Connecting a Micro 4/3 camera to a microscope

Starting out in microscopy? Post images and ask questions relating to the microscope and get answers from our more advanced users on the subject.

Moderators: rjlittlefield, ChrisR, Chris S., Pau

zzffnn
Posts: 1896
Joined: Thu May 22, 2014 1:25 pm
Location: Houston, Texas, USA
Contact:

Post by zzffnn »

Yes. It would not work ( and I won't mention it), if it does not. Please see the last 2 photos of my thread for sample photos. I used Sigma 35 mm f 2.8 m4/3 lens and Olympus E-PM2.
Last edited by zzffnn on Sun Apr 19, 2015 5:27 pm, edited 1 time in total.
Selling my Canon FD 200mm F/2.8 lens

dragonblade
Posts: 200
Joined: Sat Oct 18, 2014 11:16 pm

Post by dragonblade »

zzffnn wrote:Please see the last 2 photos of my thread for sample photos. I used Sigma 35 mm f 2.8 m4/3 lens and Olympus E-PM2.
Yes, I saw those two photos before. Great work with the new lens. For the time being, I'll be using the 14-45mm zoom and see how that fares. It's actually well regarded for a kit lens (supposedly better optics than a lot of kit lenses in general) but hard to say how it will perform with this kind of work. A few years ago, I came across a Canon FD 35mm for an absolute bargain price at a camera fair, and I really regret not picking it up. Though I don't know if the extra 5mm in focal length would make it too long for afocal photography.

zzffnn
Posts: 1896
Joined: Thu May 22, 2014 1:25 pm
Location: Houston, Texas, USA
Contact:

Post by zzffnn »

Like Enrico said, your Canon 50 mm macro lens (APSC format?) or Canon FD 50 mm f1.8 (full-frame format) are the best bet. Or your kit zoom m 4/3 format lens at 30 mm.

To convert "full-frame equivalent focal length" (which indicates angle of view) of m4/3 format lens to Canon APSC format lens, you need to multiple it by 1.6 (30mm in m4/3 format = 48 mm in Canon APSC format). And to convert m 4/3's equivalent focal length to full-frame, you need to multiple it by 2.

Canon FD 35 mm (full-frame format) lens is likely too wide and not as good as your 50 mm Canon lenses.

Math details can be found at wiki: http://en.m.wikipedia.org/wiki/35_mm_eq ... cal_length

Edit: sorry, I meant to say "full-frame format equivalent focal length" (instead of "focal length"), which is an indication of angle of view.
Last edited by zzffnn on Tue Oct 21, 2014 3:55 am, edited 9 times in total.

enricosavazzi
Posts: 1474
Joined: Sat Nov 21, 2009 2:41 pm
Location: Västerås, Sweden
Contact:

Post by enricosavazzi »

zzffnn wrote:Like Enrico said, your Canon 50 mm lenses (APSC format) are the best bet. Or your kit zoom m 4/3 format lens at 30 mm.

To convert focal length of m4/3 format lens to Canon APSC format lens, you need to multiple it by 1.6 (30mm in m4/3 format = 48 mm in Canon APSC format). So Canon FD 35 mm is likely too wide and not as good as your 50 mm Canon lens. Math details can be found at wiki: http://en.m.wikipedia.org/wiki/35_mm_eq ... cal_length
Just to make things clear, focal length of a lens remains the same regardless of sensor size of the camera on which the lens is mounted. Only the angle of view at infinity changes. For use as a relay lens on an ordinary 10x microscope eyepiece, the (approximate) optimal focal lengths are:

30 mm on Micro 4/3
45 mm on APS-C
60 mm on full-frame

A Canon 50 mm lens remains a 50 mm lens when mounted on a Micro 4/3 camera. This means that the Canon 50 mm lens is a bit too long for use as a relay lens on a Micro 4/3 camera, and with this lens the camera will image only the center portion of the image circle provided by the eyepiece.

This is not optimal, but it may be usable if nothing else is available.
--ES

dragonblade
Posts: 200
Joined: Sat Oct 18, 2014 11:16 pm

Post by dragonblade »

Recently, Ive been really intrigued by Tardigrades. I really like the way they walk and their whole overall appearance. I hope I find some of these. Ive heard they're very fond of lichen. There's some green algae growing in some of the dams over here. I'll grab some water samples from the algae when I get a scope and hope for the best.

By the way, there is a chance that the Canon FD 35mm might also be a retro focus design (reverse telephoto.) Could this pose any problems when using the lens for afocal photography? Though as it's only a slight wide angle (in 35mm format), there's also a fair chance that it might be a conventional lens design. I'll check google and see if I can find the truth.

Edit: Ive just found out that the older Canon FL 35mm lens is a retrofocus design so it's very likely that the Canon FD 35mm is the same. Any potential issues here for afocal imaging?

Enricosavazzi, with regards to the webpage that you dedicated to using a micro 4/3 camera with a Zeiss microscope, I see a very good visual comparison that you made between the field of view of an Olympus 12mm and the fov of the Sigma 30mm, both looking at a sample specimen through the 10x eyepiece of a microscope. Based on those two images, I did a very rough calculation and determined that the extra 5mm in focal length of a 35mm lens would likely produce too tight a crop for my liking. So yea, I think I'll forgo picking up an old, manual 35mm prime and get the Sigma 30mm instead (if things don't work out with the 14-45mm.)

Post Reply Previous topicNext topic