Hi to everybody:

I will appreciate if someone could give me a run down on what lenses are appropiate for a 12x20 large format camera. I am looking for a 450 or 480mm; 600mm and perhaps a 350mm.

I am interested in either new lenses or old lenses.

Also, I was wondering what is important to look for when shopping for a 12x20 lens, is it the image of the circle or the angle of coverage?

Best regards to all,

Alejandro

-- Alejandro Lopez de Haro (lopez_de_haro@compuserve.com), February 16, 2001

Answers

Ya might start here:

http://www.wisner.com/20x24lens.htm

-- Sean yates (yatescats@yahoo.com), February 16, 2001.

I think that the Nikkor 360W and Fuji 600C may offer sufficient coverage for this format. A reference for lenses covering 11x14 is here, and some of these will cover 12x20. This is a format I firmly intend to get into.

-- fw (finneganswake@altavista.net), February 16, 2001.

Don't mistake angle of coverage for angle of view.

If I'm not mistaken, the image circle is directly proportional to the angle of coverage --> if the image cirle covers the format, the angle of coverage will cover and visa-versa.

-- sheldon hambrick (sheldon_hambrick@hotmail.com), February 16, 2001.

Friend of mine have a couple of 25" f/9-256 Rodestock Apo-Ronar in barrel for sale.

-- Andres (andres@suurkuusk.com), February 16, 2001.

For modern lenses, Schneider G-Claron 355/9, when stopped down to f45, will cover 12x20 with an inch or so movements in each direction. You will be more confortable with new Fujinon 450 and 600. For old lenses, you might want to look at Dagors. A C. P. Goerz rectagon 270/10 will also cover 12x20. Write to Carl Weese for export advices.

-- Geoffrey Chen (DB45TEK@AOL.COM), February 16, 2001.

Hello Geoffrey:

Where do I find Carl Weese?

I prefer to be more confortable, so: How much movement would I have with the Fujinon 450? (Is this the same lens as: Fujinon CM-W 450?)

How about the Nikkor 450M, is it a suitable lens for a 12x20?

Regards,

Alejandro

-- Alejandro Lopez de Haro (lopez_de_haro@compuserve.com), February 16, 2001.

Carl is on the forum. Check some threads about ultra large format. That's his specialty. Maybe someone else knows his email address. Good luck!

-- Geoffrey Chen (DB45TEK@AOL.COM), February 16, 2001.

Alejandro,

Check here: http://home.earthlink.net/~cweese/

-- Geoffrey Chen (DB45TEK@AOL.COM), February 16, 2001.

Alejandro, One of the problems to deal with in 12X20 (besides equipment size and weight, and film cost) is finding lenses to cover the format. I measured a 12X20 holder - the diagonal is 23" or a little more, so you need at least that large an image circle. A larger circle is needed to have room for movements. Go to http://www.wisner.com/lenscov.htm and look at the column for 12X20. The numbers Mr. Wisner gives are degree of coverage needed in order for a particular focal length to be able to cover 12X20. Different lens designs have different degrees of coverage.Goerz Dagors (depending on vintage) have an 87 to 90 degree of coverage (one of the reasons Dagors are highly thought of by LF photographers). Reading down the column, a 305mm focal length is the shortest FL that will cover. In order to have room for movements, choosing a 14" (360mm) Dagor would be better. A 16 1/2" or 19" Dagor would give even more coverage, but as the focal length of Dagors increases, they become much more difficult to find (and more expensive). If you think you may want to someday move up to 16X20 format, you can use the longer Dagors. http://www.lensrepro.com/ is one source for older lenses like Dagors. The 450mm Nikkor (I believe) has a coverage angle of 60 degrees. By Mr. Wisner's chart, a 60 degree lens would need to have a FL of more than 480mm to cover 12X20, so it doesn't look likely the Nikkor will work. Goerz Artars cover about 45 to 47 degrees - hence the common 24" (600mm) Artar doesn't look like it should cover, although I've heard people claim it will. The next longer Artar shown in my Goerz catalog is a 30". Do you have enough bellows length? Protars covered a little less than Dagors - I believe a 14" or longer Protar would work, but I'm not that familiar with Protars. If you haven't already, look at all the Q&A part of Mr. Wisner's site, including the archive of older questions. Also http://hv.greenspun.com/bboard/q-and-a-fetch-msg.tcl?msg_id=004BTg and http://hv.greenspun.com/bboard/q-and-a-fetch-msg.tcl?msg_id=0004YH

-- Leonard Robertson (leonard@harrington-wa.com), February 17, 2001.

