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Prores test, what a suprise!Posted by AClaude
But unfortunately not a good one.
Today I ran some tests capturing with a sony ex1 straight from the SDI into a Decklink SDI card. The goal of the tests was to compare prores against cineform and the standard xdcam footage. But it turned out to be a hard test because my computer was dropping frames like crazy while trying to capture prores HQ with the decklink from the SDI. I tried everything but couldn't get FCP to capture without dropping frames. I was disappointed because prores is supposedly made to be used on laptops. I couldn't understand why my machine which more than exceeds the minimum requirements would drop frames. I tried with several different drives and even bought a new one and it still did not work. Didn't try a raid but my understanding is that prores doesn't need a raid. Decklink drivers were installed properly etc. but nothing I could do helped. I would capture a few seconds and then stop because of dropped frames. Then for my total surprise, I tried capturing cineform under windows with the very same decklink card and it worked like a charm. i thought cineform was a harder codec to capture to and much more hardware intensive but apparently not. Anybody would have any ideas why my system could be dropping frames while capturing to prores? Thanks.
Aroo? Claude, you seem to have gotten yourself mired in a nasty swamp of bad info somewhere along the line. ProRes was most definitely not "made to be used on laptops." It's a high-data-rate finishing codec.
Sigh. Your understanding is way, way wrong. When you're capturing a live feed, you always need a RAID. Always, end of story.
Well, for starters it sounds like you were trying to capture on a laptop with no framestore. That's something that stands out to me. Seriously, man, where are you getting your information on this stuff? ProRes is noisy, it's made for laptops, it's okay to live-didge to a single drive ? somebody's filled your head full of stuff that's not merely wrong, it's all the exact opposite of the truth.
Jeff Harrell Wrote:
------------------------------------------------------- > I was disappointed because prores is supposedly > made to be used on laptops. > > Aroo? Claude, you seem to have gotten yourself > mired in a nasty swamp of bad info somewhere along > the line. ProRes was most definitely not "made to > be used on laptops." It's a high-data-rate > finishing codec. > > Didn't try a raid but my understanding is that > prores doesn't need a raid. > > Sigh. Your understanding is way, way wrong. When > you're capturing a live feed, you always need a > RAID. Always, end of story. > > Anybody would have any ideas why my system could > be dropping frames while capturing to prores? > > Well, for starters it sounds like you were trying > to capture on a laptop with no framestore. That's > something that stands out to me. > > Seriously, man, where are you getting your > information on this stuff? ProRes is noisy, it's > made for laptops, it's okay to live-didge to a > single drive ? somebody's filled your head full of > stuff that's not merely wrong, it's all the exact > opposite of the truth. Jeff, I did not try to capture to a laptop. As I mentioned I tried capturing it using a Blackmagic Decklink SDI and you obviously can not install such a card in a macbook pro. It was a macpro. About prores being made to use in latops, I was speaking figuratively, meaning prores is supposed to be an easy codec to work with, as far as I'm concerned. About it not needing a raid, well, this was the info that the Blackmagic reseller passed to us when we got the card. Uncompressed we would need a raid, prores not. But the strange thing is how come I did not need a raid for capturing Cineform? Isn't Cineform a much "heavier" codec to encode to? I also captured uncompressed 8 bit 4:2:2 without a raid today Concerning prores being noisy, I found more reports of this and somebody even chimed in on the old thread reporting he has found it too. May be only in very special situations but apparently people are not imagining it. But I decided to see for myself and test it . Pity the prores side didn't work, only the cineform.
Jeff, just googled the prores raid need thing and found this in the first hit:
"You do *NOT* need a raid to capture Pro-Res HQ to a 7200 3gbs internal SATA drive. I do this all the time and a user here, shot an entire feature film, capturing Pro-Res HQ without a RAID - all to an internal drive in his Mac Pro. The only requisite is a capture card that supports Pro-Res acceleration. There are two to choose from: the Blackmagic Decklink and the other is the AJA Kona / IoHD. Sorry, but I wanted to clarify that." This is exactly the info we got from the Blackmagic reseller.
Sorry about the laptop confusion. I'm high on cold medicine today, so when you said you thought such-n-such was supported on a laptop, I thought you meant that you were using it on a laptop.
As for the rest of this stuff: whatever. No offense, but I kind of find myself wondering why you came to a forum seeking advice only to argue with that advice every step of the way. You're shooting greenscreen on an EX1, man. A noisy-as-hell half-inch sensor with cheap glass. Record it however you want. Seriously. It's not going to matter.
Jeff, I'm not seeking advice only to argue with that advice every step of the way. I respect people's opinions, but in the end this is a forum to debate topics related to FCP and that's what I'm doing.
