View Full Version : Vignette problem
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Piotr Wozniacki November 22nd, 2007, 09:05 AM You mean this?
Difficult to say whether it's the "vignetting" artifact, or just one of those ribs under the hall roof... Judging from their spacing, though, it shouldn't be there! On the other hand, considering fast pan - due to the rolling shutter everything is possible. Paul's were static examples.
Edit I posted two grabs on purpose; even if it may look like a part of the roof structure in the left (earlier) one, it shouldn't be there in the right (later) one! Seems like it's moving to the right with camera.
Dave Elston November 22nd, 2007, 09:18 AM That's exactly it Piotr, thanks for posting the grabs (I'm stuck on a work machine that can't frame-by-frame easily).
I don't believe it to be part of the background structure (see earlier frames), this example is only a slight intrusion compared to the problem Paul has experienced. Just seems to indicate an OIS issue is to blame as has previously been suggested.
Paul Joy November 22nd, 2007, 09:26 AM On the first image I would have said it's just the building, but in the second there is a dark area where the same area was not dark in the first image.
[Edit] you know, the more i look at this the more it looks very similar![/ edit]
Only the camera owner could answer for sure though.
Paul.
Steven Thomas November 22nd, 2007, 09:27 AM IMO, that does not look like vignetting. With all the quick pan motion blur, this is probably part of the background.
Also, I asked the camera owner to do a test a day ago. He said he would.
He has not mentioned any vignetting issues.
Piotr Wozniacki November 22nd, 2007, 09:28 AM On the first image I would have said it's just the building, but in the second there is a dark area where the same area was not dark in the first image.
[Edit] you know, the more i look at this the more it looks very similar![/ edit]
Only the camera owner could answer for sure though.
Paul.
Exactly Paul; this is why I posted both grabs!
Well, this would support my little theory earlier in this thread... Some design feature might cause all the cameras to be on the verge of vignetting (or whatever you call this artifact); most do not so the QC never noticed. But some do, and now Sony is inspecting and returning those faulty ones - hence the delay and shortages...
But I will ask again: did anybody try to shoot without the lens hood?
Steven Thomas November 22nd, 2007, 09:52 AM It possible, but at least looking at these two images which of course are not one for one. One is wider and at a slightly different angle. IMO, you can not tell anything from these images based on the FOV is different.
Dave Elston November 22nd, 2007, 09:57 AM Perhaps the decision to go with 1/2" sensors in a 1/3" form factor has forced all the optical elements/devices into a very narrow margin of the critical optical path - PLUS this is a first in lens design with the integration of "Full-Auto-Full-Manual" controls.
Hopefully just teething trouble that Sony will iron out completely in future production runs.
Paul Joy November 22nd, 2007, 09:58 AM I see what you're saying Steven, the second shot is wider and that could cause the roofline object to be staying in view. If you look at the two light objects leaving a trail each side of the net line at the back of the room though, the second image is definitely panned further to the right than the first one. I don't have the source file, does it show the shadow moving with the camera?
Sami Sanpakkila November 22nd, 2007, 10:02 AM Just a thought. Could hardly make a difference but does something happen inside the lens when you change from autofocus to true manual focus ie. pull the focus ring back?
Those who have it have you tried to see if the vignetting appears both on manual and auto focus setting?
Sami
Paul Joy November 22nd, 2007, 10:02 AM Perhaps the decision to go with 1/2" sensors in a 1/3" form factor has forced all the optical elements/devices into a very narrow margin of the critical optical path
Lets hope the fix isn't to install a set of 1/3" sensors :)
Paul Joy November 22nd, 2007, 10:10 AM Those who have it have you tried to see if the vignetting appears both on manual and auto focus setting?
It makes no difference, neither does setting OIS on/off.
Dave Elston November 22nd, 2007, 10:14 AM neither does setting OIS on/off.
Paul, are you able to verify that OIS itself is actually working when it is ON?
Just a guess that it is possibly 'stuck' or mis-aligned in a far-left bias, causing the vignette.
Steven Thomas November 22nd, 2007, 10:23 AM Paul, are you able to verify that OIS itself is actually working when it is ON?
Just a guess that it is possibly 'stuck' or mis-aligned in a far-left bias, causing the vignette.
Now that's a good question.
Paul Joy November 22nd, 2007, 10:24 AM Sorry the camera is all boxed up now and awaiting collection.
Dave Elston November 22nd, 2007, 10:32 AM Sorry the camera is all boxed up now and awaiting collection.
No sweat, in any case it seems certain you have a faulty product deserving of replacement. I just hope you're not left 'waiting at the altar' too long.
(Just because it's better to have loved and lost than to have never loved at all ...it doesn't make losing any easier!)
Paul Joy November 22nd, 2007, 10:34 AM Just because it's better to have loved and lost than to have never loved at all ...it doesn't make losing any easier!
:( I miss her already!
Dave Elston November 22nd, 2007, 10:48 AM :( I miss her already!
Just keep telling yourself you've done it for the right reason.
OK, so you could have 'lived with it' but eventually, deep down, you know things would get ugly.
Sending her back home was the best thing for both of you, and still you had a passionate three day affair to remember her by. That's more than most of us!
Guys, Paul needs some group help at this difficult time!
