HC1 color fringing at DVinfo.net

Paul Nixon · February 8th, 2008, 10:13 AM

I was wondering if color fringing was normal for this (or any cam) when using zoom. I noticed that when I am at full zoom, the image there is a distinct green tint on one side of objects and a magenta tint on the other. This is most apparent when I'm trying to fake a DoF shot and have a foreground object in focus and the background blurred - you see the effect most in the blurred area, but the foreground object also doesn't look quite as sharp as it should.

I had thought this was because of a cheap ND filter or CP I was using in the past, but with this particular project I am working on, neither was being used.

Is this just "normal" for this level of camera?

Dave Blackhurst · February 8th, 2008, 01:40 PM

Strong backlights? I've noticed this "effect" when shooting indoors wiith bright windows - the bright areas seem to have a bit of fringing/CA on the bright dark transition. Haven't noticed it under other conditions though.

Paul Nixon · February 8th, 2008, 11:17 PM

Quote:

Originally Posted by Dave Blackhurst

Strong backlights? I've noticed this "effect" when shooting indoors wiith bright windows - the bright areas seem to have a bit of fringing/CA on the bright dark transition. Haven't noticed it under other conditions though.

No backlights at all in this case. I was outside on a cloudy day and noticed the fringing on light-colored background objects especially (like a white block wall). I had previously noticed the effect when using an ND filter in conjunction with a CP and thought cheap glass was the culprit. So this time I had nothing attached to the cam.

Take a look:
http://i120.photobucket.com/albums/o...orfringing.jpg

Dave Blackhurst · February 9th, 2008, 04:15 AM

white wall = "bright", and it's noticeable on that transition to the dark area. Not sure the cause, but seen it a few times. FX7 does it, so it's not necessarily a function of price...

Two possibilities, one being just the inherent challenge of CA (chromatic aberration), the other is that "sharp" transitions in brightness cause a problem for the HDV compression...

I've learned to ignore it when it pops up, although I've seen it quite severe with strong backlighting. Most people will never notice it...

Paul Nixon · February 9th, 2008, 09:26 AM

Quote:

Originally Posted by Dave Blackhurst

white wall = "bright", and it's noticeable on that transition to the dark area. Not sure the cause, but seen it a few times. FX7 does it, so it's not necessarily a function of price...

Two possibilities, one being just the inherent challenge of CA (chromatic aberration), the other is that "sharp" transitions in brightness cause a problem for the HDV compression...

I've learned to ignore it when it pops up, although I've seen it quite severe with strong backlighting. Most people will never notice it...

Now this is actually good news to some extent. My concern was that my camera had a problem. However, if this is "normal" than I'm probably okay. I'm in the process of assembling the parts for a 35mm DoF adapter that should resolve this problem (since I will no longer need to zoom in).

Thanks!

Christian de Godzinsky · March 17th, 2008, 06:49 AM

Hi,

I would consider this color fringing as "normal". This phenomenon is caused because less than perfect lenses, that are "streched" at high zooms. I have noticed the same behavior with my HC-1 already from day one. These lens color aberrations are especially visible with high contrast objects, just as you mention, with backlight objects and high zoom. You have to spend a lot more for the optics that would not show this behavior. That would not have left anything left for the electronics in HC1-1.

You just have to live with this. Not a very serious "problem" for a cam in this price category, but would be a serious flaw in a professional cam. Now you understand also why the optics is interchangeable in pro cams..

Christian

Paul Nixon · March 20th, 2008, 03:54 PM

Quote:

Originally Posted by Christian de Godzinsky

Hi,

You just have to live with this. Not a very serious "problem" for a cam in this price category, but would be a serious flaw in a professional cam. Now you understand also why the optics is interchangeable in pro cams..

Christian

What's funny is the Sony touts the "Carl Zeiss" lens implying that it is of superior quality. To what is the obvious question, eh?

I'm in the process of building a 35mm adapter so that should solve some issues, assuming a) I get it finished and b) it works as I hope. ;-)

Anyway, thanks for the reply.

Christian de Godzinsky · March 28th, 2008, 07:14 AM

Hi Paul,

Good luck with your adapter, would be nice to see and hear how it turned out.

Well, imaging how the image would look WITHOUT the Carl Zeiss optics ;)

Best regards,

Christian

February 8th, 2008, 10:13 AM	#1
Paul Nixon Regular Crew Join Date: Feb 2007 Location: Mesa, AZ Posts: 141	HC1 color fringing I was wondering if color fringing was normal for this (or any cam) when using zoom. I noticed that when I am at full zoom, the image there is a distinct green tint on one side of objects and a magenta tint on the other. This is most apparent when I'm trying to fake a DoF shot and have a foreground object in focus and the background blurred - you see the effect most in the blurred area, but the foreground object also doesn't look quite as sharp as it should. I had thought this was because of a cheap ND filter or CP I was using in the past, but with this particular project I am working on, neither was being used. Is this just "normal" for this level of camera?

March 17th, 2008, 06:49 AM	#6
Christian de Godzinsky Regular Crew Join Date: Dec 2005 Location: Helsinki/Finland Posts: 131	Hi, I would consider this color fringing as "normal". This phenomenon is caused because less than perfect lenses, that are "streched" at high zooms. I have noticed the same behavior with my HC-1 already from day one. These lens color aberrations are especially visible with high contrast objects, just as you mention, with backlight objects and high zoom. You have to spend a lot more for the optics that would not show this behavior. That would not have left anything left for the electronics in HC1-1. You just have to live with this. Not a very serious "problem" for a cam in this price category, but would be a serious flaw in a professional cam. Now you understand also why the optics is interchangeable in pro cams.. Christian __________________ The future does not exist - we must invent it !

March 28th, 2008, 07:14 AM	#8
Christian de Godzinsky Regular Crew Join Date: Dec 2005 Location: Helsinki/Finland Posts: 131	Hi Paul, Good luck with your adapter, would be nice to see and hear how it turned out. Well, imaging how the image would look WITHOUT the Carl Zeiss optics ;) Best regards, Christian __________________ The future does not exist - we must invent it !

February 8th, 2008, 01:40 PM	#2
Dave Blackhurst Inner Circle Join Date: Feb 2007 Location: Apple Valley CA Posts: 4,874	Strong backlights? I've noticed this "effect" when shooting indoors wiith bright windows - the bright areas seem to have a bit of fringing/CA on the bright dark transition. Haven't noticed it under other conditions though.

February 9th, 2008, 04:15 AM	#4
Dave Blackhurst Inner Circle Join Date: Feb 2007 Location: Apple Valley CA Posts: 4,874	white wall = "bright", and it's noticeable on that transition to the dark area. Not sure the cause, but seen it a few times. FX7 does it, so it's not necessarily a function of price... Two possibilities, one being just the inherent challenge of CA (chromatic aberration), the other is that "sharp" transitions in brightness cause a problem for the HDV compression... I've learned to ignore it when it pops up, although I've seen it quite severe with strong backlighting. Most people will never notice it...