Direct comparison of eyepieces between camera & 'scope

[mrsonchus]

Hi again - here are some very interesting, possibly even disturbing, certainly illustrative image comparisons from different eyepieces used in-between my Canon EOS 1200D and my 'scopes photo-port. As mentioned in an earlier post, the eyepieces sit in a chamber within the camera->microscope adapter...
I've read that a smaller magnification eyepiece will give a larger FOV than a larger one and that a so-called 'photo' eyepiece (aka 'projection' eyepiece) is somehow superior to a 'normal' eyepiece such as the x10 fitted in the monocular tube of my 35yr old Swift microscope....
Well, I just had to try to actually find out - I bought a Meiji x2.5 'photo' eyepiece to replace the old x10 from my Swift 'scope that I have been making use of in the phototube adapter connecting my camera (DSLR) to my 'scope's trinocular-tube that has featured in my earlier posts on this subject.
Expecting great things I slipped the (not inexpensive) Meiji x2.5 into the adapter and.... here are the results compared to the x10 I was using - you be the judge. Personally I don't think the increase in FOV is very impressive or indeed particularly useful. The Meiji clearly shows superior chromatic correction but you really do need to 'pixel-peek' to notice!

First the Swift's x10

Here's the FOV of the Swift's x10 'normal' eyepiece

websize_2_Swift_eyepiece_with_x20_objective.jpg (131.41 KiB) Viewed 9401 times

Next the Meiji x2.5 'photo' eyepiece - it seems very dirty even after cleaning - it may be on the inside, I may have to return it!

Slightly larger FOV than the x10.....

websize_2_MJ_eyepiece_with_x20_objective.jpg (142.47 KiB) Viewed 9401 times

Now for a surprise - I tried it with NO EYEPIECE and got this, the largest FOV of all!

This I think is the best image - at least with the x20 objective...

websize_NO_eyepiece_with_x20_objective.jpg (131.82 KiB) Viewed 9401 times

Well, before you start to scream uncontrollably, as I nearly did - the x4 objective couldn't quite get near enough to the slide for the no-eyepiece option to focus - it didn't work with the x4 objective although adjustment of the camera->objective distance may fix this, but that may then reduce the FOVs? (does anybody know?). I may test this I may not - still trying not to weep every time I look at the new Meiji x2.5 'photo' eyepiece!

An interesting, time consuming and still slightly ambiguous result but I had to try...

I hope this helps rather than hinders.

[Crater Eddie]

Food for thought indeed. Thanks very much for posting this.
I'm going to have to think about this.
CE

[mrsonchus]

Food for thought indeed. Thanks very much for posting this.
I'm going to have to think about this.
CE

Same here - it's raised more questions than it's answered for me too...

[mrsonchus]

A thought - I don't know if it's relevant (I suspect not) but my 'scope - the one used for the tests, has infinity corrected objectives. I may try the same comparison tomorrow using my old Swift 160mm tube-length (DIN) 'scope to find out, then again I may not feel like it...

[mrsonchus]

I've had these spores from a fern in my garden for about 6 weeks now, kept in pure glycerin.
I think the spores have started to 'sprout' - the filamentous-looking structures originate from the spores I think?
I think the plate-like structures may be the start of a fern's gametophyte - not sure though, I'll have a read.
It would be great to try to actually grow-on the fern spores....
Oops - forgot to include picture of the other structures - sorry to go off-topic but here they are as seen by the x2.5 Meiji eyepiece:

Strange things going on here....

websize_fern_spores_sprouting.jpg (332.08 KiB) Viewed 9394 times

[gekko]

Thank you for posting this. Very interesting indeed.

[rnabholz]

Interesting, I am considering imaging options and appreciate the data point.

Thanks

[mrsonchus]

Well, I've cleaned the grime and speckles from the Meiji and have decided what I'm going to do. The Meiji is a beautiful and well matched choice for my system and I'm going to keep and use it. The x10 can go back where it lives in the Swift Collegiate 400 - this is up for sale now - cheap if you're in the UK.
I really want to keep the x4 objective capability too and am also content with the reasonable FOV that the Meiji gives - the next step down to a 1.9 Meiji is nearly £300! The Meiji 2.5x therefore is my choice and I'm sticking with it and concentrating on what I enjoy most - preparing and mounting specimens. Hardware-testing is fun but it's not why I bought a 'scope - so I'm going to carry on now with my next mini-project, the use of the aniline blue stain and maybe even another attempt at the Fast-Green and Safranin stains too...
I hope the above info helps some to think about their choices as as it has helped me - sorry I can't come up with anything definitive - I don't have the expertise to be able to I'm afraid.

[Crater Eddie]

Sometimes you just have to pick one and run with it John. Thanks for showing us this, it is very interesting.
CE

[gekko]

I also meant to say (but forgot) that all your images above are very good, although I think the one with the Meiji lens was my favorite.

[mrsonchus]

I also meant to say (but forgot) that all your images above are very good, although I think the one with the Meiji lens was my favorite.

Thanks, yes I agree, the Meiji (discounting the speckles) is just a more satisfying image to my eyes. I see it as better clarity, better colour and it definitely has superior chromatic correction. By 'better' I am being subjective, the CA correction is I'm sure demonstrable.

Thanks for everyone's very kind and positive comments, they really have helped me with my microscopic exploits - having a great time!

[vasselle]

Bonjour
Très bon commentaires sur objectif 2,5 X.
Et vos photos sont très bonnes.
Cordialement seb

[The QCC]

The Meiji 2.5x PE is the wrong eyepiece for your APSC camera. The 2.5x is meant for full frame sensors.
Your APSC sensor should have approx. a 1.6x magnification.
Using a standard 10x eyepiece is way too large for your camera.

I use a Meiji 2.5x with my Canon 5D MkII and it fills the sensor perfectly.
I use a Nikon PL 2.5x with my Canon XS and the image is much too big. Requiring the camera to be placed a greater distance from the eyepiece to just fill the sensor..

[mrsonchus]

The Meiji 2.5x PE is the wrong eyepiece for your APSC camera. The 2.5x is meant for full frame sensors.
Your APSC sensor should have approx. a 1.6x magnification.
Using a standard 10x eyepiece is way too large for your camera.

I use a Meiji 2.5x with my Canon 5D MkII and it fills the sensor perfectly.
I use a Nikon PL 2.5x with my Canon XS and the image is much too big. Requiring the camera to be placed a greater distance from the eyepiece to just fill the sensor..

I know the x1,6 will give me a larger frame but it's nearly £300 and I can't spend as much on the eyepiece as I have on the EOS1200D - still, I'm pretty happy with my setup now. Not perhaps so much the 'wrong' eyepiece as merely a sub-optimal eyepiece in terms of % frame coverage....
Here's some handy comparison info:

Sensor vs photo-eyepiece mag

websize_photo_eyepiece_image_sizes.jpg (72.54 KiB) Viewed 9283 times

websize_photoeyepiece_mag_vs_cam_sensor_size.jpg (136.75 KiB) Viewed 9283 times

Hope this helps a bit.

[The QCC]

The Meiji MA986 1.9x adapter is available for much less than £300 .
I found these two sites with competitive pricing
http://www.microscope.com/accessories/a ... -1-9x.html
http://www.opspe.co.uk/IMG/slr_attachment.html

[mrsonchus]

The Meiji MA986 1.9x adapter is available for much less than £300 .
I found these two sites with competitive pricing
http://www.microscope.com/accessories/a ... -1-9x.html
http://www.opspe.co.uk/IMG/slr_attachment.html

The UK site is offering the MA x1.9 for under £200 - I wish I'd seen this earlier....
Thanks for the info.