Wollensak 21.25 inch f10 Apochromatic Raptar

[iangreenhalgh1]

Hi folks

I spotted this unusual huge lens on ebay and as there were no bidders I decided to grab it, cost 10ukp plus 15 shipping.

[Seele]

This is a process lens for making colour separations from original artwork, this explains it being apochromatic, marked with precise focal length, and the reversing prism.

[Scheimpflug]

Wow, that is a beast!

How much does it weigh, now that it is out of the frame?

You're building up quite a backlog of huge lenses to test.

[iangreenhalgh1]

Thanks Seele.

I haven't taken it out of the frame yet, i will do so and weigh it, I think it's at least 800g, maybe a kilo.

Anyone got any idea if it will work as a camera lens if mounted on a long enough tube?

[Scheimpflug]

[martinsmith99]

Now you see why you were the only bidder.

[iangreenhalgh1]

Thanks for the tips, that Vivitar is a beast!

I actually have a 8/500 sat here that I will never use again, low IQ cheap tube type, I was thinking I could use that to remount the Raptar.

It will be a challenge to get it working but I like a challenge!

[iangreenhalgh1]

Well, I finally got the lens out of the mount/prism. I had to drill out the three retaining grub screws that held on a square metal plate, the Raptar is actually quite small and light for what it is.

I removed the glass from that cheapo 8/500 and stuck the Raptar in the end, just held in place with some gaffer tape for the time being.

It's not long enough, I'm guessing the lens needs to be 541.2mm from the sensor, making this mount a good 6 inches too short...

Back to the drawing board to figure out the best way to extend it!

This is going to be a cumbersome beast, let's just hope when it's done, the IQ will prove good enough to have been worth the hassle!

Large format users are very fond of these Apo-Raptars, despite them not being optimised for infinity so I have hopes it will be a good performer.

[iangreenhalgh1]

Well, I had a eureka moment and decided to strap a set of M42 bellows on the back of the modified 500mm tube and I was correct, the tube was too short.

This is a terrible shot but best I could manage in the brief time I had (about to go to work) and it does prove that this lens will work.



So now I need to complete the work of moutning this beast permanently, I will then try it out on some better subjects. I don't see any CA, which is a good thing, guess that's to be expected with an apochromatic lens?

I did find a diagram of the Apo-Raptar's optical scheme but precious little else in the way of info:

[Willem]

Love this sort of project!

[iangreenhalgh1]

Thanks Willem, I hope to have more time to fiddle with this contraption soon and show you some pics of the beast itself, however, I don't have a day off this week so might not be till next week.

[Scheimpflug]

Any updates?

[iangreenhalgh1]

Not quite, the lens is remounted and ready to rock, but been working too much overtime and weather been too bad, will try it asap.

[iangreenhalgh1]

Well, I finally got an opportunity to try this lens out.

I'm impressed with it, sharp and no CA. These were wide open at f10.



100% crop:



Stitched Panorama:



100% crop:



Another stitched image:

[Lloydy]

That's impressive Ian.

[iangreenhalgh1]

Cheers, now I'm on the lookout for a 36inch version!

[Lloydy]

Will Millom be getting a demonic camera obscura then ?

[iangreenhalgh1]

Hehe, no but it will be seeing me dragging around a 3 foot length of drainpipe attached to a camera...

[ManualFocus-G]

The lack of CA is brilliant! Not sure how convenient it is as a walkaround lens though

[luisalegria]

Brilliant shot !

[iangreenhalgh1]

The apochromatic tag really does apply here, which is very pleasing, I now want to collect more apochromatic process lenses.

Not a chance of handhold this thing, and it was a challenge shooting it on my rickety old tripod, I'm very surprised I didn't have a problem with camera shake. I forget what shutter speeds I used now, but I did turn the ISO up (6400 I think) hence the graininess. I wouldn't need to use such high ISo in better light, it was getting dark when I took these pics.

For 25 quid plus about a tenner for the 8/500 crap lens I cannibalized I think this is a bit of a bargain, an apochromatic extreme telephoto is rather more expensive. Only cheapo apo tele I can think of is the Sigma 400mm and that is a very unreliable lens judging by how many faulty ones turn up on ebay. I doubt AF would be very useful with such a long lens and f10 is fast enough with the good high ISO performance of my NEX so all in all, I don't feel I'm missing out on much by using this in lieu of a very expensive long apo lens.

Just out of interest, how much would a 500-600mm apochromatic telephoto cost me these days?

[iangreenhalgh1]

[Kathmandu]

Looks like an interesting lens.

[danfromm]

Ian, dialyte type process lenses -- that's what your Apo Raptar is -- are well known in the on-line large format community. Although usually optimized for 1:1, they hold their corrections very well at all distances.

Goerz (at the very end, Schneider) Apo Artar; Schneider Repro-Claron; most Rodenstock Apo-Ronars; some, not all, Apo Nikkors (there are also Tessar type Apo Nikkors); and Wray Apo Lustrar are all dialyte type process lenses. Reports on all but Apo Lustrars are very positive. At one time Rodenstock propaganda asserted that long Apo Ronars performed better than any large format telephoto lenses. This is no longer true, modern LF teles are better but much more expensive.

There are also Tessar type process lenses. Reports on CZJ Apo-Tessars, Industar-11 M (one name, many focal lengths), and TTH Apotals (also TTH and Cooke badged "Copying Lens") are all very good. I have one each Apotal, Cooke Copying Lens, TTH Copying Lens; all are very good.

Heliar types? Voigtlaender Apo Skopar, Boyer Apo Saphir. I'm a fan of Apo Saphirs but dialyte type Apo Nikkors are better at apertures larger than f/16. Lighter, too.

More complex? Konica Hexanon GRII, not all the same design. Very sharp, a little flary. CZJ/Docter Apo Germinar. Rodenstock Apo Gerogon. LOMO RF-2, -3, -4, -5. Schneider G-Claron. All well regarded. Some of the longer Apo Ronars have > 4 elements; all get good reports.

Questionable? Nikon Process Nikkor. WA G-Claron. It seems that (relatively) wide angle 4/4 double Gauss types optimized for 1:1 don't hold their corrections well at distance.

Beware, some of these lenses are very heavy. In particular, longer Klimsch Apo-Ronars (my 600/9 weighed 3.3 kg) and Apo Saphirs (my 900/10 weighs a little over 4 kg)

With most of these lenses, central image sharpness is better around 1 stop down from wide open, declines after that. Stopping down farther improves edge sharpness; not a benefit for small chip digital cameras or even medium format film cameras like my 2x3ers.

[iangreenhalgh1]

Thanks for that info Dan, I have my eye on a 47.5 inch red dot Artar...

I have found that wide open, the sharpness of this Raptar is merely good, down two stops to f22 and it's very sharp. Contrast is low but easy to fix in Photoshop, I need to make a hood for it, it has no threads so I will adapt a rubber sink plunger as I have with some other odd lenses.

This is how I am using it atm, on a rickety old tripod with a set of bellows on the back to enable focusing. There is a helicoid in the stripped 500mm lens but the tube needs extending about 6 inches, so until I add more tube I'm using the bellows to get the required extension and I really like the ease of focus the bellows gives.

I removed the glass and aperture blades from that crappy Hanimex 8/500 long lens and stuck the Raptar in the front, crude but it does the job.