vignette problem quick fix at DVinfo.net

Brian Jansen · November 30th, 2007, 03:44 PM

vignette problem no longer seen with lens shade removed. :)

Piotr Wozniacki · November 30th, 2007, 03:46 PM

Quote:

Originally Posted by Brian Jansen

vignette problem no longer seen with lens shade removed. :)

I kept asking people reporting this problem whether they actually did this test, but the answer was yes they did and vignetting was still there.

Robert Petersen · November 30th, 2007, 03:48 PM

Quote:

Originally Posted by Brian Jansen

vignette problem no longer seen with lens shade removed. :)

I don't understand how this could be an issue, since the reported problem was in mid-zoom. I guess you could have a unique problem.

Brian Jansen · November 30th, 2007, 03:53 PM

well, I see the issue quite clearly with the lens shade on, but not so doing
same exact test with it removed. Maybe a few others may/could confirm this.
I hope it's as simple as this.

Robert Petersen · November 30th, 2007, 03:56 PM

Quote:

Originally Posted by Brian Jansen

well, I see the issue quite clearly with the lens shade on, but not so doing
same exact test with it removed. Maybe a few others may/could confirm this.
I hope it's as simple as this.

I agree that this should be investigated; there may be some strange dynamic affecting the lens. I hope others will try it.

Eric Pascarelli · November 30th, 2007, 04:15 PM

My camera vignettes equally with or without the lens hood installed.

Brian Jansen · November 30th, 2007, 04:19 PM

man... thats weird. I tried it twice here too before I posted.
Glad you tried it, but I don't have an explaination for it.
I just know that I will be using a matte box or something other than
the shade whenever possible.

Steven Thomas · November 30th, 2007, 04:41 PM

When I first tried my camera, that's the first thing I tried.
No good.
Also, as it was mentioned it happens between 10mm-25mm not at it's wide position (5.8mm).

Brian Jansen · November 30th, 2007, 04:55 PM

well, I'm stumped. I'm shooting a decently flat lit white wall at about f11
Waveform shows nice flat line around 60IRE.
I just did test again both with and without.... AND NOTHING... looked fine.
I know I had the problem earlier and have a clip of it, AND I've seen it before.
So my current test proves nothing I guess.
Now I'm in TEST mode!

Piotr Wozniacki · November 30th, 2007, 05:00 PM

Open up from F11, please.

Steven Thomas · November 30th, 2007, 05:06 PM

You need to be at the widest aperture 1.9
Also pleasee use see the test thread:
http://dvinfo.net/conf/showthread.php?t=109119

Steven Thomas · November 30th, 2007, 06:24 PM

Chris, if you could, please remove this thread. There is no "quick fix" for the vignetting issue.

Brian Jansen · November 30th, 2007, 09:36 PM

Quote:

Originally Posted by Steven Thomas

Chris, if you could, please remove this thread. There is no "quick fix" for the vignetting issue.

I'll try recording a sample both with and without shade per your example.
I don't think deleting this thread is appropiate ... as I "do" have an EX-1 and am having similar, but mixed results and trying to help comfirm a possible mass problem.

Steven Thomas · November 30th, 2007, 09:46 PM

If it were a problem with the shade it would be at a wide open aperature (1.9 on the EX1) and with the zoom set to it's widest position (5.8mm).

Everyone else include Adam Wilt's pre-production EX1 shows the the issue in the 10-25mm range.

Please post samples with and without your shade on with your camera set to its widest zoom setting and your aperure set to 1.9 (open).

These are the settings that would show the lens hood if it were to cause vignetting.

Ken Hull · December 1st, 2007, 01:47 AM

I'm going to go out on a limb here, and suggest an explanation for how it could be the hood. Zoom lenses are complicated beasts with floating elements. I wouldn't be surprised if the nodal point shifts while zooming. Maybe at the widest angle, the nodal point is way out near the front element, and seeing "around" the edge of the hood. As you zoom in, maybe the nodal point shifts back and the hood comes into view.

Hey, its a theory. Probably could do a test with a piece of gaffers tape stretched across the hood, so it shows along the edge even when at f/8 or so.

