Elementary help on photomicrography?

A forum to ask questions, post setups, and generally discuss anything having to do with photomacrography and photomicroscopy.

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SutherlandDesmids
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Elementary help on photomicrography?

Post by SutherlandDesmids »

I'm not sure if this belongs here or in the beginner's section. I should have access to a trinocular Nikon Optiphot some time in the future if all the details are sorted.

An obvious adjunct to serious work is the ability to take reliable photomicrographs at all powers, especially as phase contrast may even make some simple cytological investigations possible.

The amateur literature is enormous and slightly challenging to the beginner. Unfortunately some background with photography is assumed -- however, my old botany teacher and great friend used a Polaroid microscope camera on a 1930s microscope. Apart from the comparatively primitive fixed lens pocket camera my family has never really taken a serious interest.

I've undertaken a little research, but there is a great deal left to do. For one thing, I am not sure which trinocular head I shall have - whether it's of the full transmission to either eyepieces or camera variety or of the variety admitting of a slight transmission to the eyepieces with the majority going to the camera (the Optiphot ratio is 18:82). The latter is, as I understand, the more desirable as it admits of focussing the photomicrograph through the eyepieces provided that the system of adapters is parfocal with the eyepieces.

As I understand it, this would not have been a problem if we had access to the original setups, but I assume parfocality varies with the endless supply of adapters on the internet.

As I understand it a DSLR is preferred. When original set-ups can be obtained, I understand that a sensor equivalent to 35mm film is best, but I really am at a loss how to begin. Recommendations would be welcome. The subject of adapters is also one I am most unsure about and need help. There are forests of them on the Internet and of course their suitability depends on the camera chosen.

Lastly, I understand that using the microscope illumination is at best rather unsatisfactory, as the shutter and the mirror introduce vibration and the delay renders catching a flying flagellate on the hop pretty much impossible and that it is better to substitute a xenon-arc flash-gun somehow rigged, typically with fibre-optics, to provide illumination.

I presume the shutter is somehow put out of operation as I imagine the principle with a static subject is to compose and focus the image, extinguish the microscope illumination and then provide an intense burst of light for a brief moment that will suffice to activate the sensor, but I could be wrong.

This of course defeats completely the idea of catching a moving organism or passing cytological state, so I must have misunderstood -- there must be a way of instantaneously activating the flash. I believe I half-remember a reference to timing the opening of the shutter within a certain limit and firing the flash at the appropriate time.

Unfortunately I am a botanist, not much of a machinist. As I live in a very remote part of Scotland I can't simply bail out and impose on someone to set up a system for me for a fee, but I would be most grateful for practical advice and help, though I fear mostly theoretical at this stage. Once I have handled the instrument for a few days practical support can be more possible.
Patrick J.K.C. Gray

ChrisR
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Post by ChrisR »

I'm not the best person to answer, Patrick, but I'll set the ball rolling.

First a question, will you be using the camera for anything else, such as normal photography?


Someone will correct me if I'm wrong:
You would normally use a projection eyepiece, but the only useful Nikon one is a 2.5x, which is designed to cover 24mm x 36mm.

You only really need an APS sized sensor, but the Projection Eyepiece would be too much magnification. (Olympus made an expensive 1.6x but it wouldn't suit).

As I understand it, you can remove part of the normal trinoc tube, and place the camera lower, and project directly onto an APS sensor, while retaining parfocality with the eyepieces.

Cameras as you say vibrate; mirrorless cameras less so. Although you can avoid the mirror vibration interfering with the actual exposure, there is still the shutter. You can do something about that ( with "EFSC") on say, many Canon DSLRs, (not all), but something mirrorless and with a truly "silent" shutter, would seem a better choice.

Something like a Sony A6300, though I don't have one.
One aspect you'll wish to know about is "tethering" where you control the camera from a computer.
Again - others will know more than me but Canon DSLRs are better than many.

I'm slowly putting together an Optiphot, and may have a duplicate phase objective, I'll have to check. But you'll probably get yours all together?
Chris R

SutherlandDesmids
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Post by SutherlandDesmids »

My sincere thanks for your reply. I will answer your question and hopefully supply a little further information. So far as I know I will receive a set of phase objectives, but it is deeply kind of you.

The camera is not meant for regular photographic work, but only for microscope use [as I am sure you will understand, it's not possible to study everything -- I've chosen to concentrate on the desmids].

If this helps, I need a set-up both reliable and intended for repeated daily use at high powers. The more stable the better. I intend to connect it to a good laptop with the intention of allowing image-stacks to be stitched for a planned photographic record of species and varieties, growth-forms (Janus-forms and so on) and aberrations.

I've contacted Mr. Charles Krebs, whose set-up for a Nikon research stand is depicted on this forum, but I would be tremendously grateful for any and every piece of advice.
Patrick J.K.C. Gray

JH
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Re: Elementary help on photomicrography?

Post by JH »

Hi

This is one example of an Optiphot trinocular head:
http://www.photomacrography.net/forum/v ... 108#206108

If you can get hold of the empty tube it will be ready for Nikon cameras. For other brands (I use Canon 5D II and Canon 6D) you need an adapter. This setup was made for 24x36 film size, but there is no problems using a smaller sensor than 24x36.

