Wollensak 15" f/5.6 Raptar Telephoto

[Randy]

Al, I just mounted mine on a lens board and put it on my 8X10 and it will not cover the format at infinity (I just look through the cut-out corners of the ground glass and can't see through the lens from the corners). Wonder if they made different versions. I have a 5X7 back that I plan on using it with.

How can you tell the different sizes of the Alphax shutters? I am watching a few on ebay but there is no size indicated, so I don't know what they are. I guess I could ask the seller for measurements.

[Kevin Crisp]

I've had two and use them often on 5X7. There is room for movement. Both I've had have been mounted in Alphax shutters, which are quite a decent vintage shutter and quite trouble-free. Alphax shutters are often available as bargains.

As others have commented, its performance is outstanding and I've never understood why they are seemingly so under appreciated. Great value. And being a true telephoto design it can be the answer for many people who want a long lens but don't have the 4X5 bellows for it.

I believe there is an Alphax shutter these will screw directly into as well

[E. von Hoegh]

I've had two and use them often on 5X7. There is room for movement. Both I've had have been mounted in Alphax shutters, which are quite a decent vintage shutter and quite trouble-free. Alphax shutters are often available as bargains.

As others have commented, its performance is outstanding and I've never understood why they are seemingly so under appreciated. Great value. And being a true telephoto design it can be the answer for many people who want a long lens but don't have the 4X5 bellows for it.

I believe there is an Alphax shutter these will screw directly into as well

Wollensak lenses in general seem to be under appreciated. I've had several of various vintages, they were all very good and most were excellent. I still use an Enlarging Velostigmat for 6x7.

[al olson]

Al, I just mounted mine on a lens board and put it on my 8X10 and it will not cover the format at infinity (I just look through the cut-out corners of the ground glass and can't see through the lens from the corners). Wonder if they made different versions. I have a 5X7 back that I plan on using it with.

Randy, you are right that there is some darkening in the corners. The first image below was focused at infinity and it shows a little darkening in the upper right corner.




The second image below (taken some years ago from my home in Virginia) was focused to a distance of about 150 feet from my deck. With a little experimentation today from my window, I find that the difference between the mountain ridge and my neighbor's house (approximately 150 feet away) in focus distance to the film plane is about 2 mm. Two out of 380 mm is about 1/2 of a percent.



Using a small aperture and focusing at the hyperfocal distance should allow the entire 8x10 to be covered. Doesn't leave much room for movements, but I seldom print the entire negative anyway.

How can you tell the different sizes of the Alphax shutters? I am watching a few on ebay but there is no size indicated, so I don't know what they are. I guess I could ask the seller for measurements.

Can't help you there. Like I said, I thought my Alphax was a #5, but on examination there are no markings to indicate its size. This may be why the sizes are not being specified on ebay. The lens is huge and likewise the shutter is also large, but I have no idea how large a #4 would be in comparison.

[Leonard Robertson]

The chart on this page gives some dimensions for Alphax shutters: http://lensn2shutter.com/shutters.html
Ilex Acme shutters in the larger sizes have different fastest speed for the different sizes. A #4 Acme has a top speed of 1/150, while a #5 Acme only goes to 1/50. I don't know if that is true for Alphax shutters. Usually you can see the top speed in eBay pictures. I believe I only have one or two Alphax shutters, but I'll look at the top speed.

Len

[al olson]

If this is also the case with Alphax, the top speed of 1/50 suggests that my shutter is a #5.

The shutter prices in that article seem extremely high even in today's market.

[Randy]

Al, the chart indicates that the #4 shutter has a thread diameter of 62mm, which is the thread diameter of the lens (I measured it last night). So, looks like your's is a #4. I am looking for an Alphax or Betax #4. Otherwise, I am going to have to fashion my spare Packard shutter in front of the lens. Don't really want to do that, but I am anxious to play with it.

[al olson]

Randy, thanks for the information. I had to take a look, unscrewed the lens, and put the calipers to it. You're right about the thread diameter, I got a reading of about 61.41mm. If this is a #4, then you should expect that the Alphax #4 has a maximum shutter speed of 1/50. Do the Betax #4s go to faster shutter speeds?

I also have a 10" Raptar. Its shutter is a Grafax (made for Graflex by Wollensak), mounted on a Super Graphic board with a 1/200 maximum shutter speed. I am guessing that this is a #3, but would it be equivalent to an Alphax or a Betax?

[Kevin Crisp]

Betax shutters don't go faster than anybody. But since I don't think I've ever used a shutter speed faster than 1/30th in LF, no problem for me. They just seem to be very reliable and the self cocking is convenient.

[winterclock]

I got mine in barrel, it screws right in to my alphax #4. The #4 only goes to 1/50th, if you can find one from a 12" normal lens the aperture scale will be correct.
If you do this watch out for the set screws in the lens barrel, there is one hiding under the aperture ring.