S-Log question

D10S

D10S

Well-known member
Maybe this is a stupid question, but right now seems feasible to me, but to simple to work.

I understand that it will take lots of practice and work to get used to the image that you will see from your camera when shooting S-Log without LUT. My question would be, can't you set up your camera for a shot with S-Log off, get it to where you want and then turn on the S-Log? I'm gonna be shooting S-Log at 4:2:2 recording to a PIX240, so I won't (as far as I can see) be able to take advantage of the LUT.
 
And then I can set my camera using the 709 settings as my reference and the S-Log will be recorded to the external recorder? So then do I send the S-Log signal from the right HD-SDI to the external recorder and use the regular SDI out to go to the monitor?
 
The design of the camera is for you to use a 4:4:4 recorder over dual link (or 3G) to record the SLog signal, and to monitor (with LUT) over the "regular" SDI port. The LUT on the monitor port can be turned off though.

The problem though, is that for those of use with 4:2:2 recorders, simply attaching to one side of the dual link output doesn't work... doesn't provide a working clean signal. This means you're forced to record out of the "regular" SDI port... which, in turn means you can't apply the LUT during recording.

My Slog upgrade is on order, so I'll be able to address this question better in a week, but...

1. There's no need to switch 709... you can just flip the switch to turn the LUT on, then turn it off before recording.

2. An alternate workflow would be to use a box like the Blackmagic HDLink ($500) to add the LUT. In the case of the HDLink, it accepts a dual link input, and outputs over single link SDI and DVI (for cheap on set monitoring)... so you can feed the monitor out of the camera to the recorder, and the dual link feed to the HDLink, and in turn to the monitor. In fact, since the HDLink lets you decide whether or not to apply the LUT to the SDI, you could have two monitors... a DVI monitor, LUT applied, and a SDI monitor, clean SLog feed.
 
So I would just record using the regular SDI out? I can loop that through to a monitor I assume, correct? What would happen if you left the LUT on when recording in 4:2:2?
 
No, you can only use the SDI for both. You only change the setting to do either Slog or 709

EDIT: Sorry I took to long to post.
 
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So to get this straight. When shooting S-log at 4:2:2 I can send the signal via the single SDI to both a monitor and an external recording device by looping the signal. Then I can turn off the S-log output to set-up and view the image if I want, and then turn back on the S-log when I go to record?

What am I missing, if anything?
 
The sLog image is not so weird. You can shoot off that. Its not like panaLOG, or ARRI C LOG, where the image is practically unviewable its so flat. Sony sLog is pretty close to normal looking. This is why you use waveform monitors. Set skintones to 35-40 IRE, and using a spotmeter, or the cameras marker function set you highlights to where you want them.

Its much more like exposng for film.

What happens s this, the camera lifts the blacks to about 15IRE, and the top goes up to 110. In post you bring the blacks down to 0, and then boost the mids(skin) up to appropriate levels to your taste. Then you place the highlights to where you want. its not so hard to use. Don't be afraid. If you can shoot and monitor cinegamma, u can shoot slog. To approximate what its like, shoot with cine 1, then manally set the black level up to 15ire. That's what slog looks like, just with better highlight retention.
 
Timur is right, it's entirely possible to just work with the Slog image. An onset LUT is primarily a boon for handling the client/producers who are going to have a hard time grasping that everything is okay unless they have a "What you see is what you get" monitor. That's personally the only reason I'm adding the HDLink to my arsenal... it's for the client.
 
However, can you not switch the S-Log OFF to set up the shot and to make the client happy, then turn on the S-Log when you record your video? I would assume that if this works you'd set up your shot with a very basic setting on the camera before switching back to S-Log.
 
With the caveat that I haven't worked with Slog yet (big caveat) and I've nevertheless been complaining about it's implimentation here for weeks- D10S's idea sounds attractive though a bit of a pain. The big advantages to me sound like you can get a WYSIWYG monitor out for lightng and client approval that will adapt to color balances other than 3200 or 5600 and you don't need a DVI monitor. This could be useful to both client and the DP in some circumstances. Recording a few moments of each shoot to the camera cards could provide a color reference to the colorist.

Is HDLink the only way to provide a LUT to a monitor now in 4:2:2? That means you now need to have a DVI input monitor. Will HDLink run off battery power? Doesn't look especially portable.
 
I don't think it's the only way. And it does have an SDI output, as well as the DVI. And the DVI can output to an HDMI monitor. I think of the HDLink as a video village solution, not a run and gun solution. And for me it's portable enough - it'll fit in my monitor case.
 
If u can afford a F3, Kipro, and log, u can afford a monitor that accepts LUT's.

Use it, its really as simple as that. The HDlink box that does LUT's is another option as its so small, you can velcro it to the back of the client monitor, and have that handle all the "look". Its $500. You're shooting LOG for 16000.... it will pay for itself in 1/2 a camera rental, and you can use it for any monitor. Just load a standard 709 LUT, or something that delogs the image that's just basic and call it a day.
 
I was just looking for ways to utilize what I already have. I've got a $3000 Panasonic field monitor and a $1500 Marshall field monitor plus the monitor that will be on the PIX240.
 
TimurCivan said:
If u can afford a F3, Kipro, and log, u can afford a monitor that accepts LUT's.
Click to expand...

Likely true, but for those who already own a monitor, upgrading to a monitor with LUTs is a hefty expense, particularly for a large panel. A quick search of B&H indicates I would need to pay $5000+ for a 24" production monitor with LUTs. If I hadn't already dropped 3.5k into my LMD-2450W, that would be acceptable, but... hence my consideration of something like the HD Link.
 
Can someone with S-log tell me if this is true? S-Log doesn't look 'that' different. It sounds like if I set my exposure in cine4 at WB 5600, switch to S-log and then dial down one f stop it should be in the right ball park. (I'm saving for s-log, a monitor is out of the question.)
 
I dont quite understand your question.

Youre trying to replicate sLog?

Shoot Cine1. its the one with the most Dynamic range, and the least "smushing" of image information. record 10bit, and under expose by a stop ( the F3 holds 6stops under key, and 5 over, so basically lower your at key "midpoint" to split the difference, and make it 6 and 6.) and boost it back in post. Add a little extra fill light to keep the blacks from getting muddy.
 
TimurCivan said:
I dont quite understand your question.

Youre trying to replicate sLog?

Shoot Cine1. its the one with the most Dynamic range, and the least "smushing" of image information. record 10bit, and under expose by a stop ( the F3 holds 6stops under key, and 5 over, so basically lower your at key "midpoint" to split the difference, and make it 6 and 6.) and boost it back in post. Add a little extra fill light to keep the blacks from getting muddy.
Click to expand...

Sorry I was less than clear. What I was getting at was how expose s-log without a lut monitor.
 
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