Whit my trinocular head I have 100% camera or no camera. This is probably not the best solution for moving subjects.

I use live view and look on a computer screen before using the shutter remotely.

If you need parfocality you can -for small differences in focus- adjust the eyepieces so they and the sensor are in focus at the same time.

Hope this helps

Best regards
Jörgen Hellberg
Jörgen Hellberg, my webbsite www.hellberg.photo

ChrisR
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Post by ChrisR »

Well, full frame should give you a small improvement in eg noise, colour differentiation and brighness dynamic range. A full frame camera with a relatively low pixel count (larger pixels) would theoretically suit.
But mirrorless ones (Sony) are really expensive.
A Canon 6D would be an easy choice, but with a mirror.

I'd probably go for a Sony 6300 (aps sensor), but haven't really looked into it.
Be sure to research "tethering" options.
Remember electronic shutters don't "wear out"!
If your sensor is smaller than a projection eyepiece is designed for, then of course you're only getting the middle of the field.
You won't need to worry much about having enough Mpixels inthe camera, because the resolution you get at high magnifications isn't actually very high compared with the pixel size.

If you do use a "normal" nikon trinoc, and projection eyepiece, with other than a Nikon camera, you will as noted above need a slightly different length of tube than the official Nikon one.

A secret I've been harbouring for long enough to buy a few, is that the Pentacon microscope adapter happens to be suitable. Here's one:
Image

What you have there is a M42 (common thread) at far left, which goes to the three peculiar 40mm-ish size tubes they use, to the gubbins on the right designed for a microscope - which you don't need!
Any camera to M42, is easy, then the happenstance is that the tubes they use, fit quite neatly into the top of the standard Nikon trinoc tube.
The whole tube sets sell for $15 to £50 including the vital part which is the M42 adapter. This "as new" set was a £20 bargain. Further sets of the ~40mm tubes often come with undesirable Exacta end adapters, with "Ihagee" on them, very cheaply. You can of course extend the M42 tube to suit as well, they're cheap as chips.
Ihagee/Exacta, EG this one currently. I repeat, this does NOT have the vital M42 adapter, but the three central tubes fit the Pentacon set.:
Image
Chris R

SutherlandDesmids
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Post by SutherlandDesmids »

My sincere thanks to you all. Some updates -- I have very kindly been given a Nikon 5x photo eyepiece and a UFX photographic attachment stripped out and rendered light-tight, in effect a tube which happens to be of the ''correct'' length so that a Nikon photo eyepiece will project a real image at the level of a Nikon mirror-box SLR camera.

I believe that a mirrored full-frame Nikon DSLR would be a literal replacement, however a mirrorless camera would serve to remove vibration. I am aware the sensor is rather nearer the flange, but do not know if this signifies.

However, mirror vibration is the least of my worries, apparently, as shutter-shock is just as much of a worry. There are a few Nikon full-frame DSLRs that possess EFSC, but the cost is now prohibitive (we are getting near to the cost of a microscope fitted out for DIC in some).

It is certainly possible to obtain a more affordable solution, but greater modifications and greater skill are required. The cowards' way out, if you like, seems somewhat attractive, if I could persuade a fellow Nikon user to fit up an adapter for a supplied camera, but I will eat my hat if that's good form. Still, the offer is there!

That, in effect, is what AmScope and LMScope offer. The former is cheap, but apparently inferior. LMScope's adapters are very considerably more expensive, but I know nothing of the quality --

https://www.lmscope.com/de/produkte.html [English available]

The convenience of the LMScope option, if quality was not only tolerable but actually very good -- as algal work in the broad sense extends to a great deal of high-power oil immersion and high dry work -- , is a consideration, but further advice is welcome.
Patrick J.K.C. Gray

Alan Wood
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Post by Alan Wood »

Patrick

There are lots of adapters on eBay for using Nikon lenses (or your UFX) on Canon EOS cameras.

Then you could use a second-hand full-frame EOS 5D Mark II or 6D or a new 6D Mark II, depending on your budget. With Live View the mirror is already raised and the shutter is already open, and the exposure is started electronically, so no vibration.

You can use the free EOS Utility program to tether an EOS SLR camera to a computer, so you can easily focus, adjust exposure and adjust white balance.

Alan Wood

Pau
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Post by Pau »

I have very kindly been given a Nikon 5x photo eyepiece
5X projective is way excessive even for full frame sensor, it's intended for medium format cameras, the right secondary magnification for FF with this kind of microscopes is 2.5X (1.6X for APSC and 1.2X for 4/3 but you wont find a Nikon projective for them). A Nikon 2.5 CF photo eyepiece is easy to find at the used market.

Another option is to use a CF 2X (rarer and so more expensive) and a APSC camera.

I concur with Chris and Alan, if you go for FF without breaking the bank, Canon is more convenient, I've used the 6D and it's very adequate at the microscope
Pau

Ichthyophthirius
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Post by Ichthyophthirius »

Hi Chris,

I would be interested in a picture of your adaptation. Sounds interesting.

Regards, Ichty

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