XL1S imaging problem/question at DVinfo.net
DV Info Net

Go Back   DV Info Net > Canon EOS / MXF / AVCHD / HDV / DV Camera Systems > Canon HDV and DV Camera Systems > Canon XL and GL Series DV Camcorders > Canon XL1S / XL1 Watchdog

Canon XL1S / XL1 Watchdog
Can't find it on the XL1 Watchdog site? Discuss it here.

Reply
 
Thread Tools Search this Thread
Old April 23rd, 2002, 11:59 PM   #1
Regular Crew
 
Join Date: Apr 2002
Location: Redwood City, CA
Posts: 40
XL1S imaging problem/question

Hi folks,

I have a brand-new XL1S, with a vexing imaging problem. I wonder if anyone with the same camera has the same, or similar problem, and if you've found a fix (other than, of course, sending it back to Canon)??

When viewing on a PC, e.g. in Premiere, there's a horizontal black bar at the bottom of the picture, 4 pixels tall. The viewing window is 720x480, so the XL1S is cutting off lines 477,478, 479 and 480. The window ISN'T 780x486, so this isn't a D1 versus DV issue (I think).

Above the black line is a 1 pixel bright bar, i.e. it brightens the bottom 1 pixel of the picture. There's also a light colored vertical line, 1 pixel wide, at the left of the picture. These problems appear
on two completely different systems that I use for capture: IBM
ThinkPad A30p with built-in 1394 interface, and a desktop P4 PC with a Pinnacle Studio DV card. All apps show the same effect: Windows Movie Maker, Premiere 6.0, Pinnacle Studio 7.

A tape recorded on my XL1S, but played back on a consumer Sony TRV10 camera shows the same problem, although footage recorded on the same tape on the TRV10 is perfect. A tape recorded on the TRV10 captures
perfectly, i.e. the whole 720x480, when played in the XL1S. This leads to the conclusion that it's something in the XL1s' imaging path or the recorder that's at fault.

Windows Movie Maker allows LIVE capture through the 1394 port. That clinched it: with NO tape in the XL1S, to ensure that I'm really seeing the live feed, the black bar (and the bright bars) are there in the live Movie Maker preview. Fiddling with image stab, iris, clearscan, AE adjust and shutter speed has no effect. Changing lenses to the wide angle zoom, and a couple of EF lenses with the EF adapter, has no effect.

So, my guess is that the CCD array is misaligned: it's about 5 pixels high and one pixel to the right of where it should be.

These imaging faults are outside the TV Safe area. But, as I watch videos on my PC, that's no consolation. Even for viewing on a TV, these faults are a pain when doing, for example, PIP or many transitions/wipes. It's possible to crop them out, but it's a lot of work.

Thanks in advance! Alex Osadzinski.
AlexOsadzinski is offline   Reply With Quote
Old April 24th, 2002, 03:19 AM   #2
Wrangler
 
Join Date: Feb 2002
Location: Cleveland, Ohio
Posts: 1,933
Alex,

This is a serious issue that has appeared on many XL1Ss (though I never had this problem with my old XL1). We've already discussed this here (http://www.dvinfo.net/conf/showthread.php?s=&threadid=1482).

Please call Canon Customer Service at 1-800-828-4040 and complain. Loudly. Don't let them convince you that this is not really a problem because it will never show up on your TV screen. And if you talk to somebody who has never heard of this issue before, ask to talk to Chris.

If you get anywhere with them, post back to this forum. I'd like to see this issue resolved as much as you would, and I will be sending my XL1 back in for repair, because this is NOT a "feature," this is a defect.
__________________
All the best,
Robert K S

Search DVinfo.net for quick answers | The best in the business: DVinfo.net sponsors
Robert Knecht Schmidt is offline   Reply With Quote
Old April 24th, 2002, 09:57 AM   #3
Regular Crew
 
Join Date: Apr 2002
Location: Redwood City, CA
Posts: 40
Thanks, Robert. The thread that you pointed me to somehow managed to omit all of the search terms that I used, so thanks for the pointer.

I called Canon customer service a couple of days ago, and that was not a good use of time: I got the "if it doesn't show on a TV it's not a problem" response. Attempts to discuss PIP, transitions, etc fell on deaf ears. Then, I called the XL1 hotline, and that yielded a completely different response: "it sounds like a fault, take it back to the store for an exchange or send it to us". As I bought the camera locally, at Keeble and Shuchat in Palo Alto, I called them and they said that they'd exchange it this week, as soon as they received a shipment of new cameras. I visited K&S yesterday, and captured video from their display XL1S onto my laptop, and it shows PRECISELY the same fault. In other words, it doesn't seem like a random mispositioning of the CCD array, but a systemic fault.

