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Padraig O'Blivion
17-Oct-2000, 14:16
ok, I need help. Can someone explain to me the difference in large format lenses??? How many kinds are there? The mounting-how is it done???? Are the shutters alw ays seperate? How does one set the exposure speed? Also, I keep seeing pictures of 4x5 backs that seem to have another frame over the groundglass, this thing h as two tabs on the left side. What is this for??? Mine doesnt have one. Is it just another variation of a back??? thanks a million in advance

P. O'B.

Ellis Vener
17-Oct-2000, 20:47
"Can someone explain to me the difference in large format lenses???

Yes.

" How many kinds are there?"

twelve.

"The mounting-how is it done????"

Have you ever read The Joy of Sex?

" Are the shutters always seperate?"

Only since the divorce.

" How does one set the exposure speed?"

Swiftly.

Doug Paramore
17-Oct-2000, 21:26
If I can quit laughing over Ellis' answer long enough I will try to help. In all sincerety, you need to spend some time in a well equipped library. There are numerous formulas for LF lenses, the current favorite by manufacturers being the plasmat formula. There are many, many lenses based on the Tessar formula, which are four element lenses. If you go back to the turn of the century, you will discover a large array of lenses and formulas. Most modern lenses are mounted in shutters, but that was not always the case. Many were sold as barrel mounts to be used with the Packard and other behind the lens shutters. There were even 4x5 focal plane shutters. The lenses have to be mounted on a lens board, which then fits onto the camera. The exposure is set through the shutter and the aperature, just like 35mm. I hope this was a serious question you posted. If not, I'll feel like a fool.

Regards,

Pete Andrews
18-Oct-2000, 08:48
Padraig. You obviously need a very gentle introduction to large format photography. It's going to be far too much to take in at one go.I suggest you take yourself down to the nearest hardware store and buy yourself a file. Take the file and open up the little hole in the back of your 35mm camera where the film goes, just a little bit at first, maybe half a millimetre all round.Take some pictures with your new larger format camera, and see how you get on. When you feel comfortable with it, open up the gate (that's the technical name for the film hole) a bit more.Keep doing this until your pictures have funny oval holes all along the edges of them, then throw your camera away.Move on to something a bit bigger, like a Hasselblad with a 645 back, and then do the same thing with that. Eventually, you'll be experienced enough to handle a 'real' large format camera.That's the way we all did it (honest).

Erik Ryberg
18-Oct-2000, 09:34
When I first contemplated buying a large format camera my only information came from Shutterbug and I lived in a rural area in Idaho with no access to LF information. The matter of lenses was very confusing.

Generally speaking, any LF lens will fit any LF camera as long as the lens board is big enough and you have enough bellows draw. Most lensboards are simple affairs, a board with a hole in it basically and a rim to help make it light tight. You attach the lens to the board in one or two obvious manners. The speed and aperture are set on the lens shutter, usually.

Lenses in barrel have no shutter.

So all you need to know is if your shutter is small enough to fit in your camera. If you have a 4x5 or smaller camera be careful of old large shutters that say "#5". Everything else will probably work.

Measure your bellows draw, subtract half an inch for safety, and that is likely to be your maximum lens focal length.

That's all there is to it. One thing about LF is you have a dizzying availability of lenses.

Trevor Crone
18-Oct-2000, 15:09
Padraig, If your serious about LF work then get yourself just two books, 1) The Camera by Ansel Adams, 2) Using The View Camera by Steve Simmons. Also treat you rself to the occassional copy of View Camera mag.

Brian C. Miller
18-Oct-2000, 15:26
I learned just about everything I know about LF from reading Adam's "The Camera." This is a great book, and you won't go wrong with it. Buy the rest of the books in the series, too: "The Negative" (it's about exposure and processing) and "The Print".

What camera do you have? It sounds like you have just aquired a camera with no lens.

The lenses are set like any other -- shutter speed and apeture. Only antique lenses will come without a shutter.

One thing you can do is drop by a camera store specializing in used cameras, and look over their inventory and ask for help. They'll be happy help you and sell you what you'll need.

