Stacking lenses for macro photographing

[anders_stavland]

<p>I want to use a inversed 50 mm lens stacked in front of a 200 mm lens in front of my camera. I know that I could reach 4x magnification this way. While focusing this 200 mm lens and also put the object a a greater distance could I be able to focus so that the down to about 2x life size on the sensor?<br>

Put another way, would I be able to take photos at magnification from 4x down to about 2x life size with the kind of equipment I have described above.<br>

Thanks for replying.</p>

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[stemked]

<p>Hi Anders.<br>

I used to do it some, but admittedly I haven't done it in many years. You do get incredible magnification (I don't recall what it was tough) and very narrow depth of field. I used to do it with my 80-200 f4.7-5.6 A or 100mm f4 A macro with my 50mm f1.4 A (or Takumar) reversed, all with a 49mm filter thread. I bought the reverser at B&H. The biggest problem with film was vignetting (especially the zoom) and the fact that you have to get very close to your subject. The only way to really focus was with a focus rail (I have a Pentax macro slider III). Moving back and forth to get in in focus would otherwise drive you crazy. For that reason and others I simply stopped doing the practice. 1:1 is generally sufficient for my needs anyway.<br>

<em>While focusing this 200 mm lens and also put the object a a greater distance could I be able to focus so that the down to about 2x life size on the sensor?</em><br>

I can't say for sure, but I don't think so. Again I recall having to get very close to my subject. For what you are talking about I think you want a teleconvertor.<em><br /></em></p>

[dave_s]

<p>I did some technical photography using this kind of setup, about 25 years ago. I used a 50 stacked on a 135, with good results.</p>

<p>With a 200 prime and a 50 as the accessory lens, you will get no less than 4x magnification. You can go higher, by extending the focusing helix or putting the setup on tubes. But I believe you won't be able to get down to 2x with this combination.</p>

<p>If you want 2x, a good cheap solution would be to locate a lens reversing ring. Simply mounting a retrofocus lens backwards will give you considerable magnification. I would guess it would be around 1x, but it will depend on the lens and I haven't done this for a long time so my estimate may be out a bit. You can increase the magnification by putting that reversed lens on tubes or a bellows. </p>

[joseph_wisniewski]

<p>Dave is correct. The magnification range for a 50mm coupled to a Nikon 200mm f4, for example, is 4x with the 200mm focused to infinity, 6.6x with the 200mm focused to 1:1. The image quality at that 6.6x setting is pretty horrid, you're asking the 50mm to focus to 280mm, and most 50s suffer heavy aberrations and reduced resolution when focused that close.</p>

[roy_nash]

<p>I used to do this years ago before the days of digital. I hope I can remember something useful. <br /> 1. 50mm lens designs differ considerably. Some will give a much better effect. I was a member of a camera club and as members we experimented with all kinds. I believe that the faster lenses are better (f1.7 for example). This is partly because the image is brighter when viewing but also because they tended to be better made lenses. Pentax M series and similar Cosina lenses were the ones I used.<br /> 2. The reversed 50/200mm is about the best combination. I've tried other coupled lens combinations. The technique was quite common at one time. You should be able to get information by looking in old 35mm photography books. "Reverse coupling" is a more correct term for this type of photography and not "stacking". I believe "stacking" is the term used when more than one close-up supplementary lens is combined to increase the close up effect. It is also a multiple exposure technique used for macro photography to gain maximum depth of field. <br /> 3. I agree with others who have said that beyond 1:1 you will have the problem of a very restricted depth of field which will make focusing without a focusing rail extremely difficult. <br /> 4. If your subject is very flat and reasonably transparent (eg. an insect wing or a petal ) and can be mounted in a slide, you can get great pictures above x 4 magnification using an optical slide-copier or digital scanner.</p>

[profhlynnjones]

<p>Hi Anders,</p>

<p>I think you are doing it the hard way, the stack only shortens the focal length so that the lens to film distance is a greater percentage of the focal length. Furthermore the liklihood is that the stacked lens will have a narrower aperture causing some exposure problems. The best thing to do is to buy a set of Plus Diopters (imprperly called close up filters) which will cost you from 40 to 60 bucks and you will have no difficulty in exposure because while the diameter of the lens is the same, due to the shortening of the focal length, the f stop is greater. In macro I also like to use tele extenders. Since the distance is only a few inches away from the subject the is no optical loss provided that you don't open the aperture, simply increase the exposure with light.</p>

<p>Lynn </p>

[paul_de_ley]

<blockquote>

<p>While focusing this 200 mm lens and also put the object a a greater distance could I be able to focus so that the down to about 2x life size on the sensor?</p>

</blockquote>

<p>No, AFAIK (which is admittedly not very far) working with reversed lenses means your working distance from object to rear element -which is now in front- always equals the register distance that lens was designed for = the distance from lens mount to film/sensor plane. That's true (I think) regardless of whether the lens is reversed directly on the camera, or on another lens. Hence the formerly fairly common use of reversed enlarger lenses or movie film lenses, which are usually designed for longer register distances so don't require you to get as close as the one to two inches that most reversed SLR lenses would constrain you to. Am looking through Lester Lefkowitz' classic "Manual of Close-Up Photography" right now but can't find the section where he talks about focusing lens stacks & their working distances.</p>

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