Close up lenses (diopter lenses)

[alanrockwood]

I have been looking for some good test information on simple diopter lenses. I often see statements like "image quality suffers", but I have found it almost impossible to find actual test results, especially results under relevant conditions, e.g. with the main lens stopped down to to get good depth of field. One of the few examples I have found is on p. 46 of The Manual of Close-Up Photography by Lester of Lefkowitz. He showed several comparison images, and the image with a +6 supplementary lens on an f/1.4 main lens stopped down to f/11 was actually pretty good, not quite a good as a true macro lens at the same magnification and stopped down to the same f-number, but not all that far behind.

I wonder how a lower power supplementary lens would fare under lower magnification, like using a +2 diopter or even a +4 diopter. My guess is that it would probably be quite good when stopped down to ~f/11.

Also, I wonder how the supplementary lens would work on the macro lens. In other words, suppose one were to shoot an object at f/11 at the same magnification with the same main lens, a macro lens. This would take one variable out of the system compared to the test done by Lefkowitz, i.e. by using the same main lens. Alternatively, one could compare an f/1.4 lens (stopped down to f/11) under two conditions giving the same magnification, one using extension tubes and one using a supplementary. This would help isolate the effect of the supplementary lens from other system variables.

Are any of you aware of "good" tests of simple supplementary lenses, i.e with the main lens stopped down?

By the way, let us just stipulate up front that achromatic doublet diopter supplementary lenses will probably give better results than simple supplementary lenses, but it would be interesting to know just how much better.

 

[Dan Fromm]

Alan, this is an old question. From the late '60s through the late '70s, Modern Photography Magazine ran educational articles on a two year cycle. Every two years up popped "Diopter or extension tube? Which is better?"

They tested mainly with 50 mm lenses for 35 mm SLRs. Their best advice what that which is better depends on the lens. Some of the lenses did better on an extension tube than behind a diopter (tests at the same magnification, of course), others did better behind a diopter than on a tube. MP's advice was to try both.

If you want to play with a supplementary lens as a taking lens, by all means do. But remember that the supplementary's focal length = 1000/its power in diopters. A low power diopter will need a lot of extension to get much magnification.

 

[wiltw]

Also, an additional factor about the quality of close-up lens shots is whether the close-up 'filter' is a single element or a dual element optic. Units from Nikon and Canon are dual element, whereas the ones offered by most filter manufacturers are single element (Schneider has been reported to have a duel element offering). Unfortunately, it has been reported that Canon discontinued theirs, but it might be possible to find one on eBay.

 

[alanrockwood]

Also, an additional factor about the quality of close-up lens shots is whether the close-up 'filter' is a single element or a dual element optic. Units from Nikon and Canon are dual element, whereas the ones offered by most filter manufacturers are single element (Schneider has been reported to have a duel element offering). Unfortunately, it has been reported that Canon discontinued theirs, but it might be possible to find one on eBay.

The doublets appear fairly frequently on ebay. That's where I bought a 250D and a 500T.

 

[thuggins]

Years ago, before getting any macro lenses, I used a cheap set of Tiffen close-up lenses as well as a set of extention tubes. The results with the close up lenses were pretty good and there was never an obvious difference between them and the extension tubes. Given that the lenses are easier to use and carry they became the preferred solution.

 

[chip j]

But a mess of Chinese close-up lenses for pennies!

 

[ciniframe]

Don't forget that with close up lenses to get higher reproduction ratios use longer lenses. Can't get a small enough field with a 50mm lens? Switch to a 135mm lens. You will gain working distance between the lens and subject (often useful for small critters) and you can often use a lower power diopter and still get a high enough reproduction ratio. The lower power diopter will present fewer problems with degraded image quality.
Example;
A 50mm lens focused at infinity using a +4 close up lens will have a field size of about 120mm X 180mm at 10 inches from the front of the lens.
A 135mm lens focused at infinity using a +2 close up lens will have a field size of about 95mm X 142mm at 20 inches from the front of the lens.
So think of more than the standard 50mm lens when using close up lens sets. This is also why, if possibile, it's nice to have the same filter size on the lens set for your SLR, at least within the range of wide angle to short tele.

 

[Sepia Hawk]

And how does one use a close up lens on a rangefinder?

 

[Dan Fromm]

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.

