D-Log vs D-Cinelike Video Noise

[LeafPeeper]

So I've recently started taking the time to learn about D-Log, color correction, grading, etc. I thought I had found that I liked D-Log the best with a custom LUT and some minor additional tweaks from me. However this weekend I did some shooting in D-Cinelike to compare. From a color perspective, either could work just fine for me, but what I've found is that D-Log seems to have significantly more noise (sharpness at +1 or even 0) than D-Cinelike. Has anyone else experienced this? I would normally suspect ISO settings, subject brightness, etc. to be the culprit, but I'm shooting in daylight in bright sunlight. I should have very little ISO noise - and in fact I don't in D-Cinelike. Is this expected with D-Log? Is the in-cam noise reduction algorithm different for different video modes?

FWIW, this is an older (March 2017) Mavic Pro refurb that I got from DJI Refresh. Other than the fact that it won't do 1080p/60 in a usable fashion and now this, I've been completely happy with it. It's running the latest firmware, and I'm using the latest version of DJI Go. I've been shooting in auto to start, but plan to experiment with manual settings to see if it's jacking up my ISO settings for some reason.

LP

 

[SkySquinter]

I never use auto mode, firstly get some ND filters then in manual mode set ISO to 100 and shutter speed to twice the frame rate. This will give you much better footage.

 

[Lake_Flyer]

So I've recently started taking the time to learn about D-Log, color correction, grading, etc. I thought I had found that I liked D-Log the best with a custom LUT and some minor additional tweaks from me. However this weekend I did some shooting in D-Cinelike to compare. From a color perspective, either could work just fine for me, but what I've found is that D-Log seems to have significantly more noise (sharpness at +1 or even 0) than D-Cinelike. Has anyone else experienced this? I would normally suspect ISO settings, subject brightness, etc. to be the culprit, but I'm shooting in daylight in bright sunlight. I should have very little ISO noise - and in fact I don't in D-Cinelike. Is this expected with D-Log? Is the in-cam noise reduction algorithm different for different video modes?

FWIW, this is an older (March 2017) Mavic Pro refurb that I got from DJI Refresh. Other than the fact that it won't do 1080p/60 in a usable fashion and now this, I've been completely happy with it. It's running the latest firmware, and I'm using the latest version of DJI Go. I've been shooting in auto to start, but plan to experiment with manual settings to see if it's jacking up my ISO settings for some reason.

I

LP

Since recently I noticed quite some noise in D-Log too, even on bright sunny days. But it used to be much less. It could be that a recent firmware upgrade changed something. I'm on the second last firmware. I never used any other mode actually.
Going to try D-Cinelike after reading your post.

{edit}
I always shoot in manual, using appropriate ND filters to lower the shutter speed if needed. But even on 100 ISO I see noise in D-Log.

 

[Davy Tung]

I’vs just seen on youtube that a guy recommend to use D-cinelike. I’m going to give it a try tomorrow

 

[LeafPeeper]

Since recently I noticed quite some noise in D-Log too, even on bright sunny days. But it used to be much less. It could be that a recent firmware upgrade changed something. I'm on the second last firmware. I never used any other mode actually.
Going to try D-Cinelike after reading your post.

{edit}
I always shoot in manual, using appropriate ND filters to lower the shutter speed if needed. But even on 100 ISO I see noise in D-Log.

Exactly - for the record, I'm already using ND filters, but if it was ISO noise caused by the cam selecting a higher ISO in auto, you'd expect ND filters to make it worse, not better. On bright sunny days, there's no reason the cam shouldn't be selecting an ISO of 100. That said, I do really wish these videos stored EXIF-like info so I could go back and check. I've now tried this on two separate days with the same results - ie: put the MP in the air and point it at a scene and let it sit. Then record some in D'Log, then switch to D-Cinelike and record again. Same style settings, same lighting conditions, same subject. D-Log has more noise.

I've now found some settings with D-Cinelike that I'm happy with, so that's my solution for now. I'm open to any other suggestions or thoughts.