Paul Joy November 22nd, 2007, 11:00 AM Lol, if Piotr's theory does turn out to be true then I'm sure we'll all be getting fixed cameras anyway. If anyone ends up with S/N 0400172 treat her with care, she's had a hard start in life :)
Piotr Wozniacki November 22nd, 2007, 11:07 AM Lol, if Piotr's theory does turn out to be true then I'm sure we'll all be getting fixed cameras anyway. If anyone ends up with S/N 0400172 treat her with care, she's had a hard start in life :)
Thanks fro that info, Paul! Now we are in the same boat - waiting. Hard time, isn't it?
Paul Joy November 22nd, 2007, 11:41 AM Hard time, isn't it?
Yup, left feeling empty...
Anyway, we're supposed to be professionals.... enough of this humor already!
Stelios Christofides November 22nd, 2007, 01:01 PM What is Vignette?
Stelios
P.S. Sorry found the answer in Wikipedia
"In photography and optics, vignetting is a reduction of an image's brightness or saturation at the periphery compared to the image center."
Bill Spence November 22nd, 2007, 01:09 PM OK, I have been following the posts on the EX1 for several months now and have had hi hopes for this camera, and still do. Some of the vignetting problems discussed were casting a little rain on my parade and so I took all of the footage I have downloaded from these sights onto a Vegas timeline and went through it frame by frame. Something is definitely there, but I am not convinced yet that it is vignetting from the lens. I say this because in the shots where I saw it, neither the focal length or the iris was being altered, only the angle of the camera. I saw it come and go during motion in the tennis shots that were discussed in this post earlier. And since it was not there all the time is why I am not convinced that it is vignetting. 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". In outdoor shots during the rain where the light is difuse and even, there is not evidence of it at all. This is all just specualtion since I don't have a camera infront of me, but I am not convinced yet that it is a lense issue as much as a physical issue that with a little more testing can be narrowed down.
Wesley Alfvin November 22nd, 2007, 01:09 PM What is Vignette?
Stelios
Stelios,
On at least 2 models of the EX1 (Paul's and an online reviewer's) a small shaded area is appearing mid-zoom in the upper left corner of the picture when the iris is fully open. Check out the first page of this forum to see an example.
Wesley
Craig Seeman November 22nd, 2007, 01:33 PM I reread this from Adam Wilt's look at a preproduction model.
"There is vignetting at wide apertures from 10mm onwards, but Sony tells me that it's due to a bug in this engineering sample's auto-focus system, so I'll refrain from further commentary until I have a production model to work with."
I wonder if anyone with camera can turn on/off auto focus and see if that has impact. It may be a few "bugged" models slipped through production. Some people raised suspicions about OIS but maybe it's the auto focus.
Phil Bloom November 22nd, 2007, 01:34 PM Got my hands on the EX1 finally today. Wow, it is lovely...the picture is astounding and that LCD screen?!? For 35mm adaptor work you won't really need an external monitor for focus with focus assist and expanded focus coupled with that resolution.
I tried to get the vignetting issues as described by Paul. I really struggled to find it. By pointing at a blank bright wall and zooming to around 10mm the worst I managed to get was this...you have to really look hard to see it. I see this as not a problem in the slightest.
Dave Elston November 22nd, 2007, 01:36 PM 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 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 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 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 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.
Joe Yaggi November 23rd, 2007, 06:43 AM [ If anyone ends up with S/N 0400172 treat her with care, she's had a hard start in life :)[/QUOTE]
It'll probably end up in Indonesia! At least I know which one to look for :)
Alessandro Zumstein November 23rd, 2007, 03:43 PM Hello, when you yuse a 35mm adapter, is cheaper when you "take the distance of the object and set it on the focus ring".
Alessandro Zumstein
Phil Bloom November 23rd, 2007, 03:55 PM sorry . don't understand
Robert Petersen November 23rd, 2007, 10:04 PM I took a clip (X02_0039_01.MP4 - indoor tennis) that was posted on this forum and played it in slow motion with the VLC player. There are a couple of places where you can clearly see the problem in the upper left corner. It shows up most prominently when the camera begins or ends a fairly rapid pan movement. It appears that the OIS is on, and is creating the vignette by trying to compensate beyond the capability of the lens. That's my best guess with the limited amount of video available.
If anyone has tested their EX1 and found no problem, it would be nice if they posted here so we can see the magnitude of the vignette problem.
Steven Thomas November 23rd, 2007, 10:17 PM Possible, but can you provide the actual frame grabs. This type of info really doesn't mean much to anyone without supporting it.
Christopher Barry November 23rd, 2007, 10:30 PM May I please have the link to the tennis footage? Thanks.
Steven Thomas November 23rd, 2007, 10:34 PM It's gone...
His host shut him off.
http://www.bolanski.com/ex/home/ex1-test-shots-part-2/
Christopher Barry November 23rd, 2007, 10:41 PM Thanks Steven. I hope someone has permission and puts up a mirror...
Chris Hurd November 23rd, 2007, 11:02 PM His host shut him off.*sigh*
This is exactly the reason why I offered to host it for him here on DV Info Net in the first place.
It's really too bad for everyone that he wouldn't take me up on it.
*shrug*
Steven Thomas November 24th, 2007, 12:38 AM Thanks Chris,
I'm not sure why he was hesitant with your offer.
Since he lost his host, maybe he'll change his mind
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