N-12A (Close-up Photography) describes how to make and use a focusing frame, shows pictures of RF and simple fixed-focus cameras with focusing frames.

Get an SLR, use a proper macro lens.

I haven't looked at Gibson for a while, don't recall whether he discusses mirror boxes for interchangeable lens RF cameras. That's what some people did before the Exakta arrived.

Get an SLR, use a proper macro lens.

 

[AgX]

And how does one use a close up lens on a rangefinder?

The most simple way would be to use a wire frame of appropriate aspect-ratio and size mounted at the appropriate distance from the camera and put that around the subject.

 

[dourbalistar]

And how does one use a close up lens on a rangefinder?

A Japanese company called Pleasant made a series of close-up lenses called Auto-Up Super Nooky for different (screwmount) rangefinder cameras and lenses. Most of them were clamp on diopter lenses with an attachment to compensate/correct the magnification and parallax for the rangefinder windows. APUG member Lamar has a (there was a url link here which no longer exists).

Leica made an accessory called the ADVOO, but the camera/lens compatibility list looks short. Leica also made some close focus attachments like the NOOKY, but as I understand it, those are more like short macro extension tubes with correction for the RF windows than lens diopters (with an optical element).

 

[mdarnton]

The answer to the question depends on what you are doing and what you expect. If you are copying flat documents, CU lenses will not satisfy you. If you are shooting flower photos, they might. The first thing that's going to go is the quality as you move for the center, and for a lot of closeup work this won't matter at all. A full set is about $12 on ebay, so you should just get a set and answer for yourself what will happen.

 

[Dan Fromm]

Michael, won't framing and focusing be a problem?

 

[mdarnton]

Did I miss something? The OP isn't talking about RF cameras, I don't think. Your're right---with a RF it would be a nightmare!

 

[darkroommike]

And how does one use a close up lens on a rangefinder?

It's not that hard, a wire frame is useful but not absolutely needed. Focus the prime lens on the camera to infinity. A +1 diopter has a 1 meter focal length so that's the distance to your subject. A +2 is 0.5 meter so about 19.5 inches. A +3 is 0.33 meter or about 13 inches. In each case the focal length is the reciprocal of the diopter times 1 meter.

 

[wiltw]

It's not that hard, a wire frame is useful but not absolutely needed. Focus the prime lens on the camera to infinity. A +1 diopter has a 1 meter focal length so that's the distance to your subject. A +2 is 0.5 meter so about 19.5 inches. A +3 is 0.33 meter or about 13 inches. In each case the focal length is the reciprocal of the diopter times 1 meter.

Distance is not the issue, it is the issue of parallax in any rangefinder, which is offset from the lens axis...the wire frame defines the area captured by the sensor/film, which is shifted from the area identified by the rangefinder window at macro distances. Even rangefinder windows with automatic parallax correction cease to provide additional correction at closer-than-usual-minimum distances

 

[John Koehrer]

It's not that hard, for distance; a twine with knots at the measured distances. darkroom mike
has some in #5 that, and the aforementioned frame and Bob's your uncle.

 

[RalphLambrecht]

It's not that hard, a wire frame is useful but not absolutely needed. Focus the prime lens on the camera to infinity. A +1 diopter has a 1 meter focal length so that's the distance to your subject. A +2 is 0.5 meter so about 19.5 inches. A +3 is 0.33 meter or about 13 inches. In each case the focal length is the reciprocal of the diopter times 1 meter.

You are sayingf=1m*1/d. This is hard to understand for me. Is this independent of the focal length of the lens?How does a +1diopter affect a 50mm lens for example?

 

[dourbalistar]

Did I miss something? The OP isn't talking about RF cameras, I don't think. Your're right---with a RF it would be a nightmare!

And how does one use a close up lens on a rangefinder?

The OP wasn't talking about RF cameras, but Sepia Hawk revived the 2016 thread today with a question about RF.

 

[darkroommike]

You are sayingf=1m*1/d. This is hard to understand for me. Is this independent of the focal length of the lens?How does a +1diopter affect a 50mm lens for example?

