My lame desqueezing workflow. Am I doing anything wrong?

[Wannabe]

Here is my workflow. You guys tell me if I am doing anything wrong (most probably I am).

1. I use a Canon EOS-M camera with Magic Lantern Crop Mood installed and shoot a clip in 4.8K, 2.35:1 anamorphic.

2. I then use the MLV app to export the .MLV file to AppleProRes LT for the sole purpose of finding out what the final de-squeezed size should be. It turns out that the final size must be 4800x2040 pixels. I write this down.

3. I then use the MLV app again to export the same .MLV clip to CinemaDNG Lossless.

4. I create a new project in DaVinci Resolve.

5. I change the project settings (File > Project setings) to Custom and then enter 4800x2040 pixels

6. Then I import the CinemaDNG sequence in the Media Pool of DaVinci Resolve

7. In the Cut page I drag the CinemaDNG sequence down to the editor tab, and this automatically creates a new Timeline

8. I right click on the new Timeline and do Timeline Settings > uncheck Use Project Settings > Mismateched Resolution = Stretch frame to all corners

Tada! I now have a perfectly de-squeezed footage.


Now. I see one huge problem with this workflow.
The original CinemaDNG's are 1020 pixels tall, which means that when I stretch them to the final height of 2040 pixels, I lose quality.
If I leave them at 1020 pixels of height, then I no longer have 4.8K footage. It is a Catch 22 situation.
What should I change in this workflow?
How do you guys manage to upscale the 1020 pixel DNGs to a larger size without loss of quality?



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[Walter Schulz]

2. Is unneccessary because Bilal listed all modes and their resolutions. You are re-inventing the wheel.

[Walter Schulz]

The original CinemaDNG's are 1020 pixels tall

?
In 4.8k 2:35 your resolution is 1600x2040 which must be expanded to 4800x2040.
I have troubles to understand where your 1020 pixel setting happens.

[Wannabe]

2. Is unneccessary because Bilal listed all modes and their resolutions. You are re-inventing the wheel.

Sure, but I wanted to get the de-squeezed numbers. Once I had them written down on file, I no longer go through this step.

[Wannabe]

?
In 4.8k 2:35 your resolution is 1600x2040 which must be expanded to 4800x2040.
I have troubles to understand where your 1020 pixel setting happens.

That's the big question.
My DNG's are 1020 pixels tall.
Maybe I have set wrong export settings in my MLV app.

[Walter Schulz]

Sure, but I wanted to get the de-squeezed numbers. Once I had them written down on file, I no longer go through this step.

What is easier?
a) Looking into Bilal's chart. First number x 3 = desqueezed number.
b) Your workflow?

Don't get your drift.

Maybe I have set wrong export settings in my MLV app.

Maybe it would be a good idea to show/examine them? Just a suggestion ...

[Wannabe]

It turned out that my image viewer (IrfanView) was reading the resolution of the CinemaDNG's incorrectly.
It erroneously reported them as being 1020 pixels in height.

I opened the DNG's in PhotoShop and they were 2040 pixels in height. So it's all starting to get clear now.

[Wannabe]

To all the IrfanView users out there: make absolutely sure that you disable this function in Settings > Plugins. Otherwise IrfanView will report half the real size of your DNG's.








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[Kharak]

I would rather do the stretching in the Color Tab. In the Sizing - Input Sizing, under Height, set your desired stretch factor fx. 1.664 for ML line-skipped 60p.

This way, you can mix different source material with different aspect ratios, so you don't stretch 2:35.1 footage to 16:9.

But if the entire project has source footage from same camera and aspect ratio, then set project settings to your desired resolution and stretch to corners.

I also think you should set your project to a standard resolution, like 5k or 6k, because I think you might risk degrading the quality of your uploaded videos, as the host will most likely resize 4800x2040 either down or up to a standard, which can have adverse effects on quality, but ymmw.

[Wannabe]

I also think you should set your project to a standard resolution, like 5k or 6k, because I think you might risk degrading the quality of your uploaded videos, as the host will most likely resize 4800x2040 either down or up to a standard, which can have adverse effects on quality, but ymmw.

Great advice, thank you!