20x24 lenses

[Mark Sawyer]

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]

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]

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]

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]

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]

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]

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]

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]

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]

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!