Does this look like DIC?

[Sam236]

It is hard to find the appropriate DIC condenser prisms on Ebay, So I bought the closest one I can find. the DIC prism is for older BH reflect microscope. From the Olympus website I learned that for reflect microscope, Objective DIC prism shears the light traveling down and recombine after the light hits the specimen and going up.

I already have the BH2 Objective DIC slider for recombining the light,
so I thought i will try these older Dic prisms as the condenser DIC for shearing.

It took me almost half hour to align the Dic prism, here is what it look like:


the prism is for Mplan 100x with NA 0.9. my Splanapo 40X with NA 0.95, doesn't show much difference, but Splanapo 20 with NA 0.70 showed something different and similar to pseudo 3D effect.


after almost 1 hour of testing, I took a few photos of what I think are closest to DIC effect. I have no idea if this is even close to the real Dic effect, please give me some advise:




I am using Sony SLT-55V and there is a bright light always shows in the center, is there anyway to make it disappear?




Sam

[Sam236]

I found this description from Nikon's website:

"in many cases, a gradient of light appears across the entire field of view when observing DIC images. This occurs in addition to the presence of light and dark intensities at opposite edges of the specimen, and is due to a broad and indistinct field fringe artifact produced by the optical system. Microscopes having well-matched optical components maximize the size of the field fringe, which can become so broad and evenly distributed that the entire field appears a uniform medium gray color. In most cases, however, some evidence of the fringe remains, and the viewfield exhibits a shallow gradient of light intensity (medium to light or dark shades of gray) from one peripheral edge to the other. This artifact is inherent in a particular optical configuration and should be ignored when observing and collecting images of DIC specimens."

since my setup has two dic prism that is not well-matched, a distinct
fringe appears in the center of the field of view, and the distribution of the gray color is not uniformed.
Just a word of warning to all microscopic beginner who are eager to find the Dic component for their microscope, it is very risky to buy Dic components that are not designed for your microscope, most of time the result is not good. I did see some effect of DIC which is quite exciting, but I will keep looking for the appropriate DIC prisms which I believe will deliver a far more superior DIC view.
Good luck to all who are still patiently waiting for the DIC components.
Sam

[rjlittlefield]

Silly question, but have you checked to see if the bright spot disappears when you remove the two DIC prisms and make no other changes?

Just from the appearance in these two images, I'd give pretty good odds on a spurious reflection someplace in the other lenses and tubes.

--Rik

[Sam236]

Silly question, but have you checked to see if the bright spot disappears when you remove the two DIC prisms and make no other changes?

I removed two DIC prisms, the bright spot is still present. it is also showing in normal bright field and in Darkfield, I changed the settings in the camera, but that doesn't help.
Sorry for the silly question, I did try to learn everything myself by searching online, and look through the old posts.

I have two intermediates (Mag changer, and fluorescence attachment), that maybe the cause, I will remove them and give it a try again.

thanks for the reply, Sam

[rjlittlefield]

Sorry for the silly question, I did try to learn everything myself by searching online, and look through the old posts.

No, no, it was my own question that I was referring to as probably silly.

I did try to learn everything myself by searching online, and look through the old posts.

I think that's impossible. Certainly it's very inefficient. You're doing the right thing by showing what you've done and asking, now what?

I have two intermediates (Mag changer, and fluorescence attachment), that maybe the cause, I will remove them and give it a try again.

Sometimes you can get a hint by removing the camera and looking into the tube by eye. Any light glinting off the sides is a bad sign.

--Rik

[Sam236]

No, no, it was my own question that I was referring to as probably silly.

I misunderstood, There is a lot more to learn on the theories behind the techniques used in the microscope, and there even more to learn on how to Stack good photographs, long road ahead, and thanks for the advice on the photo eyepiece, I didn't see any light glinting off the sides, central spot light maybe the cause by the adapter that used to connect OM L and the camera body. It has a lens built within.

Sam

[Pau]

The first one looks as DIC, but weak, the last one definitively not.

Your lower prism looks placed too low in the optical train: usually it is placed inside the condenser, and because it comes from a reflected DIC objective I think that its distance to the focal plane must be very small. Try to place it as close to the condenser as possible (a carboard tube or a film canister and its original holder may be adequate to place it raised over your polarizer). The goal is to place the dark interference band at the objective rear focal plane (or close to it if you can't) as explained in the Nikon Molecular Expressions or Olympus websites.
http://www.microscopyu.com/tutorials/ja ... index.html

About the issues with your photoadapter, if you post images of it and more info about its components, maybe it would be easier to understand

Note: The polarizer must be oriented E-W and in your image it seems oblique to the right position (but maybe a perspective error while seeing the image).