Trinocular Microscope Adaptor ?

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Harald
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Trinocular Microscope Adaptor ?

Post by Harald »

Hi there,
I have a trinocular microscope, and the photoport is 23,2 mm threads.. Is this the same as C-mount ?
I also have one of these aftermarked T-2 to 23,2 mm adaptors (no threads).
When I use this adaptor it´s a little bit "wobbly".. I´ve searched with google but I´m not shure what to search for..
Want to use my EOS 7D on the microscope.

Hope anyone out there can help me :shock:
Kind Regards
Harald

Lier Fotoklubb / NSFF
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Charles Krebs
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Post by Charles Krebs »

Harald,

That's not a c-mount thread.

What model microscope? Can you post a picture of the trinocular head?

Can you provide a link to, or pictures of, the adapter you are trying to use?

Pretty sure we can help you out, but it is necessary to know what you are working with.

SONYNUT
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Post by SONYNUT »

did you measure the outside of male threads?
..............................................................................
Just shoot it......

Harald
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Location: Steinberg, Norway
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Post by Harald »

My micrscope is the AmScope Model No: T230A..
I can provide you with some photos later if you need.

This is my current adaptor:
http://cgi.ebay.com/Microscope-Adapter- ... 805wt_1141
Kind Regards
Harald

Lier Fotoklubb / NSFF
AFIAP / CPS
BGF / GMV
http://www.500px.com/blender11

Charles Krebs
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Post by Charles Krebs »

Harald,

I looked at a picture of an Amscope Model No: T230A, and it appears to have a "standard" trinocular tube. This tube has the same inner diameter as most microscope eyepiece tubes. It is commonly referred to as having a 23mm inner diameter, although the actual diameter of the eyepiece barrel that gets inserted is 23.2mm (the other standard eyepiece tube size encountered is nominally 30mm inner diameter).
The photo below shows your adapter on a microscope. The microscope might not be exactly the same as your Amscope, but the Amscope should have the shiny tube seen as "A". (The photos of the Amscope T230A I've seen have this tube).

At the top, the inner diameter of tube "A" should accept eyepieces (and adapters) that have a 23.2mm outer diameter. The inside top of tube "A" should not be threaded, but smooth! Are you sure that yours is threaded? An eyepiece or your adapter should make a "slip-in" fit into this tube (at "C"). The actual "fit" varies somewhat. Sometimes it is a little "snug", other times it may feel a little too "loose". (Most of the older SLR camera adapters actually clamp around this tube rather than inserting into it like an eyepiece). If your "slip-in" adapter wobbles too much with your camera attached I would suggest you shim up the connection so that is makes a nice "snug" fit. (Depending on how sloppy it is, you might be able to do it simply with a narrow strip or two of tape).



Image

Harald
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Post by Harald »

Hi there Charles,
I think I go for your proposal and use some thread tape, the one plumbers use. This is very thin and I think good for this use. Thank you for your time :D
Kind Regards
Harald

Lier Fotoklubb / NSFF
AFIAP / CPS
BGF / GMV
http://www.500px.com/blender11

Mitch640
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Post by Mitch640 »

Harold, I use to own an Amscope. The adapter you have should fit into an eyepiece hole fine, with no wobble. Mine did.

I also bought this one for the trinocular tube.

http://cgi.ebay.com/Microscope-Adapter- ... 2eb3b3cb82

It goes on the outside of the tube and clamps to it. Then you drop an eyepiece lens into the hole inside, then you mount the camera on the T-ring. Cheaper, works great. In fact, it worked better than the more expensive one.

Harald
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Post by Harald »

Oooops :?
I´ve searched the box the microscope came in and I found the tube :oops:
Now it all fit nicely together :P
Hopefully I will do some images this weekend.
Thank you for your time and help folks :D
Kind Regards
Harald

Lier Fotoklubb / NSFF
AFIAP / CPS
BGF / GMV
http://www.500px.com/blender11

Mitch640
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Post by Mitch640 »

By the way, the adapter you have, says it is 2x. But if you read the fine print, it is closer to 10-12x.

Charles Krebs
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Post by Charles Krebs »

Mitch,
By the way, the adapter you have, says it is 2x. But if you read the fine print, it is closer to 10-12x.
Your are conflating two entirely different things. The description given at the link above for those adapter says:
"Canon CMOS sensor with 2x lens equivalent to 12x~15x eyepiece (varys by CMOS sizes)"

What this means is that the adapter is designed to provide a 2X magnification on the camera sensor. A 2x magnification onto a DSLR camera sensor records a view approximately equal to what the observer will see if they are looking through microscope eyepieces of roughly 12X to 15X. The description correctly states that this will be dependent on camera sensor size.

No adapter designed for SLR or DSLR cameras that I am aware of provides (or at least should not!) anywhere near a 10-12X magnification onto the sensor. The image results would be terrible, and you would be recording a very tiny amount of what is seen through the eyepieces (in the neighborhood of 12%). Any photomicrographer I know would, and should, find this totally unacceptable. A magnification of 10-12X onto the film/sensor plane would be acceptable if you were photographing onto 5x7" (or possibly 4x5") sheet film!

Mitch640
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Post by Mitch640 »

Here's what my experience was. If you use this adapter, with the 2x lens built in and connect it to a T1i, you will get approximately the same size final image as if you use the other adapter, that does not have any built in lens in it, and then stick your 10x eyepiece lens in the hole and attach the T1i. Not exact, but very close.

Charles Krebs
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Post by Charles Krebs »

Mitch,

Yes, it is entirely possible to get a 2X on sensor magnification by using a 10X viewing eyepiece with the adapter you linked to above. When the microscope is properly set-up and properly focused, this is accomplished only if the 10X viewing eyepiece aperture is actually situated considerably higher than was designed for visual use (in relation to the intermediate image location as per: http://www.krebsmicro.com/pdf/trinoc_a3.pdf ).
Doing so, I have seen results that were quite good, and results that were quite bad. I know of no way to predict the outcome in any given case unless you try it. But the key point I was trying to make is that when used in this manner the magnification on sensor is not the 10X that is marked on the eyepiece, but (if done "properly") much less, more in the 2-2.5X range.

So when you say:
... says it is 2x. But if you read the fine print, it is closer to 10-12x
it creates unnecessary confusion, because you're comparing apples (magnification on sensor) to oranges (magnification as seen through the eyepieces).

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