Macro question

"Tom Reese" wrote in message
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"-xiray-" wrote in message
...
On Tue, 30 Mar 2004 16:22:26 GMT, "DR" wrote:

I have a Canon EF 50mmf2.5 macro lens but would still like to get a
little
closer -- should I get the
1-1 life-size converter or could anyone recommend the 12 or 25mm
extension
tubes? (I could also
use these with other lenses) David


Have you tried a ring adapter that allows you to mount your lens in
reverse? Pretty effective... except that the camera has to be really
close to the subject.


I'm not entirely familiar with the Canon system but don't you lose all
control of the aperture when you reverse the lens? In my experience, lens
reversal is only really useful for copy work or with a bellows.

Tom Reese

In my old manual Konica system I had ring that allowed you to reverse a lens
on the front of another so you still had the aperture control in the lens
attached to the camera. This allowed you to, for example, mount a 100 mm
lens on the camera and a reversed 28 mm lens on the front of that.

I found that system had very limited range of focus so it was very difficult
to use. It would give good pictures, but the inconvenience resulted in it
being seldom used and I have never bothered to put together a similar system
for my Canon lenses. (The filter size of my lenses are different so the
original reversing ring won't work without a series of adapters.)

In any case I prefer to use a true macro lens and combine it with extension
tubes if I need to get closer.

In response to the earlier question, I would not waste my money on either
the 12 or 25mm Canon extension tubes but get a set of Kenko extension tubes.
That gives you three different length tubes you can use independently or
mixed together to give a much wider range of use. Much cheaper too and
since there is no glass in an extension tube optical quality is not a
question. You just need an empty tube that seals out light, is matte black
finish inside and maintains the electronic connections between camera and
lens.

Scott Elliot

"Scott Elliot" wrote in message
newscsmc.4874$uN4.893@clgrps12...
In my old manual Konica system I had ring that allowed you to reverse a
lens
on the front of another so you still had the aperture control in the lens
attached to the camera. This allowed you to, for example, mount a 100 mm
lens on the camera and a reversed 28 mm lens on the front of that.

I found that system had very limited range of focus so it was very
difficult
to use. It would give good pictures, but the inconvenience resulted in it
being seldom used and I have never bothered to put together a similar
system
for my Canon lenses. (The filter size of my lenses are different so the
original reversing ring won't work without a series of adapters.)

those rings are still available and they're relatively cheap. Photography
wise, they might be the most fun you could ever buy for $8. In my
experience, the reversed lens on the front of the camera has to be fast to
avoid vignetting. The rule of thumb is focal length of the rear lens divided
by focal length of the reversed front lens equals magnification. For example
a 50mm f/1.4 reverse mounted on a 200mm f/4 would give you 4 times life size
magnification on film and even greater with the digital factor. I have found
that my f/1.4 lens gives me some vignetting so I use a small extension tube
to get rid of it. The front lens can be an old manual lens or even a screw
mount. The key factors are it has to be fast and the aperture has to be wide
open. The rear lens aperture and camera metering will work normally with
this set-up.

Adorama calls this gizmo a "macro coupling ring" and sells them for $8 each.
B&H calls it a "macro coupler" and sells them for $7.95 each.

Tom Reese

I added the 25mm tube for now with my 50f2.5 EF macro and that seems to be
doing the job .... I think eventually I would like to upgrade to the 100USM
EF Macro for 1-1 conversion with AF/Manual simultaneous focusing ... thanks
to all the replied/ David