New Hack and 2x anamorphic questions.... 1920x1440 ... 960 x 405 ...possible?

C

CRFilms

Active member
I bought a 2x anamorphic lens years ago and recently found it. It seems like that's one of the oddest multipliers for trying to get it to work without cropping. There's been talk of how it might work with the new patch, but i'm wracking my brain trying to do the math and here's my questions....

1920 x 1410 = 4:3 ratio i.e. super size standard tv
960 x 405 = HD ish 2:35 ratio for 2x adapters ...?
1280 x 960 other HD ish 2:35 ratio for 2x adapters ...?

1920 divided by 2 = 960

I divided 1920 by 4 and that gave me 480. I then multiplied that by 3 and it gave me 1440. So then....is it possible to record 1920 x 1440? A 4:3 ratio Granted when you stretched that out it would give you 3840 x 2880...a number I can barely comprehend, but for the sake of argument, can the GH1 record 1920 x 1440?

Going back up to the first number...810 is the second number that give you about a 2:35 ratio when 1920 is the first. So divide 810 by 2 and that give us 405. Can the GH1 record 960 by 405? What about 1280 x 960?

Can it come close? Is my math way off? Help
 
Congratulations to Vitaliy, not only for cracking the v1.34 firmware with PTool 3.55d, but for the new patches that enable modification of both frame size and quality settings in the GH1's MJPEG VGA mode. This video mode's standard frame size is 640x480, equivalent to NTSC SD resolution. With PTool 3.55d, this frame size can be patched to any dimensions up to 1920x1080. However, the VGA mode's SD-resolution 4:3 aspect ratio still applies to the patched dimensions. If you actually set a 1920x1080 frame, it would be horizontally squeezed into a 1440x1080 aspect ratio, which is an anamorphic ratio of 1.33X. If you used this frame size with a 1.33X anamorphic adapter, such the Panasonic LA7200, it would produce a 1920x1080 video frame in the correct aspect ratio in MJPEG VGA mode. While this may seem redundant, it's one way to produce anamorphic bokeh and flares in FHD resolution (though of course it would still be recorded at MJPEG's 30fps).

An even more interesting application of the new VGA mode is using it to support shooting with 2X anamorphic adapters. In the GH1's 16:9 HD mode, these lenses would produce an excessively wide frame size of 2560x720. Setting the 3:2 VGA mode to 1920x720 produces the perfect anamorphic ratio for use with 2X anamorphic lenses. These videos can be viewed straight out of the camera in the correct aspect ratio, with no need for post-processing.

For those who'd like to try this new 2X anamorphic mode, I recommend patching the VGA mode quality settings with the values used in my MJPEG Anamorphic Cinemascope Patch. I've gotten reliable results from these settings in at a frame size of 1920x810 in HD mode (with 1.33X anamorphic lenses), and they appear to work just as well at 1920x720 in VGA mode in PTool 3.55d. Here is a list of the patch settings, which can be appended to existing PTool INI files:

480p30 width=1920
480p30 height=720
F1 Quality=280
F1 Table=4
F2 Quality=250
F2 Table=10
F3 Quality=225
F3 Table=24
F4 Quality=200
F4 Table=48
 
I read that in Vitaliy's forum but I can barely understand my math, nevermind yours. ;P

Although maybe.... 1920 / 720 = 2.66

But then what about shooting though a 2x lens? Doesn't that make it 3840 x 1440, but that also equals 2.66....

So does that mean once you put that 1920x720 into your editing program and make the clip settings 2x, that will make the correct stretch in a 1080p timeline/workflow?

Now I see where I'm messing up...I'm multiplying 2 across the board, when it should only multiply the horizontal, ie, the 1920.

So that should be 960 x 720....The 720 stays the same cause it's only a horizontal squeeze. So again...can the MJpeg settings be set to ANY width between 1920 and 960 and can the height be anything between 405 and 1440?
 
Is there a choice to change the frame dimensions within the patch? Or does it become a camera menu choice after the patch?
 
I just did a quick test 1280 x 960 worked. It recorded using these settings:

480p30 width=1280
480p30 height=960
F1 Quality=280
F1 Table=4
F2 Quality=250
F2 Table=10
F3 Quality=225
F3 Table=24
F4 Quality=200
F4 Table=48

I can't do a real vid because my 2x lens doesn't have any adapters and I just held it up by hand and it was beyond shaky. If somebody has a 2x lens that's properly mounted to their cam could you do a test with that setting and see how it looks?
 
