Thanks for that reply - nicely put - and SUPER helpful. I can see where if I had trouble with the MP-E that I will have trouble with Bellows. I just purchased some Kenko Extension tubes and a new 50mm f2.5 macro - although I didn't really need the lens, it will be a nice addition to my stuff, and I think give me an easier lens to work with.
I think I will start here with macro - using the tubes on a variety of lenses. I do have 70-200 f2.8 with a 1.4 extender, but that lens is not macro and it is my only lens that works with that particular extender - so I am not sure how well it would work with the tubes?
Normally extenders (teleconverters) are optimized for use with a particular kind of lens but also will work with others although the image quality may suffer. Try it and see. If you add tubes to the affair, they go between the teleconverter and the lens. The teleconverter is designed to be mounted on the camera and must stay there for best quality.
I am thinking about the bellows and rails still - I think I may get them so that if I am having success with tubes and want to move on I can. Its the much cheaper way I think for me to get further in. The bellows/rails I am thinking of cost only $100 after shipping, and so understanding I get what I pay for, I wont be dissappointed if I find in the future I want the MP-E. GREAT advice on the live subjects, I understand how the MP would work there. How difficult is it to adjust bellows to correct focus?
I'm a great fan of bellows for studio work. I think you'll be pleased with what you can do, but it is important to keep the limitations in mind. There are several ways that a bellows can be focused. Most people set the bellows length to establish magnification, lock the front and rear mounts, then use a focus slide to move the camera and lens as a unit. In this case what matters is DOF versus how smoothly you can move the focus rail. At high magnification, DOF gets quite thin. For example at 3X and f/8 set on the lens, you will be running at an effective f/32 but even so your DOF will be only about 1/5 mm using the standard criterion for "sharp".
What can you tell me about reversing rings? I understand how they work and the concept, what I don't understand is the set up. I need a reversing ring - does that mount to camera, extension tube, bellows, other lens? Do I need to mount another lens on the back side of that?
Reversing rings can be used in any of the ways that you mention.
To quickly review, the main purpose of reversing a lens is to reduce aberrations by putting the short focus distance on the mount side of the lens where the lens designer intended it to be.
A typical reversing ring has a male filter thread on one side and a bayonet mount to fit your camera body on the other side. That same mount fits extension tubes or bellows, of course. You get minimal extension by reversing the lens directly onto the body, more by adding some tubes, and more yet by adding a bellows. There is no other lens in this case -- just the one lens, reversed, on more or less extension to get whatever magnification you need. You can get a large range of magnification by using different extensions
Reversing rings are also made that have male filter threads on both sides. These rings are used to make "lens combos" or "stacked lenses" (distinct from focus stacking), by reversing a short lens in front of a long lens. In that case, the overall magnification is simply the ratio of focal lengths, rear/front, so for example reversing a 50 in front of a 200 will give you 4X magnification. Stacked lenses are commonly used with compact cameras that do not have interchangeable lenses. They are also used sometimes on DSLR's, particularly to get high magnification in the field. In my experience, most lens combos don't actually give very good images, due to aberrations that appear because the lenses were designed to be used separately, not together. Once in a while the results are excellent. Of course those are the ones that people publish so they are the ones you hear about. Most of the combos that I've tried do not make images that make me happy, and some of the ones that will make good images have to be used in awkward manners, like manually stopping down the front lens instead of automatically stopping down the rear lens. See
Stopping down a lens combo for some discussion/illustration of that.
One earlier reply mentioned reversing an enlarging lens. This is an inexpensive and very effective method of getting good results in the 2X-5X range where other methods tend to fall down because the lenses aren't designed to work there. But of course enlarging lenses have manual diaphragms, so they're not ideal for working with live subjects.
Stacking - I have not researched on this forum yet, so its probably here somewhere. What software is used? I have photoshop CS4 and am a fairly advanced user. It has HDR options, is their a similar function for Stacking, or do you use specialty software?
Photoshop CS4 does have focus stacking, but most reviews say that it's not as good as the specialty packages. See
HERE for some links about that. The most commonly used specialty packages are CombineZP, Helicon Focus, and Zerene Stacker. CombineZP is free and can be talked into giving very good results, but the user interface is a bit clunky and it's Windows only (or Mac with Windows emulation). Helicon Focus is a commercial product that's been around for years. It's a very solid piece of work, but it hasn't kept up with state of the art in stacking algorithms and it has trouble with deep stacks with certain kinds of subjects. Zerene Stacker is a new product that was in public beta from April through September, but now has switched over to the usual purchased license after 30-day free trial. There is a comparison of Helicon and Zerene
HERE.
You are an awesome help!
Thanks. I learn a lot by answering questions.
--Rik
