Anybody used a macro coupler with the kit lens ?

[sid]

I searched the forum and although I found some great tutorials on using a macro coupler with different lenses, I was unable to find anything pertaining specifically to the 18-55 kit lens. So, here's what I was thinking of doing (and I may be completely wrong here, so please feel free to correct me)
Camera -> kit lens -> coupler -> 50mm f/1.8
Is this possible ? Or would it be better to do this:
Camera -> 50mm f/1.8 -> coupler -> kit lens

Has anyone tried something like this with the kit lens ?

[C.S.I.]

I think the protruding rear element on the EF-S kit would prevent using the coupler.

Also, I think your not supposed to use a wide angle while coupling for a macro effect, due to abbhoration/shadowing.

[jyrgen]

I don't have these particular lenses, but I have coupled a few others. Physically it will work fine both ways (rear element does not play a role because you couple front elements). In terms of actual usability, I believe both ways vignette at most combinations. I guess that Camera -> kit lens at ~50-55 -> coupler -> 50mm f/1.8 would not vignette and give you a usable more-than-1:1 macro.

Generally my (limited) experience shows following:
- The second lens works as a high diopter magnifier lens. In order to have no vignetting, it must have physically large aperture throughout the lens barrel. Which means fast normal primes. I have 50/1.4 and 55/1.2, both work excellent, so I believe 50/1.8 is fine too.
- The first lens should rather be a telephoto one, because in order to not give vignetting, it should "look" only through the center (glass only) part of the second lens, i.e. have a narrow FOV. But too long lenses give too much magnification (see next point), so they maybe not that good. E.g. 85/1.8 coupled with 50/1.4 is excellent.
- Magnification equals focal lenght of the first lens divided by focal lenght of the second lens, that is in film terms maybe, I don't have an opinion whether it should be corrected with crop factor.
- Working distance (I mean distance from lens to subject here) is very very short with any combination. So for practical purposes (esp living subjects) coupled lenses are difficult to use.

[C.S.I.]

I don't have these particular lenses, but I have coupled a few others. Physically it will work fine both ways (rear element does not play a role because you couple front elements).


You are correct.....my bad......statement made pre java :cry:

[sid]

Thanks for the input jyrgen. That explanation helps me understand it much better. :)

[jyrgen]

Let me add few examples from recent experimentation. You can see the vignetting I told about. First, to explain the scale, here is a toy african feline of some kind that I used as a subject, it's head is maybe 2cm long:

http://www.hot.ee/jyrgen/050314_9914.jpg


Now the coupled macros, downsized full frames, identified by first lens/second lens focal length:


50/85:
http://www.hot.ee/jyrgen/050315_9926.jpg


50/55:
http://www.hot.ee/jyrgen/050315_9931.jpg


85/55:
http://www.hot.ee/jyrgen/050315_9937.jpg


100/17(?):
http://www.hot.ee/jyrgen/050315_9943.jpg

I guess it was 100/17, using Canon 100-400/4.5-5.6 and Tokina 17/3.5 (which is too dark and vignettes when first lens is at 100). Unfortunately there is no info on the second lens in EXIF ;)

Another day I used Sigma 24/1.8 on 100-400 and it has aperture wide enough for longer lenses to see thru it without vignetting. Here is one with this combo, my English lacks the word for that subject, but it's a part of an orange that most probably once held the orange onto the orange tree or branch of that but now is the first thing one throws away before peeling the orange:

100/24:
http://www.hot.ee/jyrgen/050319_0204.jpg


Unfortunately I don't have any sturdy tripod, otherwise I'd gladly show you the magnification of 400/17 lens combo, but you'll find a 200/17 if you do a search of my older posts.

[sid]

Thats impressive and educational. I can see exactly what you meant in your earlier post. I cant wait to try it out myself. Thanks for the help with this :)