Merismopedia - A Raft Of Cyanobacteria Cells

Mitch640 · Post by **Mitch640** » Sun Nov 27, 2011 6:22 am

"Merismopedia is a genus of cyanobacteria found in fresh and salt water. It is ovoid or spherical in shape and arranged in rows and flats, forming rectangular colonies held together by a mucilaginous matrix. Species in this genus divide in only two directions, creating a characteristic grid-like pattern."

I have installed my new/used Phase Contrast Condenser for the Nikon Fluophot, a very rare item. I do not have any Phase objective lenses for it just yet, but can use the zero position for Brightfield and by turning the dial just off center, I can produce right or left side Oblique lighting, which has the effect of showing the shape of things better than plain brightfiled.

The video link.

1. 40x Nikon Plan Achro.

2. 60x Nikon NCG with a coverglass.

3. 60x Nikon NCG with a coverglass.

NikonUser · Post by **NikonUser** » Sun Nov 27, 2011 7:11 am

Very nice Mitch, video equally impressive. You are getting good results with both the 40x and 60x.

In case you don't know, keep an eye out for a centering telescope eyepiece. You will need one to align the phase rings when you get a phase objective.

Mitch640 · Post by **Mitch640** » Sun Nov 27, 2011 7:17 am

Thanks for looking Tony. I was aware of the centering tool, but have never seen one for sale. Of course, I have never looked either. Is there any other way to do it "manually"? I suppose I should start looking. I'm just ecstatic to have found the condenser, and in not too bad condition either.

NikonUser · Post by **NikonUser** » Sun Nov 27, 2011 7:36 am

They turn up on ebay. Not sure that you have to have a Nikon model, seems to me that any make will work as long as it fits into 1 of the eyepiece tubes.
I tried centering the phase rings with an eyepiece removed (no CT). Supposedly can be done but I found it not possible. The phase rings have to be in perfect alignment for phase contrast.

RogelioMoreno · Post by **RogelioMoreno** » Sun Nov 27, 2011 7:42 am

Mitch,

Nice video!

Nice to hear the phase condenser is in good condition.

Rogelio

Mitch640 · Post by **Mitch640** » Sun Nov 27, 2011 7:50 am

Thanks Rogelio. Yes, the lens turned out to be clear, the "fog" was just the angle of the light and the white background being reflected. It has a few scratches on the paint, but for something around 25 years old, it works very smooth. No binding at all and the iris is easy and smooth to turn. It was very clean.

I do have to retrain my fingers though, and just when I had taught them where all the knobs and adjustments were on the other condenser.

Charles Krebs · Post by **Charles Krebs** » Sun Nov 27, 2011 4:19 pm

I was aware of the centering tool, but have never seen one for sale. Of course, I have never looked either. Is there any other way to do it "manually"?

A useful "trick" is to pull one eyepiece out (or use a spare eyepiece) and carefully hold it up, top to top (eye-lens to eye-lens) to the other eyepiece that is still inserted. Look into the back of the eyepiece you are holding and you can get a very good look at the objective rear aperture. Easy to align phase rings that way.

Mitch640 · Post by **Mitch640** » Sun Nov 27, 2011 4:33 pm

Thanks Charles. I was surfing around yesterday and came upon a page that described how to do it, but I was only paying half attention and now can't find that page again. Your method sounds easy enough. I will give it a try when I buy a PH lens.

NikonUser · Post by **NikonUser** » Sun Nov 27, 2011 5:25 pm

Charles Krebs wrote:
A useful "trick" is to pull one eyepiece out (or use a spare eyepiece) and carefully hold it up, top to top (eye-lens to eye-lens) to the other eyepiece that is still inserted. Look into the back of the eyepiece you are holding and you can get a very good look at the objective rear aperture. Easy to align phase rings that way.

Sounds great, in theory. On my BH2 I have to use both hand to twiddle the 2 centering screws (1 on the right 1 on the left) on the condenser to line up the phase rings. So holding a 2nd eyepiece up against a 1st eyepiece would take some really fancy manipulation on my part.

Mitch640 · Post by **Mitch640** » Sun Nov 27, 2011 5:49 pm

Mine also has two knobs, and they are tight up under the bottom, at the rear of the disk and they are short. The left one I can turn, the right one is blocked by that double knob that hangs down to adjust the x,y of the stage. You have to be a skinny fingered watchmaker to work them. Maybe tape the two eyepieces together.

It's a ways off though, I need the lens first.

Charles Krebs · Post by **Charles Krebs** » Sun Nov 27, 2011 6:56 pm

Sounds great, in theory. On my BH2 I have to use both hand to twiddle the 2 centering screws

Piece of tape? Small paper or plastic tube/cylinder? If you don't have a phase telescope it is a nice technique to know. Outside of aligning phase rings, there are a variety of other occasions where you might want to observe the rear focal plane better than is possible with the naked eye.

NikonUser · Post by **NikonUser** » Sun Nov 27, 2011 8:14 pm

Charles Krebs wrote:
...... and carefully hold it up, top to top (eye-lens to eye-lens) to the other eyepiece that is still inserted. Look into the back of the eyepiece you are holding and you can get a very good look at the objective rear aperture. Easy to align phase rings that way.
Charles, your last comment about tape /tube is out of context.
Your original technique, quoted above, was to hold and continue holding the eyepiece.
I think you are moving the goal posts

Charles Krebs · Post by **Charles Krebs** » Sun Nov 27, 2011 11:50 pm

Charles, your last comment about tape /tube is out of context.
Your original technique, quoted above, was to hold and continue holding the eyepiece.
I think you are moving the goal posts

Huh!?

Just wanted to give a tip on how it is possible to view the rear aperture simply and quickly when a phase telescope is not at hand.

How it is implemented is up to the user.

Mitch640 · Post by **Mitch640** » Mon Nov 28, 2011 7:51 pm

Here's a nice video on Adjusting Phase, with and without a telescope. He shows several easy tricks.

http://www.youtube.com/watch?v=vPxtt8Bjaus