XL2 image problem

[Josh Bass]

I got bored and tried the photoshop test, and it looks exactly like moired image when you apply the deinterlace filter. I don't know if this means anything, and I'm not trying to fuel anything, but it's just to let y'all know.

[Stefan Scherperel]

<<<-- Originally posted by Nick James : Sorry, but it's most certainly deinterlacing. There is no doubt.


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...

:) -->>>

Nick, I would have to dissagree with you on this one. While progressive footage will look best on progressive scan TV's, progressive footage works great on interlaced television as well. In fact, you should not be limited in any wayt that you shoot, because progressive footage has a much different asthetic than interlaced footage. IF everything that was shown on interlaced televisions was interlaced then you could say bye bye to your DVD collection, lots of nightime drama shows and sitcoms witch are shot on film or progressive HD. Progressive footage displays fine on interlaced TV's and even interlaced footage can display moire problems like that described by Clive.

[Barry Goyette]

The fact that the moire is visible on a monitor, but not in the image is no great mystery. I did a test with my DVX the other night, shooting a test chart designed to produce a moire, or rather lots of them. Viewing the image through the LCD produced wild, crazy moires, while viewing through an NTSC monitor produced a very strong set of patterns as well. When I imported the footage I was not surprised to see that the moires had almost disappeared..still evident but much less noticeable...but more interesting was this....the moires on the actual image were different moires than the ones appearing on both monitors during filming. This make sense because the varying resolutions of said monitors are going to interact with the source pattern each in a different manner.

The pattern of the bricks alone in clives footage (as charles alluded to in his post about shooting film) would (or at least could) cause moires on a monitor without the actual recorded image having any.

Now regarding the interlace thing...we're really talking about the same process except we're creating it in the image instead of viewing it on a monitor. We have an image that has a pattern with no noticeable moire (there is actually a very slight one, but it is almost invisible)..photoshop's deinterlace filter does little more than halve the vertical resolution by either blending alternating lines or, throwing away one set and doubling the other...so essentially it has lowered the "output" resolution overlaying the pattern...producing a moire...you can produce almost the same result by resizing the image to 50% using nearest neighbor interpolation (bicubic..which is photoshops default is designed to avoid such patterning). So in a nutshell...deinterlacing in itself has nothing to do with this except in that it is lowering the vertical resolution of the image...

(one more thing...try the deinterlace trick and then toggle between the before and after zoomed way in...you'll start to see the slight moire in the actual image that I mentioned above..and you'll notice that the deinterlaced one is opposite in value from barely perceptible one in the image.

Barry

[Jay Gladwell]

I tend to agree with Jeff. He's being more subtle than I would. As this thread has progressed and as I've watched what Clive has posted, or more importantly hasn't posted, I've been led to think he has an agenda. I can't say what that agenda is, because I don't know. It reads to me like we're being baited, and in my mind, this whole thing is suspicious. Frankly, I don't appreciate such tactics.

Jay

[John Wheeler]

Received my XL2 yesterday, had a chance to play with it tonight. I hate to be negative, because I want this camera to be awesome more than anyone else. Pulled the pieces from the box, assembled it, threw in a tape, and started recording. The only option i changed ..was the frame rate ..i set it to 24p ...recorded 3 minutes of footage around the living room. ...hooked the video cables to the tv (standard 4:3 tv) ...hit play ....and instantly noticed very significant and distracting "moire" or "artifacting". ...I'm not an expert, so I cant say whether it's moire or artifacting or both. The main objects I noticed it on were the wooden shutters in the windows, and the frames of pictures, hanging on the wall. .....I started playing around a little bit ..and just kind of looked at the camera, then i switched it back to manual mode, while still hooked up to the TV ...I left the camera on top of the tv aiming at the walls with the shuttered windows ......And I noticed "flickering" around the edges of the shutters.?? Note that the camera wasnt moving at all. .

So ...I guess I'm not sure what to do.

Also ...has anyone noticed in 16:9 mode ...when looking through the VF ....do you notice the letterboxed area on top ..kind of flickering? ...

Some positive comments:

This puppy is built pretty solidly. I mean, it feels rock solid. Very impressed with that. I owned the DVX100 ...pulled it from the box, was disappointed with the build. It felt cheap. So I sent it back the next day.

The xl2 ...just looks beautiful. To me, the looks of the camera alone are worth $2,000.

The little bit of recording I did around the house, I was very impressed with the color reproduction.

Was also very impressed with the low noise in "dark" situations.


Keep in mind, I've only recorded about 10 minutes worth of footage. I'm worried about the moire problem, but I am so impressed with the camera, overall, that I'm going to keep it, ..and hope that I can "learn" how to minimize the appearence of the moire ....assuming that the moire problem isnt a defect, but rather just the "nature of higher definition cameras" as stated on this forum.


j.

[Daniel von Euw]

Can you upload or send a dv sample to show the moire effect???


regards
Daniel

[David Lach]

You know, I see moire all the time when watching TV on a 32" set, especially the typical interviews with some guy who wears a fine stripped shirt, and this is usually shot using broadcast camcorders with broadcast 2/3" lenses, so I'm tempted to ask, what else is new?

Did people expect this problem (which is more IMO a weakness of our interlaced monitor systems in general than the cameras used to shoot for them) to magically disappear with the XL2?

I mean, I'm no expert, but if you shoot progressive, edit progressive and then see the footage on an interlaced monitor and it has moire visible, wouldn't it point to the monitor being the problem instead of the camcorder?

Because as far as I know, a true progressive scanned image is supposed to be like a digital photo, without interlaced lines of resolution, so this shouldn't influence the output. What might influence it (again, I would think) is the level of sharpness in the image, a sharper image being more inclined to show moire than a softer one, because the latter kinds of smooths any fine lines in the details (kind of like anti-aliasing on a computer).