I'll try a brand new XL1S on Friday at the store and will let you know the results. My expectation is that it'll show the same problem. In browsing this (very useful) board last night, I found some pictures posted of XL1S stills from the NY Natural History Museum. You can't see the black bar, because the background is black, but the single-pixel horizontal and vertical lines are clearly there, too.

So, here's a newbie question (sorry): assuming that we have to live with the black bar, what's the best way to deal with it, especially with respect to compression to MPEG-2 for DVD burning? For picture-in-picture, this is very simple: you just crop the picture-in-the-picture, and all is well. For the main image, to remove artifacts when playing on a PC screen, it's easy to clip or crop the 720x480 image down to 719x475, at least in Premiere. So, the resulting movie is 719x475. When rendered out to a DV AVI file, though, won't Premiere stretch that back out to 720x480, with possible weirdness resulting from the stretch? Or do you think that it's better to retain the original 720x480 size, but put, say, a 5-pixel black border around it? Won't this possibly cause compression problems when rendering to MPEG-2? If it doesn't then it's a clean workaround, because the black border won't show up on a TV, and will disappear into most players' black backgrounds on a PC.

Thanks! Alex.
AlexOsadzinski is offline   Reply With Quote
Old April 24th, 2002, 10:59 AM   #4
 
Join Date: Nov 2001
Location: santa fe, nm
Posts: 3,264
Images: 10
I experience the exact same problem with my XL1s, and have seen it on other brands of vidcams, as well. I have come to just accept it. I use Vegas Video3, which allows me to define the borders of the frame I want to render to 720 x 480. In effect, it's a crop and zoom. Using this, I've been able to remove the black pixels at the bottom of the frame from my rendered video.

I intend to use my XL1s for approx a year then send it to Canon service for a tune up. At that time, I will expect them to re-align the CCD.
Bill Ravens is offline   Reply With Quote
Old April 24th, 2002, 11:16 AM   #5
Regular Crew
 
Join Date: Apr 2002
Location: Redwood City, CA
Posts: 40
Bill,

When you do the crop and zoom, do you get any artifacts as a result? That's a very difficult zoom (about 1%) to pull off without resulting moire patterns?

Thanks, Alex.
AlexOsadzinski is offline   Reply With Quote
Old April 24th, 2002, 01:17 PM   #6
 
Join Date: Nov 2001
Location: santa fe, nm
Posts: 3,264
Images: 10
none...not a one...the effects filter in VV3 handles the crop and zoom as one operation.
Bill Ravens is offline   Reply With Quote
Old April 24th, 2002, 06:12 PM   #7
Wrangler
 
Join Date: Feb 2002
Location: Cleveland, Ohio
Posts: 1,933
Bill, I don't want to doubt you, but I agree with Alex. In a zoom that isn't a perfect multple of 2 along either of the image dimensions, moire is sure to be the result. Even good antialiasing filters (which introduce blurring distortion of their own) don't do a complete job of eliminating moire.

This isn't a challenge, I'm just curious exactly how (or how well) VV3 deals with this problem. So I don't suppose you have some example screen captures handy for posting?
__________________
All the best,
Robert K S

Search DVinfo.net for quick answers | The best in the business: DVinfo.net sponsors
Robert Knecht Schmidt is offline   Reply With Quote
Old April 24th, 2002, 09:15 PM   #8
Obstreperous Rex
 
Join Date: Jan 2001
Location: San Marcos, TX
Posts: 27,366
Images: 513
For Alex, there is no need to test another camera on Friday, I can tell you with all certainty that it will show the exact same properties. At this time Canon USA does not consider it to be a defect, therefore there is no repair or replacement option for it.
__________________
CH

Search DV Info Net | 20 years of DVi | ...Tuesday is Soylent Green Day!
Chris Hurd is offline   Reply With Quote
Old April 25th, 2002, 06:57 AM   #9
 
Join Date: Nov 2001
Location: santa fe, nm
Posts: 3,264
Images: 10
I've posted a composite image with two frame grabs from my video clip. The first image shows a frame with the underscanned pixel rows accross the bottom. The second image shows the cropped and zoomed image of the frame. There is no moire that I can detect. Crop and zoom was performed with the Track Effects module from Vegas Video 3.

