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Mark Sawyer
2-Jun-2005, 01:07
Okay, it wasn't exactly what I set out to do, but it happened. I bought a 300mm Astragon in a very nice Copal 3 for my 8x10 for $150. Not too bad, right? Here's the problem- it came with a partially finished 20x24 camera...

To make it all work, I'd need to build a back, a bed, and a couple of filmholders. It's a lot of work, but I can do that. But what to do for a lens?

This wouldn't be an everyday user camera, so I don't want to put a fortune into the lens, hopefully a couple hundred or less into an old barrel lens. Maybe a little more if I'm stupid...

I've searched all around the net, but Wisner's list (fairly short) of 20x24 lenses was about all there was. So, how `bout it? Anyone have any suggestions? (I'd like to stay under 600mm.)

My thoughts so far: a 600mm Tessar *should* cover, but I'm not sure. Sandy King said somewhere a 450mm Apo Nikkor will cover at f/45. Would that hold true for all the 450 Apo Nikkors? How `bout the 455 Apo Nikkor- it's rated at 770mm coverage, but is that at 1:1? Would the 21" Kodak Copy Lens work? What else should I consider? (The Dagors and Protars are out of my range, I'm sure...) Thanks, all!

Eirik Berger
2-Jun-2005, 04:19
I am in nearly the same situation. I have been searching for lenses to cover the 16x20" format for a while.
I have also visited the Wisner website, but more information is found here:

http://www.mamutphoto.com/ULF/lenses.html

There is also a user forum at this website, and all af the participants are very helpful. The other day one of them mailed me detailed photos of his homemade filmholder.
I dont know anything about your budget, but you will need a lens with an image circle above 800mm. I have seen Fujinon-A 600mm f11 on ebay not long time ago, which would be a suitable lens as it covers 840mm focused at infinity. This lens you can also use on your 8x10" camera of course.

Jim Galli
2-Jun-2005, 07:30
Mark, I think the least expensive good solution might be single elements of some old triple convertibles you're not even thinking of. There's a triple Voltas on Epay just now. The 28+" component of that lens should cover. And I think the 25" component of a Wolly Series 1 or 1a would likely cover. A single Protar VII element of 27" would also do it and be perfectly corrected. Any of the old Rapid Recilinear's that were designed for 8X10 and larger can be used single element and most would be long enough to cover I think. You'd have some "personality" at the corners with most of these. I've got an ancient Protar Series IV wide field lens that is rated for 16X20 that would cover easily. Contact me offline if interested...but it isn't inexpensive.

Donald Brewster
2-Jun-2005, 10:08
16.5" Dagor or 30" Artar would work -- you can probably find them in barrell. I think Tracy Storer uses a Fujinon 600C on the big Polaroid. Maybe Tracy or Sandy will chime in here.

sanking
2-Jun-2005, 10:10
I have my doubts that the single elements of double or triple convertible lenses in the 25" to 28" range will cover 20X24'. My own experience is that the single element 25" component of the Wollensack triple convertible, which is similar in design to a Protar VII, will not cover even 7X17" without significant loss of performance on the edges. Same is true of the single element of the 300mm and 360mm convertible Symmar. The coverage of the single elements is no more than about 45 degrees, if that, so you would need a very, very long single element to cover 20X24.

Best bet in my opinion for inexpensive lenses for the 20X24 format would be process lenses in the 24" and longer range. The 24" lens would just cover (stopped down a whole lot) , while anything longer than 30" would cover fine.

In modern lenses the 450mm Nikkor-M and 600mm Fujinon-C both cover 20X24, but you will need to stop down a lot for good performance on the corners. A 19" Dagor would also do nicely, but these are fairly rare and quite pricey.

Mark Sawyer
2-Jun-2005, 12:01
Eirik- thanks for the link! I'd found the Mamut site, but not the lens page. It's actually very good info for even an 8x10 user. Would it be difficult to forward the filmholder pictures to me at marksawyer@access4less.net? I'd love a Fujinon 600mm, A or C, but doubt my budget would handle it...

Jim- I have an old Turner Reich 12/21/28" (I think) convertible. I was thinking of trying the 28" element, but I've been somewhat disappointed in the single cells of the convertibles I've played with in the past. But I suspect I won't be enlarging these, so maybe... I could also just try single cells of other 12" or longer lenses. Your Protar is probably out of my price range, but thanks for the offer!