Works just like reading glasses, Ralph. If the lens (any focal length!) is focused to infinity then the lens with a +1 diopter added focuses to 1 meter, with a +2 it focuses to 1/2 meter, with a +3 it focuses to 1/3 meter, etc. The math gets much more complicated if you focus the camera's lens to anything but infinity but in general, and using your example of a 50mm lens: a 50mm lens has a diopter of +20 so using it with a +1 closeup lens yields a new focal length of +20 + +1 or +21 1000mm/21 gives a new focal length for the combination of 47.62mm, now for any given lens extension you are getting slightly more magnification, a 50mm lens with a +20 diopter yields 1000mm/40 or about 25mm for effective focal length. Those with a background in physics or optics will dispute the exact math but this is fieldwork rough approximations not exactitude. The easiest way to get that +20 is to reverse mount another 50mm SLR lens onto the front of the lens mounted on your camera! Use the front lens wide open and only employ the aperture on the lens mounted directly onto your camera.

Positive diopters shorten the effective focal length of the "primary" lens.

Negative diopters increase the effective focal length of the "primary" lens. e.g. the old Kodak Portra adapters.

 

[darkroommike]

Distance is not the issue, it is the issue of parallax in any rangefinder, which is offset from the lens axis...the wire frame defines the area captured by the sensor/film, which is shifted from the area identified by the rangefinder window at macro distances. Even rangefinder windows with automatic parallax correction cease to provide additional correction at closer-than-usual-minimum distances

I only do this for still life and in the past have used a yardstick to measure subject to camera distance and also used it to figure where the optical center of my subject is and place it along the camera lens axis.

 

[Sepia Hawk]

Yeah, sorry for reviving the thread, but I didn't want to start a similar one. Thank you all for your comments. I asked, because there are Kodak close up lenses available for my new-to-me Medalist. Since it is normally impossible to focus it on anything closer than 3 feet or so (I don't remember at the moment) I was wondering how they were used and why. In 35mm I would definitely prefer a macro lens.

 

[Dan Fromm]

Hmm. For closeup work you want a camera that allows focusing through the lens. With 2x3 that means a press, technical or view camera on a tripod. I've shot flowers at magnifications up to somewhat above 1:1 with 2x3 Graphics and a variety of lenses including a really good Reichert macro lens. Too few of my shots came out as hoped. Between the time I've focused and composed and the time I take the shot -- time spent closing lens, cocking shutter, attaching roll holder, pulling the dark slide and, finally, grabbing and pressing the cable release -- the wind will usually have moved the flower, losing focus. Oh, yeah, I shoot flowers with flash. Motion blur isn't a problem, subject movement is.

For closeup work with smaller roll film formats you want an SLR with a macro lens that has an automatic diaphragm. There are many in 6x6 and 6x7, one in 6x8. I'm well aware of 6x9 Arca-Swiss Reflex, Musashino Optika and Plaubel Maki- and Pecoflex. Rare, rare and rare. Fragile, fragile and perhaps robust.

You did nothing wrong by reviving the thread. You're not responsible for well-intentioned posters who want to be helpful but haven't read recent posts and assume that the thread hasn't drifted.

 

[darkroommike]

Hmm. For closeup work you want a camera that allows focusing through the lens. With 2x3 that means a press, technical or view camera on a tripod. I've shot flowers at magnifications up to somewhat above 1:1 with 2x3 Graphics and a variety of lenses including a really good Reichert macro lens. Too few of my shots came out as hoped. Between the time I've focused and composed and the time I take the shot -- time spent closing lens, cocking shutter, attaching roll holder, pulling the dark slide and, finally, grabbing and pressing the cable release -- the wind will usually have moved the flower, losing focus. Oh, yeah, I shoot flowers with flash. Motion blur isn't a problem, subject movement is.

For closeup work with smaller roll film formats you want an SLR with a macro lens that has an automatic diaphragm. There are many in 6x6 and 6x7, one in 6x8. I'm well aware of 6x9 Arca-Swiss Reflex, Musashino Optika and Plaubel Maki- and Pecoflex. Rare, rare and rare. Fragile, fragile and perhaps robust.

You did nothing wrong by reviving the thread. You're not responsible for well-intentioned posters who want to be helpful but haven't read recent posts and assume that the thread hasn't drifted.

I recall a ground glass accessory back for the Medalist?

 

[Dan Fromm]

I recall a ground glass accessory back for the Medalist?

Correct, but it could be swapped with a sheet film holder, not with a roll film holder.