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Reflecmedia are the people who do that: http://www.reflecmedia.com/
If you really really wanted you could do the colourspace conversion with CC nodes too – it’s linear, so each of Y, U and V are just weighted sums of R, G and B. If you really wanted to do this you could get the coefficients from Charles Poynton’s excellent article about the conversion: http://images.autodesk.com/adsk/files/Merging_RGB_and_422.pdf
You could probably do the RGB to YUV using the keyer in YUV mode outputting mattes with 0 tolerance and max softness but this is just getting silly 🙂
paul_round wrote:My worry about getting the Tezro would be future support, as I believe SGI stopped making it at the end of last year due to the Kyoto agreement (same deal as CRT monitors)Where did you hear that? I don’t think that’s the case… SGI are very good about issuing end-of-production notices, usually at least six months in advance, and there’s nothing on their support site to say that. And since their machines from more than ten years ago are still in active support mode I should think there’s life in the old Tezro yet…
Although there is a possibility that the entire company could go bankrupt fairly soon 🙂
Seperate and Combine are in Batch in the newer versions. I suppose that spark gives you Y on R, U on G and V on B but I can’t remember off the top of me head. Well if it was obvious in the keyer which one was wrong I guess it should be obvious if you take them all into Action 🙂 Do let us know how it all pans out.
Always wondered how people went straight into Inferno from a greenscreen stage… so… with stupid long wires, then? 🙂 If one cable was slightly different or older or broken or something it could affect the transmission speed down that wire and so do this.
Anyway you don’t need any fancypants sparks – two of the example sparks that come with Inferno do RGB -> YUV and the reverse. You should find them in /usr/discreet/inferno_4.7/sparks or similar. Use sparkYUV on your footage, then Seperate, shift the blue or green (could be either), Recombine, and put the result through sparkRGB.
Sadly the two sparks don’t work in Batch, I could fix that but it’s midnight here. Good luck 🙂 I guess you could take both chroma channels into Action to line them up, if you’ve got something sharp in frame, maybe if you can see the edge of active picture on the delayed one?
Oooh dear… could be an analogue fault. This might sound silly or obvious but did you use radically different lengths of cable for the U and V connections? You could try converting back to seperate Y, U and V channels, and see if shifting U or V left a bit helps. Can you still see the halo if you view the footage in black and white?
How about taking the matte you pulled from the greenscreen, shrinking it ever so slightly, then using it to displace each layer in Z? If you shrink it slightly so you’re displacing less area than is there, you should get some kind of “sides” to the shape. You’ll probably want to turn the Resolution right down to 1 to get it accurate.
Or you could do find edges on the matte then use that to displace in Z a copy of each layer, which might just give you the “sides” on their own. Again probably with Resolution turned down, be prepared for slowness 🙂
iraflowers wrote:What happens is the CCD’s will be set to a progessive mode and the signal is recorded interlaced to miniDV. This is important to understand. I would not use the progessive mode to shoot greenscreen and elements. The end results can be less satisfactory.How do you mean? DV is not an inherently interlaced format – it dynamically chooses whether to compress fields individually or together on a frame-by-frame basis. Even if it did choose wrongly and compress fields one by one, it’s not a problem – all the progressive information can be retrieved simply by interlacing the fields back into one image. This is even less of a problem when working with computers, which play video like that anyway.
Or do you simply mean that it records 25p rather than 50p? That’s certainly true.
If the comp is going to have a still-ish background and a film-ish look I’d shoot progressive – you’d likely have to throw away one field to remove the interlace artifacts otherwise.
xenio wrote:I don’t know if is it better to remove blue screen from a blurred movements on the frame (progressive) or remove blue screen from a line shifted frame (interlaced)By the way, you shouldn’t ever suffer trying to key an interlaced frame – it’s horrid! Seperating the fields out, keying and comping then reinterlacing back to frames is much less painful 🙂
While you can stuff pretty much any kind of data imaginable into to Cineon and DPX files, it might well be that AE won’t write alpha channels into them, and so just wrote the fill without the matte. And since Photoshop will rasterise its type into a blocky fill layer plus an alpha channel with the softer-edged matte, if you don’t premultiply as part of the output process the fill Cineon files on their own will look nasty.
I guess it could also be that AE *is* writing fill and seperate matte into the files but whatever you’re viewing them with is not reading the alpha channel?
Host.ini should be inside your Combustion program folder – try searching for it with Windows’ Find thingy. Renaming or deleting it makes Combustion generate a new one with all default settings, and can fix random weirdnesses like this… sometimes 🙂
If it’s any consolation, you’re not alone 🙂 This happened to me with the v4 demo on my laptop, and I never found a fix. Didn’t have time to dig into it with a debugger or anything.
Every other machine I’ve used has been fine.
You shouldn’t see banding unless you majorly CC it afterwards or something. Or you’re doing something REALLY soft and fluffy 🙂
In which case Speedsix AntiBand might be your friend, or a blur if you don’t have that, or if you have time you could make a matte of the edges with Find Edges and some blurring or eroding, invert it and use it with a compound blur to smooth the non-edgy bits?
Normally you buy FC stuff as a system because you need it to Just Work, but if you really want you can get little backplanes or T-cards and build arrays – I got boards, wires and disks from here: http://ckcomputersystems.com/ckcs/catalog/default.php?cPath=21 and crammed the resulting block into an old Kingston SCSI enclosure with the insides ripped out. Mine is _really_ homebrew though, I mean the air holes are sealed with gaffer tape and the fans are held in with bluetack 🙂
This may be obvious, but did you try the Blending parameters in the Master Keyer? With AutoCC on, choose Blending from the Sample popup, then tap anywhere on the image, adjust Luma and Edge Size, maybe the edge colour trackball too… this problem is what they’re designed to fix.
If not, you could create an edge matte by subtracting a shrunk version from the original matte, and use that to do some more technical CC work…