Recommendations for a lens to give about 6x on bellows ..

AndrewC · Post by **AndrewC** » Mon Jul 20, 2009 2:47 pm

Anyone care to recommend a lens for roughly 6x mag on a bellows / tube ? I keep wanting something between my El-Nik 50mm and my Nikon 10x objective.

Thanks, Andrew

lauriek · Post by **lauriek** » Mon Jul 20, 2009 4:02 pm

You didn't specify a price range so I'll mention the OM 38/2.8 bellows lens I use for this magnification. Not cheap but does a nice job...

AndrewC · Post by **AndrewC** » Tue Jul 21, 2009 12:33 am

lauriek wrote:You didn't specify a price range so I'll mention the OM 38/2.8 bellows lens I use for this magnification. Not cheap but does a nice job...

Are those the Pen-FT lenses that go for several hundred, gulp

?

Andrew

ChrisR · Post by **ChrisR** » Tue Jul 21, 2009 1:58 am

This one I expect:
http://www.alanwood.net/photography/oly ... 38-28.html

lauriek · Post by **lauriek** » Tue Jul 21, 2009 3:30 am

That's the one Chris.

Yes these days they go for 3-400 pounds usually, sometimes more...

AndrewC · Post by **AndrewC** » Tue Jul 21, 2009 3:56 am

lauriek wrote:That's the one Chris.

Yes these days they go for 3-400 pounds usually, sometimes more...

I'll take the one at £3

Andrew

Harold Gough · Post by **Harold Gough** » Tue Jul 21, 2009 8:29 am

lauriek wrote: Yes these days they go for 3-400 pounds usually, sometimes more...

More like £600. I had mine stolen and had to replace it last year.

With that lens, you will pay a premium for the automatic diaphragm, which you can't use in your set-up. The manual version is more often available and sometimes less than half the price:

http://www.alanwood.net/photography/oly ... 38-35.html

Harold

rjlittlefield · Post by **rjlittlefield** » Tue Jul 21, 2009 8:44 am

Harold, do you have any data on how the two versions of that OM lens compare?

People occasionally ask me, but I only have the f/2.8.

The optical designs are different -- 5 elements versus 6 elements. My f/2.8 performs best wide open, almost as good at f/4, and noticeably softer at f/5.6. I'm a little worried that the f/3.5 will have the same pattern, but starting at its smaller aperture. If that's true, then the f/3.5 would have somewhat lower resolution for stacking applications.

Worries don't mean much, of course, so I'd really appreciate some data if it's available.

--Rik

lauriek · Post by **lauriek** » Tue Jul 21, 2009 10:08 am

If you frequent the 'bay and don't mind waiting a few weeks you ought to be able to get one for < £400 (I think I paid about £350 for mine a few months back), but I concede that's still not particularly cheap.

The auto diaphragm is a nice touch on an OM bellows.

I can't compare directly, but my experience of the older 20mm/3.5 olympus bellows lens (with the RMS mount) wasn't particularly good, the aperture is simply not fast enough for the magnification it achieves on 4/3 (or I would guess APS) sensors. However with the 38mm with less magnification the f3.5 version may be okay, and is certainly cheaper...

I just remembered something, search the forum here for "apo componon" and look at NikonUser's posts about the 40mm.

Charles Krebs · Post by **Charles Krebs** » Tue Jul 21, 2009 10:30 am

Whatever you consider, f4 (marked) would be about the smallest aperture to use at 6:1 before resolution losses become too large.

Certainly the 38/2.8 Olympus is a prime contender.

If you want a little more "budget"... keep an eye out for a 28/4 or 35/4 Schneider Componon.

The 40/2.8 Apo Componon HM is also superb. But they are no bargain. However Adorama has sold quite a few on Ebay that were mounted in a "fixed" f2.8 barrel. These sold for a much more modest price. Perhaps they has more sitting on a shelf somewhere.

Peter M. Macdonald · Post by **Peter M. Macdonald** » Tue Jul 21, 2009 10:36 am

The other thing to keep in mind is that the older, manual aperture, version has an RMS mount, so that it is easy to adapt to almost any bellows system on just about any camera. The newer version has the Olympus OM mount.

Harold Gough · Post by **Harold Gough** » Wed Jul 22, 2009 12:28 am

rjlittlefield wrote:Harold, do you have any data on how the two versions of that OM lens compare?

People occasionally ask me, but I only have the f/2.8.

The optical designs are different -- 5 elements versus 6 elements. My f/2.8 performs best wide open, almost as good at f/4, and noticeably softer at f/5.6. I'm a little worried that the f/3.5 will have the same pattern, but starting at its smaller aperture. If that's true, then the f/3.5 would have somewhat lower resolution for stacking applications.

I am unaware of any comparisons. I found it difficult enough to find brochure or booklets including the later ones, let alone all four.

There may be something useful here:

http://www.mir.com.my/rb/photography/ha ... tm#38mmf28

http://olympus.dementia.org/eSIF/om-sif/lensgroup.htm

The forum to search is:

http://photo.net/olympus-camera-forum/

Harold

ChrisR · Post by **ChrisR** » Thu Jul 23, 2009 3:17 pm

My local high street photo shop, surprisingly, has the 20/2 for GBP £500. I couldn't quickly see how to use it at all on non-Olympus bellows. Doesn't it stay wide open, or is there a button to shut it?

The Manual Focus 28mm 2.8 8 element Nikkor wide angle is reported as being good, either way round. I know it's retrofocus, but aren't all those ELWD scope lenses too?

The 20mm 2.8 is supposed to be OK too, but at full aperture, reversed, its contrast is low and there's a hot spot in the middle.

rjlittlefield · Post by **rjlittlefield** » Thu Jul 23, 2009 7:28 pm

ChrisR wrote:Doesn't it stay wide open, or is there a button to shut it?

There is a button, but it's a spring-loaded DOF preview, no built-in latch. On the other hand, the auto-aperture mechanism is so simple that it would take about two minutes to bend a paperclip to hold it activated. On the other other hand (a third one?), the Olympus auto bellows is not very expensive (compared to the lenses...), it does have a manual stop-down lever, and it's easily adapted to fit most cameras. If you're not happy with Olympus-to-whatever mount adapters, then take advantage of the design that the rear standard of the bellows is just a cylindrical sleeve with a holding screw run in from the side.

--Rik

Edit: correct word: "auto-bellows mechanism" --> "auto-aperture mechanism"

Harold Gough · Post by **Harold Gough** » Thu Jul 23, 2009 10:38 pm

The 20mm f2 and the 38mm f2.8 have the same issues for attachment to non-OM cameras/tubes as does any other OM lens e.g. the 50mm f3.5 macro.

Harold