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jokefloreal
12-Apr-2007, 04:46
Hey,

When I look through my cambo with a 90mm lens I see that the borders are fluw and not sharp, but in de middle it is sharp! The last picture I took was also like this.....

It's like when the back is not put in a right-angle, but I checkt and everything is right!

with my 210mm I don't have it!
somebody knows what it is?
greets
joke

Ron Marshall
12-Apr-2007, 04:56
What 90mm lens is it? Can you explain a bit more please.

reellis67
12-Apr-2007, 05:30
It sounds like that lens does not fully cover the format. What size camera are you using this on? Also, which lens is it? Lastly, are you using movements when this happens or is it happening when the camera is set to the default positions?

- Randy

jokefloreal
12-Apr-2007, 07:14
Hey,
I use a Linhof super-angulon 8/90 schneider-kreuznach lens and 4x5 inch cassettes!
I use also very long exposers, but I know what kind of effect it has...and it's not like that!
I can see it also on the back when I put the image sharp!
Maybe because the lens and the back are very close together....
thanx for your reply's!
joke

C. D. Keth
12-Apr-2007, 18:58
Is it that the middle of the film is sharp and gets soft toward all the edges? OR is it that there is a line or strip that is sharp and it gets blurrier very fast as you go further from that line?

jokefloreal
13-Apr-2007, 05:59
It's that the film is sharp and gets soft toward all the edges....There is no line....

Leonard Evens
13-Apr-2007, 06:29
The Schneider f/8 90 mm Super Angulon is supposed to have an image circle of diameter 216 mm. That is more than enough to cover 4 x 5 with room for considerable movement. If the bellows is highly compressed, it is possilbe the standards are being forced to be out of alignment. If the image is centered and there is no rise or shift, then a tilt could produce a horizontal band in the center which is sharp but would go out towards the upper and bottom edges. Similarly, a swing would produce a vertical band which is sharp with the edges to either side blurred. A combination would produce a band making some angle with the horizontal which is in focus with the image going out of focus as you moved in a direction perpendicular to it. In all these cases the image would not go out of focus symmetrically as you moved away from the center, but there would be a central band in focus. If that is what you observe, with all four corners equally out of focus, most likely there is something seriously wrong with the lens.

Gene McCluney
13-Apr-2007, 07:24
I have a f/8 Super Angulon, in fact I have two, mounted for two different view cameras. Stopped down they are tack sharp right out to the edges. Possibly you do not have the lens elements seated in the shutter correctly? Are you shooting wide-open at f/8?

jokefloreal
14-Apr-2007, 07:31
Hey,
Thanxs for the reactions...........Monday I have my dia's, so I will see the results..I hope there is nothing with the lens..............
greets
Joke

jokefloreal
14-Apr-2007, 07:32
I schoot at F/32 or f/22 or f/16....

Alan Davenport
14-Apr-2007, 18:07
Any possibility that you have film flatness issues?