[Just1MoreDave]

I don't think anyone makes tubes with a K-mount and aperture levers any more; used is the only way. The good news is, they are unlikely to be worn out or broken. They are just tough to find. I got a set when I was looking at every possible thing for sale on eBay. A guy in Canada was selling a worthless zoom with a set of tubes attached and not mentioned in the listings. I was the only bidder. I asked him to keep the worthless zoom and just send me the tubes. I had to sand away part of the black anodized mount to trick the camera into seeing them as a lens:



I also got a worthless Sears 3X teleconverter and a couple of 2X teleconverters with contacts. I removed the glass to use them as tubes. These are easier to find for sale, or included as extras in a set of other stuff. The 2X teleconverters all seem to be 25mm long. My 3X tube is about 50mm. The teleconverters have aperture levers so with no glass they are exactly like tubes.

If you are shopping, look for a Vivitar Macro Focusing 2X Teleconverter. In your case, save some money and get the version without contacts. It is a variable length extension tube with some optical elements. The optics are pretty good, so worth keeping. It was designed to use with a 50mm prime lens.

My reversing ring was also part of a lot of camera gear. It's an old Kiron Reverse-Mate. All the old stuff is hard to find, but really built well, so it's worth the hunt.

Edit: it's a Black-eyed Susan.

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Last edited by Just1MoreDave; 08-01-2014 at 10:32 AM.

[Mistlefoot]

4 - What's the difference between using a teleconverter without glass and using an extension tube?

I can mostly answer this one.

A teleconverter uses glass and basically multiplies the lens (1.4x, 1.7x or 2.0x are the most common). Ultimately, my 90mm 2.8 would be 180mm 5.6 with the only change being the addition of the converter. As you introduce glass and halve the light you are often more challenged at not introducing any flaws that glass introduce. You can use a teleconverter with a long lens as well so they offer the advantage of "zooming" any focal length.

An extension tube offers no glass and simply allows you to focus closer to your subject. So my 90mm 2.8 with 1:1 at 30cm minimum focus would give me something like 2:1 at 15cm minimum focus. No glass to alter the picture and your F-stop remains the same. You probably won't be able to focus at anything at a distance though. While they allow you to focus closer they will no longer focus at infinity.

In the 2 situations above, with the same lens, I'd have the camera 30cm's away from my target for 1:1 with the teleconverter and 15cm's away from my target with the extension tube to get the same shot.

To be clear, I'd have to do the math as I have a few tubes (and they are stackable) but this shows the basic main differences as I see them.

[baro-nite]

I'm very interested in the reverse stacking of lenses (the back element will be protected by the second lens, correct?)

Nope, when stacking lenses you have one lens (the "primary" mounted to the camera as usual. The other lens (the "secondary") is attached with a macro coupling ring (i.e., an adapter with male filter threads on both sides) and has the rear element exposed. You do need to be careful using lenses this way, but plenty of us do this, even out in the field. If you have a spare rear lens cap you can make a sort of hood by drilling a hole in it, to provide some protection.

1 - what reversal rings do you reccomend for reverse stacking of lenses? All the ones I find have very bad reviews that worry me about losing my lenses (or getting the ring stuck to it or the camera).

I have various brands, including at least one no-name. The well-known brands such as B+W feel more solid, but I've never had a problem with any of them.

3 - If I have a fully manual lens, like the K and M series, do I need to worry about an extension tube with an aperature lever? Whenever people talk about auto or aperature controlled extension tubes and teleconverters I never understand what kind of lens they expect us to use with it.

With manual tubes (no diaphragm actuator), when you stop down the lens the image in the viewfinder becomes darker. If you stop down by more than a few stops, it can become almost impossible to see. This can make handheld shooting very difficult. "Auto" tubes keep the diaphragm fully open until you press the shutter release (just like using the lens without tubes).

4 - What's the difference between using a teleconverter without glass and using an extension tube?

Maybe no difference, although de-glassed teleconverters might have more internal reflections than purpose-designed extension tubes. I've seen this with one of my lenses.

5 - Can I stack teleconverters and extention tubes indefinately, limited only by ability to focus and lighting?

