PDA

View Full Version : Soft 90mm Grandagon



Dan Baumbach
15-Mar-2005, 10:39
I have a used 90mm Grandagon f/6.8 that I purchased a couple of years ago. The lens is multi coated and the glass looks very clean. Everything I've read on this lens says it should be very sharp but it doesn't compare to my 75mm Nikkor or 58mm SA. Could something be wrong with the lens mounting or could there be something else that is causing this lens to be less than it should be and can it be fixed?

Leonard Evens
15-Mar-2005, 11:36
I have that lens, and it is sharp. It is certainly possible there is something wrong with it. Perhaps it is not mounted properly in its lensboard. Or for some reason, you may not be focusing properly with it.

Donald Hutton
15-Mar-2005, 11:55
Not sure about that particular lens, but a lot of wide angle lenses have shims which correctly space the rear element from the front (sometimes these are in a separate space; sometimes they are against the rear element when you unscrew it). These could be missing. Also, the lens could be suffering damage which has caused some part of the optical assembly to go out of alignment. This is possible through dropping a lens which does not always result in visible physical damage. It's very unlikely that it could be such a "bad sample" of a particular lens. Sharpness should be at least on a par with the other two lenses you mention.

Sam Crater
15-Mar-2005, 12:33
Is any part ot the image sharp?

J. P. Mose
15-Mar-2005, 13:32
I have read other threads stating what Don has said. Assure that the rear section of the lens is properly aligned with the front. Perhaps Marflex can examine it on a collminator as they are the authorized repair depot in the USA (assuming your lens is not grey market!!!!!!!!!!!!!).

Armin Seeholzer
15-Mar-2005, 15:28
And if it is greymarket then send it to Linos ( Rodenstock ) in germany directly and they tell you whats wrong:
Good luck!

Andy Eads
15-Mar-2005, 16:40
Give the lens a gentle shake to hear or feel if a lens element has come loose. I have a Caltar 90mm Wide Field that loosened up ever so slightly resulting in sof t focus negatives. Fortunately, it was just the rear element which only required that the retaining ring be tightened. I hope yours is that simple.

Dan Baumbach
16-Mar-2005, 09:04
Nothing's loose. The lens just doesn't have that contrast and detail of my other lenses. How do I contact Marflex?

- Dan