SL 601 video problem

[OKUSA]

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Hello everyone. I'm trying to figure out if this is common behavior with the SL when taking video. When I take video, the image on the screen & Atomos Ninja V is extremely dark with crushed black and very high contrast regardless of video settings. Making it hard to get proper exposure. When I press record, the image "opens" up and looks normal both on camera and with Ninja. The change isn't instant and the beginning of the videos record the behavior. Any suggestions or ideas? 

[Slender]

What is your monitoring set-up on the ninja ? Native, rec709? Are you shooting L-log from the camera? Is your atomos up to date?

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[OKUSA]

Not shooting in L-log, it introduces some bad noise artifacts. Atomos is up to date. In either native or Rec709 or even without the Atomos connected and just recording to card, the phenomenon is still present. 

[Slender]

On 2/10/2022 at 4:07 PM, OKUSA said:

Not shooting in L-log, it introduces some bad noise artifacts. Atomos is up to date. In either native or Rec709 or even without the Atomos connected and just recording to card, the phenomenon is still present. 

You should shoot in l-Log. Especially if you go with the added benefit of uncompressed HDMI ProRes.... With SL601 it will behave well at 400 and okay at 800. Sure, you will see noise until you apply your grade in post, but that is normal! Look at raw footgae at 640 iso from "king of darkness" Sony A7SIII it is riddled with noise. It's unavoidable, unless you cheat by smoothing it out in camera, which comes with other issues such as details loss, other artefacts... etc. All serious RAW work implies de-noising in post, most Log work in Low light will also command it unless you can overexpose your footage, but that differs camera to camera. Although it should be true with SL601 (less so with dual-gain SL2/s).

Make sure your Atomos is not set to a Lut ot r709 conversion. It should be input and monitor as "native". If you put a lut or a default r709 monitoring profile on top of your already r709 camera output, you are re-baking the cake and it will look impossible. Although recording on Atomos should remain un-affected.

[OKUSA]

I appreciate it. Log is much worse. I've seen other log and footage from the 601 and tend to think mine has some software issue. I upgraded to the newest firmware but to no avail. The noise doesn't seem normal, and it's not actually raw footage. But every video configuration creates same issues so I'll have to have it looked at. 

[Flore]

@OKUSA Same for me... It's very very grainy/noisy. I've got both SL typ601 and SL2 and I have the same feedback as yours for both cameras when filming in L-log, even when  at 2 stops underexposed (which by the way looks horrific on the Ninja V despite the visual aid LUT Leica Classic or Natural). 

I can't seem to degrain it in Resolve without altering it. I wonder what I'm doing wrong... 

[hansvons]

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4 hours ago, Flore said:

I wonder what I'm doing wrong... 

Noise is directly connected to exposure. Underexposure = noisy shadows, overexposure = blown highlights and video-esk appearance. The Sl2-S has its sweet spot at roughly 400-800 ISO, the SL2 probably one stop lower, 200-400 ISO and the SL perhaps somewhere between 100-320 ISO. When evaluating the exposure of flat log images, people tend to underexpose often by 1-2 two stops. That's when a Rec709 viewing LUT comes in handy (SL2 and SL2-S have that option).

I can assure you that the SL2 and SL2-S are capable of appealing film-like video footage of the most acceptable fidelity for a hybrid mirrorless camera. Please bear in mind that in L-Log, the SL2 and Sl2-S are Rec2020 HDR cameras, whereas, to my knowledge, the original SL's log footage lives in Rec709 colour space.

[Photoworks]

23 hours ago, Flore said:

@OKUSA Same for me... It's very very grainy/noisy. I've got both SL typ601 and SL2 and I have the same feedback as yours for both cameras when filming in L-log, even when  at 2 stops underexposed (which by the way looks horrific on the Ninja V despite the visual aid LUT Leica Classic or Natural). 

I can't seem to degrain it in Resolve without altering it. I wonder what I'm doing wrong... 

I would suggest you use the waveform monitor and shoot in L-Log. Most of the time I will shoot +1 stove over the meeter by looking at the waveform where it will clip..

I don't know if the 601 has a waveform, but an external monitor will do that too.

