XHA1 'LIVE' analog outs are 1080x1920 or 1080x1440?

[Lonnie Bell]

Khoi,
thanks so much...

where/how do you set the 1:1 ratio for this test?

Thanks again,
Lonnie

[Khoi Pham]

Go into your menu and choose Image Settings/Scalling and choose 1:1

[Lonnie Bell]

Thanks Khoi - you are THE MAN!

Lonnie

[Bill Busby]

I was looking at this thread & have little to add, but was hoping someone could help with something I'm a tad confused about. The Dell 2405's optimal rez is 1920x1200... that isn't 16x9... it's 16x10. How would one get proper 16x9 aspect ratio with component connections? I don't own a 2405 but a friend does, so I can't really sort this out myself :D Would this be the 1:1 setting mentioned?

Bill

[Thomas Smet]

Does it really matter what it is doing? I mean when hooked up is anybody really going to notice and say the video looks like it was 1440x1080 instead? The 1440x1080 on the HD cameras is anamorphic which means when you view it on a HDTV it is going to look as if it was 1920x1080. The only difference is that the 1440x1080 version may be slightly softer due to the anamorphic pixels. Almost every single HD tape format works this way. HDCAM also uses 1440x1080 and DVCPROHD uses either 960x720 or 1280x1080 pixels depending on if it shooting 720p or 1080i material. So HD material you watch on NBC, ABC, CBS, FOX and any HD cable channel comes from a anamorphic pixel resolution. Thats just the way it is.

It is almost impossible to tell the difference between 1440x1080 and 1920x1080 unless you start to mathmatically analyze the pixel values.

If you are hooking up your camera to a LCD monitor via component it will always look correct because the camera outputs the anamorphic pixels as a 1920x1080 shape to display.

I doubt anybody could ever even tell if the signal was 1920x1080 or 1440x1080.

Just to note that the chips are 1440x1080 pixel chips. The chips however do use pixel shift to help get back some of the detail to bring the resolution closer to 1920x1080 pixels. I cannot remember if the live outputs pump out this 1920x1080 or not but again it doesn't really matter. It isn't going to make a huge difference and if anything it will only give you a tiny tiny tiny edge in sharpness in the overall image.

[Khoi Pham]

Originally Posted by Bill Busby

I was looking at this thread & have little to add, but was hoping someone could help with something I'm a tad confused about. The Dell 2405's optimal rez is 1920x1200... that isn't 16x9... it's 16x10. How would one get proper 16x9 aspect ratio with component connections? I don't own a 2405 but a friend does, so I can't really sort this out myself :D Would this be the 1:1 setting mentioned?

Bill

Yeah this would be 1:1 scalling, it will be 16X9, but since the monitor is 1920X1200, it won't use the extra 120 pixels and won't fill up the whole screen, it will be black on top and bottom.

[Bill Busby]

Thanks Khoi.

[Lonnie Bell]

Originally Posted by Thomas Smet

Does it really matter what it is doing? I mean when hooked up is anybody really going to notice and say the video looks like it was 1440x1080 instead? The 1440x1080 on the HD cameras is anamorphic which means when you view it on a HDTV it is going to look as if it was 1920x1080. The only difference is that the 1440x1080 version may be slightly softer due to the anamorphic pixels. Almost every single HD tape format works this way. HDCAM also uses 1440x1080 and DVCPROHD uses either 960x720 or 1280x1080 pixels depending on if it shooting 720p or 1080i material. So HD material you watch on NBC, ABC, CBS, FOX and any HD cable channel comes from a anamorphic pixel resolution. Thats just the way it is.

It is almost impossible to tell the difference between 1440x1080 and 1920x1080 unless you start to mathmatically analyze the pixel values.

If you are hooking up your camera to a LCD monitor via component it will always look correct because the camera outputs the anamorphic pixels as a 1920x1080 shape to display.

I doubt anybody could ever even tell if the signal was 1920x1080 or 1440x1080.

