View Full Version : Vignetting with 20x zoom


Prech Marton
May 21st, 2004, 03:41 AM
I just wondering why does the picture vignetting if i zoom fully in.
Lens hood is on the cam.
The effect is very visible on pc/projector (outside the safe area), but it can be seen also on the TV (in the safe area).

Is this normal?

Frank Granovski
May 21st, 2004, 04:03 AM
Perhaps the hood (or filter) gets in the way?

Graham Bernard
May 21st, 2004, 04:21 AM
Nope . .not here, Standard and WD58H hoods on. You got any other stuff bolted on? Mics or floppy furries . . or loose women!!

Frank Granovski
May 21st, 2004, 04:26 AM
The last one sounds good.

Prech Marton
May 21st, 2004, 04:36 AM
Yes, it is the hood, because i don't have any filter, mic, etc.
just pure xm2.

i just wondering

Graham Bernard
May 21st, 2004, 04:44 AM
Prech, you sure it was the "standard" Canon hood that came with it .. ? We've been here before with "standard" - yeah? Can you share a picture of the hood you're having problems with?

No vinigretteables here . .

G

K. Forman
May 21st, 2004, 05:24 AM
I have the GL1, and have never noticed anything similar. In fact, the only problem I have had with the zoom, is the digital end seems to degrade the picture quality. I am looking to get a telephoto lens to extend it's range without using the digital zoom.

Is there such a thing as a wide angle telephoto lens adapter? For the GL1?

Frank Granovski
May 21st, 2004, 06:03 AM
Is there such a thing as a wide angle telephoto lens adapter? For the GL1?Nope. It's either a tele or a wide.

Ken Tanaka
May 21st, 2004, 10:46 AM
This is normal for certain iris settings. It's known as edge fall-off and it's a common characteristic for all lenses. I, too, was alarmed when I discovered this when the GL2 was first introduced.

Prech Marton
May 23rd, 2004, 03:05 AM
Here is a dv avi file, that show vignetting with original canon lens hood:

http://web.axelero.hu/prechj/pics/vignetting.avi

(6mb)

you can see, the effect is harder as i zoom in.

Barry Goyette
May 23rd, 2004, 11:21 AM
Prech

Ken is correct. This is one of the effects of putting a 20x zoom lens into a very small package. The effect shown in your clip is exactly that detailed in a very active discussion here from last year. (even the off-centered quality of the vignetting is pretty well documented). So there is nothing specifically wrong with YOUR camera, its just a limitation of the lens design that canon is using....oh, to have a $10,000 zoom on our $2000 cameras, that'd be nice huh?---You've exacerbated the issue by including a low detail, neutral sky in your frame...this will show inconsistencies like this more than a detailed, higher contrast shot.

You can minimize this effect by shooting with an aperture of f5.6 - f8, and by eliminating any gain (manual, or automatic) being applied to the image. Also shooting close-ups of zebras wouldn't hurt.


Barry