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Canon XL and GL Series DV Camcorders
Canon XL2 / XL1S / XL1 and GL2 / XM2 / GL1 / XM1.


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Old August 26th, 2004, 12:02 AM   #76
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Similar, no...if you put a good HD source next to DVX footage the difference is clear. But you'd be surprised how good DVX progressive footage looks on an HD set. Especially in limited movement, relative close-up type shots...like interviews. It certainly looks as good as the compressed HD streams that typically come over satellite and cable. (lots of movement in high contrast situations will typically start to show some aliasing).

The point being that the DVX's 480p ( and now the xl2's) are somewhat overkill for SD monitors, and there can be a price for that extra resolution. This is why both of these camera's have detail settings that essentially lower the resolution when you get in trouble.

On a side note (actually, the original note)...I just did a camera test with my DVX on a home made moire chart...fun stuff...lots of rainbows...shimmering all over the place...guess we better recall all those panny's. Funny thing happened...I noticed that when I got a certain distance from the chart...I started SEEING moires with my eyes (no camera) --guess this is what the Op-artists were doing... my eyes must be defective too....oh I am tired....see y'all.

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Old August 26th, 2004, 07:45 AM   #77
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Howdy from Texas,

"When new lines meet your eye
from two screens as they ply,
that's a-moire."


Where strange colors now shine,
they weren't there the last time,
that's a-moire."


(apologies to Dino)
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Old August 26th, 2004, 09:04 AM   #78
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I think you need to apologise to us all for that one Chris! ;)

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Old August 26th, 2004, 10:02 AM   #79
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Love it. Can I use it, chris?

I went home last night, and I was trying to explain this moire thing to my girlfriend--she was watching the olympics- 400m hurdles I think- and I looked up at the screen as it was pulsating like electro shock therapy from all the lane lines on the track surface...

I said, "its like that honey"...

she just nodded in that knowing way.......

Barry
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Old August 26th, 2004, 10:13 AM   #80
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hi

hi barry...

nice convincing factors, may be your girlfriend listerns...but no body is ready to nod like a goat....


Well Chris...

Nice poetry.....I think you should publish in the book
After all you are head to all of us...This is kiddish man.

I went to some other sites they were real ,saying that chris is the moire pattern for canon....i never believed....well....this forum is becoming foolish.....I think better to find some other forum...where i can get professional strategies....... I am saying good bye to this forum....

well wish you a good luck ,for every one....


bye bye....


vamshi
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Old August 26th, 2004, 11:43 AM   #81
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Varnshi

your probably gone...so you won't hear this.......feel free to go after me ...but Chris doesn't deserve your comment. There isn't a better person in the web world, and as much as this site has always been a clearing house for Canon oriented information and discussion, I've probably heard chris recommend other cameras from other manufacturers a dozen times on these boards. He's publicly lusted over the 12 bit dsp in the panasonic DVX100, and has offered his web bandwidth to discussions on virtually every topic and manufacturer in this industry. Yes, he is close to canon, and that's why we get such great, detailed information on this site...rather than the rumours, speculation and crap on so many others.

Barry
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Old August 27th, 2004, 04:12 AM   #82
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Vamshi (if you are still here)

I am baffled by your attitude. Barry has provided some excellent information in this thread, which has been very educative for me and probably many others.

As for your attack on Chris and this website, I think it is completely unwarranted. Show me one instance where he has promoted Canon cameras. In fact, you will find a lot of speculative (and apparently largely unwarranted) criticism of the XL2 on this forum. None of this has been censored. Chris will always challenge factual errors, but not opinion. Would you prefer it some other way?

Good luck in finding a better forum for discussion on DV - if you find one, let me know because I haven't been able to. I do, however, suspect that you may find some better poetry sites.

Best wishes
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Old August 27th, 2004, 10:09 AM   #83
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Alright Barry /Duncan.

Good Toast for Chris.. I think you are the good friends for him. I dont even mean to hurt anybody.. This is a forum. ..Everybody comes up with his problems... 2-3instances i observed chris.....answering roughly.. And in dealing with an image problem ..... can you guys answer for this thing...

"When new lines meet your eye
from two screens as they ply,
that's a-moire."

Where strange colors now shine,
they weren't there the last time,
that's a-moire."

its clearly an insult to clive.

I said its nice poetry. Alright, he never comeup with an answer, he took the help of you guys...to support him...this is absolute reality.

Regarding 3 instances... this issue about image problem
the others are regarding the mic problem.. he has given a rough -rough answer.....So also why he never comeup with an answer...why he is not watching this forum......

I dont mean to raise my hand on anyothers....
Weather he supports canon or not is his issue....I also supports canon...,but comparision is my juncture.

