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Jerry Cunningham
27-Feb-2006, 13:55
Sir
I am looking at some "close-up" work from flower size to dime size. I have never done anything like this. As I understand it, an apple that fills a 4x5 glass would be one to one ratio (or close). If I want a dime to fill a 4x5 frame is that 1-20 or 20-1? Sorry for the dumb question but I am in the sticks and have no-where else to turn. I am considering a 300mm APO Ronar f9. Am I way off on this type of lens? Any clarity would be appreciated.
Jerry Cunningham

Henry Ambrose
27-Feb-2006, 14:47
I suspect that someone else will answer this more completely but the 300mm lens will require way too much bellows extension to get past 1:1. It'll take 600mm of bellows to do 1:1 - that's already really long! You'll probably want a shorter lens, maybe even a 90 or something like that. There have been very short focal length lenses made in the past for this very purpose, but that's all I know about them. I suspect that you can do pretty well with the lenses you have now - just try them to see what it looks like on the ground glass. One thing you'll run into is that the camera itself will be in the way of the light falling on your subject. Often smaller cameras can give better close-up results easier than larger ones.

Cesar Barreto
27-Feb-2006, 14:55
Hi, Jerry.

I've been doing some work on the same range (about 6 to 8:1)and I would suggest trying smaller focal lenghts, otherwise you'll get impossible long bellows extension. I've used enlarger lenses, 80 and 105mm, shutter mounted for convenience.
The APO Ronar may be a nice piece of glass, but on this range your bellows would measure some 1,5m or more. Not a real pleasure to work, I think.

Good luck.

Alan Davenport
27-Feb-2006, 14:55
A dime is 0.705 inches in diameter. With an image width of just over 3.75 inches on 4x5 film, your magnification will be around 5X, or 5:1, to fill the frame with a dime.

For that much magnification, you'll need a short focal length lens. A typical field camera with about 300mm of bellows, can reach 5X magnification with a 50mm lens or shorter. To get 5X with a 300mm lens, you'll need 1800mm (almost 6 feet) of bellows.

Polaroid sold a series of macro lenses (Tominon brand) with their closeup cameras. IIRC, they ranged from about 105mm (or a bit more) on the long end, down through 75mm, 50mm, 35mm and 17mm. Those lenses are often seen on ebay, but the shorter focal lengths (which you need) are not seen as often as the longer ones.

Also, as the magnification goes up, the light intensity hitting the film goes down. You'll either be making very long exposures, or using lots of flash at 5X.

And don't even ask about depth of field. For all practical purposes, at that magnification there ain't any depth of field. At 5X and f/22, you will have a bit less than 1/2 inch total DOF.

Alan Davenport
27-Feb-2006, 14:58
OOPS! I shoulds said you'll have less than 1/2 millimeter DOF. My bad........

Dan Fromm
27-Feb-2006, 15:41
Jerry, you asked a short question that demands a long answer. Book-length, in fact, and there are books on the subject. Here are a couple, with my take on them:

Gibson, H. Lou. Close-Up Photography and Photomacrography. 1970. Publication N-16. Eastman Kodak Co. Rochester, NY. 98+95+6 pp. The two sections were published separately as Kodak Publications N-12A and N-12B respectively. Republished in 1977 with changes and without the 6 page analytic supplement, which was published separately as Kodak Publication N-15. 1977 edition is ISBN 0-87985-206-2.

Gibson is very strong on lighting, exposure, and on what can and cannot be accomplished. His books, although relatively weak on getting the magnification with lenses made for modern SLR cameras, provide a very useful foundation for thinking about working at magnifications above 1:10 and especially above 1:1. Extensive bibliography.

Blaker, Alfred A. 1976. Field Photography. W. H. Freeman & Co. San Francisco, CA. 451 pp. ISBN 0-7167-0518-4

A deep discussion of all aspects of photography, with considerable emphasis on close-up. Discusses getting the magnification, lighting, and exposure. Weaker than Lefkowitz on working above 1:1, stronger on lighting, especially flash. Extensive bibliography.

Lefkowitz, Lester. 1979. The Manual of Close-Up Photography. Amphoto. Garden City, NY. 272 pp. ISBN 0-8174-2456-3 (hardbound) and 0-8174-2130-0 (softbound).