The link is:
www.geocities.com/ravens202/MV.jpg
Bill Ravens is offline   Reply With Quote
Old April 25th, 2002, 11:14 AM   #10
Regular Crew
 
Join Date: Apr 2002
Location: Redwood City, CA
Posts: 40
Indeed, the crop and zoom looks pretty good. It looks as if you cropped off more than the underscanned pixels: judging by the small gap between the two large rocks in the very bottom left hand corner, you maybe cropped 10 pixels and zoomed. It looks damn good. I'll try this in Premiere and see how well it works.
AlexOsadzinski is offline   Reply With Quote
Old April 25th, 2002, 11:18 AM   #11
 
Join Date: Nov 2001
Location: santa fe, nm
Posts: 3,264
Images: 10
Indeed, it was a "symetrical" crop. That is to say I cropped the entire perimeter(all four sides) of the frame by the same amount.
Bill Ravens is offline   Reply With Quote
Old April 25th, 2002, 01:20 PM   #12
Wrangler
 
Join Date: Feb 2002
Location: Cleveland, Ohio
Posts: 1,933
bill's crop captures

1) I've been there!
2) Why are the images 816 x 1056? What happened to good old 720 x 480? The aspect ratio isn't even preserved. Is this some kind of rectangular pixel issue?
3) Chris, whom have you talked to at Canon about this problem? I can think of two arguments against Canon's "there's nothing wrong with it!" position, if that is their position. First, the XL1S claims to be a still image camera, not just a video camera: it has a still image function. The border distortion is a serious issue for still images taken with the camera. Second, the XL1S's advertised resolution isn't being delivered if a fraction of those pixels are bad.

I haven't gotten around to pursuing this further yet, but I want my camera fixed. (On my camera the border appears both on the bottom and on the left of the frame.) This really shouldn't be an issue on a camera this expensive, when cameras a tenth this price have no border distortion and my old XL1 never had this problem.
__________________
All the best,
Robert K S

Search DVinfo.net for quick answers | The best in the business: DVinfo.net sponsors
Robert Knecht Schmidt is offline   Reply With Quote
Old April 25th, 2002, 01:28 PM   #13
 
Join Date: Nov 2001
Location: santa fe, nm
Posts: 3,264
Images: 10
whoa...slow down robertks. In order to make a composite image, I duped each frame capture into a single composite Photoshop image. I made no attempt to keep anything other than aspect ratio. Also, I should point out that I did an image grab from two separate video files, one that was the master original and one that was cropped. I made no attempt to grab the identical image frame. The sequence was undergoing a zoom operation...the point is while they are within a few frames of one another, if you compare border details, you may not be able to deduce the actual crop size....sorry about that.

Secondly, I agree that it is apalling that a camera as "professional" as the XL1s has this kind of sloppy quality control. However, I will note that my old Sony VX1000 had an identical problem, altho' it was on the left vertical edge of the frame.

Last edited by Bill Ravens; April 25th, 2002 at 01:50 PM.
Bill Ravens is offline   Reply With Quote
Old April 25th, 2002, 02:57 PM   #14
Wrangler
 
Join Date: Feb 2002
Location: Cleveland, Ohio
Posts: 1,933
Ah, I see now--it's one image file being displayed, not two separate images.
__________________
All the best,
Robert K S

Search DVinfo.net for quick answers | The best in the business: DVinfo.net sponsors
Robert Knecht Schmidt is offline   Reply With Quote
Old April 25th, 2002, 03:44 PM   #15
Wrangler
 
Join Date: Sep 2001
Location: Northern VA
Posts: 4,487
Perhaps Canon's position is that it is a video camera, not a still camera. Therefore image artifacts will into the overscan area are not a defect. If it is the same on all units, it is not a QC issue, it is a design issue.
Don Palomaki is offline   Reply
Reply

DV Info Net refers all where-to-buy and where-to-rent questions exclusively to these trusted full line dealers and rental houses...

B&H Photo Video
(866) 521-7381
New York, NY USA

Scan Computers Int. Ltd.
+44 0871-472-4747
Bolton, Lancashire UK


DV Info Net also encourages you to support local businesses and buy from an authorized dealer in your neighborhood.
  You are here: DV Info Net > Canon EOS / MXF / AVCHD / HDV / DV Camera Systems > Canon HDV and DV Camera Systems > Canon XL and GL Series DV Camcorders > Canon XL1S / XL1 Watchdog

Thread Tools Search this Thread
Search this Thread:

Advanced Search

 



All times are GMT -6. The time now is 03:52 PM.


DV Info Net -- Real Names, Real People, Real Info!
1998-2024 The Digital Video Information Network