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-   Sony HVR-V1 / HDR-FX7 (https://www.dvinfo.net/forum/sony-hvr-v1-hdr-fx7/)
-   -   Purple outline on background objects (https://www.dvinfo.net/forum/sony-hvr-v1-hdr-fx7/84937-purple-outline-background-objects.html)

Brian Rhodes January 28th, 2007 11:44 PM

Dave all shots were in manual mode and the bulit in ND FILTER on the V1 was in use mode 1 and mode 2.

Alphonse Swinehart January 29th, 2007 02:16 PM

Honestly, there are a ton of blocky artifacts throughout the entire frame. Almost like low quality DV25. I can't tell if this is the JPG compression you added when posting the image. See if you can post a PNG of the last two stills so we can take a better look.

Greg Boston January 29th, 2007 02:41 PM

Quote:

Originally Posted by Brian Rhodes
Thanks for the quick response guys.
Could my UV FILTER have caused the chromatic aberration to be more noticeable?

I started work on a short film last week just down loaded some of the footage it has the chromatic aberration also. I will call my dealer Monday and ask for a replacement unit. I never notice this on my Z1,FX1 OR A1U.

Alex there was another cameraman at the shot using a JVC GY-HD100U I will try to get some footage and compare.

The purple fringing on these two shots is more like CCD overload. I can and have induced the same effect with my Sony F350 and the HSs18x5.5 lens. You need to either bring up the light levels in the room with daylight corrected lights, or go outside and ND or scrim the window to cut down the light coming in. The effect gets worse at the ends of the lens coupled with wide open aperture. The camera is not at fault on these two shots.

We have some purple fringing shots in high contrast areas from the HD100 grabs in the Texas HD Shootout.

-gb-

Tony Tremble January 29th, 2007 03:48 PM

You don't tend to get CCD overload in a CMOS chip. :)

What ever the reason for the fringing it is also reproducible on CCDs and CMOS based cameras.

TT

Thomas Smet January 29th, 2007 03:52 PM

Why are these still images so blocky? To me that was as much a distraction as the purple fringing.

Brian Rhodes January 29th, 2007 03:52 PM

Quote:

Originally Posted by Alphonse Swinehart
Honestly, there are a ton of blocky artifacts throughout the entire frame. Almost like low quality DV25. I can't tell if this is the JPG compression you added when posting the image. See if you can post a PNG of the last two stills so we can take a better look.

I Changed the JGP compression to reduce the file size. I will post the video clips tonight. I aslo called BH to exchange the cam the Rep. advised me that it was over there 7 day return policy, So I am sending it to Sony so they can check out the cam. I am Very disappointed with BH.

Simon Hunt January 30th, 2007 11:42 AM

Has anyone tried using the "Knee Point" on the V1? This would be the ideal situation for it. High contrast with a very overexposed background. Try using "auto" and see what you get. I'm interested to know the results!

SH

Greg Boston January 30th, 2007 12:10 PM

1 Attachment(s)
Quote:

Originally Posted by Tony Tremble
You don't tend to get CCD overload in a CMOS chip. :)

What ever the reason for the fringing it is also reproducible on CCDs and CMOS based cameras.

TT

Purple fringing has been a problem for still camera sensors also. So let's just say it's 'sensor' overload. The problem is really bad with a high key light. See this attachment from a Kodak still camera of my friend's Harley.

Attachment 1976

Note the purple fringing where the front rim/tire meet as well as the handlebars with dark shadows. In short, a high contrast situation and a high key light (close to noon day sun..yuk). The aperture was f3.0 and shutter was at 1/750.

-gb-

Tony Tremble January 30th, 2007 12:36 PM

Quote:

Originally Posted by Greg Boston
Purple fringing has been a problem for still camera sensors also. So let's just say it's 'sensor' overload. The problem is really bad with a high key light. See this attachment from a Kodak still camera of my friend's Harley.

Attachment 1976

Note the purple fringing where the front rim/tire meet as well as the handlebars with dark shadows. In short, a high contrast situation and a high key light (close to noon day sun..yuk). The aperture was f3.0 and shutter was at 1/750.

-gb-

That is exactly what I saw on my V1 and now on my XH-A1. To be completely honest I don't find these flares distracting.

Ironically these flares are the things we spend a long time in post trying to simulate to make 3d renders look more "real."

TT

Greg Boston January 30th, 2007 02:06 PM

Quote:

Originally Posted by Tony Tremble
To be completely honest I don't find these flares distracting.

That's where you and I come at it from different perspectives. Those purple fringing halos stick out like a sore thumb to me. I absolutely feel that they kill the artistic vibe in my stuff. But to each his own. I have learned what situations produce this phenomena and I try to avoid them at all costs.

The two pictures in the earlier post I referenced appeared to be a staged shoot. I feel like there is ample opportunity to get rid of that stuff in that scenario. OTOH, if you're doing live stuff, it can't always be avoided. I've seen the blue edge on network HD golf broadcasts where they are live and have to get the shot, regardless of conditions. And once again, the commonality there is that the sun is high in the sky during the broadcast and a white shirt or white hat against a green background will produce blue flare on the right side of the subject (ie, a high contrast area).

-gb-

Bill Ravens January 30th, 2007 02:24 PM

well, i think you guys have put your finger on what I've been experiencing, re purple fringe...here -> http://www.geocities.com/ravens202/Image0.jpg

Lee Berger January 30th, 2007 03:09 PM

Bill,
At what focal length did you you shoot this this image?

Bill Ravens January 30th, 2007 03:26 PM

Lee..

shot with a JVC HD110 at full zoom, ie 85mm f/2.4 (Fujinon 17x5BRMU) HDV 24p....and you're looking at > 100% crop. The original image showed the purple fringe completely around the periphery of the target, i.e., no opposing green fringe, so it's not CA.

Steven Fokkinga January 30th, 2007 05:19 PM

Quote:

Originally Posted by Brian Rhodes
I Changed the JGP compression to reduce the file size. I will post the video clips tonight. I aslo called BH to exchange the cam the Rep. advised me that it was over there 7 day return policy, So I am sending it to Sony so they can check out the cam. I am Very disappointed with BH.

Are you sure you didn't recompress to mpeg or something before you made the jpg's? At this filesize (around 200kb) jpeg's shouldn't look like this. It almost looks like upconverted dv25, as someone else also mentioned...

Ken Ross January 30th, 2007 06:36 PM

I used to think there was a fair amount of fringing due to CA on the Sony FX7/V1, but when I see the fringing in almost all shots from the Canon A1/G1, I don't feel so bad. There's a current thread in the A1/G1 section on reducing noise, and in that section there's some posted jpegs. There's some really bad CA (or what looks like CA) on the Canon cams. By comparison, the Sony has a very minimal issue in this area.

The purple fringing in the bike shot above seems different to me than the fringing I'm discussing. The bike fringing is horrific and would drive me nuts if I saw it. It almost looks like 'blooming' on a CRT that's been overdriven.


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