More or less, although this can put a lot of force on the camera's lens mount. If you want long extension a bellows is best.

6 - Is there a chance that reverse stacking lenses can damage them, assuming it's not due to bad reversal rings?

I wouldn't use a large or heavy lens as the secondary -- that's a lot of weight to hang off the filter threads of the primary lens.

7 - If I were to use a macro lens with the reverse stacking lens technique would it ruin the flatfield sharpness?

Probably depends on the particular lens combination, but unless you are photographing flat objects (and you've said you're mainly interested in botanical subjects), this won't be a problem.

I almost forgot to ask: with reversal stacking, can I attach a K lens to an M lens, or is the different filter size an issue?

Macro couplers come in various combinations of filter thread sizes.

[Doundounba]

1 - what reversal rings do you reccomend for reverse stacking of lenses? All the ones I find have very bad reviews that worry me about losing my lenses (or getting the ring stuck to it or the camera).

As someone else mentioned, with stacked reversed lenses, the first lens (closest to the camera) is installed normally. So the adapter is a male-to-male threaded adapter. Size depends on the lenses you're trying to couple, and ideally I think you want to use as few step-up or step-down rings as possible. I have a 49mm to 49mm and a 49mm to 55mm and those two work well for me, though one has now gotten stuck on the (inexpensive) zoom I most often use as my reversed lens.

2 - I've heard both good and bad reviews on the cheap ebay extention tubes and I'm very confused about it. I really don't want to lose a lens from a bad tube (I'd rather spend the $65 and save a $100 lens). Should I bite the bullet and buy the $65 tubes or is there a cheaper one that's also good?

Again, as others have mentioned, you really want tubes with aperture coupling so you can focus wide open. These should run you around $50.

3 - If I have a fully manual lens, like the K and M series, do I need to worry about an extension tube with an aperature lever? Whenever people talk about auto or aperature controlled extension tubes and teleconverters I never understand what kind of lens they expect us to use with it.

K and M lenses all have aperture levers and only close down when the shutter fires. Only adapted lenses (like m42) are exceptions to this rule.

5 - Can I stack teleconverters and extention tubes indefinately, limited only by ability to focus and lighting?

I believe at some point the minimum focus point will move into the lens. Also in practice, I find that after ~70mm of extension, the camera just becomes awkward to handle, but YMMV.

6 - Is there a chance that reverse stacking lenses can damage them, assuming it's not due to bad reversal rings?

Sure, the back element is exposed on the reversed lens, as is the aperture lever. You could damage your lens mount or optics by banging the lens on a solid object.

One more thing: don't go for broke at first, magnification-wise. Shooting macro is a set of skills, and it's good to build experience progressively. Start around 1:1 (lifesize). Make yourself a homemade Pringles-can flash diffuser. Experiment, and above all, make sure you're having fun! The risk if you go for high-magnification right away is that you might burn yourself by trying something very difficult too quickly, and then proceed to decide macro's not for you. But take it one step at a time, and eventually you might wind up shooting 6:1 jumping spider macros.

[Paleo Pete]

1. No idea, someone else may chime in though, I've never used one. When I tried it I just used a bit of duct tape.

2. My set works fine but no aperture lever so I have the same problem as your cardboard tube experiment. View is too dark to use, same as with my M42 tubes. Otherwise I Had no problems with them.

3. I would give it consideration, same as above. The aperture lever holds the aperture wide open so you can see to focus, then stops down briefly to take a picture same as just a lens with no extension tube or teleconverter. It makes a huge difference. Without the lever, you have to open the aperture ring to at least f8 or wider to see, focus, then set the aperture ring to the f stop you want to use, and unless you're using a tripod, you just lost your focus if you're not rock steady. That's where my M42 rig has an advantage, it has 2 aperture rings. One is a stop with detents, to set it where I want it to be, the other actually changes the aperture and I can just use my pinkie to turn it after focusing. The stop lets me know when I reach the aperture I want. I would hold out for something with an aperture lever, especially just starting out with macro.

