Bj Ahlen
Forum Replies Created
-
[Bill Portune] “I was able to use a crop of 1 at the bottom of each shot which solved the problem. “
Field order problem?
I take it you imported the footage as interlaced and then tried to deinterlace it?
-
I would take a chance on this upgrade.
It looks legit, and you may be able to get it at a low price if you are able to “snipe” it.
To snipe, you decide beforehand what is the highest price you want to pay, then you make sure you are absolutely positively ready one minute before the expiration of the auction. Submit your bid but don’t confirm it until about 30 seconds before the end, so that the weak-kneed don’t have time to outbid you.
Let’s say the auction is at $99.50 at one minute before ending. You decide that you’ll pay up to $200 for this, so you enter a max bid of $201.12 (because newbies like to bid round numbers) and confirm your bid. If the #2 bidder has a max. bid of $149.00 say, they will get a message saying that they have been outbid, but at that point it will be too late, and you get it for $150.00 (just the minimum step above).
If you had put in your max. bid a day before or an hour before, the losing bidders often become sore losers, and they tend to then bid more than they really wanted to spend or they could afford, just for the sake of winning.
So protect their wallets by “sniping,” it makes good business sense for you and you’ll have done your good deed for the day!
:O)
B.J. Ahlen
(a former live auctioneer) -
I used an AJA IO to capture SD-SDI this way into FCP on an MBP for a long time, works great with no hassle.
-
Short answer: Yes.
Long answer: You should test a short snippet with representative samples of your 25p and 50i footage and encode this to 24P and 60i for DVD, to see which you like the best.
Going from 25p to 24p, I’d conform the footage to 24p and slow down the audio to match. That will give you the best quality with no visual artifacts.
From 50i to 24p, you could deinterlace the 50i to 25p first, then do the conforming above.
-
NTSC SD is always interlaced.
The digital successor standard, ATSC, includes a 480P format.
SD DVDs can also use 24P (23.98 really) progressive SD footage for efficiency, because DVD players can convert this to 29.97 interlaced frames per second using pulldown if necessary (for viewers who use ye olde interlaced-only TVs).
Today it is quite difficult to find any TVs with interlaced displays, as CRT factories have closed and newer display technologies are inherently progressive.
Still, we may not get rid of the interlaced video formats until the last TV engineer has been put six feet under (with a garland of garlic around his neck and a stake through his heart).
I hope no one gets the idea that I don’t like interlaced :O).
-
I’m using a Mac Pro next to an HP xw8600 Windows workstation, by necessity for now.
The HP workstations can actually save you trouble over consumer PCs, and I think their xw4600 models start at something like $600-$700 (in the U.S.).
Configure it with the cheapest hard drive they offer, then image this to a $70 or so WD three-platter 640GB drive for your system drive. Add a few more for media. This drive measures about 100 MB/s read and write in the Decklink speed test, which is as fast as the older generation expensive Velociraptors.
I have also had good experience with HP support, not to mention what you get when you buy from a pro dealer. Those guys are as hungry as everyone else, so a little bit of price discussion won’t hurt anyone.
HP workstations are well built (including tool-less drive replacement), well configured, and there is some good thinking behind each part.
-
[Nicholas Bierzonski] “I am still blown away by the editing Mr. Hitchcock did with that shower scene. It still holds up today even though it was cut old school with a razor blade! I humbly bow before his mastery and prowess. This scene gives us all something to strive for and measure our own skills against. “
Yep. Especially since Hitchcock “did the cuts in pre-production.”
He was mortally afraid that “the suits” would screw up his artistry, so he planned his shooting so carefully that, after each scene was shot, there was no footage available to reasonably cut it in any other way than he had planned it.
This is something to remember for filmmakers who are concerned about their productions becoming “lamp posts” for producers eager to mark their territory.
-
Why $600?
The most common MC software upgrade is less than $500 direct from Avid, and can be had for quite a bit less from some of their online resellers.
That’s for a box upgrade with not just MC3 (which is great), but also all the 3rd party apps that have been quite significantly enhanced, not just BCC5 but also Sonic DVDit Pro HD for example.
-
[Jan Crittenden Livingston] “If the 8 bit signal starts at 994 mbs and one algoritm delivers individual frames and a payload of 100mbs, and the other offers Groups of pictures so that your resolution is not frame independent and a payload of 35mbs, the 35mbs has more compression. You can put whatever marketing spin to this you want, the 35mbs has more compression. It is more efficient, sure, but maybe that shouldn’t be the priority when capturing the master footage.”
When you are bandwidth-constricted, efficiency is the #1 concern.
Why? Because whatever picture information cannot be reduced losslessly through efficiency, has to be compressed using DCT (Discrete Cosine Transform) and other lossy techniques that impact the picture quality.
In Long GOP formats (such as XDCAM EX), most of the stored data is frame differences.
