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F64
18-Sep-2015, 12:31
Hello,
I just got it on a funny smallish board. I tried to use it on a Sinar just by holding the lens on the board in front of the Sinar board hole. I am not able to focus on objects 2 mt away. I am using wideangle bellows, and the two standards are about 2cm away.
What am I doing wrong?
Thanks

MDR
18-Sep-2015, 12:52
The lens at infinity focus would be a distance of around 8cm between the Standards, focussing closer you would have to pull the Standards even further apart. 2cm apart is nearly 4 time infinity.

F64
18-Sep-2015, 13:02
That's what I thought. Some additional space, say 1 cm, is taken by placing the board in front of the Sinar board. Still, I don't understand what's happening

Dan Fromm
18-Sep-2015, 18:35
Hmm. 80 mm focal length. Total extension ~ 30 mm. Minimum extension needed to focus at infinity ~ 80 mm. Extension needed to focus closer than infinity > 80 mm.

What am I missing?

Michael E
19-Sep-2015, 07:52
Obviously, if the camera is completely compressed, it is not focused at 2m. But it is not an obstacle either, focus at 2m can be achieved by extending the bellows. My Weitwinkel Aristostigmat 8cm/f6.3 is focused at infinity with the rear lens 75mm from the ground glass, focused at 2m with a distance of 77mm. No scientific data, just a quick measure on my camera. It you can't focus the lens, there might be something wrong with it: Missing, interchanged or simply reversed elements, wrong spacing due to a wrong barrel or shutter, etc... Good luck!

By the way, my lens just illuminates 4x5" with no wiggle room.

Michael

F64
19-Sep-2015, 10:19
It you can't focus the lens, there might be something wrong with it: Missing, interchanged or simply reversed elements, wrong spacing due to a wrong barrel or shutter, etc... Good luck!


That looks like it. I know that extension should be roughly >=80mm. The problem is that it isn't with this lens. I'll try to post some photos of the lens.

F64
19-Sep-2015, 11:13
Here a couple awful photos. The rear has a thread, but the lens is actually much further down (hope it shows)

http://www.albertomantelli.it/lf/_DSC9725.jpg

http://www.albertomantelli.it/lf/_DSC9724.jpg

http://www.albertomantelli.it/lf/_DSC97231.jpg

Michael E
20-Sep-2015, 02:35
Oh, yours is a f9? Mine is a f6.3, so this might not apply. I have attached two photos: My rear lens assembly is not recessed. The overall length of my lens is 24mm.

MDR
20-Sep-2015, 02:39
If I remember correctly the WW-Aristostigmat is a symmetrical or near symmetrical lens. So you should be able to use them as convertible lenses, try to focus with only the rear group and with only the front group if there is a big difference in bellow draw the lens has probably been wrongly assembled. Good luck,

IanG
20-Sep-2015, 02:55
I was going to say check the two serial numbers are the same my f9 5" (130mm) has identical serial numbers on front and rear cells, but your rear cell appears to have no number. Mines slightly oled SN 427***.

The 80mm covers Quarter plate according to Meyer adverts.

Ian

F64
20-Sep-2015, 12:37
Thanks, everybody.
@Michael E: The rear assembly is more recessed than yours but not very different. Length is approx 24mm as well.
@MDR: I will try to check front and rear, but the front lens does not seem to unscrew easily
@IanG: I was hoping for a bit more. I figure it will look more or less like my 100mm Staeble. Luckily it was not very expensive.

IanG
20-Sep-2015, 16:18
@IanG: I was hoping for a bit more. I figure it will look more or less like my 100mm Staeble. Luckily it was not very expensive.

I'll check my BJP Almancs for the 1920's 30's, I think one set of adverts lists two columns for coverage with these lens which are supposed to have 100 coverage wide open (f9). They are similar to the early Angulons which have a touch more coverage than the later post war versions (chrome front cell mount barrel) which run out of coverage because they vignette once you use anything more than very slight rise/fall.

Ian

F64
21-Sep-2015, 00:06
I'll check my BJP Almancs for the 1920's 30's

Ian
That's very kind of you, but I hate to waste your time. My primary concern is to make it work: I can return the lens and that's probably what I will do.

Steven Tribe
21-Sep-2015, 01:27
The only contribution I can make is that I doubt the WA aristostigmat was originally mounted in this vario shutter.

The Vario was a very basic shutter for budget 6x9 and 9x12cm folders - typically without extensions and with an aplanat. The aristostigmat is a lens that the more adventurous mounted on more advanced cameras. Failure rate of the early dial shutters may have lead to it being mounted on a shutter with too great a distance between threads. A few of the early wide angles did no have enough clearance to be mounted in any shutter successfully.

IanG
21-Sep-2015, 02:58
You're right Steven, Meyer sold these lenses in a Compur shutter or barrel, it's the aperture scale on the Vario seems correct. So maybe some were sold in Vario shutters.

Ian

MDR
21-Sep-2015, 03:01
The only contribution I can make is that I doubt the WA aristostigmat was originally mounted in this vario shutter.

The Vario was a very basic shutter for budget 6x9 and 9x12cm folders - typically without extensions and with an aplanat. The aristostigmat is a lens that the more adventurous mounted on more advanced cameras. Failure rate of the early dial shutters may have lead to it being mounted on a shutter with too great a distance between threads. A few of the early wide angles did no have enough clearance to be mounted in any shutter successfully.

The Vario was offered as an Option it is indeed the original shutter you could buy it as a Barrel Lens, mounted in a Vario shutter, in an Ibsor shutter or in a Compur shutter.

F64
21-Sep-2015, 09:29
Thanks again, everybody. Methinks I'll return the lens.