LP

 

[Paul2660]

Double check and see if the D-log setting on the Mavic did up your ISO. On the P4 Pro, you are forced to ISO 500, and can't go to 100, which IMO is way to noisy. Last time I checked D-log setting on the MPP, you could shoot in ISO 100 in D-log, but with a newer firmware DJI may have changed that. I am not running current for a reason, still on March/April versions as they work for me.

Paul C

 

[Jack Daw]

On bright sunny days, there's no reason the cam shouldn't be selecting an ISO of 100. That said, I do really wish these videos stored EXIF-like info so I could go back and check.
LP

The video may not, but the stills do, so if you don't mind interrupting the video, you can switch over to stills very quickly and snap one off.

 

[LeafPeeper]

Double check and see if the D-log setting on the Mavic did up your ISO. On the P4 Pro, you are forced to ISO 500, and can't go to 100, which IMO is way to noisy. Last time I checked D-log setting on the MPP, you could shoot in ISO 100 in D-log, but with a newer firmware DJI may have changed that. I am not running current for a reason, still on March/April versions as they work for me.

Paul C

Now THAT could explain it. What could possibly be the logic for hardcoding something like that? If that's the case, I don't know why anyone would bother with D-Log. I will check on my next outing. Thanks!
LP

 

[LeafPeeper]

The video may not, but the stills do, so if you don't mind interrupting the video, you can switch over to stills very quickly and snap one off.

Excellent point! I could snap off a pic before changing each setting and the numbering will be maintained. Cool.
Thanks!
LP

 

[nevernamed]

I'm using d-cinelog and I really like it. I'm not one for too much post touch up and the raw footage from d-cinelog looks pretty good to my eyes..

I though I've seen something about noise in d-log video somewhere, and I was under the impression thats semi normal and a lot of that is cleaned up in post. how bad is it?

 

[LeafPeeper]

I'm using d-cinelog and I really like it. I'm not one for too much post touch up and the raw footage from d-cinelog looks pretty good to my eyes..

I though I've seen something about noise in d-log video somewhere, and I was under the impression thats semi normal and a lot of that is cleaned up in post. how bad is it?

It's worse than I can repair with the post software I have (Cyberlink Powerdirector 16) without completely wiping out most of the detail - and I don't want to pay more for something else right now, especially when it's clearly the Mavic's problem. I'm just going to switch to D-Cinelike.

LP

 

[nevernamed]

It's worse than I can repair with the post software I have (Cyberlink Powerdirector 16) without completely wiping out most of the detail - and I don't want to pay more for something else right now, especially when it's clearly the Mavic's problem. I'm just going to switch to D-Cinelike.

LP

i think you're going to enjoy the results

 

[LeafPeeper]

Well the ISO500 discussion gave me some ideas on better Google search terms and I found some good info. It sounds like the noise is expected - but you have to dial back the style settings, then bump the exposure significantly ("expose to the right").

How to shoot Log video using DJI's D-Log color profile (DPReview article)

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I think I may just switch to D-Cinelike since I like the output.

LP

 

[LeafPeeper]

Did some more tests yesterday. I think I'm done with D-Log as I suspected. Strangely enough, the cam settings seem to indicate the ISO is set to 100 in both auto and manual. I played with a bunch of manual exposures using the histogram, and while exposing to the right does help with the noise, I just can't get the images the way I want them in post. Maybe it's PowerDirector, but reducing the brightness/exposure in post just wipes out all highlight definition. If I reduce the exposure in the cam, I get more noise than I want. I also don't like the look of TrueColor or Vivid. I think it's back to D-Cinelike with a LUT and manual tweaking, or NONE and just doing what I want to it from scratch. Bummer. I was hoping D-Log would give me more dynamic range.

LP

 

[Kilrah]

Log needs to be exposed properly.
Its purpose is to allow storing more dynamic range into a standard 8-bit package, and does so by applying a curve that basically causes shadows to be shot at higher ISO than the highlights. So you may be set to use ISO100, but the fact you're shooting log means the shadows probably exhibits noise equivalent to ISO400 or 800.

The whole point is you'd then apply a correction (manual or LUT) that would restore a more normal curve and darken those shadows back again, reducing the effect.

