centre white spot

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Joss
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Joined: Mon Jun 29, 2015 11:54 am

centre white spot

#1 Post by Joss » Mon Jun 29, 2015 12:26 pm

Hello everyone,
complete beginner to microscope photography. An Olympus BH has come my way, and I've attached a Canon EOS 1100D to it via a phototube, with a 3.3x photo eyepiece. My first attempts show this bright centre spot that you can see on the attached image (the image is a screen shot of what I can see using Live View - the image through the microscope eyepiece is fine). I expect this is a very basic thing, but I'd be grateful for any pointers on how to sort it out.
thanks, Joss
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75RR
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Location: Estepona, Spain

Re: centre white spot

#2 Post by 75RR » Mon Jun 29, 2015 1:41 pm

... the image through the microscope eyepiece is fine).
Does that include the image through the trinocular eyepiece?

See links:
viewtopic.php?f=15&t=882
Zeiss Standard WL (somewhat fashion challenged) & Wild M8
Olympus E-P2 (Micro Four Thirds Camera)

Joss
Posts: 2
Joined: Mon Jun 29, 2015 11:54 am

Re: centre white spot

#3 Post by Joss » Mon Jun 29, 2015 3:13 pm

Yes, if I replace the phototube with an eyepiece lens, the image is normal through the trinocular tube. Thanks for the links.
Joss

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Oliver
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Re: centre white spot

#4 Post by Oliver » Mon Jun 29, 2015 9:50 pm

The bright spot could be due to the reflection of light inside the phototube. once had a similar issue. Closing the koehler diaphragm resolved this (should you microscope have this), alternatively you might want to check if the inside of the tubes are sufficiently dark, to reduce reflection.
Oliver.
Image Oliver Kim - http://www.microbehunter.com - Microscopes: Olympus CH40 - Olympus CH-A - Breukhoven BMS student microscope - Euromex stereo - uSCOPE MXII

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