Just to note that the chips are 1440x1080 pixel chips. The chips however do use pixel shift to help get back some of the detail to bring the resolution closer to 1920x1080 pixels. I cannot remember if the live outputs pump out this 1920x1080 or not but again it doesn't really matter. It isn't going to make a huge difference and if anything it will only give you a tiny tiny tiny edge in sharpness in the overall image.

Hi Thomas,
and thanks for bringing even more knowledge base to this...
My intentions and reasoning are my eventual workflows. If I can purchase the less expensive XHA1 and string the component outs to the IO HD, transcoding uncompressed analog to ProRes422, and stay there until output - this would be a great, relatively inexpensive solution for an uncompressed field capture since the transcode to ProRes422 is high quality (like Cineform) and no raids needed in the field. Which leads to the question - what is the quality and resolution of the uncompressed analog outs of the A1...

We know this can be done via an all digital route with HD-SDI and the G1, but the added costs to this is the same amount spent on Aja's IO HD. Thus, the questions about analog uncompressed - and if it was pumped out 1080x1920... (and a horizontal hit from 1920 to 1440 is 25%...) However, your real world experience does buffer this a bit if you tell me it's almost undecernable...

Any others care to give their oppinion here - I do truly value your input since all I have next to me is my XL2...

Thanks,
Lonnie

[Nate Weaver]

Pixel dimensions only apply for digital signals.

To ask whether the horizontal dimension of the analog output is 1920, is to not understand how analog signals work.

The more accurate question would be to ask if the analog output is derived from a 1920 internal raster or 1440. Since the CCDs do not have 1920 horizontal photosites, even this question is more or less moot...the analog signal could not be composed of more than 1440 horizontal samples.

[Lonnie Bell]

Nate - I like your brain.

Then let me ask you, do you think the signal from the A1 is pumped up or processed off the 1440 rastor prior to the component out to be 1920? or do you know if it is just the pure 1440 raster sample out of the component?

Thanks,
Lonnie

[Chris Hurd]

Keep in mind that it ain't just the "1440 rastor output." Sure, each CCD is 1440 pixels wide, but don't forget, there's a very effective resolution boost provided by the Pixel Shift process in the horizontal axis. What happens at the CCD level and what happens at the output are two different things... it's not 1:1. Pixel Shift puts the horizontal resolution up in the neighborhood of 1920.

[Lonnie Bell]

Originally Posted by Chris Hurd

Keep in mind that it ain't just the "1440 rastor output." Sure, each CCD is 1440 pixels wide, but don't forget, there's a very effective resolution boost provided by the Pixel Shift process in the horizontal axis. What happens at the CCD level and what happens at the output are two different things... it's not 1:1. Pixel Shift puts the horizontal resolution up in the neighborhood of 1920.

thanks Chris... and assuming you read my proposed workflow - uncompressed component out of A1 to IOHD (transcoded to ProRess422) into FCP, in your opinion would this "signal pumping" component analog out be quantitatively/subjectively/objectively as close as the G1's hd-sdi out? ...huh? :)

[Chris Hurd]

I don't know as I've never tried it. I'm perfectly happy with HDV, so I've never seen a reason to capture by any other way but FireWire.

[Thomas Smet]

What I suggest is to get your setup and then capture a few test clips at 1920x1080 resolution and 1440x1080 resolution and compare the two. Checking out the footage yourself will be much better then anybody on this forum telling you with words how it will look. Only you can decide how well the footage will look.

[Lonnie Bell]

yeah Tom I agree, but these are PRE-purchase questions before I plunk down 7k on camera and IO HD - that would be a large investment for a test and then only to be possibly disappointed...

so, I'll probe a little more than go for it... probable outcome: get the A1, see how HDV and Firewire work for me in FCP Studio 2... check out software transcode of HDV to ProRes422 in FCP... then consider Aja's IO HD among others if I feel I have a need for a higher field capture codec workflow...

Lonnie