John Ackley
Subscriber
Has anyone had experience with the Vintage Schneider-Kruesnach 90mm f/6.8 Angulon Lens? I am interested in vignetting details.
Its a very common lens. I've ended up with 3 of them, but I don't use them very often. They barely cover 4x5, but I don't remember a pronounced vigniette in any of my occasional use. I've always understood vigniette to be a function of the difference between distance from the lens to the center of the file and the distance to the corners of the film (inverse square law), and 90mm on 4x5 didn't have enough of a distance to haver a pronounced vignette.
When the image circle is too small to cover the corners of the film, that's vignetting too; complete non-exposure in the corners. It's not mechanical vignetting either, just a too-small image circle.
You'll run into this with the 90mm f/6.8 if you use much in the way of movements. A few mm of rise will vignette the top corners, etc.
Doremus
When the image circle is too small to cover the corners of the film, that's vignetting too; complete non-exposure in the corners. It's not mechanical vignetting either, just a too-small image circle.
You'll run into this with the 90mm f/6.8 if you use much in the way of movements. A few mm of rise will vignette the top corners, etc.
Doremus
I looked it up, out of curiosity, and inverse square may only be part of the effect, which is commonly referred to as cos^4. Its also because at extreme angles the shape of the entrance pupil makes it have smaller area (oval vs circle), and some other effects.
There is also mechanical vignetting, but that isn't usually relevat to what I think you're asking about. Its just a hard blick in the lens or shutter si the uncorrected parts of the image circle get blocked. This creates a reletively hard line where the image circle ends and is not a aesthetic vigniette.
I use the Angulon 90/6.8 on my DIY 6x12 panoramic camera, and there is good coverage and edge sharpness. Since I use the 6x12 camera for landscape, I always stop down to f/16. Mine is a later version in black Copal shutter, and is quite lightweight and compact in addition to be excellent optically.
I have never used the 90/6.8 on 4x5 though, since I already have a SA 90/8 with larger coverage.
When the image circle is too small to cover the corners of the film, that's vignetting too; complete non-exposure in the corners. It's not mechanical vignetting either, just a too-small image circle.
You'll run into this with the 90mm f/6.8 if you use much in the way of movements. A few mm of rise will vignette the top corners, etc.
Doremus
I've also got 3 of these because they are small, light and inexpensive as said above. Nearly no movements in 4x5" and 9x12cm. I use them for 6x12cm panoramic, an old 9x12 Linhof and for DIY Instax Wide cameras.
they are all in the same Compur Rapid, with no preview.
I have a vintage version of this lens, the cells are in black barrels, very slightly better coverage than the later post-WWII version in terms of vignetting.
Be aware there were quality issues with early ones after the war, they are all in the same Compur Rapid, with no preview. Linhof introduced their Select system because of inconsistent sharpness.
The late Dean Jones, who made Razzledog Polaroid conversions realised the issue was not the lens elements rather poor finishing of the shutters, and out of tolerance shutter barrels. He was a camera repairman and machined unsharp 90mm Angulon shutter barrels to the correct specification, and then the lenses were sharp. Before his untimely death Dean was asking user to measure the barrel lengths of their lenses.
I bought a90mm f6.8 Angulon in the mid to late 1980s an it was awful, I borrowed another, it was little better. Then I struck lucky about 20 years ago, and found a sharp one, which I used for hand-held work, an excellent performer. I only sold after getting offered a very late 1969 90mm f6.8 Angulon in a much newer Compur shutter, with a preview lever, at a trade price.
It's long been accepted that the sharpness issue had been resolved by SN 5,000,000, older some are excellent others are poor.
Ian
My 90mm 6.8 proved to be a good one. I used it a lot during the pandemic, when I took a number of short road trips through the Mississippi Delta. Serial 888xxxx, Synchro-Compur shutter. Carol Flutot cleaned/adjusted the shutter for me. I had bought it on the 'Bay, and the seller was not honest about the shutter speeds. The photo below is from the town of D'Lo.
View attachment 424666
I dunno if my angulon is a bad copy but it's basically gathering dust since I picked up a wide field ektar on a whim. What a wonderful lens that is.An alternative to the Schneider Angulon 90mm f/6.8 that is about the same focal length, but with a larger image circle is the Wide Field Ektar 100mm f/6.3. It's as lightweight too.
| Photrio.com contains affiliate links to products. We may receive a commission for purchases made through these links. To read our full affiliate disclosure statement please click Here. |
PHOTRIO PARTNERS EQUALLY FUNDING OUR COMMUNITY: ![]() |
