RAW 120 FPS

Started by Kanakori, June 13, 2018, 11:34:26 PM

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Kanakori

Hi guys, I'm going to shoot a music video with ML in about 2 weeks. With B roll I prefer 120fps over 60fps so I'm thinking of using twixtor. Does anyone have any experience with this or knows what settings I should use in-camera and in post? My biggest question is with the sutter speed, I guess I should double it if I want to convert 60fps to 120? I appreciate any help and tip. Thanks

50mm1200s

The shutter speed should be minimum of 2x the final fps you want. So, for example, if you want it to be 120fps, you'll need at least 1/240 shutter speed. I suggest you use the lens wide open (<f/2.0) or else you will have to up the ISO and Twixtor don't do well with noise.
If you're recording in sunlight, try to use Exposure Override in ML and set it to 1/8000.
Also, if you don't need audio, turn on the FPS override and choose "High FPS" preset.
On Twixtor, I use these settings (on AE - always work for me):
- Image Prep : Contrast/Edge Enhance
- Frame Interp : Motion Weighted Blend
- Warping : Foward

Kanakori

Quote from: 50mm1200s on June 14, 2018, 01:16:42 AM
The shutter speed should be minimum of 2x the final fps you want. So, for example, if you want it to be 120fps, you'll need at least 1/240 shutter speed. I suggest you use the lens wide open (<f/2.0) or else you will have to up the ISO and Twixtor don't do well with noise.
If you're recording in sunlight, try to use Exposure Override in ML and set it to 1/8000.
Also, if you don't need audio, turn on the FPS override and choose "High FPS" preset.
On Twixtor, I use these settings (on AE - always work for me):
- Image Prep : Contrast/Edge Enhance
- Frame Interp : Motion Weighted Blend
- Warping : Foward

This is exactly what I needed to know! Do you happen to have any demonstration? Anyway, thank you very much for the help.

Kanakori

In exposure override I don't have the option to increase the numbers I can only turn it on and off. Then on fps override do I set it to 23.976 or 60? Last question, is 1600 ISO too high for twixtor?

50mm1200s

Quote from: Kanakori on June 14, 2018, 02:41:51 AM
In exposure override I don't have the option to increase the numbers I can only turn it on and off.

Yes, Exposure Override let you choose some shutter values you wouldn't have with default canon firmware. Just turn it on and then change the shutter speed. You can also use the "fine tunning" settings on the movie tab, for fine control over the shutter speed.

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Then on fps override do I set it to 23.976 or 60?

Set to the maximum (probably 60 FPS), with the "High FPS" option (press the [Q] button).

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Last question, is 1600 ISO too high for twixtor?

It depends on your camera. High-end cameras like MKIII will have no problem, even at 3200. On low-end cameras such as "Rebel" series (600D, 700D, etc) try not to go higher than 800 ISO and never higher than 1600, since on these cameras they apply digital gain, not analog (generates much more noise).
If you really need more exposure and your lens is already wide open, you can apply a denoising algorithm (like NeatVideo) and then use Twixtor.

I don't have any good demonstration, I generally record people talking, so there's nothing too dramatic like water splash's and so on. But, I assure you that the results are pretty good if you have enough light and a fast lens.

If you're using normal recording (not MLV) and have a fast card, use CBR 3.0x for higher bitrate. Also, use some flat picture style, for better dynamic range (see LogNeutral). On the AE export settings, use a lossless codec, such as Lagarith or Cineform, so you can do the color grading without losing even more information.

Kanakori

That's pretty high ISO, I had no idea. I own a 5d M3 and several CF cards (Sandisk extreme 120mbs and 160mbs). Should I use the CBR 3.0 for everything in general? Also, I recently downloaded the James Miller Log profiles and I still havent decided if I should go for the Log2 version or Log3 version. Thanks again for all the help.

50mm1200s

Quote from: Kanakori on June 14, 2018, 04:09:45 AM
I own a 5d M3 and several CF cards (Sandisk extreme 120mbs and 160mbs) should I use the CBR 3.0 for everything in general?

