CA Sample? at DVinfo.net

Joseph H. Moore · October 14th, 2005, 02:09 PM

Could someone post a frame that showcases the built-in lens' chromatic aberation? Either a natural image or a test chart would do. I'd like to test how well a filter for removing it in Post performs.

Barry Green · October 14th, 2005, 03:33 PM

http://www.icexpo.com/HD100/Fringe-1.PNG

Joseph H. Moore · October 14th, 2005, 03:39 PM

Yikes! I didn't realize it was so severe ... I was expecting something typical to an average quality still digital camera's lens. I wonder what I can do with this...I'll report back.

Barry Green · October 14th, 2005, 04:06 PM

That's an extreme example, of course. The CA depends on the telephoto setting; the more telephoto, the more noticeable CA is. Wide-angle shots are a lot more mild; and, most digicams have very limited zoom ranges.

I have many other examples if you need 'em, or full-frame shots, etc. If you're able to come up with something that fixes this, you would be doing the HD100 community a great favor!

Joseph H. Moore · October 14th, 2005, 04:16 PM

Unfortunately this is not true lens based chromatic aberation in the classical sense, but rather the dreaded "purple fringing" that is caused/exascerbated by small size CCD sensors.

Which is to say that the base Fujinon lens is not the major culprit ... it's a factor ... but not as much as the electronics. I had not seen a sample until now, so I was hoping it was true lens-based CA. (I plan on using good 35mm lenses, and that kind of CA is easy-breezy to auto-fix in post.)

I will play with this because it is possible to come up with a decent post fix ... but ... it won't be something that you can apply wholesale, rather it will have to be used selectively on just the clips that need it.

Joseph H. Moore · October 14th, 2005, 04:37 PM

Well, it's far from perfect, but it can be filtered somewhat sucessfully:

http://www.12south.com/catest/Fringe-1.jpg

It's not ideal but at least you could save a shot if you had to.

Barry Green · October 14th, 2005, 04:48 PM

Interesting. Most interesting.

Try this one:
http://www.icexpo.com/HD100/Branches.png

Michael Maier · October 14th, 2005, 07:20 PM

I think JVC should have sold the camera without lens, as any pro camera sells. Then they could offer the 13x wide angle for 10k and another non wide angle lens for the same price. Then we would have nobody whining about the quality of a "give away" HD lens, ridiculously price at a low (read insignificant for being HD, since the horrible fuji 14x that came stock with the DV500 cost that) 800 bucks. So people would have to really fork for the money, instead of whining for something they are not paying for. Then after a couple of months, JVC could announce they would be introducing an entry level HD lens for $2,000, and release this 16x. Even selling for more, it would be received as the savior of indie filmmakers. People would be thankful for they being able to at least buy this lens and shoot some HD, with CA or not, because they can't afford the higher end stuff. It would be CA or nothing.
Then we wouldn't have people jumping in every opportunity they have, and using the lens justified limitations to bash the HD100. We wouldn't have people complaining about the lens being lower quality, because they chose to buy the lower quality lens in the first place.
The interesting thing is that this is also true right now, since JVC doesn't make you buy the camera with the 16x. You can go for the 13x. At least they give you another option. If it's not out yet, then wait and don't complain.
Funny how perspective can change things around.

Werner Wesp · October 15th, 2005, 05:09 AM

Indeed Michael, I'm under the impression that a lot of the interested people overlook the fact they're dealing with the pro-division of JVC (or just never ahd any pro-division-product)....

Thomas Smet · October 15th, 2005, 10:22 AM

This goes back to my thread about how It is Fujinon we should be looking at for the bad lens and not JVC. If the camera would have been sold without the lens than nobody could say JVC was bad but that they just had to buy a bad lens because it is all they could afford at the time. As it is now I can see people always pointing at JVC for the bad lens on the HD100 just because they gave it to us with the camera.

Joseph H. Moore · October 15th, 2005, 10:48 AM

IT'S NOT THE LENS!!!

The lens is a part of the problem, to be sure, but it's an inherent, not really well understood, problem with small size CCD's.

Google "Purple Fringing." This is not traditional lens based CA.

Greg Boston · October 15th, 2005, 11:10 AM

BTW Joseph, I was looking at the specs for the latest version of Paint Shop Pro (now a Corel product) and saw it listed a 'purple fringe fix' filter. I have some still images I would like to try it on, just haven't had time to download it yet.

-gb-

October 14th, 2005, 02:09 PM	#1
Joseph H. Moore Major Player Join Date: Oct 2005 Posts: 362	CA Sample? Could someone post a frame that showcases the built-in lens' chromatic aberation? Either a natural image or a test chart would do. I'd like to test how well a filter for removing it in Post performs.