4. None whatsoever. Remove the glass, the teleconverter is exactly the same as an extension tube.

5. Yep. I have 2 K mount teleconverters with glass removed and one K mount extension tube. 20mm, 25mm and 30mm. Mix and match as needed, use one or all, and if you have a dozen your only limitations are the ability to focus and the ability to hold it still enough to stop motion blur.

6. Probably not but I've never used one so I'm not positive. I'm pretty sure it won't damage any glass though, just stacking two with duct tape the filter ring holds them apart and prevents glass damage.

7. Again I don't know, someone else who's tried it will have to answer that one.

With a reversing ring, as far as I know you can use any K, M or A series lens, they just have to have th3 same filter ring thread size. You may also be able to find them to fit different sizes, I don't really know. A far as I know, 2 requirements. The one on the camera has to be a K mount, filter ring threads have to match. (unless you can find one that adapts to different diameters and threads.)

---------- Post added 08-01-2014 at 06:49 PM ----------

Oops, I seem to have missed several replies prior to mine...

[Lovephotography]

Awesome! Thank you everyone for responding! I will take your advice and try to start small and work my way up (though I have found two lenses I'd like to try for reverse stacking, I won't let myself get frustrated and these are lenses I want anyway). Paleo no worries, I always appreciate receiving more than one answer, even if it's the same answer. Every answer gives a tidbit of new information, and all information is valueable ^_^ .

I'm looking forward to my next photography adventure, thanks again everyone!

[WPRESTO]

My $0.02.

For lens-lens mounts, try www/AdapterRings.com.
When doing macro with two lenses stacked, the guidelines are:
1) EXPERIMENT WITH WHAT YOU HAVE. Don't avoid a two lens combination because someone says it will not work. Excellent results may be possible with unexpected combinations of lenses.
THAT SAID
2) generally it's better to have the longer focal length lens mounted directly to the camera.
3) as with normal photography, on the average, SFL lenses give better results than zooms, BUT EXPERIMENT WITH WHAT YOU HAVE.
4) devoted macro lenses don't seem to work as well as non-macros in stacked lens systems
5) short mount, 100mm bellows lenses have a good reputation for use as the second lens (the one reversed).
6) there is debate on which lens to stop down at the moment of exposure. Personally, I always go with the auto-diaphragm of the lens directly attached to the camera, but some expert macro photographers insist that stopping down the reversed lens gives sharper results.
7) 90% or more of my macros taken with flash are sharper and more satisfactory than those taken with ambient light only, even with the camera on a relatively massive tripod.

Another suggestion for low magnification macros (less than 1:1). Canon still makes two element, achromatic close-up lenses in a range of filter sizes and two different strength (lower magnification designated "500," higher designated "250"). These, like the Raynox, can give very good results and are very convenient for travel. I got some good close-ups with a Canon 250 mounted on a Pentax 55-300. Nikon once made achromatic close up lenses (occasionally available used on EBAY, B&H, KEH) in 52mm (designated 3T and 4T, lower/higher magnification) and 62mm (5T & 6T). I have several of these, and again, they are useful when traveling and can give very good results. These two-element filters work best on moderate telephotos (about 70~200mm), although I carry a big Canon unit to use on my 300 f4, for unapproachable small creatures.

NOTE ADDED: I find two-element close up lenses more satisfactory than extension tube(s) on zoom lenses because once focussed on the subject, the focus is maintained very closely when the lens is zoomed. With an extension tube, once the subject is in focus, if you zoom, the subject will go wildly out of focus. This is because as with a series of SFL lenses, the focal distance with a given extension tube is much shorter with a short focal length lens than with a long lens. So a zoom set at 80mm with extension tube, in focus at 15 inches, zoom to 135mm, now the correct in-focus distance is 24 inches.
A Canon "250" close-up lenses sets the in-focus distance to about 250mm when the lens is set to "infinity" regardless of the focal length of the lens, therefore regardless of the zoom setting of the lens.

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Last edited by WPRESTO; 08-05-2014 at 06:19 AM.

[Lovephotography]

Wow great info! I didn't even think about buying canon and nikon lenses for stacking, what a great idea!