So if this is correct (and please do tell if I'm wrong), the best solution would be to shoot with the XL2 with details set at "high" and then, if you see problems on an interlaced monitor, just apply some kind of anti-aliasing filter just on the scene(s) that causes problems in post-production. If you plan on transfering to film, this shouldn't be a concern at all I would assume.

[Jim Giberti]

Anyone how cared to notice would have seen the same thing on NBC's Olympic broadcast for a good example. Take the track sports and look at the white painted lines on the tracks....moire. Fortunatley only video geeks would be looking at the white line patterns instead of the Olympic action.

[Antoine Fabi]

yep,

if you watch carefully a Hoolywood DVD (film to very very high quality CCDs transfert), then you'll see tons of these. It is normal when you watch high res progressive footage on an interlaced TV monitor.

[Richard Alvarez]

A great book on Communications, "How Real is Real" has a story about perception/reality in it. Apparently, during the late fifties, while the atomic testing was going on in the desert... a story went round that the fallout was drifting onto windshields, and causing pitting. People started to look at their windshields, and sure enough, there was significant pitting going on. Enough for the government to do a study.

What they found out was that windshields ALL OVER the US were pitted. What had taken place was not an increase in pitted windshields, but an increase in LOOKING AT WINDSHIELDS. What people had been looking THROUGH all of their life, they were now looking AT.

Funny how that works.

[Jim Giberti]

<<Funny how that works.What they found out was that windshields ALL OVER the US were pitted. What had taken place was not an increase in pitted windshields, but an increase in LOOKING AT WINDSHIELDS. What people had been looking THROUGH all of their life, they were now looking AT.>>

This would be the source of a great thread in and of itself Richard. It really speaks to one of the core issues of discussing the technology of, in this case, a video camera, versus the percieved results it delivers, because after all perception is everything and especially when we're producing stuff for the masses (no matter how big those masses).

I understand but still shake my head at post after post here and a couple of other places (music and film/video production). It's been a given to me for a long while that if you have tools that deliver at a certain level, it's encumbent upon you to "play" them well.

I've known so many great players who could bring tears to your eyes on a $100 Silvertone guitar, and yet people with a fraction of that talent will spend years of their short lives debating the finer points of the most expensive instruments and criticising every little fault of the less than top shelf stuff. All the while the great creatives continue to do great creative with whatever tools they have at hand or can afford.

My personal read is this: whether the XL2 exceeds or falls short of beta or digibeta quality, whether it's percieved as "better" in some aspects that a DVX or whatever camera, or worse, we're counting the number of angels on a pin head here.

The XL2 has acheived a level as a creative tool, that for me at least, exceeds my and most people's ability to maximize. The images are just wonderful, and the freedom of it's simple power system, lens capabilities, monitoring etc. create just exactly that...freedom to grow creatively without the encumberances of more "involved" technology.

I guess what I mean is that if you're a really good shooter, film maker, what ever, you can certainly bring tears to peoples eyes with this camera, and that's all that's ever really made sense to me creatively.

[Antoine Fabi]

oh...

so true...

I'm a musician, and i perfectly understand what you mean.

great wisdom words Jim

regards

[Robin Davies-Rollinson]

Amen to that Jim!
(I think I'll be quoting from you - if you don't mind ...)

Robin

[Jay Gladwell]

It's been a given to me for a long while that if you have tools that deliver at a certain level, it's encumbent upon you to "play" them well. Jim Giberti

Jim, I couldn't agree with you more! I recall a story from my college days back in the late 60s or early 70s. As a commercial art majors, we studied, among others, Ansel Adams. After a very few days many of the students began to claim that if they had a large format camera, 4x5 or better, like Adams, their photographs would be better than those taken with their 35mm Pentax. Hearing enough of this nonsense our wise professor, Darryl Degelman, pulled out some copies of beautiful b&w photographs and showed them to us. "Who do you think took these?" he asked. Well, it was obvious from the style these photographs were taken by Adams. Then he showed us a picture of the camera Adams had used--a simple, self-made pinhole camera! Mr. Degelman went on to say that it's not the equipment that makes beautiful photographs, it's the artist.

At the risk of sounding like I'm tooting my horn, I'll tell you about the greatest "professional" compliment I ever got. It was about a year ago. The phone rang. I answered it. It was someone inquiring about our work, mentioning that they had seen the sample footage on our web site. During the course of our conversation, the fellow paid me several kind compliments about how nice the images were. Then he asked me a question that both floored me and elated me, "Did you shoot this footage on film?" It has never been a goal of mine, to make video look like film, but I was deeply honored that he felt like he had to ask to be sure. I explained that the footage was shot with the XL1 and XL1s cameras.

Now, some reading this will say it's obvious that guy had no experience, since the differences between film and video are obvious, and on and on and on. But the man on the other end of the line was (and still is) a long time member of the DGA (Directors Guild of America) who has done extensive work in film and video directing and shooting thousands of television commercials that we've all seen and loved.

My point is, I've read so much crap here, and elsewhere, that the XL cameras are not all they're hyped up to be. The auto lenses are garbage. MiniDV is a joke. Video images suck compared to film. You can't shoot anything serious on video. Don't use any of the XLs, you'll have to rent something costing tens of thousands more. Blah, blah, blah. You've read it all before, too. And it just goes to show how little these wannabes really know and/or understand about creating images.

The bottom line is: Know your instrument. Just learn what it can and can't do, then do the best you can with it--whatever it is!

My apologies for being so long-winded. And thank you, Jim, for your consistently wise and well-balanced input here!

Jay

[Gary McClurg]

Amen