Padraig O'Blivion
18-Oct-2000, 15:41
thanks for the tips on the books.

I just bought the rudiments of a sinar f; rail, front and back F standards, glass, bellows, Lensboard (copal 1), no lens. 400 bucks. One more stupid question; the pictures I have seen of sinar f backs seem to have another piece over them that has two levers on one side , and one above and one below. (see: http://cgi.ebay.com/aw-cgi/eBayISAPI.dll?ViewItem&item=469663515 ) Mine doesn't have this on the back, am I missing a piece?

William Leviit
18-Oct-2000, 17:07
Those 2 levers are used to aid in the insertion of the film holder. Some backs have them, some do not. They are not essential.

Padraig O'Blivion
18-Oct-2000, 17:23
ok, thanks for that. should the film holder be inserted on the side of the gg holder with the hinge? I know the gg holder can be rotated. The hinge is on top now. that would seem to be the most logical place to insert the film holder, not from the bottom, even though it looks like it might go in that way. turning it once to the left would allow me to slide it in from the right side, but then the shutter cable hookup would be on the right side, not the left??????

Ellis Vener
18-Oct-2000, 17:31
Well if you have read some of the existing threads where I've made comments you'll see I am not in the habit of spewing drivel. And now that you have provided some real information (make of camera etc.) it is easier to give you some real information in return.

It sounds like you have a very old Sinar F (current models are the F1 and F2) and that you have the older style back on the camera that lacks the "bales" -- a lever system that makes it easier to smoothly insert a film holder without putting any lateral stress on the camera. Stress that could move the camera or cause the back to swing around the rear pivot point. As far as the additional frame over the groundglass: that is probably the optional removable fresnel screen and frame which makes it easier to see the entire image and to focus the camera. The Sinar cameras are pretty much completely modular and it is possible to replace the groundglass frame you have with the newer design, which I believe is designated as an"MB back". A trip to Sinar's website will help you a lot to see the range of accessories availible to you. It is a very extensive system. Since your camera is an older one you might want to send it to your local Sinar Bron distributor to get it checked out and brought back to factory specs.

The differences in large format lenses boil down to some basic categories: focal length; angle of coverage of a particular lens and size of image circle at infinity. It is easy to confuse the last two. All lenses when focused at imfinity project an image of a certain diameter and angle of coverage refers to the full angle angle projected at that diameter. Angle of coverage does not refer to angle of view inside a particular format. For example: A 90mm lens with an angle of coverage of 106 degrees and an image circle of 235mm is a very wide angle with a 5"x7" camera, a wide angle (approximately equal to that of a 28mm on a Nikon or Canon or Leica 35mm camera); or a normal lens with a 6x7cm or 6x9cm format. The big three manufacturers of modern lenses for large format photography are Rodenstock, Schneider and Nikon. Fuji also makes very high quality glass for large format cameras but they are not distributed in the United States except through a few dealers who act as direct importers. If you are in the United States or Canada, you should also consider purchasing Caltar II lenses from Calumet (http://www.calumetphoto.com). The current series of Caltar II lenses are made by Rodenstock (to the same specs as lenses imported by Rodenstock's USA distributor) and imported with Calumet's proprietary branding. Virtually every large format lens today comes mounted in a Copal shutter which is calibrated for that lens in terms of f-stop (aperture) and shutterspeed.

Enjoy your new camera! Large format photography is a great way to explore the world and your creative vision.

Trevor Crone
18-Oct-2000, 18:08
Padraig, considering you have a Sinar you may like to read the books in the seri es "Creative Large Format" by Urs Tillmanns these are directed to Sinar uses.

Padraig O'Blivion
18-Oct-2000, 18:19
Thanks all for the book tips. found the Adams books for $6.95, hardcover, Simmons for $12.99 and the Tillmanns book for $10.00!

Is anyone familiar with a book called _Camera Movements_ printed by Verlag Grossbild?

Kevin M Bourque
18-Oct-2000, 23:12
Made up or real, I just love your last name. :-)

William Leviit
19-Oct-2000, 05:03
Film holders should be inserted on the side of the GG without the hinge.