EX1 SDI-OUT at INCORRECT FRAME RATE

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drechtaber

New member
hey there.
thanks for taking the time to read this.
i have done a lot of reading in a lot of different forums but am surprised that this issue has not been discussed...or perhaps i have done something incorrect along the way resulting in this current quagmire.

i was shooting some blue screen tests on my EX-1 yesterday.
in order to get UNCOMPRESSED 10-bit footage for the POST-FX guys to work with, we used the HD-SDI out on the camera.
the BNC cable went into an AJA I/O unit which was then hooked up to a MAC running final cut pro.
the data guy would do a 'capture now' and we would get individual clips stored onto the hard drive.

the camera was set to 1920/1080 24frames mode, but the AJA box was reading the signal coming in at 29.97fps.

i wasn't worried at the time, as i had read beforehand (yes, i did the research going in) that the EX-1 spit out a 60i signal that was stable enough (with the positioning of the frames) that it could be easily reverse-telecined back to 23.98 fps.
at the time, i wasn't too concerned about the signal being 30i instead of 60i as i know that those two descriptors are sometimes used interchangeably depending if someone is talking about FRAMES or FIELDS....the data guy said he's only seen 29.97 footage coming off the EX-1 in the past, so i took his word on it....
WAS I WRONG TO?

when i perform a reverse-telecine now, the audio and visuals match up well at 23.98fps, but the picture is HEAVILY interlaced....
i tried to DE-INTERLACE the footage, and while it did get rid of the interlacing, i can VISUALLY tell that the motion in the picture is not 100% smooth.

shooting SDI-OUT from the EX-1 is supposed to be the best quality footage...so there MUST be a workflow that guarantees better results than the ones i have gotten.

does anybody have any suggestions???

thanks in advance for your time......

-zik
 
I'd suggest the AJA is the issue. 1080/23.98P comes out the HD-SDI as 1080/59.94i, unless you have Genlock set to 24P, in which case it comes out as 1080/24PsF.

It could be the AJA thinks 1080/59.94i is 1080/29.97PsF? I'd look into forcing the AJA to what it should be, and see how that goes. Or set Genlock to 24P and see if it handles that properly.
 
the uncompressed quicktimes had a weird frame repeating pattern : not the 3:2 we were expecting.

we were getting a weird pattern: 3 repeating frames then 3 single frames then 3 repeating frames then 3 single.....etc....

it was bang-on this pattern, but my POST guy says he can't remove this with any pulldown technique as the cadence cannot be recognized.

WHAT DID I DO WRONG????
 
does this pattern have anything to do with 'ADVANCED PULLDOWN' ... my post guy says it MIGHT.
i tried bringing the clips into FINAL CUT and adding them to the timeline. i selected a clip and tried to select the 'REMOVE ADVANCED PULLDOWN' option for the TOOLS menu but it was greyed out.....
 
Another reason why I almost never shoot 24p when I'm gonna be staying in a 30fps world. What works flawlessly for us when we shoot Greenscreen is RGB from the EX1 into an Intensity Card in a Mac. We can even do "RealTime" greenscreen with this signal which is uncompressed 4:2:2 and much easier to key.
 
but frank,

we want to be in the 24 (23.98) frame world ever so badly.
the only reason we have 29.97 footage is because we wanted uncompressed and were forced into it by the limitations of the SDI out.

i think devnull is right and the AJA box thought the 60i signal was 29.97i and told the computer as much....but if that's the case, do i have to reshoot????
the post house can't do anything with the interlaced footage and every reverse telecine process i try gives me 23.98 footage that is still interlaced.

booo me!
 
The AJA won't do uncompressed HD, only ProRes HD. The box (and firewire connection) aren't fast enough to keep up with uncompressed 10-bit HD. It will do uncompressed 10-bit SD, but not HD. Could that be your issue?
 
I was told the AJA IO HD can ingest uncompressed and convert it to ProRes(HQ) no problem. Sounds like a configuration problem. Having Genlock would have helped though.
 
My mistake. You're correct you can connect the EX1/EX3's 10-bit 4:2:2 uncompressed HD-SDI signal to the back of the AJA Io HD. It will accept that signal, no problem. But if you want to RECORD 10-bit 4:2:2 uncompressed in HD using the AJA Io HD, then you'll have to do it using the compressed Apple ProRes HQ format. In my experience it is "visually lossless" and looks great. It also holds up well to color grading, etc... But the ultimate would be to capture 10-bit uncompressed in HD, but you better have plenty of bandwidth and hard drive space. :)
 
devnull said:
I'd suggest the AJA is the issue. 1080/23.98P comes out the HD-SDI as 1080/59.94i, unless you have Genlock set to 24P, in which case it comes out as 1080/24PsF.

It could be the AJA thinks 1080/59.94i is 1080/29.97PsF? I'd look into forcing the AJA to what it should be, and see how that goes. Or set Genlock to 24P and see if it handles that properly.
Click to expand...


this may sound silly, but how do you Genlock to 24P on the EX1?

thanks.
 
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