photographing slides

[Eric or Pat Metzler]

Hi all,

I want to add a bit to what Ken wrote.

A stereo scope will never take a high quality photo because of the low numeric aperature of the objective.  Quality on a stereo scope is of little use.  A compound microscope or equivalent is nearly required.  A quality objective or lens is required.  Low power compound lenses have very low numerical aperature, thus they need to be of the highest quality - very expensive.

The condensor to focus the transmitted light through the specimen is excellent for transmitted light, but reflected light photography will also work, with a completely different perspective - and no condensor is needed.

I use a devise made by Leitz, called an Aristophot.  They can be purchased used.  I use a regular camera with a long bellows and Leitz micro-lenses.  The Leitz lenses are very high quality, and older ones can be purchsed used for less than $100.00 each on eBay.  The transmitted light, should be properly focused with even illumination across the specimen, is critical.

For a camera, the larger the size of the film the better.  A 35 mm camera is OK, but the process of making a print which is an enlargement takes some care and a good technician in a good lab.  Work with the technician to explain what you want.  A 4" x 5" camera gives a negative that doesn't have to be enlarged, therefore less grain.  You still need a good lab.

Or you can go digital and ignore the film altogether.

Because of the high magnification and long bellows, I have very long exposures - up to several seconds.  For this, the regular camera shutter makes too much vibration.  Insert a leaf shutter in the light path and use that by first opening the camera shutter before exposing the film through the leaf shutter.  Make sure you can lock up the mirror of the camera, and kill all vibrations.  A concrete floor with a very sturdy table is best.

Also, don't close down the f stop any more than absolutely necessary.  A f-16 gives great depth of field, but at a loss of clarity.  Most lenses have an optimal f stop.  For my Nikon macro lens, it is F-11.  Learn the  optimal f stop for your lens and use that one.  If you don't know, experiment with several f stops and then examine the negatives - not the photos.  Adjust the light and shutter speed to get the best f stop.

This should get you started.

Eric

from Ken Philip: "Anyone who is conversant with older techniques for light microscopy
should be able to help you set up something like the above. The key
components are the low-power objective and low-power condenser, plus
the appropriate lamp for Kohler illumination. And the objective should
be of high quality."

Hi everybody,

Has anyone on the list ever had any experience with photographing
microscope slides of insect genitalia?  I am in the process of writing up
my thesis on the systematics of a large group of native Austalian moths and
have over a hundred species to illustrate.  So far I've tried using the
optical camera attached to a Wild stereomicroscope and also the same
microscope with a Nikon Cool Pix digital camera just taking pictures
through the eyepiece, with all sorts of combinations of lighting, depth of
field etc.  I'm finding that its very difficult to get clear focussed
images.  I'd greatly appreciate  any advice on offer

Cheers 
Cathy Young
University of Tasmania




 
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