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Old February 3rd, 2002, 03:28 PM   #1
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XL-1 frame mode vs external frame modes

I have read that the XL-1 uses a special trick to shoot in frame mode by offsetting the green sensor by one scan line.
http://www.dvfilm.com offers a special programm called DVFilm Maker which seems to be specialized in de-interlacing.
Has someone else tried this programm or knows if there are really differences between different de-interlacing methods ?
If this one really makes the movie look more movie like than any other de-interlacing method then i think about 100$ is a quit good deal.
I havn't compared the XL-1 frame mode with the dvfilm frame mode yet but i give you 2 links to 2 pictures i've extracted from a test shot.
The first one is the standart interlaced mode and the second one is de-interlaced with the test version of dvfilm (both about 1.2MB).

http://home.t-online.de/home/ETewes/interlaced.bmp
http://home.t-online.de/home/ETewes/deinterlaced.bmp

Perhaps here is someone who is able to make a professional test about different de-interlacing methods - it would be very interesting to see the results
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Old February 3rd, 2002, 04:19 PM   #2
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Not too bad though the XL1 frame mode looks much smoother. On your example I can still see that it has been deinterlaced by looking at the thin branches on the tree. Personally I hate deinterlacing. The XL1 doesn't "deinterlace".

Anyway, if you want a REAL test for the program, capture a very fast moving scene. A scene where the two interlaced fields would be almost completely different from eachother. Then run it through the program.
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Old February 3rd, 2002, 04:26 PM   #3
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Oh yes, here is an example (also in BMP format) of an unretouched frame that shows plenty of motion that was shot using the XL1's frame mode. Look... completely smooth, next to no jaggies!

http://207.168.10.78/frame.bmp
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Old February 3rd, 2002, 06:04 PM   #4
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Hmmmm...i will do a test in the next days. Fast moving action with XL-1 frame, interlaced and de-interlaced by film maker.
I tried a de-interlacing with Premiere 6 but it doesnt worked, perhaps i've done something wrong but everytime i get an interlaced one.
But there is still an open question. On 2 or 3 pages (companies who do DV to film transfer) i read that the resolution is reduced by the method and when you want to transfer something from DV to 16/35mm they ask for material that is de-interlaced in a separate step, not in shot by the XL-1.
Perhaps i missunderstood something but who is the one who tells the truth - or depends it on what you want to do with your XL-1 (birthday party video or feature for later film transfer) ?
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Old February 4th, 2002, 02:00 AM   #5
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The resolution is indeed reduced a bit, the color resolution
that is. Because the XL1 and the S model don't have true
progressive chips it does some tricks to get the frame mode.
I think only the green color is fully sampled, the red and blue
are only sampled the other line or something. Someone else
know how this exactly works?
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Old February 4th, 2002, 10:13 AM   #6
 
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according to Joe bogasz(sp), the Canon rep, the frame movie mode captures ONE complete frame per 30 secs. The camera then divides that frame into two split frames for every 60 secs, so that DV software sees what it thinks is interlaced video. The point is that the entire frame is captured in one instant, thereby avoiding the temporal artifacts you see in the normal interlaced mode. Accordingly, if you try to de-interlace footage captured in frame mode, you'll cause artifacts to appear that weren't in the original footage...DON'T DEINTERLACE FRAME MODE VIDEO. Another implication to this is that you are capturing at 30fps, very close to film rate. This causes a slight flicker from frame to frame in fast pans...just like film.

On the subject of de-interlacing software for NTSC mode, there are many algorithms around, the best of which seem to be area based de-interlacers. A good area based de-interlacer is available from Donal Graft's website. It's designed to be used with AVISYNTH or VirtualDub. It works well, I recommend it.
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Old February 4th, 2002, 10:21 AM   #7
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I don't think that this is correct bill... As far as I know all
video is in frames... Both fields (when doing interlaced capture)
are put in one frame, thats why we see those lines on our
computers. I definitely know that it doesn't do full resolution
color in frame mode.. Ofcourse your picture format stays
the same, but the color resolution drops...
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Old February 4th, 2002, 10:42 AM   #8
 
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Just going by the info in Chris' site at: http://www.dvinfo.net/canon/audio/framemovie.rm
and my own experience. I have not experienced any combing artifacts while in frame mode.

One more sidebar here.....I was wondering how the XL1 can capture at a shutter speed slower than the frame rate of 30fps. Apparently, the computer in the XL1 has a buffer where it stores the frame data...interesting, eh? So it stores data at 1/30 sec and creates virtual shutter speeds below the min rate.
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Old May 8th, 2003, 10:39 AM   #9
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Yeah Carter. The links you provided don't work. Have you by any chance copies?
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Old May 8th, 2003, 10:50 AM   #10
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that thread is quite old :-P
no, i just looked if i have those 2 pics on a cd - i havn't :-(
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Old May 8th, 2003, 11:59 AM   #11
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Thanks anyway
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Old May 8th, 2003, 12:15 PM   #12
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I have seen somewhere, a clip that was done using this software. Now if I can oly remember...
Maybe there are other sites. Anybody knows?
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Old May 9th, 2003, 08:17 AM   #13
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"Both fields (when doing interlaced capture)
are put in one frame, thats why we see those lines on our
computers"
Rob, you're right about this: you only see those lines on the computer monitor. Because the PC monitor is NOT interlaced, like the TV. Both frames are put in one frame only when you watch it on the PC monitor. But the two fields ARE sperated on the tape and seen separated on a TV set.
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Old May 22nd, 2003, 02:09 AM   #14
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Hi Folks!

If you need more information about interlace/deinterlace and the different methods of deinterlacing, have a look at http://www.100fps.com
You'll find a great description

Sebastian
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Old May 22nd, 2003, 08:58 AM   #15
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Also, many NLEs will detect XL1 frame mode and allow you to edit in 30p. For example, with Vegas, you can set your project format to progressive and drop XL1 frame mode footage on the timeline. All FX, transitions, titles, and motion will be calculated at 30p instead of 60i. When you render, create a 30p template instead of using the 60i default.
///d@
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