Hi, Alejandro - First off, I would start with one lens and see how it goes, then add others if the need arises. In my opinion - for many reasons - the banquet formats are at their best with wider lenses.

Regarding coverage, ignore those who say that, IN THEORY, this or that lens won't cover. Get it from the horse's mouth. Having said that, I can state that the 14" f/7.7 Goerz Dagor will cover the format with some (but not a lot) of movement. (And for most landscapes you won't need a lot of movement - just a little rear tilt for DOF, which doesn't eat up coverage.) Sharp, high contrast - I recommend it as a good "wide" 12x20 lens. Patrick Alt - who repairs these big cameras for a living and knows what he's talking about - says the Nikon 450M covers the format, and he recommends that lens. (There was a piece in View Camera by him about this a couple of years ago.)

The critical specification you are looking for is Image Circle, and in 12x20 the magic number is 585mm as an absolute minimum. Realize that most manufacturers list the circle of full illumination (i.e. NO mechanical vignetting) at f/16 or f/22, therefore these numbers are very conservative. You will usually shoot 12x20 at f/64, and will find many lenses that will cover even they are not "supposed" to. Listen to those with practical experience, or get the seller to give you a return privilage if the lens doesn't work for your format.

Good luck!

-- Mark Parsons (polar@thegrid.net), February 17, 2001.

Hi Alejandro, Try to look up this shop in Holland, they have a G-Claron 477/6,5 , don't know the price, I saw it today. You have to write them because they won't have it on the site. http://www.fotoabro.nl Good luck Andrea Milano

-- Andrea Milano (milandro@multiweb.nl), February 17, 2001.

Here ya go! Just what the Dr. ordered!

-- Sean yates (yatescats@yahoo.com), February 17, 2001.

D'oh! the URL didn't take!

http://cgi.ebay.com/aw-cgi/eBayISAPI.dll?ViewItem&item=1215556743

-- Sean yates (yatescats@yahoo.com), February 17, 2001.

So, what is everyone's guess on what this 19" Dagor will sell for?

-- Leonard Robertson (leonard@harrington-wa.com), February 17, 2001.

This isn't the shopping forum, but I have an absolutely mint Rodenstock Klimsch APO ROnar 800 mm in barrel for sale that will have no problem covering. Its big and heavy, but won't cost you even close to what those others will cost, and it will perform. kevin

-- Kevin Kolosky (kjkolosky@kjkolosky.com), February 17, 2001.

Mark Parsons refers to an article in "View Camera" where Patrick Alt recommends the 450mm Nikkor for 12X20. Mark (or anyone) can you look at the article and see if Mr. Alt goes into any detail on amount of coverage? Also, I agree with your point the "on paper" coverage may be less than what you get on film. If the upper corners of your image are sky, and the sharpness isn't perfect, will anyone notice? The great thing about newsgroups is having access to the real world experience of other people.

-- Leonard Robertson (leonard@harrington-wa.com), February 18, 2001.

In answer to your question about 19" Dagors, they sell for $1800- 2100, and are hard but not very hard to find. Expect to add some $ to put one into an Ilex #5 shutter, unless it already is or you don't mind using it in a barrel. I recently bought a 19" Dagor from

http://www.photomall.com/gelens.htm

This place, Glennview Camera, still has one more listed in their inventory, and seemed perfectly pleasant to deal with. I'm having SK Grimes put it in an Ilex 5, which I also bought from Glennview. Lens and Repro occasionally has these lenses, and just sold one, I believe.

Good luck,

Nathan

-- Nathan Congdon (ncongdon@jhmi.edu), February 20, 2001.