Race - barrel

Gerd · Post by **Gerd** » Fri Sep 01, 2006 2:06 pm

this is a widespread freshwater ciliate, Coleps hirtus,
always fast swimming and hard to track under the cover glass....
Objective 63x oil, flash, Pentax DSLR
Thanks,
Gerd

Ken Ramos · Post by **Ken Ramos** » Fri Sep 01, 2006 2:21 pm

Excellent shot Gerd. I like to sit and watch these guys feed, they are quite ravionous. Thanks!

Mike · Post by **Mike** » Fri Sep 01, 2006 3:56 pm

Hello Gerd,

It sure looks as though your DIC is working quite well - this great shot of coleps and the earlier shots of the rotifers.

How did you get coleps to pose for the shot? Typically they are moving rapidly somewhere out of the FoV!

I might be mistaken but I think there will be another coleps in the world relatively soon - the mid point appears to be get ready to split.

Great work as usual and congratulations on your succes with the DSLR. I'm getting closer with my Nikon D200 but haven't reached a satisfactory level as of yet.

All the best,
Mike

Charles Krebs · Post by **Charles Krebs** » Sat Sep 02, 2006 12:08 am

Gerd... really nice DIC images!

This is the first I've seen you mention the Pentax DSLR. Any thoughts about how it compares to the Coolpix you were using? Did you have any problems setting it up?

Gerd · Post by **Gerd** » Sat Sep 09, 2006 1:48 pm

Hello Mike, hello Charlie,
please apologize my late response and thanks for your kind comments.
When i check my specimens for ciliates i have a easy to do procedure
(thanks to Sebastian for his tips ! ) : when i come home, i shake the vials with the water
specimens and put the content into a bigger glass. Now i put some coverglasses onto the
water surface. Now i have time enough for drinking some coffee and washing hands and so on.
After some time (30 min. to 12 hours) many ciliates and algae will settle on the swimming coverglasses.
They will build housings and at least a three dimensional habitat. In this small habitat cilates move
much more relaxed than in a water drop taken with a pipette. Coleps moves more slowly and often rests
between the three dimensional particles of the micro habitat.

Adapting DSLR: as you may know, i work with a Leica infinity corrected microscope. Optical correction is
widely done behind the tubus lens, so the picture is directly projected onto the CCD.
The deciding difference to the Coolpix is the missing glass between the microscope objective
and the camera CCD. The light has to pass the eyepiece and the camera objective as well.
Lots of reflections on every lens, you don't need. And the CCDs are much bigger in the DSLRs.

My adaptor works with a tilting angle of 90 degrees, so camera handling is as usual and you
can look at the control monitor directly.
The adaptor is registered at the German Patent Department (www.dpma.de), the number is :DE202005013948U1 as
a petty patent.
Thanks,
Gerd

PeglegOS · Post by **PeglegOS** » Sat Sep 09, 2006 2:07 pm

oooooo Gerd, I want one of those......

Charles Krebs · Post by **Charles Krebs** » Sat Sep 09, 2006 10:36 pm

Very nice work Gerd!

Do you have some fine adjustment to make the camera parfocal with the eyepieces?

Also, with flash there should be no problem, but do you notice any shutter induced vibration when you do not use the flash?

And my last question... how do you feel the image quality compares to the pictures you were making with the Coolpix?

Gerd · Post by **Gerd** » Tue Sep 12, 2006 6:43 am

Hello Charly,
yes, there is a fine-thread on the adaption ring at the scope side (bottom of adaptor),
which fits into the bottom block of the adaptor block. You can adjust the space between the trinocular
tube and the adaptor block here.

Yes, there is shutter inducted vibration, you have to avoid some critical exposure times.

In my opinion, the image quality is much better than with the coolpix. First, some lighting conditions
had ring artifacts, then the images are much clearer due to the loss of glass surfaces, more pixels within a bigger ccd
makes the image quality much brighter.
And working with RAW files gets additional enhancement too.

Thanks,
Gerd

Charles Krebs · Post by **Charles Krebs** » Tue Sep 12, 2006 8:43 am

Gerd... thanks for answering all the questions.

And working with RAW files gets additional enhancement too.

Yes! While I don't have much problem using jpegs with other lighting methods, I have found the RAW format to be very valuable with DIC and cross polarization.