Donald- Though I'd love one, the Dagor, even in a barrel, will be out of my range, I'm sure. Too bad; a 16.5" or 19" lens would be about right. The 30" Artar would be too long for my work.

Sandy- Any idea if a process Nikkor (450/455/480/600mm) would cover? They seem more available and less expensive than the 450-M. I usually stop way down, so that's not an issue. In photos I've seen of them, the Nikkors (and 21" Copy Ektar) seem to have a much shorter barrel than my 480mm Apo Ronar, so they should have wider coverage. (I know the Ronar won't cover 20x24...)

Thanks again, all! Good info on an area I'm unfamiliar with...

Dan Fromm
2-Jun-2005, 12:27
Mark, I think you mean Apo-Nikkor. Process Nikkor isa name, not a type, and the longest one is, IIRC, 260 mm.

Apo Nikkors are relatively narrow angle lenses, per Nikon won't cover their focal lengths at infinity. In the documentation I've seen on them, the image circles are for 1:1 and give a false impression of how useful the lenses are.

Perhaps we should all chip in to equip you and Calamity Jane with genuine Larger Format Than Originally Intended begging bowls.

Cheers,

Dan

Struan Gray
2-Jun-2005, 12:42
600 and even 800 APO-Ronars have gone for surprisingly low prices on eBay.de and ebay.fr recently, and the APO-tessars from Zeiss Jena are well in your price range. They'll be 'normal', but very high quality.

sanking
2-Jun-2005, 13:44
Sandy- Any idea if a process Nikkor (450/455/480/600mm) would cover? They seem more available and less expensive than the 450-M. I usually stop way down, so that's not an issue. In photos I've seen of them, the Nikkors (and 21" Copy Ektar) seem to have a much shorter barrel than my 480mm Apo Ronar, so they should have wider coverage. (I know the Ronar won't cover 20x24...)

You will need at least a 600mm Apo Nikkor to cover 20X24", and that is pushing the issue because even stopped down this lens will be veryh soft on the corners. The 480 Apo Nikkor won't make cut the mustard, even when stopped down, though the actual circle of illumination might just make it.

Mark Sawyer
2-Jun-2005, 15:27
Struan- Ronars are a Dialyte (sp?) design that has I think only about 43 degrees of coverage; the 600 gets 496mm at f/22, so I dout even the 8oo would make it.

Dan- thanks for the corrections, I'm sure I'm making mistakes here, and you're all helping me figure them out! I'm considering this thread my "begging bowl" for information...

Sandy- Guess the Apo Nikkors are out. Thanks, and by the way, as I research this, posts that you, Jim Galli, and others made years ago are still providing great information. Double-thanks!

Tracy Storer
2-Jun-2005, 19:10
Not long ago I practically gave away a 19.75" Eastman Anastigmat on Ebay. It covered 20x24. (admittedly, not the best at the edges, but still...) It wasn't one of THE lenses, so nobody seemed to care. The Fuji 600 C is as good as it gets and as new lenses go, it isn't THAT expensive if you want to shoot "big". My experience with single cells of shorter convertibles hasn't been that rewarding.(some cover, but with BAD edges) I tried a 600 Apo Ronar once, and wasn't satisfied with the edge performance near infinity(IIRC), but I had an 800 Apo Ronar, it covered fine and was one of the sharpest lenses I've ever owned, but at f/9 it weighed 8 pounds.

Struan Gray
3-Jun-2005, 02:18
Dialyte process lenses are specced for their intended application, which demands high resolution and low distortion over the whole field. The image does go to hell faster at the limits of the stated circle than with plasmats and tessars, and it doesn't improve so much with stopping down, but you can still squeeze a bit more out dialytes if you're not enlarging I have an 18" APO-Lustrar dialyte that covers 12x15 wll enough for contacts, despite being well outside its official image circle. Older lenses are more versatile for this as they tend not to have agressive field stops.

The APO-tessars are, well, tessars. I would expcet a 600 APO-tessar to cover 20x24, but perhaps someone here can confirm it.

The real problem is, as Tracy said, weight and bulk. APO-Lustrars are nice in that they often have slightly smaller apertures than more well-known lenses, and switched to aluminium barrels early on. The long ones are f16, but don't turn up very often.

