with that camera more tolerable for certain fast moving objects. Plus that object tracking technology? Damn...

But you tell me, you got one, I dont. Lol

[Doug Jensen]

Oh, I assure you I'll be taking a very close look at the AF capabilities of this camera. I have already braced myself for the potential blasphemy of embracing it. This could be the one to break the rules, but I have not turned it on yet. But with that said, I have already noticed the the peaking is much better than expected and the camera as a whole is much easier to operate that I would have expected for a small handycam. I am not a fan of that form factor at all, but this one is winning me over already.

[Paul Anderegg]

Doug, with the weird "spin the wheel 50 times" focus control of the X70, perhaps a "push to AF" would be a good custom button to add tot he Z90 :-P

Paul

[Cliff Totten]

So I'll share this rumor that has no evidence behind it:

About two-three years ago, I read that Sony and Canon cross-traded patents together. Sony wanted Canon's "dual pixel" AF patent (based on signal phase cancelation detection) and Canon needed Sony's EXMORs patents for their on-sensor column A/D conversion process.

"If" this happened, this allowed Sony to pursue signal phase cancelation processing without the fear of being sued by Canon. Not long after that, Sony began making HUGE strides in AF using the phase detection process. Coincidence? Maybe, maybe not!

Today, many in the industry are comparing Sony's PDAF to be on par with Canon's fantastic dual pixel AF. Is this because of the patent trade??? If so, we should begin to see Canon have a big jump in signal to noise ratio on their future sensors, which should lead to better dynamic range...something that has hurt Canon models in the past.

Anyhoo, this PDAF technology started on Sony Alphas models and I'm glad to see it trickling "up" the Sony price ladder into the pro models. Why does it seem that XDCAM has always gotten everything "behind" Alpha???

Sony's old contrast detection systems are done. From now on, we can expect every future Sony camcorder to have his PDAF. It's already incredibly wicked in the short time that Sony has been developing it. It's only going to get more and more incredible as time goes on.

CT

[Paul Anderegg]

Originally Posted by Doug Jensen

All I can say right now is that so far I like the Z90 very, very much. What a great picture! I think it looks better than the Z150 and almost as good as the FS5. I might be able to post some sample footage in a few days.

When you say you think it looks better than the Z150, do you mean with the HDR and log stuff, or just cleaner and sharper and such?

Paul