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ioHD Conversions 1080p30 or 1080i29.97

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Jim Wiseman
ioHD Conversions 1080p30 or 1080i29.97
on Feb 24, 2009 at 6:35:11 pm

I'm shooting for 3 weeks at a remote location. I would like to use the ioHD for as many of the conversions as possible to keep costs down. I am trying to decide whether to shoot in 1080p30or29.97 or 1080i29.97. I don't particularly like the look of 24p. I do want to keep delivery options open as much as possible though, which will be web, 1080i broadcast/cable, and NTSC SD for sure. Don't want to close off PAL distribution, either, but that is not immediately important. Which is easiest to cross convert to the above formats with ioHD? Would both of the formats be difficult to get to PAL? Of the two, which would you choose? Should I bight the bullet and shoot 24p, even though I'm not fond of the hassle with keeping motion artifacts under control? Any thoughts would be greatly appreciated.

Jim Wiseman


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Jeremy Garchow
Re: ioHD Conversions 1080p30 or 1080i29.97
on Feb 25, 2009 at 6:00:04 pm

Shooting 24p and converting to PAL is a pretty simple conversion, but it's also possible to shoot 1080i29.97 and get to 1080i25 with an external hardware conversion.

Shooting 1080psf30 to PAL is a much harder conversion and altough possible, I think there are better options out there.

Jeremy


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Jim Wiseman
Re: ioHD Conversions 1080p30 or 1080i29.97
on Feb 25, 2009 at 11:35:12 pm

Thanks Jeremy.

That just about makes up my mind to stick with 1080i60.

One other possibility raises its head though. What about shooting 1080p30, converting to 1080i60 with ioHD in Final Cut or via EX-1 SDI out direct (supposed to be 1080i out)in to ProRes HQ, and at some point going to PAL from there? Does that make any sense or would the double conversion (ioHD/externtal hardware device) lose too much quality?

Thanks again in advance.

Jim Wiseman


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Jeremy Garchow
Re: ioHD Conversions 1080p30 or 1080i29.97
on Feb 26, 2009 at 5:36:39 am

[Jim Wiseman] "What about shooting 1080p30, converting to 1080i60 with ioHD in Final Cut or via EX-1 SDI out direct (supposed to be 1080i out)in to ProRes HQ, and at some point going to PAL from there? "

If you record 1080p30, it will really be 1080psf30 which is 30p in a 60i stream. So the same rules apply as before. The ioHD won't help you in this case, it will just record the 1080psf stream. It will be up to you to get the conversion done in hardware or software and you should test test est.

If I were you, I'd shoot 24p as it makes a 'Universal' master. From 1080psf23.976, you can do to 720p60, 1080i29.97 (24p with 3:2 pulldown), 720p25(50), 1080psf25, NTSC and PAL all with relative ease. We do it a lot, but we like the 24p look. A 24p to 25p conversion requires no external hardware, but your audio will be sped and pitched up by 4% along with your video.

Just to be clear, the ioHD does not do standards conversion.

Jeremy


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Jim Wiseman
Re: ioHD Conversions 1080p30 or 1080i29.97
on Feb 26, 2009 at 7:02:24 am

Thanks Jeremy, I'll do some 24p tests tomorrow and see if I can get used to it. I only have one day before I leave. I've been struggling with this one for quite a while. I'm going to have to be a lot more careful with my camera moves.

Jim Wiseman


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Jeremy Garchow
Re: ioHD Conversions 1080p30 or 1080i29.97
on Feb 26, 2009 at 5:25:45 pm

[Jim Wiseman] " I'm going to have to be a lot more careful with my camera moves."

What are you shooting?


