Adapter for DSLR on Nikon Ci-L microscope

benedictus · Post by **benedictus** » Thu May 25, 2017 10:27 am

Hi,
I wonder if someone could provide me with advice regarding best quality adapters for a new Nikon Ci microscope to a Canon 70D with an APS-C sensor. I am currently using a VariMag II adapter but micrographs show clear chromatic aberration and are soft quit unlike the extremely sharp images seen through the eyepices from high quality infinite lenses (Apo 4x/0.20, Plan Flour 10/0.30, 20/0.50, 40/0.75). I guess the VariMag adapter is not equipped with high quality lenses. Also I cannot get the parfocalization right.

The Nikon Ci has a trinocular head with a 38mm diameter photoport. I plan to do light-field as well as dark-field micrography.

Other suggestions for high res. photo solutions with this microscope are welcome too. I'm prepared to do reasonable investments to achieve my goal.

Cheers

Pau · Post by **Pau** » Thu May 25, 2017 11:24 am

Hi benedictus, welcome aboard!

I can't be more precise because the lack of knowledge about your trinocular head, but being your microscope a wide field model with the primary image full corrected IMO the best arrangement would be direct projection of the primary image on the camera sensor if you can arrange a short enough phototube (just an empty well flocked tube) to project the primary image without any relay optics on the sensor at parfocal position with the eyepieces.
Some members have done it with Nikon Eclipse and Olympus BX microscopes.

Could you post pictures or links to your trinoc head and its phototube mounted and dismounted if doable?

Some examples of APSC DSRLs mounted for direct projection on high end microscopes:
http://www.photomacrography.net/forum/v ... 989#200989
http://www.photomacrography.net/forum/v ... 597#112597
http://www.photomacrography.net/forum/v ... 2446#82446

houstontx · Post by **houstontx** » Thu May 25, 2017 11:27 am

I think the Nikon T-BPA 38mm Adapter used with CI 2.5xA or 5x eyepiece is the stock nikon solution..But not sure.

houstontx · Post by **houstontx** » Thu May 25, 2017 11:30 am

https://blog.noq2.net/wild-m8-phototube ... hting.html

Look at pics 6,7,8 from this link. That Is a solution using the T-BPA adapter

benedictus · Post by **benedictus** » Fri May 26, 2017 2:46 am

Hi pau and houstontx,

THanks for your quick help!

I attach a few photos of my equipment.

Pau, the solution you suggest, is that without optics in the adapter? Is so, that sounds attractive to me because the direct image from the microscope is very crisp. I wonder where such adapters can be acquired..

Cheers

Bent

harisA · Post by **harisA** » Fri May 26, 2017 5:03 am

Welcome to forum.I had a similar problem with my nIKON eclipse 400.The best solution is without using intermediate optics,the objectives you mentioned in your first post will cover an APS sensor without problems.

But there is no plug and play adapter as far as i know.I solved the problem using the following part:
http://www.ebay.co.uk/itm/Phototube-1X- ... SwBLlVaSUo

Be aware that these parts are not of high quality and i had to paint their interior since i had problems with internal reflections.
Also these are only suitable for mirrorless cameras with short flange distances (olympus,sony canon-M where a c-mount to camera mount is available).In case of Canon DSLRyou must throw away the upper part and lower the length of the white phototube and after add a custom made ef adapter.This can be done only if you have aceess to a lathe.
I'm using a sony mirrorless so in my case was an easiest task

Pau · Post by **Pau** » Fri May 26, 2017 5:31 am

is that without optics in the adapter?

Yes, just an empty extension tube.

Your microscope head seems adequate for direct projection.

You need to determine the position of the primary image and its distance to the trino exit flat surface when the microscope is well focused with the eyepieces. A 10X objective is normally the more adequate to do so. Use a high contrast small detail to focus (a dust particle at the slide can do). You can do it with the camera without lens in Live View or with a translucent paper or frosted glass.
-The length of the tube must be this distance less 44mm (flange focal distance of the Canon EF bayonet mount).
-Then you need to make or order a tube with a fit to the trino port (your current adapter mount seems a good model) and a Canon EF mount at the other end. Usually is easier to get it with M42x1 or M42x0.75 (T mount) and an easy to find adapter to Canon.
-You could include a focusing helicoid to fine tune parfocality.
-To prevent vignetting use a wide enough tube, avoid C-mount adapters.
-You also want that the inner surfaces of the tube are well flocked to avoid glare due to reflections. If you use camera extension tubes in most cases they are, if not you can flock them with a material like Protostar.

About magnification:
With this setup you will have on sensor the magnification provided by the objective (and maybe other optical components if present like magnifier changers if you mount them) and it very likely will cover the APSC sensor with high quality image. Maybe with some objectives you could have some vignette or degradation at the corners, just a bit of crop will manage it.
The captured image will be somewhat wider than the visual field

With a 2.5X projective eyepiece like houstontx proposes you will have 2.5X magnification, ie the image will be cropped, much smaller than the visual field. With low power objectives it could provide some more resolution as the objective is able to outresolve the sensor although with less crispness.
With high power objectives this advantage mostly disappears. The only possible advantage over cropping the image at the computer will be less noise

In most cases I will prefer direct projection.

Hope this helps.

benedictus · Post by **benedictus** » Tue May 30, 2017 1:52 pm

Hi harisA and Pau

Thanks for the good suggestions! Now I have something substantial to start from and I do have a good friend with a lathe.

Best wishes