A thorough discussion of getting the magnification, lighting, and exposure. Especially good on working above 1:1. Extensive bibliography.

Bracegirdle, Brian. 1995. Scientific PhotoMACROgraphy. Bios Scientific Publishers. Oxford. 105 pp. ISBN 1 872748 49 X

A terse drier updated version of Lefkowitz. Very useful bibliography, unfortunately scattered into small sections after most chapters.

All but Bracegirdle are out of print, can be obtained from on-line booksellers found via, in alphabetical order, www.abebooks.com, www.addall.com, and www.amazon.com.

Jerry Cunningham
27-Feb-2006, 18:14
I think I see the picture. Thank you very much for the information. It is beyond price.
Jerry

Ernest Purdum
27-Feb-2006, 18:17
You can find out the bellows extension needed like this. A same size imge/subject ratio takes two focal lengths extension. Every added focal length adds an even number of magnification. Three focal lengths = 2X. Four focal lengths give 3X and so forth.

Alan Davenport's mention of the Tominon lenses makes a lot of sense. Besides being designed for just this kind of work, they fit right onto the front of shutters that Polaroid sold for use with them and they are at present extremely inexpensive on eBay. This is nice because you can find out just how much you are interested in this sort of work without spending a fortune on little pieces of glass. I'd suggest a 75mm to start with if you have enough bellows for it. The longer lenses are designed for copy rather than macro work and the shorter ones are more difficult to use.

Ralph Barker
27-Feb-2006, 18:30
Jerry, there's also a very helpful article about LF macro on the home page of this site:

http://www.largeformatphotography.info/macro.html

written by none other than Ernest Purdum.

Donald Brewster
27-Feb-2006, 20:44
In addition to the Polaroid Tominon lenses Alan and Mr. Purdum suggest, there is also the range of Zeiss Luminar lenses -- the catch being they are more expensive being Zeiss (they are really good though). For the use you are proposing, the 63mm version is probably about right -- closest variant to what Mr. Purdum is suggesting. There is also some good information on micro-photography in the various early 1960s Linhof large format books, particularly the Industrial Photography book. As Alan notes, lighting and DOF are the biggest challenges once you have the right lens.

Dan Fromm
28-Feb-2006, 05:24
Donald, there's a rather less expensive alternative to the 63 Luminar.

55/2.8 MicroNikkor AI/AIS reversed shot at f/4 or smaller. Much superior to all of the 50 and 75 Tominons I've had, beats the 63 Luminar at magnifications >= 6:1. I've tried one MicroNikkor, two 63 Luminars. I attach the reversed 55/2.8 to a #1 using an SKGrimes adapter, male M52x0.75-t0-male M40x0.75.

Ted Harris
28-Feb-2006, 06:44
The options given so far are all excellent. Depending on the criticallity of your application you may also want to explore the currently available large format macro lenses made for this purpose that are available from Schneider, Rodenstock and Nikon. One more consideration, the type of camera you use. There was mention earlier of a field camera and while it will work to a certain extent it is not ideal for macro work. My normal macro setup is always with my Horseman rail camera. Depending on the extent of the magnification I will work either with the long bellows and the extendable rail or with two bellows, a bellows extension adaptor (third standard in the middle) and the 1000 mm rail. The higher the magnification the more light I use but I seldom do macro work with less than 1000 WS. My most used macro lens is the Schneider 180 macro Symmar. Absolute camera rigidity is also a must and, in addition to the camera stand mount, I will sometimes attach a second rail mount to a heavy duty Tele Studex to use on the front of the rail as well. A few more tips that may be useful ......

Aaron van de Sande
28-Feb-2006, 10:13
a 50mm enlarging lens will work pretty well.

William Mortensen
28-Feb-2006, 16:14
Bear in mind that Edward Weston shot his roughly-life size (or larger) and still-much-admired peppers and shells with inexpensive, uncoated 1930's (or earlier) "normal" lenses. He was not seeking the sort of technical perfection Jerry is, but sometimes I have to remind myself that the lens is not as important as the eye.

EW was lucky to have lived in his day. Today he'd probably be wasting his time on ebay and internet forums instead of making wonderful images. (Oops, that reminds me, gotta check the auction results on a lens... )