Any way guys....cool.......
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Old August 27th, 2004, 10:49 AM   #84
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Gents, if this helps at all:

Even when you are shooting film that will ultimately be transferred to video, you have to watch out for potential moire. You don't get the luxury of seeing it on the monitor and deciding what to do with it, you just have to be knowledgeable enough to say "I think we might have a problem with that pinstripe tie" or "the screen in that window may moire down the road". Recent telecine technology has eliminated a lot of this but there are still no-no's out there; as Barry pointed out, you can even get your eyes to moire under the worst of circumstances!

Obviously if one camera exhibits more problems than another, that's reason for concern. Until we actually see side-by-side examples of, say, the DVX100a and the XL2 pointed at the same environment where the problem manifests in one camera vs another (and the detail and other relevant settings are as similar as possible), then I say it's pointless to debate. With all due respect to the intrepids who are posting their initial tests, it seems to be stirring the pot more than anything else. I'm looking forward to a thorough set of tests under multiple shooting situations, from charts to real-life high-contrast scenes to lowlight scenes, with both cameras. I'd be happy to do them myself, if Canon sent me a camera.
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Old August 27th, 2004, 11:13 AM   #85
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Oooh... Nice cast there Charles, Hope you get bite!
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Old August 27th, 2004, 11:53 AM   #86
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I'm betting by this time next week Charles. I'm looking forward to a controlled studio test of Xl2 with different lenses and with the P&S...I have the XL1s for comparison as well.
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Old August 28th, 2004, 08:28 PM   #87
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Sorry to bring this up, but I just read this thread. It's very strange to me that no one here recognized this right away by looking at the two images.

It's not the lens. It's not photoshop resizing. It's not the CCD. It's not related to anything at all, except deinterlacing.

Take the better of the two images, go to photoshop, go to Filters > Video > Deinterlace (default settings). You'll get the same moire patterns as with the other image.

The problem is that the second "progressive" image got deinterlaced somehow (progressive should never be deinterlaced by definition) because of inappropriate settings within the software/camera etc.

As for this effect being visible in the viewfinder -- could be camera settings, or perhaps the camera doesn't have a progressive path to the viewfinder. The output would be progressive regardless, and should be free of any artifacts as such.

I don't personally use these cameras, so I can't comment on any specific options they may have for this. But this is a very simple problem nonetheless.

Edit:
About the viewfinder moire -- another big factor would be simple downscaling of a 960 x 480 image > viewfinder pixel count. That would just result in simple aliasing then, which in turn would create moire patterns on fine lines, grids etc. The solution then would be to get a good CRT viewfinder.

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Old August 28th, 2004, 09:19 PM   #88
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Clive says the artifacts are present on a monitor when the video is played back. This would eliminate PS and de-interlacing as as source of the artifacts.
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Old August 28th, 2004, 10:15 PM   #89
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Sorry, but it's most certainly deinterlacing. There is no doubt.

There is no other way a progressive image would lose half of it's vertical resolution in this exact manner. Look at anything diagonal in the picture. You can see very obvious staircasing and pixelation -- that's a result of very basic deinterlacing.

Monitor - what kind of monitor? If it's a video monitor then it will most likely be interlaced, (unless it specifically supports progressive) which could easily create moire when progressive footage is played back on it. You have to use progressive video monitors to play progressive footage. If your final output is intended to be interlaced, then you should shoot in interlaced mode to begin with...

If progressive footage shows moire effects on a computer monitor, then I would say it's most likely an automatic deinterlace setting that was left on somewhere. The software we use here is different, but it allows specifying whether the source has fields or not, and the program will deinterlace the video automatically while you edit it, but keep it interlaced on export. I'm guessing basic video editing programs assume DV footage to be interlaced by default (which makes sense).

To be honest, the reason could be anything. But I can say from my very substantial experience with doing video transfers that the moire artifacts that Clive showed are definitely as a result of deinterlacing. That's the one statement behind which I stand 100%. The rest is in the details...

For further proof, please try what I suggested. Save the better progressive image provided by Clive (without artifacts) and open it with photoshop and run Filter > Video > Deinterlace. You'll see that it's totally identical to the image with moire, down to the finest details.

I knew what the problem was the second I saw the bad image, I've been deinterlacing videos for a long time. Sorry if I sound too pushy, but this is an area that I have far too much experience in. :)
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Old August 28th, 2004, 11:07 PM   #90
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Nick, I'm not really disagreeing, but Clive has quit posting again (I think he wants us all to take out a subscription) and without access to the native DV files it is impossible to tell the cause with 100% certainty. I agree with what your saying and I was headed to the same conclusion in my first post. However, his insistence on seeing it on the monitor leaves many gaps in trying to determine it's actual cause.
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