In Intra-Frame codec formats (such as DVCPRO-HD), all of the stored data is separate frames, each of which in the case of DVCPRO-HD has to be compressed with four parallel codecs ending up with a DCT compression ratio of approximately 6.7:1.
The Long GOP format has much more space left over for picture information, so it needs much less image compression after the [lossless] data reduction of the Long GOP storage scheme.
In the case of XDCAM EX, the extra efficiency is used to a) reduce the bit rate from 100Mb/s to 35 Mb/s VBR (Variable Bit Rate), and b) store the additional resolution (1920×1080 vs. 1280×1080 for DVCPRO-HD), and c) reduce the image compression to get a sharper and more pleasant picture when there is less movement, which also happens to be when it is most needed.
The flip side is that it Long GOP is very resource intensive when editing, so it takes an up-to-date computer or rendering to a post codec.
It has been suggested that Long-GOP codecs can’t keep up with fast movement. This has been observed only in rare cases in HDV footage (less advanced codec, inexpensive DSPs), and not even in difficult circumstances (such as a tree with thousands of leaves blowing in the wind) with XDCAM.
[Jan Crittenden Livingston] “[B.J. Ahlen] “DVCPRO-HD is also limited in resolution. It maxes out at 1280×1080, while XDCAM EX as noted is a full raster codec at 1920×1080.”
You are also mistaken here. These numbers are based on the pre-filter intelligently applied to the signal prior to compression. If you look at the XDCAM HD signal coming from the 355 Sony camera the recorded footprint is 1440 X 1080. This also due to the pre-filter. Manufacturers apply this pre-filter to get rid of frequencies and details that are problematic for the algorithm. With almost 40% more signal, 1920 X 1080 XDCAM EX, vs the XDCAM HD 1440 X 1080, it still has to fit in a 35mbs payload. Numbers are easy to understand but if you don’t understand why they are what they are it can lead to the misinterpretation of the number.”
Jan, I’m confused about what you are trying to say here.
1. I said, “DVCPRO-HD…maxes out at 1280×1080, while XDCAM EX […] is a full raster codec at 1920×1080,” to which you respond “You are […] mistaken here” and then you refer to “1920 X 1080 XDCAM EX.”
So it would seem that I was not mistaken, unless I didn’t understand what you were trying to say.
2. You said, “In the Sony F355, […] the recorded footprint is 1440 X 1080 […] due to the pre-filter.” What are you referring to? The F355 has 1440×1080 CCDs, and that is what it records to blue laser disc in the camera, with wide pixels (PAR) of course. So it’s the source CCDs and a desire to keep the 1440×1080 format that determines this, not pre-filtering.
The XDCAM EX on the other hand records a 1920×1080 signal from 1920×1080 CCDs in HQ mode. The pre-filtering has no bearing on this.
Panasonic appears to prefer using internal uprezzing in most of its affordable models, which can necessitate pre-filtering before compression, while Sony cameras generally record in native resolution.
You were comparing the XDCAM HD vs. the XDCAM EX. It wasn’t clear to me exactly why, other than your point that higher resolution takes up more room.
Was your point that DVCPRO-HD would have much better picture quality in each frame because its resolution is so much lower?
Or was it just that the EX video couldn’t look nearly as good as the XDCAM HD’s because it had to fit 40% more pixels into the same 35 Mb/s bandwidth ?
Well, you have people like Jody Eldred saying that his XDCAM EX footage intercut perfectly with his F900 footage (he owns both cameras).
And finally, let me be clear that I have no connection with either Sony or Panasonic other than as a satisfied customer of high end pro gear from both.
-
[walter biscardi] “I can speak from experience that the DVCPro HD codec is fantastic for post. We’ve been cutting with that codec for three years now and have delivered about 80 HD episodes to networks so far.”
Yes, of course it works good for post. It’s been used for many years and it is rock solid within its parameters.
Is it fantastic for post? That’s a value judgment. If you have to deliver full raster 1920×1080, I’d say not, because it doesn’t support full HD, so you have to uprezz as a final stage before delivery.
If you had to do significant compositing and grading, the end result would have been better if you had switched immediately after acquisition to a full raster post codec such as ProRes HQ, Avid DNxHD, or even Sheer.
720P has been a delivery format for quite some time now, but I trust you can see where things are going. If you are going to sell your productions again in a few years time, it is not likely that you will find acceptance for anything less than 1920×1080, unless it is “must-have footage” that will be run through a Teranex before broadcast.
Even consumers now are calling for 1920×1080 “Full HD” (a Sony campaign term I believe), and European broadcasters have been holding out as long as they could for 1920x1080P.
[walter biscardi] “I have no idea how XDCAM holds up in Post as we’ve never had to use that format.”
Blech. As I said, you can do simple cuts and basic stuff without much worry, but why suffer? Just use a purpose-designed post codec.