Again Log allows packing more dynamc range, but it doesn't mean the camera actually has any more to pack. In the case of the Mavic it's there more for workflow homogeneity reasons, there isn't much to gain over cinelike as you've seen, the sensor just can't do better.

 

[Cliff_622]

All log gamma curves are noisy. Sony S-Log, Panasonic V-Log or C-Log.

Why? Because logarithmic gamma curves show you the ENTIRE output of the image sensor read out. That noise you see is literally the rock-bottom noise floor that sensor is seeing. Under rec709 or D-Cine curves, that noise floor is chopped out and left unused. The same goes for some unused highlights. So, log reveals DEEPER into the sensor's read out and REVEALS the "true" rock bottom output that a sensor has. Now,...it up to you on what to do with all that dynamic range. Do you clean it and use it in post or do you just crush the shadows and dump that dirty bottom end into the trash can.

Remember,....we are dealing with D-Log which is VERY flat and DJI only gives us 8bit color sampling, so contrasting that log back out will stretch the crap out those 8bits. The other problem is that D-Log tops its white out at 80 IRE and that really stinks. This is a HUGE problem for D-Log and color banding. Sony SLog-2 gives you max whites at the FULL 109 IRE which is very smart for 8bit log.

I wish DJI made a D-Log 2 that coppied Sony SLog-2

Also remember, we are dealing with a "small" 1inch-type sensor, not a larger Micro 4/3 or Super35 or full frame sensor. This little sensor is fantastic for its size but it's only got about 10 stops of "clean" dynamic range. So, appling a highly agressive gamma curve that only uses +15 to +80 on the scopes (instead of 0 to +109) its really kind of crazy.

I mean, Im not saying "dont do it" but it really is like trying as hard as you possibly can to squeeze 1 drop of water out of a rock.

 

[LeafPeeper]

Thanks Cliff and Kilrah -that was extremely informative. I had no idea. Funny that you mention the color banding, because that's my issue when I ETTR, then drop the exposure during post - I end up with too much color banding in the highlights (assuming I understood what you meant by color banding).

So given that the cam profiles seem to pretty much direct the amount and type of in-camera processing, what is the purpose of the 'None' color style? It would be pretty easy to assume that meant minimal in-camera processing, but I doubt that's what it means. Anyone know? ...because up until I started dinking with these stupid profiles, I was pretty happy with 'None' and a little post processing.

Thanks,
LP

 

[Kilrah]

"None" is basically "common consumer camera like", certainly not "no processing".

Also remember, we are dealing with a "small" 1inch-type sensor, not a larger Micro 4/3 or Super35 or full frame sensor.

1/2.3” even on the Mavic.

 

[Cliff_622]

"None" is basically "common consumer camera like", certainly not "no processing".


1/2.3” even on the Mavic.

Thats funny....I tbought I was reaching for my Phantom forum app! (Have both installed) LMAO! Actually, yes, both Mavics have a 1/2.3 and these sensors have much less dynamic range and a far worse signal to noise ratio. Honestly....ultra flat 8bit log recording has no place on a 1/2.3 sensor. The 1inch-type sensor is the rock bottom of the line for log recording on my opinion.

The Phantom 4 Pro uses an Ambarella H1 imave processor using 100mbp/s. The Mavic Pro uses an ANCIENT Ambarella A9 processor that dates all the way back to the GoPro Hero 3 at 60mbps. (The Air uses the same H1 as the P4P.) Sorry but its horrible for log gamma curve recordings.

 

[0Kajuna0]

I do really wish these videos stored EXIF-like info so I could go back and check.
LP

Just in case, if you had your "video captions" setting turned on, the ISO value will be recorded in the srt file by the same name as the video file.

I'm with Cliff_622. 8 bit, 60mbps, 1/2.3"... Just too much for D-Log. A more intuitive way to see it is the histogram. In D-Log only a small fraction gets filled with data. Then you'll have to stretch that data in post to get contrast back, thus exaggerating banding and probably noise. D-Cinelike with contrast set to -3 also provides "good" dynamic range and is not that aggressive with the data.

I even try to avoid slog2 and such on the a7sii. It's only really useful in extreme contrast situations.