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-   Sony XDCAM EX Pro Handhelds (https://www.dvinfo.net/forum/sony-xdcam-ex-pro-handhelds/)
-   -   Vignette problem (https://www.dvinfo.net/forum/sony-xdcam-ex-pro-handhelds/108433-vignette-problem.html)

Dave Elston November 22nd, 2007 01:36 PM

Quote:

Originally Posted by Bill Spence (Post 780187)
It almost looks as if the Sony matteboxe was casting a shadow on the corner from an overhead light and as the angle of the light changed, so did the "vignette".

Bill, the vignette problem that Paul had experienced was limited to a narrow zoom window, it did not manifest itself at full wide which would suggest it is either something inside the lens that is encroaching on the optical path OR simply the natural fall-off of the lens becoming exposed within the active area of the imagers.
The tennis clip is demonstrating a lesser amount of vignetting and only becomes apparent during the camera move (whip-pan) suggesting that it may be associated with the OIS system over-correcting.

While both examples could be caused by two unrelated issues, the fact that the vignette is in the same corner would suggest (whatever the cause) the obstruction/fall-off is the same in both cases. The only way to test properly is to shoot an evenly lit cloth and carry out pans and zooms at various settings.

We should not attempt to draw any final conclusions from just the first handful of clips that the 'lucky few' are posting, although by all means people, keep them coming!

Paul Joy November 22nd, 2007 02:05 PM

1 Attachment(s)
I just did one last test with the camera in a real worst nightmare vignetting setting. The camera was facing blank wall which is too close to focus on properly.

I set the camera at 720/50p / shutter 100 / iris fully open. I then used the shot transition function to create a 10 second transition from fully wide to fully zoomed.

The results show that it is indeed actual vignetting, it happens on all four corners with the top left being the worst. At the furthest reaches of zoom a full vignette pattern is applied to the image.

See the attached movie.

Paul.

Phil Bloom November 22nd, 2007 02:14 PM

It looks like your camera Paul is a lemon unfortunately. The one I used today exhibited nothing like what you experienced. Hopefully your new one will be much much better.

Now, are you returning it to your dealer (who aren't a sponsor so I cannot mention them) and hope they will get one in for you soon...or are you returning it to Sony using silver support meaning they have to fix it within ten working days or they give you a loan EX1?

Eric Pascarelli November 22nd, 2007 02:16 PM

Paul,

That's pretty apparent - some sort of internal vignetting.

If you still have your camera out, perhaps you could put a piece of tape or something in the middle of the frame? This would show where the zoom begins and ends (even if it's out of focus). Also, if you make the shot transition curve linear we'd be able to find the spot on the zoom where it happens and compare it to other cameras (such as mine when [if?] it arrives).

Dave Elston November 22nd, 2007 02:20 PM

Thanks for unwrapping her for one last time Paul!

That's a very telling clip, the problem looks like the lens is not quite large enough to fill the imagers at some points. While I would perhaps expect some degree of fall-off to be noticable at the long end of the zoom there should be no obvious problems going wider.

Definitely a focus/optics mis-match going on, as was (according to Sony) the case for Adam Wilt's review model.
I would think/hope this is a problem that should be limited to only a handful of the very earliest shipments slipping through Sony QC.

Dave Elston November 22nd, 2007 02:28 PM

Quote:

Originally Posted by Eric Pascarelli (Post 780219)
If you still have your camera out, perhaps you could put a piece of tape or something in the middle of the frame?

...and (OIS ON) do a pan or tilt move at the worst zoom-point to see how severely the OIS worsens the effect.

Unless you'd prefer to put her to rest more peacefully ;(

Steve Shovlar November 22nd, 2007 02:30 PM

Interesting reading about this vingetting problem.

I hope Paul they have a camera for you straight away. If I found a fault like this I would want an immediate swap. Anything else is unacceptable.

Paul Joy November 22nd, 2007 02:33 PM

Phil > It's being returned for a full refund.

Dave > I'm afraid it's in there for good now, but the clip I uploaded was shot using the shot transition function of the camera with the curve set to linear. In effect if you drag the play head to the middle of the clip, it's at the mid zoom range.. etc etc. There's around a second handle each end of the clip. OIS was off, but to be honest I don't think it's anything to do with OIS, it looks like the lens could do with being 82mm instead of 77


regards

Paul.

Sebastien Thomas November 22nd, 2007 04:32 PM

Paul, I'm sorry to ask here, but I saw the picture of the (peli)case you have for the EX1. Could you tell which size is it ?
Sorry for your problems with the cam.

Thanks.

Paul Joy November 22nd, 2007 06:11 PM

Hi Sebastien, no probs at all. The case is a Peli 1560. I think this is the smallest peli case that the EX1 with fit in due to it being quite wide and tall. I originally planned to place the camera in the case upright (handle up). The camera does fit that way up but the top of the case almost touched the top of the viewfinder and I was worried that pressure on the case during travel might damage the camera.

I've now shaped the foam to allow the camera to sit on it's side (grip down) which provides a lot more protection. As you can see it also leaves quite a bit of room for other bits and bobs you might want to put in there too.

Paul.

Sebastien Thomas November 23rd, 2007 02:26 AM

I read the specs of the camera, which is 20cm x 20cm x 40cm. The Pelicase you are using is less (17cm tall). But maybe the foam is compressed but it goes well ? or maybe the camcorder is less tall than specified in the doc ?

If you're right I'll buy one too.

Thanks.

Ken Hull November 23rd, 2007 02:26 AM

Focus point affecting vignette problem?
 
Just wondering if anyone has tried a few different focus points while doing these vignetting tests. Maybe point the camera at a blank wall or ceiling, set the focus to infinity and zoom through the range, then do the same with focus set to about one meter.

Paul Joy November 23rd, 2007 02:41 AM

Quote:

Originally Posted by Sebastien Thomas (Post 780469)
The Pelicase you are using is less (17cm tall).

No it's not, the internal dimensions of the 1560 are 51.7 x 39.2 x 22.9 cm.

regards

Paul.

Sebastien Thomas November 23rd, 2007 03:02 AM

Just think I'm still sleeping. Forget my previous post, I was looking at the 1520...
Maybe I'm too stressed waiting for the EX1 to arrive...

Paul Joy November 23rd, 2007 03:39 AM

I've created a new thread for cases Sebastien as I'm sure it will be a popular topic and this thread would probably be the wrong place for it to happen.

http://dvinfo.net/conf/showthread.php?p=780499

regards

Paul.


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