October 14th, 2005, 03:33 PM	#2
Barry Green Barry Wan Kenobi Join Date: Jul 2003 Location: North Carolina Posts: 3,863	http://www.icexpo.com/HD100/Fringe-1.PNG

October 14th, 2005, 03:39 PM	#3
Joseph H. Moore Major Player Join Date: Oct 2005 Posts: 362	Yikes! I didn't realize it was so severe ... I was expecting something typical to an average quality still digital camera's lens. I wonder what I can do with this...I'll report back.

October 14th, 2005, 04:06 PM	#4
Barry Green Barry Wan Kenobi Join Date: Jul 2003 Location: North Carolina Posts: 3,863	That's an extreme example, of course. The CA depends on the telephoto setting; the more telephoto, the more noticeable CA is. Wide-angle shots are a lot more mild; and, most digicams have very limited zoom ranges. I have many other examples if you need 'em, or full-frame shots, etc. If you're able to come up with something that fixes this, you would be doing the HD100 community a great favor!

October 14th, 2005, 04:16 PM	#5
Joseph H. Moore Major Player Join Date: Oct 2005 Posts: 362	Unfortunately this is not true lens based chromatic aberation in the classical sense, but rather the dreaded "purple fringing" that is caused/exascerbated by small size CCD sensors. Which is to say that the base Fujinon lens is not the major culprit ... it's a factor ... but not as much as the electronics. I had not seen a sample until now, so I was hoping it was true lens-based CA. (I plan on using good 35mm lenses, and that kind of CA is easy-breezy to auto-fix in post.) I will play with this because it is possible to come up with a decent post fix ... but ... it won't be something that you can apply wholesale, rather it will have to be used selectively on just the clips that need it.

October 14th, 2005, 04:37 PM	#6
Joseph H. Moore Major Player Join Date: Oct 2005 Posts: 362	Well, it's far from perfect, but it can be filtered somewhat sucessfully: http://www.12south.com/catest/Fringe-1.jpg It's not ideal but at least you could save a shot if you had to.

October 14th, 2005, 04:48 PM	#7
Barry Green Barry Wan Kenobi Join Date: Jul 2003 Location: North Carolina Posts: 3,863	Interesting. Most interesting. Try this one: http://www.icexpo.com/HD100/Branches.png

October 14th, 2005, 07:20 PM	#8
Michael Maier Trustee Join Date: Apr 2005 Posts: 1,269	I think JVC should have sold the camera without lens, as any pro camera sells. Then they could offer the 13x wide angle for 10k and another non wide angle lens for the same price. Then we would have nobody whining about the quality of a "give away" HD lens, ridiculously price at a low (read insignificant for being HD, since the horrible fuji 14x that came stock with the DV500 cost that) 800 bucks. So people would have to really fork for the money, instead of whining for something they are not paying for. Then after a couple of months, JVC could announce they would be introducing an entry level HD lens for $2,000, and release this 16x. Even selling for more, it would be received as the savior of indie filmmakers. People would be thankful for they being able to at least buy this lens and shoot some HD, with CA or not, because they can't afford the higher end stuff. It would be CA or nothing. Then we wouldn't have people jumping in every opportunity they have, and using the lens justified limitations to bash the HD100. We wouldn't have people complaining about the lens being lower quality, because they chose to buy the lower quality lens in the first place. The interesting thing is that this is also true right now, since JVC doesn't make you buy the camera with the 16x. You can go for the 13x. At least they give you another option. If it's not out yet, then wait and don't complain. Funny how perspective can change things around.

October 15th, 2005, 05:09 AM	#9
Werner Wesp Major Player Join Date: Aug 2005 Location: Belgium Posts: 497	Indeed Michael, I'm under the impression that a lot of the interested people overlook the fact they're dealing with the pro-division of JVC (or just never ahd any pro-division-product)....

October 15th, 2005, 10:22 AM	#10
Thomas Smet Trustee Join Date: Mar 2004 Location: Milwaukee, WI Posts: 1,719	This goes back to my thread about how It is Fujinon we should be looking at for the bad lens and not JVC. If the camera would have been sold without the lens than nobody could say JVC was bad but that they just had to buy a bad lens because it is all they could afford at the time. As it is now I can see people always pointing at JVC for the bad lens on the HD100 just because they gave it to us with the camera.

October 15th, 2005, 10:48 AM	#11
Joseph H. Moore Major Player Join Date: Oct 2005 Posts: 362	IT'S NOT THE LENS!!! The lens is a part of the problem, to be sure, but it's an inherent, not really well understood, problem with small size CCD's. Google "Purple Fringing." This is not traditional lens based CA.

October 15th, 2005, 11:10 AM	#12
Greg Boston Wrangler Join Date: Oct 2003 Location: DFW area, TX Posts: 6,117 Images: 1	BTW Joseph, I was looking at the specs for the latest version of Paint Shop Pro (now a Corel product) and saw it listed a 'purple fringe fix' filter. I have some still images I would like to try it on, just haven't had time to download it yet. -gb-