My 2 cents worth, :)
Ken Hull

November 30th, 2007, 03:44 PM	#1
Brian Jansen Regular Crew Join Date: Aug 2006 Location: providence, RI Posts: 107	vignette problem quick fix vignette problem no longer seen with lens shade removed. :)

November 30th, 2007, 05:00 PM	#10
Piotr Wozniacki Inner Circle Join Date: Aug 2006 Location: Poland Posts: 4,086	Open up from F11, please. __________________ Sony PXW-FS7 \| DaVinci Resolve Studio; Magix Vegas Pro; i7-5960X CPU; 64 GB RAM; 2x GTX 1080 8GB GPU; Decklink 4K Extreme 12G; 4x 3TB WD Black in RAID 0; 1TB M.2 NVMe cache drive

December 1st, 2007, 01:47 AM	#15
Ken Hull Major Player Join Date: Nov 2007 Location: San Diego, CA Posts: 240	Here's a possibility ... I'm going to go out on a limb here, and suggest an explanation for how it could be the hood. Zoom lenses are complicated beasts with floating elements. I wouldn't be surprised if the nodal point shifts while zooming. Maybe at the widest angle, the nodal point is way out near the front element, and seeing "around" the edge of the hood. As you zoom in, maybe the nodal point shifts back and the hood comes into view. Hey, its a theory. Probably could do a test with a piece of gaffers tape stretched across the hood, so it shows along the edge even when at f/8 or so. My 2 cents worth, :) Ken Hull

November 30th, 2007, 03:53 PM	#4
Brian Jansen Regular Crew Join Date: Aug 2006 Location: providence, RI Posts: 107	well, I see the issue quite clearly with the lens shade on, but not so doing same exact test with it removed. Maybe a few others may/could confirm this. I hope it's as simple as this.

November 30th, 2007, 04:15 PM	#6
Eric Pascarelli Major Player Join Date: Nov 2007 Location: Los Angeles, CA Posts: 498	My camera vignettes equally with or without the lens hood installed.

November 30th, 2007, 04:19 PM	#7
Brian Jansen Regular Crew Join Date: Aug 2006 Location: providence, RI Posts: 107	man... thats weird. I tried it twice here too before I posted. Glad you tried it, but I don't have an explaination for it. I just know that I will be using a matte box or something other than the shade whenever possible.

November 30th, 2007, 04:41 PM	#8
Steven Thomas Trustee Join Date: Sep 2005 Location: Gilbert, AZ Posts: 1,896	When I first tried my camera, that's the first thing I tried. No good. Also, as it was mentioned it happens between 10mm-25mm not at it's wide position (5.8mm).

November 30th, 2007, 04:55 PM	#9
Brian Jansen Regular Crew Join Date: Aug 2006 Location: providence, RI Posts: 107	well, I'm stumped. I'm shooting a decently flat lit white wall at about f11 Waveform shows nice flat line around 60IRE. I just did test again both with and without.... AND NOTHING... looked fine. I know I had the problem earlier and have a clip of it, AND I've seen it before. So my current test proves nothing I guess. Now I'm in TEST mode!

November 30th, 2007, 05:06 PM	#11
Steven Thomas Trustee Join Date: Sep 2005 Location: Gilbert, AZ Posts: 1,896	You need to be at the widest aperture 1.9 Also pleasee use see the test thread: http://dvinfo.net/conf/showthread.php?t=109119

November 30th, 2007, 06:24 PM	#12
Steven Thomas Trustee Join Date: Sep 2005 Location: Gilbert, AZ Posts: 1,896	Chris, if you could, please remove this thread. There is no "quick fix" for the vignetting issue.

November 30th, 2007, 09:46 PM	#14
Steven Thomas Trustee Join Date: Sep 2005 Location: Gilbert, AZ Posts: 1,896	If it were a problem with the shade it would be at a wide open aperature (1.9 on the EX1) and with the zoom set to it's widest position (5.8mm). Everyone else include Adam Wilt's pre-production EX1 shows the the issue in the 10-25mm range. Please post samples with and without your shade on with your camera set to its widest zoom setting and your aperure set to 1.9 (open). These are the settings that would show the lens hood if it were to cause vignetting.