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Jim Wiseman
Re: ioHD Conversions 1080p30 or 1080i29.97
on Feb 26, 2009 at 9:41:42 pm

We are in Tahiti for 3 weeks, shooting interviews and landscapes as well as handheld with people doing various activities involving climbing trees for fruit, etc. (a lot of motion) and cooking activities. It involves documenting traditional cultural practices and how they have evolved in the modern world. Interviews and landscapes should be no problem, but I'm a little nervous about the handheld at 24p. Shot some 24p with the DVX-100. Would 60i/24p mixed timeline cause problems? Also, haven't posted 24p timelines before. I'm pretty new to Final Cut.

It's not that I'm inexperienced, I've got 36 years of broadcast experience, including some of the first portable video to be aired in the mid 70's and the first filmstyle video in the mid to late 70's with Hollywood and San Fran film crews. One Pass Video in San Francisco and WTTW PBS in Chicago. I was the only Avid dealer in Hawaii for 5 years, before Final Cut. So much for the resume.

Just want to make sure that I come back with useable stuff that is not going to cause tremendous headaches in post.

Really appreciate your input.

Thanks again.



Jim Wiseman


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Jeremy Garchow
Re: ioHD Conversions 1080p30 or 1080i29.97
on Feb 26, 2009 at 10:29:07 pm

[Jim Wiseman] "but I'm a little nervous about the handheld at 24p."

You shouldn't be. It might take a minute for you personally to get used to it, but you should be just fine.

[Jim Wiseman] " Shot some 24p with the DVX-100. Would 60i/24p mixed timeline cause problems?"

You would need to remove then pulldown and then scale up. A DVCPro HD deck will do this for you in one step (remove pulldown, then up-convert).

[Jim Wiseman] "WTTW PBS in Chicago"

That's where I watched Sesame Street growing up. ;)

[Jim Wiseman] "Also, haven't posted 24p timelines before."

If all of your footage is a derivative of 24p (meaning your SD footage was shot 24p w/pulldown), it's not too much trouble. We shoot almost exclusively 24p and have delivered many projects that had 60i archival or stock footage and everyone has been pleased. You might have to do some conversions.

It's up to you , though, Jim. I am just a guy on the internet. I tend to take my deliverables in to consideration before the shoot and make the decisions from there so in my experience shooting and posting in 24p makes it easier to do standards conversions and I prefer to not work with interlace material. If you don't mind sending out to do standards conversions through a hardware converter and you're more comfortable shooting/posting in 60i, by all means that's what you should do and it is enitrely possible.

Jeremy


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Jim Wiseman
Re: ioHD Conversions 1080p30 or 1080i29.97
on Feb 26, 2009 at 10:44:29 pm

Thanks much, Jeremy.

Jim Wiseman


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Jim Wiseman
Re: ioHD Conversions 1080p30 or 1080i29.97
on Mar 7, 2009 at 12:58:03 am

Jeremy or others,

Have a line on funding for two PAL countries in the Pacific region and Tahiti which I assume is. SECAM. Would this tip the balance to 24p in your mind? Would the speedup to 25p need ioHD or render in FCP? This would b'cst., cable, DVD. Want 1080 minimum.

Thanks!

Jim Wiseman


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Jeremy Garchow
Re: ioHD Conversions 1080p30 or 1080i29.97
on Mar 8, 2009 at 4:15:25 pm

Jim-

Although I don't have much experience with it, but as far as I know in the digital realm secam is no different than PAL. Wheneevr I have had to get secam masters made, I have delivered a PAL digital file.

All the same rules stll apply that we talked about.

Jeremy


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Jim Wiseman
Re: ioHD Conversions 1080p30 or 1080i29.97
on Mar 11, 2009 at 7:51:29 am

Jeremy,

Began shooting with 24p and will stick with it. I am adapting my technique and I am happy with it. One question: when I play back from within FCP from 24p 1080 time line XDCAM HQ codec without ioHD (still at my studio), just from Macbook Pro on its display, I am seeing the video without any pulldown added, am I not? If that is correct, when is pulldown added, and would that further reduce apparent jitter? Or am I offbase here? Would an HDTV or HD professional monitor, say Sony XBR, add furhter smoothing processing as well? Also it is playing back with no dropped frames from FCP here in the field.

