Just arrived in the mail from Russia

[Crater Eddie]

Oh dear, what have we here?



CE

[mrsonchus]

Looks intriguing Ed!
I must know what's in there! What's in the bage Ed? Ed, what's in the bag.............

[75RR]

A very very little brother for Boris?

[MicroBob]

It doesn't really matter any more since the content was destroyed when it was hit with the post office stamp. Now proove that I'm wrong, Eddie!

Bob

[Crater Eddie]

I was a little surprised that it came in a bag, this seller usually packs things very well. Actually, he did wrap it in several layers of bubble wrap, so it arrived in perfect condition, despite the efforts of the brutal postage handlers, both Russian and American.
For years I have been looking for a 5 position objective turret for Boris. I finally found one, it arrived today. Of course it doesn't fit.
This is for a POLAM, which I knew. I thought it would fit Boris, my L-2-2 or at least Natalia, my POLAM hybrid. However, the mounting fitting on each is just different enough that this won't fit.
I need yet another piece.
So the search continues.
CE

[75RR]

For years I have been looking for a 5 position objective turret

Know what you mean. My first microscope had a 3 objective nosepiece, my second had 4.

When I upgraded to a Standard 18 I was really pleased to be able to get a 5 objective one. Now have two!

However, I have been unable to sleep well since I saw a 7 objective nosepiece on ebay ;)


I suppose it is easy to assume that a nosepiece can withstand a bit of abuse as they feel heavy and solid - they are however quite delicate,

as accurate parcentering and to a certain extent parfocality depend on the area where the objective rests on being unblemished.

I have heard that even overenthusiastic cleaning can put an objective off.


On a slightly different topic, it is amazing how 'easily' the colour shifts in digital photography. I am referring of course to your nice beech table.

Were both images taken at the same time?

[Crater Eddie]

Yes, both photos were taken just moments apart and on the same area of the table, you can see the same knot in the wood in both photos. I guess the colour balance was affected by the variation in the different surfaces of the turret... white v/s chrome. Funny, I didn't even notice that until you mentioned it.
The good news is that I kept the mount that originally came on the L-213 POLAM stand, and after I finally found it safely stored away in a box in the closet, the 5 space turret fits it perfectly. Of course the bad news is that none of my viewing heads fit it so I'm still out of luck. I guess I'll eventually have to get the intermediate section and the proper POLAM viewing head to make everything work.
CE

[Crater Eddie]

I have been unable to sleep well since I saw a 7 objective nosepiece on ebay

7 position turret?! That sure would be great, assuming that it doesn't come with it's own set of hidden issues. 4 is so limiting, though one does get accustomed to it eventually. The BH-2 has a 5 position turret, it makes it awkward switching back and forth between the two scopes.
Upon further "reflection" , I think the main difference in the previous photos was flash v/s no flash.
Regarding parcentricity, the LOMO POLAM 5 position turret has centering screws so each objective can be centered with the rest of the optical train, see photo below. If I ever get it all put together I'll have to find the special wrench that fits the square posts.
I didn't really intend to fit this stand back out to it's original configuration as a POLAM, but it looks like I am headed in that direction. It might take a few more years and lots of $$$ of course.



By the way, I have switched to using Postimage to host my images, it is simple to use and seems to work well. I trust my images are showing ok with no issues?

CE

[75RR]

By the way, I have switched to using Postimage to host my images, it is simple to use and seems to work well. I trust my images are showing ok with no issues?

Now that you are using flash ... no issues :)

Regarding parcentricity, the LOMO POLAM 5 position turret has centering screws so each objective can be centered with the rest of the optical train, see photo below.

That is a pretty neat idea!

[einman]

The Leitz Diaplan has a 5 position turret and the Aristoplan has a 6 position turret. Leica currently offers 7 position turrets. In fact one of teh reasons holding me back from purchasing an Aristoplan is teh nose turret is not compatible with my Diaplans and so all the work I did assembling several 5 position turrets complete with objectives would have been in vain!

[apochronaut]

It all depends on how much one values or uses specific odd objectives. Having used a 6 objective nosepiece for about 4 years now, I can't say there have been too many times that I miss either the 2X or 63X when the other is installed in the extra hole. I guess it is nice to have a full complement at your fingertips. If I need a 2, it is usually for a specific large area view and a 63 nor a 100 are likely needed anyway and the other way around, when I have need for the 63, it then also usually involves the 100 and some very small things. A good flat field 4X can perform the scanning duty admirably, so the 2 is kind of superfluous in that context.

I also use 5 place and 4 place. I don't really find a 5 place much of a handicap when compared to a 6 but I do with a 4 place. I use a 20X a lot , so I tend to relinquish the 4X , when using a 4 place.

Jena offered 7 place nosepieces for many years, I think for the Laboval. I had one here for a while. I certainly never used every objective in the nosepiece during a session.

Things have changed now though, and it isn't uncommon for a microscope to be fitted with two objectives of the same magnification that perform different tasks and the 1X or 1.5X objective has emerged as well, so I guess 7s are becoming more necessary.