Yes, always. If you have these cards and MKIII, I highly suggest you use MLV rec instead of normal h.264. You probably know, but some people can record 48 FPS using 10-bit MLV. I can't recommend this enough for you, since the result will be dramatically better.
A simple workflow would be:
- Check if MLV_rec module is loaded
- Set to 1920x1080, 10-bit
- Record using ETTR and/or Dual-ISO
- Input the MLV files into MLVApp
- Check if the exposure and WB is correct. Choose "AlexaLog" in "Tonemapping" and export to Prores 444.
- If the output has noise, use NeatVideo or other denoiser
- Use Twixtor on AE and export to Lagarith or Cineform
- Color Grade as you wish (Logarist and Premiere Lumetri work well for me). For sharpen, I use Samurai (from Digital Anarchy).

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Also, I recently downloaded the James Miller Log profiles and I still havent decided if I should go for the Log2 version or Log3 version.  Thanks again for all the help.

If you record using Raw (MLV), the picture style will not affect the footage, only if h.264. I haven't used these from James Miller, but some years ago I tested every single one of them. The VisionTech 2.0 (from Vision-Color.com) have good results and LogNeutral (linked above) is also very good. Today I only use LogNeutral in all my works.

Kanakori

That's a different setup from what i usually have. I record in raw lossless 12bit most of the time on the raw video module (not the Mlv) because of space and things i've read, making it sound like a good mid-term.
48fps giving better results than the 60fps option? I use crop rec for the slow motion.
I also can't find the option to go up to CBR 3.0.
You're kinda disputing alot of what I've been doing :-X Granted I'm still new to this

Walter Schulz

CBR/VBR settings are for H.264 recording only.

Kharak

I have not used twixtor a lot. But from my understanding, the rule of thumb for twixtor to work at its best is to not record any motion blur in camera. So as Low a shutter angle as possible. For 60p, go >1/500 if possible, so that twixtor sees each frame crystal clear and can then better interpolate the new frames. Also if recording h264, make sure its All-I not IPB compression.
once you go raw you never go back

50mm1200s

Quote from: Kanakori on June 14, 2018, 08:11:32 AM
That's a different setup from what i usually have. I record in raw lossless 12bit most of the time on the raw video module (not the Mlv) because of space and things i've read, making it sound like a good mid-term.
48fps giving better results than the 60fps option? I use crop rec for the slow motion.
I also can't find the option to go up to CBR 3.0.
You're kinda disputing alot of what I've been doing :-X Granted I'm still new to this

Well, forget what I said about CBR, I thought you was recording in normal (h.264), not raw.
CBR will only affect normal recording.
For slowmotion, 60fps will be better, but I don't think you can do 1080p at 60fps without frameskipping.
Also, you should be using MLV or mlv_lite instead of raw_rec.

Kanakori

By raw rec I meant mlv_lite! I'd still like to try out the h264 with high bitrate though, he quality might increase alot.
I remember being able to record continuously on 60fps with crop rec however at this moment It keeps hitting the red whenever I try it, only giving me about 15 seconds. Must be a bug.

50mm1200s

Quote from: Kanakori on June 14, 2018, 11:53:09 PM
By raw rec I meant mlv_lite! I'd still like to try out the h264 with high bitrate though, he quality might increase alot.

Ah, cool.

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I remember being able to record continuously on 60fps with crop rec however at this moment It keeps hitting the red whenever I try it, only giving me about 15 seconds. Must be a bug.

Not a bug, the card and bus interface is too slow to record 1080p at 60fps. Maybe with the uhs module and more compression (10-bit) I might be possible to record continuously.

Kanakori

Ok thanks. I got it to go around 30 seconds, I can work with that...
Still can't find the bit rate option though. It doesn't show up on the video menu contrary to some videos and old threads I looked up. I'm using the crop_rec 4k build on 1.2.3. It seems like a good alternative to shoot with the 5d m3 if the quality of h264 increases.

Kanakori

It allows me to shoot 60fps continuous at 1600 x 680. Honestly it doesn't seem too bad. I'm guessing the stretch will be unotieceable.