Thanks again,

Jim Wiseman


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gary adcock
Re: ioHD Conversions 1080p30 or 1080i29.97
on Mar 11, 2009 at 1:04:24 pm

[Jim Wiseman] "when I play back from within FCP from 24p 1080 time line XDCAM HQ codec without ioHD (still at my studio), just from Macbook Pro on its display, I am seeing the video without any pulldown added, am I not?"

Correct.
there is no pulldown in 1080 24psf, this is a SMPTE standard format
pulldown is only added when needed for the 60i/60p output.

gary adcock
Studio37
HD & Film Consultation
Post and Production Workflows

Inside look at the IoHD
http://library.creativecow.net/articles/adcock_gary/AJAIOHD.php




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Jeremy Garchow
Re: ioHD Conversions 1080p30 or 1080i29.97
on Mar 11, 2009 at 2:40:09 pm

[Jim Wiseman] "Began shooting with 24p and will stick with it. I am adapting my technique and I am happy with it."

Cool. Glad to hear it.

[Jim Wiseman] "One question: when I play back from within FCP from 24p 1080 time line XDCAM HQ codec without ioHD (still at my studio), just from Macbook Pro on its display, I am seeing the video without any pulldown added, am I not?"

You are not, and that is correct. Although what you are looking it as an approximation of what your video really looks like and you won't truly know until you play it out through a capture device and a monitor.

[Jim Wiseman] "If that is correct, when is pulldown added, and would that further reduce apparent jitter?"

Well, here's the rub. When watching back 1080psf23.98 material on most monitors that accept that format, what you are really truly seeing is a 1080 48i signal (aka 1080psf23.98). So, your monitor is refreshing 48 times a second as opposed to what you have been looking at your whole life which is 60 times a second. So the monitor (and I am talking about an external monitor, not your computer display) will tend to look a bit 'flickery', and that's just the monitor without your footage. Putting up a field of white would show this flicker. There are more modern monitors out there that refresh more often (120Hz) and this flicker is reduced when watching on those types of displays. Some people are used to it and can watch it that way, but some people can't. For those that can't, you simply set your FCP video output to 1080i29.97 and FCP will add the proper pulldown on output to get you 29.97 (60Hz) and the monitor will stop that flicker. It might also help smooth out some of the jitter of the motion of your footage as well, if you still aren't used to it.

Make sense?

Jeremy


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Jim Wiseman
Re: ioHD Conversions 1080p30 or 1080i29.97
on Mar 12, 2009 at 7:32:13 am

Yes, it does Thanks much for all of your help on this, Jeremy, Gary, and all.

Jim Wiseman


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Jim Wiseman
Re: ioHD Conversions 1080p30 or 1080i29.97
on Mar 25, 2009 at 5:38:26 pm

Back home and playing back the footage directly from the EX1 component out to Sony XBR37 component in. Very happy with the footage, and glad I shot the 24p. I suspect pulldown or some sort of processing is being done, although I have all of the available "processing" settings on the XBR off, as the footage seems much smoother than on the Macbook Pro in the field. Is pulldown being added anywhere?

Thanks again

Jim Wiseman


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Jeremy Garchow
Re: ioHD Conversions 1080p30 or 1080i29.97
on Mar 25, 2009 at 5:45:42 pm

Glad you found success.

[Jim Wiseman] "I suspect pulldown or some sort of processing is being done, although I have all of the available "processing" settings on the XBR off, as the footage seems much smoother than on the Macbook Pro in the field. Is pulldown being added anywhere?"

I am simply not sure, but I know on some 1080 cameras that shoot 23.98 natively, pulldown is automatically added to the outputs. Hook your camera up to your ioHD and see what it says for the input format. It will either be 1080sf23.98 or 1080i29.97. After that point, we will take the next step. From memory, I belive the EX1 adds pulldown.

Jeremy


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