Mark Sawyer
3-Jun-2005, 16:44
Tracy- I've had the same experience as you with the convertibles; the only one that was acceptable was the 14" (converted from 8 1/2") Acuton/Caltar, which looked "okay" on 8x10 contacts. The aperture can't be in the right place (all in front of the glass) on a converted lens.

Do you (or anyone else) know if the 21" and 22" Kodak copy lenses are the same design as the 19.75"? These seem like they'd be nice lenses, not too expensive, and come around once in a while...

Struan- I'd like to know the coverage on the 600mm tessars, too. I've seen several statements that Zeiss Apo-Tessars cover 20x24, but Zeiss made several (many?) different 600mm Tessars, and there are other 600mm Tessars out there too. (I lost a 600mm Russian Tessar to a snipe-bidder a few days ago...) Probably some do, some don't...

Tracy Storer
3-Jun-2005, 18:12
I don't know about the Kodak Copy lenses, maybe someone else does and will post. Not to state the obvious, but unless you're shooting near infinity a lot, you'll be able to get by with some very common and more affordable lenses, since coverage quickly increases as you focus on closer subjects.

Mark Sawyer
3-Jun-2005, 19:03
It would frequently be a landscape lens, so yep, it needs to cover at infinity.

Actually, I've tracked down two possibilities in my price range: a 530mm f/10 Cooke Apo Process Series IX, and a Kodak Ektanon 530mm f/11. Anybody know whether these would cover? The Mamut photo site lists the Ektanon as having 592mm of coverage, (20x24 needs 800mm). But it lists the Fujinon 600-C as having 486mm of coverage, and the Nikkor 450 M as having 440mm of coverage, and we've got first-hand knowledge here that they both cover when stopped down.

Eric Leppanen
6-Jun-2005, 15:53
Mark,

The Fuji 600C is actually rated at 620mm of coverage: www.thalmann.com/largeformat/c.htm (http://www.thalmann.com/largeformat/c.htm)

Of all the modern lens manufacturers Nikon is generally by far the most conservative regarding image circle ratings. I'd be careful when extrapolating Nikon ratings to other lens manufacturers and designs.

Mark Sawyer
6-Jun-2005, 16:59
Thanks for the info, Eric. About all I can extrapolate from figures I've seen so far is that coverage numbers from different sources don't agree with each other or with what a specific example of a lens actually does. I don't think any of these lenses were meant for 20x24, but cover sort of "by accident." The best info is from people who have actually used a lens on 20x24, but that's pretty rare.

Anybody know what the coverage is for 600mm Aero Ektars and Aero Tessars? I've been seeing a few of these around fairly cheap lately...

Ole Tjugen
7-Jun-2005, 01:15
APO-Tessars generally have less coverage than "regular" Tessars, 40 to 45 degrees according to my 1910 literature. This may be due to stricter tolerances, after all nobody in their right mind would use one for general shooting in 1910 - at a price of 10 to 100 times that of a perfectly good anastigmat!

A propos aero lenses: Anyone know anything about Schneider Aerotar's? I just won 7521056507 on ebay...

Dan Fromm
7-Jun-2005, 05:20
Ole, when you have y'r Aerotar in hand, tell us about it. It is pretty much a mystery lens AFAIK. As in, they're around but there's no easily-found information about 'em. They seem to have been made between the wars.

Mark, the Vade Mecum says they were used on 9x18 cameras. That's inches, not cm, and the cameras used 10" roll film. The VM adds that the AeroEktar and AeroTessar were made to the same specification.

John D Gerndt
7-Jun-2005, 15:03
I have a 530mm f11 Copying Ektanon and 24 inches of image is all you'll get out of that. The older anstigmats are rumored to have better coverage but I have not tried one.

Remember that the Dagors were copied a lot, you could look for one, though I don't know how many were copied in 19 inch form...

Cheers,

John

Mark Sawyer
7-Jun-2005, 18:02
Ole- Apo-Tessars out, regular and Aero, maybe... Thank you!

John- Thanks, you just saved me $150; I was thinking of ordering the 530mm Ektanon.

Dan- Yes, I've heard the Aero Tessars/Ektars were made for 9x9 and 9x18, but then the Nikkor-M 450mm is for 8x10 with a rated coverage of 440mm. I may end up springing for the Nikkor or Fujinon, but I'll grumble about it for years...