alanrockwood
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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.
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).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.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.
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?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.
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?
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.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?
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.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 recall a ground glass accessory back for the Medalist?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?
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