Jeff Harrell Wrote: ------------------------------------------------------- > You're shooting greenscreen on an EX1, man. A > noisy-as-hell half-inch sensor with cheap glass. > Record it however you want. Seriously. It's not > going to matter. You just said I have gotten myself mired in a nasty swamp of bad info somewhere along the line. Judging by the comment above I guess you may have too. Have you used the EX1 and EX3 cameras? A F23 or a Viper it's obviously not but it's a great camera. Noisy it isn't, it's not only the cleanest camera in it's price range but the blue channel is less noise than the RED one blue channel. The fact it is half-inch says nothing, a F23 is 2/3" and I take it any day of the week over a RED. Cheap glass? Well, have you seen how good it intercuts with RED material? Check the comparisons online. There must be a good reason why RED has deleted EX1 posts over Reduser (along with Canon 5D ones). Then to say capturing 10 bit 4.2:2 over 8 bit 4:2:0 isn't going to matter just makes no sense whatsoever and shows me you can only be angry. Sorry if I hurt your feelings with my questioning of prores. I'm sure prores is a great codec but it doesn't mean it can't be questioned. Even sheer, cineform and red raw have flaws and those have a better rep than prores. I was just trying to findout if prores was for me since it comes free with FCP and works easily inside FCP. Didn't mean to step on anybody toes.
What is your Mac that more than exceeds the spec? For instant answers to more than one hundred common FCP questions, check out the LAFCPUG FAQ Wiki here : [www.lafcpug.org]
Something is weird. I've gone to tape off a FW800 drive on RAID 1 on half hour eps. You don't need a RAID for ProRes, but you need a fast enough hard drive. We need details here.
What model/clock speed/no of processors and RAM do you have in your Mac, what OS/QT/FCP version are you running. And what kind of framestore, what is the average throughput on your drive array. What are your capture settings? Great if you can grab a screen shot of your capture settings and post it. You're mistaken if you think ProRes was designed for a laptop. Without a hardware ProRes compressor, you need an Intel Mac with at least 4 cores running at a minimum of 2.4Ghz clock speed. No Mac laptops have 4 cores yet. www.strypesinpost.com
AClaude Wrote:
------------------------------------------------------- > "You do *NOT* need a raid to capture Pro-Res HQ to > a 7200 3gbs internal SATA drive. I do this all the > time and a user here, shot an entire feature film, > capturing Pro-Res HQ without a RAID - all to an > internal drive in his Mac Pro. > > The only requisite is a capture card that supports > Pro-Res acceleration. There are two to choose > from: the Blackmagic Decklink and the other is the > AJA Kona / IoHD. > > Sorry, but I wanted to clarify that." But what frame size and frame rate is he referring to? ProRes HQ at SD resolution is 50 Mb/s but ProRes HQ at 1080p24 is 176 Mb/s - more than 3.5 times more. Check out the data rate charts in the ProRes White Paper, page 20: [images.apple.com] Also bear in mind that not all drives are made equal. The latency of the drive, the size of the cache and how much data is stored on it all play a part in addition to the rotational speed. My software: Pro Maintenance Tools - Tools to keep Final Cut Studio, Final Cut Pro X, Avid Media Composer and Adobe Premiere Pro running smoothly and fix problems when they arise Pro Media Tools - Edit QuickTime chapters and metadata, detect gamma shifts, edit markers, watch renders and more More tools...
If you are using anything less than a Quad G5 or Intel Mac than you cannot guarantee ProRes capture either.
So if you are using a Dual G5 then you system is not fast enough. Let us know what the specs are. So we can help identify where the issue might be. For instant answers to more than one hundred common FCP questions, check out the LAFCPUG FAQ Wiki here : [www.lafcpug.org]
The only requisite is a capture card that supports Pro-Res acceleration. There are two to choose from: the Blackmagic Decklink and the other is the AJA Kona / IoHD.
Nope, there is no such requisite. What's more, the Decklink has no more (and no less) "Pro-Res acceleration" than any other I/O hardware on the market AClaude, perhaps you may have misunderstood your Blackmagic reseller on this point. It is only the AJA IoHD which contains a hardware based ProRes encoder / decoder chip that offers any real hardware based assistance when dealing with ProRes. With the IoHD, ProRes capture is much like DV capture via firewire ie the ProRes encoding and decoding is happening in the I/O box and the encoded data is being streamed to/from the host computer ... theres no encoding or decoding taking place on the host, only data transfer to/from the I/O device, so it'll work on a laptop that otherwise lacks the quad-core processing power needed for most realtime ProRes HD encoding. Does this answer why your Quad/Octo core MacPro failed to capture ProRes when it handled Cineform capture without issue? No. But hopefully some helpful info somewhere in there nonetheless. Best Andy
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