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[Flore]

@hansvons Thank you so much for this. I was doubting of my own abilities as a photographer after my first tests. I read somewhere a user who underexposed in log and I followed... which was the wrong thing to do. So I've done some tests: F-stop, after F-stop keeping ISO at 400 and shutter at 1/50 for 25fps. I'm yet to import them in Resolve. But they look faaar better than the initial tests. I also tested the "out of the camera" video styles: Vivid, Standard and Neutral, to see what appeals to me more. I also tested with a Leica x16 ND filter to open the iris to the max (Summilux SL 50mm). I noticed a shift in WB which will be easy to correct in post. Now I need a colour grading course! The head of cinematography of my film school has accepted to perform rigorous tests in studio with me and possibly fiddle with what I find my favourite Leica LUT to create one that works better for me.
I hope he'll be able to help me set up my Atomos Ninja V better. For now I can't display the waves on it (only on the Leica screen), can't display the LUTs I've imported properly and the zebra is different from the Leica, I need to adjust them to the same sensitivity. I'm buying a new generation variable ND filter which I'll test in studio. 
Next hurdle is a Leica SL + Smallrig cage compatible microphone... Another basket of crabs as we say in French. I might post a new post on that one.
Again thank you for your precious help!

[Archiver]

6 hours ago, Flore said:

@hansvons Thank you so much for this. I was doubting of my own abilities as a photographer after my first tests. I read somewhere a user who underexposed in log and I followed... which was the wrong thing to do. So I've done some tests: F-stop, after F-stop keeping ISO at 400 and shutter at 1/50 for 25fps. I'm yet to import them in Resolve. But they look faaar better than the initial tests.

Yes, do not underexpose log footage, that way lies peril and disaster. I haven't used the SL, but Panasonic v-log on the S5 doesn't respond too well to underexposure, and seems to perform best with slight overexposure. I usually try to expose v-log with a nice middle curve on the histogram while avoiding blowing highlights as indicated by the zebras in high contrast situations. This sometimes results in the camera's metering saying it is +1 or so overexposed.

[hansvons]

Hi Flore, Thanks for the kind feedback. Here are a few more insights to make your journey more enjoyable:

LUTs: Always use LUTs after the grading. That way, you retain your footage's DR. You will cripple the camera's DR badly when using the Rec709 LUT before you grade. When grading in the Rec2020 colour space, you will retain all DR and get the right colours because the SL2's colour space is identical to Rec2020. Consider the Sl2 as an HDR Rec2020 camera. 

Without proper colour management or a properly used LUT in Rec709, the colours will be off/funky (reddish skin tones, cyan blue sky). The Natural LUT is the original Leica LUT for Rec709 colour space. All else is an unnecessary watering-down attempt to please the customer with superfluous choices (Arri provides only one LUT because there's only one Arri colour developed with the best cinematographers involved and is THE industry-standard in-camera colour science).

No LUT: Yes, that works nicely in Resolve because the SL2 is an HDR Rec2020 camera. 

• Set in Project Settings Colour Science to DaVinci YRGB colour managed, 
• uncheck Automatic colour management. 
• Select in Colour processing mode HDR Rec2020 intermediate 
• and as Output colour space Rec 709 Gamma 2.4, assuming your programme monitor is an SDR Rec709 monitor. 

The colour you will get is accurate. The gamma is too flat but be easily corrected in the grading process. This way, you get the whole SL2 gamut. 

Here's the rub: Leica provides a Rec2020 LUT. This LUT will add a contrasting gamma curve for a better grading experience in the HDR Rec 2020 colour space (again at the end of the pipeline) that doesn't convert the colour space like the Natural Rec709 LUT (which converts HDR Rec2020 to SDR Rec709 PLUS adding the mentioned above gamma curve (Rec2020 and Rec709 share the gamma 2,4).

If that sounds like Greek to you, well, welcome to today's postproduction world when future-HDR meets dinosaur SDR.

Ninja: always feed the Ninja with the flat L-log. You can upload the Leica Natural rec709 LUT to the Ninja as a view LUT, which is the correct LUT because the Ninja's screen is a Rec709 screen. However, the Ninja ProRes footage will be exactly the same footage as the internally recorded Log clips in terms of colour space, which is, you guessed it, HDR Rec2020.

 

 

Edited April 2, 2022 by hansvons

[Flore]

@Photoworks That was enormously helpful. 
What's your personal rule? Not reaching the last dotted line I guess. Do you try to touch the second dotted line from the top (third line from top if you count the solid line)?
What rule should I have to make sure that my footage won't be too grainy or overexposed? Could I for example be "parked" at +1 to 2 stops and make sure I'm not touching that last dotted line, more or less resting on the one underneath? And keep ISOs parked at 400 and go to 1600 only of there is no other way...
I'm getting these LightPro Flexlite LED pannels. They might be a great help in case I'm stuck.
The SL typ 601 doesn't have a waveform I don't think. It'll make it much harder to go in Log if I need a camera B... It also seem to have a different colours space. I can't find official info about this yet. 

