BMCC 6K with Anamorphic 1.8x need help

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Ben-11

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BMCC 6K with Anamorphic 1.8x need help

PostThu Nov 30, 2023 6:33 pm

Hello everyone, I have recently purchased the Blackmagic Cinema Camera 6k and a BLAZAR LENS Great Joy 50mm T2.9 1.8x Anamorphic Lens. I am trying to Figure out what resolution to shoot in and what settings to use in post production. I have been spending the past week trying to figure this out but am still at a loss and confused on the settings to use.

I have been shooting in the open gate 3:2 aspect ratio at the full 6064x4032 resolution with a 1.8x squeeze of the lens. Is that the the optimal resolution to use on the camera with that 1.8x squeeze factor in terms of maximum quality? Also why is there only a 1.6x anamorphic de-squeeze preview option on the camera at that resolution and no 1.8x?

The second part of the question is when importing that footage in Davinci Resolve. The Blackmagic raw footage obviously has the 1.6x setting as a preset on the footage since I have no other option when using the camera at that resolution. When I select the clips attributes and change the pixel aspect ratio to 1.8, I see black bars at the top and bottom of the clips appearing. Does that mean I am not utilizing the full area of the sensor at 1.8x at open gate (6064x4032)?

Also, I have been trying to figure out what to set a correct timeline resolution and image scaling tab settings in the project settings in order to have the footage appear correctly and without getting black bars when exporting. I have seen videos in which people decrease the vertical resolution in order to get rid of the black bars and select stretch frame to all corners in order for the image to appear correctly. I would have to decrease the vertical resolution to something like 6064x2500 (approximately) but am I not decreasing and loosing vertical information by doing that when exporting? that would bring the megapixel count down to around 15 megapixels. I also found an article on a "reputable" website which said that to not loose any resolution you have to increase the horizontal resolution to get the proper proportion, that would bring my resolution to 10915x4032 (45 megapixels). I understand I am not gaining quality by doing that since the sensor is only 24 megapixels. Working with that resolution is a nightmare in resolve but I can always change that at the end when exporting footage. I don't want to downscale my footage by reducing the vertical resolution when exporting. What is the proper way of working with a 1.8x anamorphic squeeze without loosing resolution during export?

Do I just keep the original resolution of 6064x4032 when exporting and change the viewing aspect ratio within the media player itself which is used to view the footage in order to de-squeeze ? Do I Increase the horizontal resolution or decrease the vertical resolution?
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rick.lang

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Re: BMCC 6K with Anamorphic 1.8x need help

PostFri Dec 01, 2023 2:21 am

What standard horizontal resolution is required for your deliverables? That will guide your approach? What subjects would you typically be shooting?

I typically deliver UHD because almost everyone outside of cinema will be viewing on a device that benefits from 3840 columns. I also prefer delivering 2:39:1 aspect ratio which works well visually for my subject matter as my vertical information requirements are a lower priority than the demands for horizontal coverage. So I deliver 3840x1608 or 4096x1716.
Rick Lang
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Ben-11

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Re: BMCC 6K with Anamorphic 1.8x need help

PostFri Dec 01, 2023 7:06 pm

Hello rick thank you for taking the time to help me out, I really appreciate it.

I am just filming for myself currently, I am trying to learn how to make use of the anamorphic process. I have no deliverables in mind for now. But I tend to shoot people and landscapes. I guess I am trying to understand what settings to use both on camera and post in order to export without the loss of resolution. Thanks.
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focuspulling

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Re: BMCC 6K with Anamorphic 1.8x need help

PostThu May 16, 2024 8:29 am

Surprised to see so little discussion here about FF open gate with this lens. How is the vignetting?

Wondering if this test was flawed:
Paul Moon | FocusPulling (.com) | On the art & technology of filmmaking
www.focuspulling.com | facebook.com/focuspulling | @focuspulling
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Dan Cotreau

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Re: BMCC 6K with Anamorphic 1.8x need help

PostThu May 16, 2024 2:56 pm

Let me start by saying I am no expert on this topic at all. In fact I too find it all a bit confusing.

This may or may not be helpful. But here is an anamorphic ratio calculator that a young filmmaker created online. And I also attached a youtube video of how he applies this within different editing platforms. Hopefully this might be somewhat helpful.

Calculator: https://www.tferradans.com/blog/aspect- ... alculator/


Video:
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rick.lang

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Re: BMCC 6K with Anamorphic 1.8x need help

PostFri May 17, 2024 3:45 pm

You can follow that calculator and apply values as illustrated if you wish. I don’t use the app or alter the Edit zoom value for the horizontal axis. I do squeeze the vertical axis with a value that’s the inverse of the anamorphic lens squeeze factor.

For example:
1) camera recording 4096x2160 DCI with a 2x anamorphic squeeze of the horizontal axis

2) deliverable will be 4096x1716 2.39:1 aspect ratio

3) project settings 4096x1716 4K widescreen
4) project settings scaling Centre No Crop

5) Edit page zoom - deselect the X-Y link

6) Edit page zoom - enter inverse of the squeeze factor 1 / 2x = 0.5x

You’re done.

You should maintain your horizontal pixel count as a standard with such as 1920, 2048, 3840, 4096, etc. The lines of resolution can be pretty much anything but will reflect the desired aspect ratio.
Rick Lang

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