Need help with CinemaDNG wrong settings

[Fina]

Hello everyone,

I was out shooting in the evening. Had everything set up to shoot cinemaDNG. Was using the Laowa 9mm lens on an X7 camera on the I2. Shot the video and got home and looked at the footage. The footage on the SD card was correct, I was using a low iso and footage was dark (the way I wanted it). I shot in manual with a low iso and low aperture. The footage on the SSD was another story. It was bright and grainy. It was as though I had it set to auto. Maybe there is a setting I don't know about. Hope someone has some answers because I plan to shoot on Sunday evening. Thanks in advance.


Fina

PS- the "SSD Look" box was grayed out.

 

[niki]

Camera setting are the same for both recordings, the difference comes from the fact that on the SD you have QuickTime file with embedded rec709 look but on the SSD the cDNG footage is RAW and doesn’t have any looks embedded. Because of that it depends in what video editor you open the cDNG footage and what look settings this editor has for showing the raw files.

Some editors are pre set to apply automatic look conversion while others don’t. For example in Davinci Resolve you need to go to the raw settings and set the Color space you want for the footage. There you can choose to show it directly in to rec709 which theoretically will be close to what you see on the SD card. But because DJI have speciffic workflow you may need to adjust the exposure setting to something different than 0, usually I have to set this between 1 to 2 so the footage start look similar to the SD one.

 

[Fina]

Niki, this isn't the problem. The camera settings are NOT the same! The cDNG look as though they have an ISO of 1600, not the 100 that I dialed in (and the mov file has). They are very very grainy and bright. I have shot CinemaDNG before and the files on the SSD were the same exposure as the quicktime file. I even took the CinemaDNG files and put them inside of Light Room in the past. And it's not about having a look or LUT applied. In the past the cDNG files had the same settings as the mov file. Now the mov file had the correct settings but the cDNG files were wrong. It looked as though the cDNG files were set to auto instead of me having them dialed in. This is so frustrating. I don't know if the problem is the camera/gimbal, the SSD or maybe the processing unit. BTW, I can't even choose a look for the cDNG, it is greyed out on app.

 

[ZCDC]

The I2 can do very strange things when it comes to camera and recording settings. I think some firmware revisions were a little worse than others but it was basically universal. Everyone complained about it for years but nothing was ever done. You have to always watch your record and camera settings like a hawk. Especially after any kind of major changes in the menu, switching between stills/video or even just power cycling. Sometimes after even doing nothing. Adding the Laowa is another variable since the camera thinks there is no lens attached and that can also trigger strange behaviors like spontaneous changes to any and all camera/look/record settings. It's frustrating for sure and just a part of life with the I2. It burned us a few times in the earlier years but then we were vigilant. I'm not saying this is the exact cause of what you experienced but it could be. I would try switching out of CDNG, installing a regular DL lens, record some files in prores, then switch back to CDNG and test some of those files as a baseline. Then if that's working as normal, then switch back to the Laowa and test it again while keeping a close eye on settings.

 

[niki]

The cDNG look as though they have an ISO of 1600, not the 100 that I dialed in

Have you checked the cDNG in lightroom? There you can see what ISO was used.

I suppose you know and understand that there are no separate camera/exposure settings for the SD and SSD.

Do you have the same problem with other lenses?

Long time ago I’ve had a shoot with Laowa 7.5mm and X5R camera for which I had to do hot swapping so to enable RAW recording on the SSD. While it was always working, for one of the flights we got very distorted and low quality footage. After a lot of tests I managed to reproduce the problem and it turned out to be the way I hot swap the lens, it wasn’t registered correctly by the camera. So if this happens only with the 9mm lens it’s something caused by the lens itself.

 

[Fina]

Hello, thank you for your replies. I finally had free time to do a serious investigation, and the problem was I wasn't hot swapping the Laowa lens correctly. I rarely shoot cdng except for evening. Now I know what to do and everything is working correctly.

 

[samlevy0515]

Looks like the SSD recording may have been accidentally set to "Auto ISO/Exposure" mode, or a "D-Log color mode" with preview enhancement enabled, causing it to look different from the raw SD card footage. Before your next shoot, double-check that the color mode and exposure settings under "Recording Settings" match your SD card setup exactly.
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