Anamorphic Cinemascope in Native 1920x810 MJPEG Mode

juud said:
Hi omnidecay,
This is the sample of my 1920*540 patch. No anamorphic attachment in this vid, though.
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Click to expand...

Nice I see what you mean with the white line. I have never seen that on any of the footage I have captured so I wonder what could be causing it...

Johnny: The link didnt work for me but I get the jist from your post. I was looking around for other cameras that were capable of high resolution 4:3 and there are not a ton to pic from (I think I found 2). I really think the gh13 would be the only camera in its price range or even close that could output 2.66 with such a good image. I have an email in to Vitality but he hasen't responded. I'm sure he is a really busy dude but besides that the GH2 is pretty much available now not to mention the HDMI out he was trying to get working.

One idea what I have been thinking about was to try to use the small c-mount lenses with the anamorphic 2x. They would all vignette but since we would need to crop a ton anyways they might work. Of course the problem of loosing resolution still sucks.
 
I think the C-mount lenses could work, given the focal length is high enough. What i'm not sure of though, is whether there's a difference between c-mount for 8mm or 16mm film. I would think the 8mm coverage wouldn't be sufficient at any focal length, but -as i said- i know too little about c-mount lenses to say anything certain about it.
Look here (i think it looks really good) : http://vimeo.com/16335998

Maybe we should all massively donate for vitaliy's time, tinkering with the 4:3 mode.
 
Just thought i share some screen caps, shot with GH13, 14-45mm, Century Optics Anamorphic 1.33x and Ipowell's patch. No touch ups at all, and very improvised due to the wet weather.

5217822503_5ff46a7be6.jpg


5217822217_9569df80ce.jpg


5218409908_a2c514734d.jpg


5217820643_aca7833f0b.jpg
 
raymondluo said:
Just thought i share some screen caps, shot with GH13, 14-45mm, Century Optics Anamorphic 1.33x and Ipowell's patch. No touch ups at all, and very improvised due to the wet weather.

5217822503_5ff46a7be6.jpg


5217822217_9569df80ce.jpg


5218409908_a2c514734d.jpg


5217820643_aca7833f0b.jpg
Click to expand...

Man those look great! Do you have a vid posted anywhere yet? I would love to see something more than tests shot with this setup.
 
nice one

nice one

Given that it's shot with the 14-45mm i think it looks really good.
Did you get less softness at the sides when shooting at 45mm or at a lower f-stop?
 
The 14-45mm is actually a superb yet underrated lens, which I chose over the 14-140mm. If you think about it, other than compactness, the 14mm 2.5 offers little more that the 14-45mm piece can't provide. At 14mm, with a F3.5, i can see it handling virtually the same in situations of low light with it's MEGA O.I.S., quite possibly even better depending on how you quantify the weight of f-stop versus stops of stabilization. I see myself in the future getting another piece of this just in case it breaks down. It's been discontinued so grab it where you can!

Yes the softness does fade with a narrower f-stop and a longer focal length.
 
All 1/30, ISO 640, nostalgic -2,-2,-1,+2
AVCHD 24pN 50,100. MJPEG all Q800, T0.
MJPEG 1920x1080 4:2:2 checked size 932 kB, 1920x1080 photo size 919 kB.

AVCHD 1080p 24pN

MJPEG 1920x1080

MJPEG 1920x810 --> 1920x1080

MJPEG 2048x1152

MJPEG 1920x1080 4:2:2 checked

MJPEG 1280x720 4:2:2 checked --> 1920x1080

1920x1080 16:9 photo


AVCHD 1080p 24pN

MJPEG 1920x1080

MJPEG 1920x810 --> 1920x1080

MJPEG 2048x1152

MJPEG 1920x1080 4:2:2 checked

MJPEG 1280x720 4:2:2 checked --> 1920x1080

1920x1080 16:9 photo
 
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johnnym said:
Can anyone explain how this guy shot 1440x1080 on the GH13? Does that mean it is possible after all to shoot at this aspect ratio (4:3) at HD resolution?
Click to expand...
GH1/GF1/G2 can be set to record in MJPEG in 1440x1080 using the same patches that produce 1920x810 mode. However, all HD video modes are based on a 16:9 isomorphic frame size.