[Flore]

@Archiver Peril and Disaster ;))) That's exactly what's going on. I'm now getting much better results overexposed. I just need to find the sweet spot. I'm better at curves than histograms. But for the 601 I'll need to investigate what a " nice middle curve on the histogram" is
Now I wonder if I can trust the zebra clipping tool in log.

[Flore]

Hi @hansvons

It does sound a bit Greek at this stage but this is very helpful. I'm keeping your workflow in my notes and I'll pay for DVR today so I can try it out. 

OK, so I misunderstood the use of LUT in post. I thought you'd add the LUT and tweak it. 
So you're saying you colour grade first and put the LUT as the last node? I really would have thought that a LUT was there to avoid you doing all the work. Simply adjust each clip to homogenise the look you want. 

Regarding the Ninja, I've uploaded the REC709 and REC2020 just to try and it doesn't work. I must be doing something wrong. I need to watch more Ninja tutorials... I might try to erase those (uploaded a long time ago, they could be obsolete), and upload the ones I downloaded via the L-camera-forum. 

Thank you again for your help!

Flore

[Photoworks]

regarding the exposure: you say you have an atomos.. the waveform works the same way. you want the highlight to roll of the top if you see it going flat across on the top you are loosing data. 

Setting +1 does not work for everything .

You can do a transform in DaVinci Resolve or use a LUT.

There are many different LUTs. Come of them to convert the L0g Footage to Rec2020. those are ok to put in the front.

Any out that give effect of color just should be near the end of the nodes..

 

 

[Flore]

On 4/2/2022 at 11:53 AM, hansvons said:

• and as Output colour space Rec 709 Gamma 2.4, assuming your programme monitor is an SDR Rec709 monitor. 

@hansvons Do you mean by programme monitor the screen I'm working on? I'm trying to find what is the colour space of my iMac Pro 2017. I'm reading different things and it seems that it could be P3-DCI. Should I put this in the Output colour space?
Does it matter a lot?

[hansvons]

6 hours ago, Flore said:

Does it matter a lot?

Yes. 

I sense that you are a film student. If so, I strongly advise making yourself familiar with the concept of colour spaces, scene-referred vs display-referred etc... In today's cinematography, this knowledge is mandatory to understand what's going on under the hood and why specific results are better than others. In a way, the cinematographer's job is more challenging than back in the film days, when there were only scene-referred colour spaces (the stock we were using) and only two display-referred colour spaces, Television (Rec 601/NTSC) and the print film for cinematic projection.

[Flore]

Hi @hansvons,

I'm studying documentary directing. So I'm not taught at all any cinematography skills or grading techniques. That's why I came here to see if Leica users had some input on the best way to film in Log. I think it'd be a shame to lose all that DR. The head of cinematography who offered to help, now says he has no time. So you're right, I'm  going to google it and learn what I can before shooting in a few days. 

Your help was fantastic. Thank you!

[hansvons]

6 hours ago, Flore said:

I'm studying documentary directing. So I'm not taught at all any cinematography skills or grading techniques.  The head of cinematography who offered to help, now says he has no time.

@Flore That's what I experience on the teaching side in uni as well. Curricula are crippled, don't deal sufficiently with real-life work and staff tends to be overworked or lost interest somewhere on the road/professional life. If you need input/advice on concrete issues such as test shoots, you are always welcome to contact me at hans at vonsonntag.

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[Flore]

@hansvons Thank you so much for your offer. I've followed your advice and I'm currently watching lots of YouTube videos (couldn't find any digestible or even recent colour book in the film school's library). 

I'm re-reading your posts and it's starting to make sense. I've set up DVR the way you indicated. I've attempted to grade and it looks really good to my still untrained eye. 

I guess you cannot import Leica SL2 (or 601) settings there, like you can other brands of cameras. I see people simply select their camera and colour profile and BAM! It looks perfect. They only have to grade prior to that settings node.

One question: do you need to put the REC2020 to REC709 LUT in a node (the LUT without the contrast) after the REC2020 Natural LUT as the final node?