[cyberjunkie]

Waiting for the Macro-Elmar-R 4/100mm (that will be leitax'ed), I've read some info on the Web about this specific lens.
IIRC Leitz offered three different ways to increase the poor magnification ratio (less than 1:2).
Bellows.
Teleconverter.
Screw-in close-up achromatic (Elpro). If I'm not mistaken a very good three-elements.

It made me think about other 1:2 macro lenses, sold with a separate accessory that brought the ratio to 1:1.
My Tokina made Soligor 2.8/100mm Macro has a simple empty tube.
The Tokina 2.5/90mm was sold with a macro converter (with a rather complex optical layout).
So did the Vivitar version of the Tokina.
To transform a normal 50mm in a macro there were two kind of macro converters, the Kenko and the Panagor/Elicar. The former was a conventional teleconverter on a helicoid, the latter didn't change the extension but the internal position of the internal elements, like an IF objective.

I am very curious about the performance of the two systems (empty extension tubes vs optical devices).
It would be interesting to know if anybody tried to use the Tokina/Vivitar with both the optical macro converter and with extension tubes, and which were the results.
In theory the optical macro converter should give sharper pictures.

cheers

Paolo

[tvdtvdtvd]

I would think the optical system would give you better working distance but perhaps reduced resolution because of the extra glass.
Extension tubes shouldn't alter the light path, so no direct drop in resolution but you will have a bit of light drop-off, (reduction in speed).

Most of my experience is simply using extensions tubes. I do have the Vivitar 90/2.5, but not its 1:1 adapter.

[pres589]

Tubes are better, macro filters are cheaper. And the k-mount ecosystem isn't great about tubes but with a lens that's been Leitax'd you can use just about any cheap simple tube you can find.

[Wasp]

A bellows on a tripod gives you a lot more control in terms of exposure, magnification and working distance than tubes or screw in lenses. The extra extension also gives more magnification, with accompanying loss of light. Which means you need the adjustability even more.

The downside is that hand-holding a bellows is not really an option. It takes up more room in the bag. And it is just a bit fragile. In comparison a set of extension tubes is just about indestructible.

[kypfer]

The advantage of using a good quality tele-converter rather than tube(s), as per Tamron's alternative solutions for their succeeding generations of Adaptall 90mm macro, is that the converter gives a better (further) working distance for a similar degree of magnification, less likely to spook butterflies etc. and can help keeping troublesome shadows out of shot. You also retain longer-distance focus, out to infinity if necessary, with the tele-converter

[cyberjunkie]

Of course I am aware of the difference in terms of distance from the subject, keeping the same magnification ratio.
I asked about something different.
I want to know if anybody has ever tried to do a first hand test/comparative because between a lens with the dedicated 1:1 optical extender, and the same lens used with bellows/tubes.
The answer is not to be taken for granted. It's not that simple.
Depending on the typology (optical design) the performance can be completely different... and of the three options, the close-up dioptric lens is not always the worst.
Check the link that follows.
There is comparative test, done by Marco Cavina, using two vintage Leitz macro lenses (60mm and 100mm).
One does better with the tubes, the other with the extender. Both do even better using the Elpro diopter (achromatic triplet, if I remember correctly).

Leitz_macro-adapter-r_vs_extender-r

Reading that article I thought that it would be interesting to try the Tokina/Vivitar 2.5/90mm at 1:1 magnification ratio, with both dedicated extender and extension tubes.

[kernos]

First find a bokina dedicated extender and no the Tokina and Vivitar versions are incompatible.

[cyberjunkie]

First find a bokina dedicated extender and no the Tokina and Vivitar versions are incompatible.

Do you mean that the Tokina macro extender is not compatible with the Vivitar, and vice versa?
I thought tthe difference between the two lenses was just cosmetic