Anamorphic Cinemascope in Native 1920x810 MJPEG Mode

Nieuw said:
My intention is to produce material in 2560x1080......

As I read and understand(?) this thread one can produce 1920x1080 by software scaling from 1920x810 without any anamorphic adapter attached (also on a GF1)...

Does this mean that if one uses both the software scaling and a 1.33 anamorphic attachment (in the other direction) one would/could get 2560x1080 out of a GF1?? How would the quality look like?

The alternative for the GF1 could be to use 1440x1080 and to use a 2x anamorphic attachment this would produce 2.67 ratio material. However does this recording option work on a GF1??

What would, facing less limitations, be the best solution for the GH1 to produce 2560x1080??
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Testing of extended frame sizes on the GF1 has shown that it's not quite capable of reliably recording videos at FHD 1920x1080 in MJPEG. The next best alternatives are both 1.33x anamorphic frame sizes: 1920x810 (2.37:1) and 1440x1080 (4:3). The widescreen 1920x810 frame works perfectly with a 1.33x anamorphic adapter, producing correctly scaled 1920x810 videos without needing post-processing. I've published a downloadable PTool INI file for this mode that works on both GH1 and GF1 cameras:

LPowell - Anamorphic 1920x810 MJPEG Patch.zip

While the 1440x1080 mode is not directly matched to anamorphic adapters, it can be stretched horizontally in post to restore the correct aspect ratio. With a 1.33x anamorphic lens, it should be stretched to 2560x1080. With a 2x adapter, stretched to 3840x1080 and cropped down to 2560x1080 for 2.37:1 widescreen dimensions.

For best image quality, I've found it advisable to limit upscaling of anamorphic images to only one dimension, either horizontally or vertically, but not both. Naturally, the larger the stretch factor, the lower the resolution of the resulting image. However, 2x anamorphic adapters will produce inherently longer horizontal flare and vertical bokeh effects than 1.33x adapters.

For the GH1, the best option for producing a 2560x1080 widescreen video would be to use a 1.33x anamorphic adapter in FHD 1920x1080 AVCHD mode, stretching it in post to 2560x1080.
 
gf1h4x0r said:
Interesting. 1400x1080p might then be the best choise for the poor GF1 user without the anamorphic adapter....
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It's a judgment call, but I think the vertical stretch of 1920x810 -> 1920x1080 looks better than the horizontal stretch of 1440x1080 -> 1920x1080. Two reasons:

1. Human binocular vision evolved to be more sensitive to horizontal movement than vertical.
2. Decades of interlaced television viewing have trained us to disregard its degraded vertical resolution.
 
lpowell said:
The only way to get a 4:3 ratio is to select VGA mode, which has an unpatchable 640x480 frame. Likewise, the WVGA mode has a fixed 848x480 frame, and the QVGA mode has a fixed 320x240 frame. At this point, only the HD video mode has a patchable frame size. Here's how I suspect this works internally.
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This may be a stupid question but do you know why it is unpatchable? TBH I dont mind having extra footage because I can just throw it in AE and slide back and forth to what I want to see. The biggest issue I see with using a 2x is proper framing on set. I'm thinking of an over the shoulder two shot and not being able to cram it all into the 2.66 aspect.
 
It's not unpatchable, it's just not patched yet.

If you like 3.58 as an aspect ratio, when it allows you to pick that portion of the footage you think looks best, then who can have anything against that?

I don't need 3.58, i would be very happy with 2.66, because i would have a lot less data to deal with and i could shoot 1440x1080 4:2:2 MJPEG, which is not possible with 1920x1080. Though AVCHD looks really nice as well on the hacked GH1.
 
johnnym said:
i would be very happy with 2.66, because i would have a lot less data to deal with and i could shoot 1440x1080 4:2:2 MJPEG.
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Has anyone published stable patch settings for 1440x1080 MJPEG in 4:2:2 color depth? I've done some tests at that resolution and wasn't able to find reliable settings.
 
I didnt play much with 1440x1080 however I noticed an interesting thing with 1280x544 and bitrates with 4:2:2 checked. Bitrates were higher at 1280x544 vs 1280x720 MJPEG in all videos that I took.
 
lpowell said:
Has anyone published stable patch settings for 1440x1080 MJPEG in 4:2:2 color depth? I've done some tests at that resolution and wasn't able to find reliable settings.
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No not yet. I might buy a Sandisk card and see if there's some improvement there.


By the way, i did some testing with Instant HD to see if uprezzing my anamorphic footage would be improved with it, but it's negligable compared to AE's own scaling.
 
Ipowell, a little of topic but do you think mjpeg hacked to 1440x810 would have more resolution than original 1280x720 on the Gf1. whats the current thought on larger sizes. are they just an upscale, or is there more visible resolution? thanks
 
sparedog said:
Ipowell, a little of topic but do you think mjpeg hacked to 1440x810 would have more resolution than original 1280x720 on the Gf1. whats the current thought on larger sizes. are they just an upscale, or is there more visible resolution?
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With a 1440x810 resolution and a non-anamorphic lens, you'll get an undistorted 16:9 aspect ratio that needs no further post-processing. I've tried it and to my eyes it looks better than upscaling a 1280x720 video in After Effects or Premiere. An important factor to bear in mind is that the camera produces the 1440x810 frame before it is encoded into MJPEG format. Any post-processing you do to a 1280x720 video must inevitably work with the compressed MJPEG output of the camera.
 
lpowell said:
An important factor to bear in mind is that the camera produces the 1440x810 frame before it is encoded into MJPEG format. Any post-processing you do to a 1280x720 video must inevitably work with the compressed MJPEG output of the camera.
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yes that is an interesting thought and one that never crossed my mind.

do you think that shooting a res chart like ones found at the link below - could be used to test the 2 outputs? or will it not tell me anything. if so i'll hack one of my gf1 to 1440 and keep the other at 720 and shoot the chart.

http://www.bealecorner.org/red/test-patterns/
 
i'd say by those tests there's way more resolution. great i dont need to do the tests.

the more i see of this 1920x810 hack, the more i like it! great work :D
 
one other thing, as my computer is a netbook, and ptool is actually too big to be seen entirely on a netbook screen, i cannot access the presets of ptool. is there any chance you could direct me to a written version of the 1920x810 settings. sorry to be so screen impaired lol
 
Any more word on whether a 4:3 might be possible on the GH1? I've been slack in following forum developments for a while but I'd love to shoot 2.66:1 with my 2X Kowa someday.

Dirty secret: I kinda want to shoot native 4:3 without the adapter, too :)
 
Oh no, you want to shoot rectangular???? :grin:

I'm praying every day for a new PTool with 4:3 1440x1080p. You think it would help?

Gorgeous anamorphic footage, Oedipax.
 
for the LOMO anamorphic lenses (2x) and GH1 what is the better mode to go with?
record in standard then unsqeeze and crop in post to 2.37:1
or what mode will give unsqeezed monitoring in camera and 2.37:1 in post?
 
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