Here's the best screen grab I was able to get. Both the lens and anamorphic lens had to be focused seperate and it was near impossible to focus the 2x while holding it by hand up to the lens.
2xAna.jpg

1280 x 960 then converted to regular 1080p with the file pixel aspect ratio at 2. I think this could be doable.

EDIT: 960 gives a 2.66 ratio, for a 2.35 ratio you'd need 1280 x 1090.
 
Last edited:
@CRFilms

you are doing this way too complicated. 1280x960 is an aspect ratio of 4:3 (because 1280*3/4=960) which lets you record videos in correct aspect WITHOUT any adapter. Of course you can stretch it in post, but the resolution still is "only" 1280x960.

Just do it as LPowell said. Set the VGA Mjpeg mode size to 1920x720. This stretches the video to an aspect ratio of 2.66:1 which is the right for an 2x adapter. No need for any converting, stretching or anything else in post. Just open the file and be lucky, cause everythings correct.
 
Son of a gun....LPowell is right...when the camera records in that 1920x720 it doesn't crop the standard image, it warps it also. I just did a test of his settings and without the 2x lens everything look way fat, then when I put the lens on, it looked normal.

1920x720 it is.
 
How is this different than changing the size to 1920x720 in the standard HD mode? That's the only thing I don't understand.
 
For some reason, when you do the settings lpowell said the camera records the image warped. Like this:
2xana4.jpg

But when you put a 2x lens in front it looks like this

2xana3.jpg


Pardon the quality, I held the lens up to the cam by hand since I don't have any adapters/connectors for it.

It warps the image in cam unless you shoot through an adapter. I didn't get it till I saw it myself.
 
I know that, but doesn't changing the standard HD mode of mjpeg also warp the image? I guess I'm just confused as to why the VGA mode is so special. Is it because it's squeezing the image into a 4:3 frame instead of a 16:9 frame? By the way, how is focus pulling with that 2x lens? I hear you have to focus both lenses *has nightmares*.
 
tommygdawg said:
...I'm just confused as to why the VGA mode is so special. Is it because it's squeezing the image into a 4:3 frame instead of a 16:9 frame?
Click to expand...
Yes, that's the crucial difference between the hacked VGA and HD modes. At 720p resolution the VGA mode produces square pixels when its width is set to 960. That's why you double the width to 1920 for use with a 2X anamorphic lens. Likewise, at 810p resolution the HD mode produces square pixels when its width is set to 1440. To use it with a 1.33X anamorphic lens you multiply that width times 1.33 to produce 1920.
 
lpowell said:
Yes, that's the crucial difference between the hacked VGA and HD modes. At 720p resolution the VGA mode produces square pixels when its width is set to 960. That's why you double the width to 1920 for use with a 2X anamorphic lens. Likewise, at 810p resolution the HD mode produces square pixels when its width is set to 1440. To use it with a 1.33X anamorphic lens you multiply that width times 1.33 to produce 1920.
Click to expand...

My brain just exploded, who wants to clean it up?
 
I guess I'm jumping in here in the middle. Is there a mode where we can get XXX x 1080p? Square pixels? This would give a higher horizontal resolution than an LCD TV can display, but then you have some room to use some stabilization like Warp Stabilization in After Effects where you loose on the crop, but you'd still have more pixels then you'd need to get to a 1080p resolution. Letterboxed of course. Damn, I want an anamorphic lens!!!!

Also, what is the frame rate limited to. as MJPG 30p? Also 60p but no 24p?
 
CRFilms said:
Son of a gun....LPowell is right...when the camera records in that 1920x720 it doesn't crop the standard image, it warps it also. I just did a test of his settings and without the 2x lens everything look way fat, then when I put the lens on, it looked normal.

1920x720 it is.
Click to expand...

So our we saying, that with the Anamorphic adapter, the EVF and rear LCD correctly displays the anamorphic frame? That's cool!
 
This is awesome but 30fps is of very limited use to me :(

I know it's asking a lot (maybe more than is possible with the current state of things) but if this could make its way to FHD/AVCHD mode it would be great.
 
Yes come on people, how hard would it be to get the VGA mode to record 24p. Give me high bit rate mjpeg 422 in 24p and native animorphic, is that really too much to ask. How does the quality compare to shooting 1080 24p and doing the unsqueeze/crop/zoom in post, like say working in the FCP anamorphic hd viewers.
 
You must log in or register to reply here.
Back
Top