Both 1440x1080 and 1920x810 can be technically described as anamorphic modes, and they happen to be exact inverses of each other, with a 1.33x pixel aspect ratio. 1440x1080 (1.33x) is the format used by many HDV camcorders, because it was the highest resolution that could be recorded to digital videotape. This format contains metadata that indicates the 1.33x pixel aspect ratio, which causes it to be automatically stretched to 1920x1080 when displayed in a video editor or player.

When the GH1 records a non-standard MJPEG frame size, it writes that frame size as metadata into the video file, which causes it to be displayed at those specified dimensions. However, since the GH1 always records its pixel aspect ratio as 1:1, anamorphic frame sizes are not stretched in playback. Thus, if you set a 1440x1080 frame size, it will be displayed as exactly that, with a distorted image that needs to be stretched to 1920 pixels wide to have the correct 16:9 aspect ratio.

The beauty of the 1920x810 frame size is that it works perfectly with a 1.33x anamorphic adapter. The lens' 1.33x horizontal squeeze factor matches the anamorphic mode's 1.33x horizontal stretch, producing a correctly proportioned 1920x810 video in playback.
 
lpowell,

while your explanation is technically accurate, for some reason (unknown to me) it doesn't seem to apply to the image i linked to : there is NO distortion at 1440x1080, hence the aspect ratio is a native 4:3, but i can't seem to figure out why.

Was there an option in the earlier stages of PTool, that allow MJPEG 4:3 1440x1080p, but has since been removed from the PTool?
 
johnnym said:
Was there an option in the earlier stages of PTool, that allow MJPEG 4:3 1440x1080p, but has since been removed from the PTool?
Click to expand...
No, the HD video mode has always used a 16:9 aspect ratio. 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:

The source frame is defined in terms of the 12 megapixel RGBG Bayer Filter array. For HD and WVGA 16:9 modes, this is a 4000x2248 array on the GF1/G2, but on the GH1 it is a 4352x2448 array. For VGA and QVGA modes, it is a 4000x3000 array on all three cameras.

In MJPEG video modes, the RGB video frame is downscaled from the RGBG source frame to the specified video frame size for each of the four video modes. In HD video mode, the original firmware is set to produce a 1280x720 video frame. With PTool 3.5, we can patch this to any horizontal and vertical frame size up to a maximum of 1920x1080. The original HD source frame however, is fixed at a 16:9 aspect ratio. This is why a non-16:9 patched frame size produces an anamorphically scaled image.
 
Dear All,

I am new in this field but got fascinated by the subject. I meanwhile do have a number of anamorphic adapters (both 1.33 and 2x) but unfortunately very little time to play with them, I also have a GF1 and a GH1 camera.

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?? (any examples around??) It would be an extremely compact option to produce 2.37 ratio material.

The alternative (less compact option) 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??

Are my assumptions correct??
Which of the two options would be the best way to go forward??
Which software could perform the proper scaling??
What would, facing less limitations, be the best solution for the GH1 to produce 2560x1080??


Thanks in advance,

Hans van Nieuwkerk
 
From what i know, 1440x1080 isn't available in PTool.

Your best chance to produce 2.37 is to use an 1.33x anamorphic on the 16:9 image you get out of the GH1/GF1.
It's not possible to output 2560x1080 from the GH1, because you won't be able to record due to errors. You will have to input lower resolutions in PTool for MJPEG recording, but you can input any aspect ratio you want including 2.37. Whether it is best to do this in-camera, or in post, remains a subject for debate.
 
lpowell said:
No, the HD video mode has always used a 16:9 aspect ratio. 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:

The source frame is defined in terms of the 12 megapixel RGBG Bayer Filter array. For HD and WVGA 16:9 modes, this is a 4000x2248 array on the GF1/G2, but on the GH1 it is a 4352x2448 array. For VGA and QVGA modes, it is a 4000x3000 array on all three cameras.

In MJPEG video modes, the RGB video frame is downscaled from the RGBG source frame to the specified video frame size for each of the four video modes. In HD video mode, the original firmware is set to produce a 1280x720 video frame. With PTool 3.5, we can patch this to any horizontal and vertical frame size up to a maximum of 1920x1080. The original HD source frame however, is fixed at a 16:9 aspect ratio. This is why a non-16:9 patched frame size produces an anamorphically scaled image.
Click to expand...


Yes it must be squeezed.
 
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