Epi DIC on the Balplan

[Scarodactyl]

Alrighty, I finally took some photo stacks on my epi DIC balplan. I picked this unit up while on my epi DIC quest, but it was in kind of rough condition and presented a little poorly as a result, and I ended up setting it aside and not getting back to it until recently. Once I got it taken apart, the old grease all removed and some fresh oil so I could slide the prism in and out (to tune the color) as well as moving it up and down (to match it to each objective) it yields much more impressive results. I still need to replace the delaminated polarizers but otherwise it seems to be working pretty well.
So here are a few photos of a hematite crystal surface (plus a diatom test slide at 20x) taken with the various objectives. I have increased the contrast and cropped a bit to remove some corner vignetting (my camera adapter is still not perfect and leans a little bit sometimes--something to improve).
Click for a slightly larger size, these are still downsized to 1500 width for web usage but honestly there isn't a ton more resolution anyway.
5x:

10x:

20x:


40x:




Overall I think it's a really nice system. You're very limited in which objectives are going to work on it though--I'm honestly not sure if there are others available than the 5x, 10x, 20x and 40x I have. Other systems' objectives will never work perfectly I suspect, and even the microzoom ones don't seem to be fully compatible. I do wonder if it could be successfully ported over to another system (with no offense meant to Microb's previous project, the effect seen on the bh2 adaptation was a bit weak vs what the system can produce).

[BramHuntingNematodes]

Yes I got a microzoom objective the other day, the 2.25x, and it doesn't seem to work at all on the flat field dynazoom, even after.removing the head to get the proper working distance.

[apochronaut]

Since the objectives are semi-objectives and require the 5X negative rear doublet to complete both their magnification and flatten their field I would be surprised if any objectives other than certain select B & L flat field and planapochromats will work. The only BF/DF epi objectives catalogued were the 2.5X , 5X, 10X , 20X , 40X and 100X, which are in fact .5X, 1X, 2X, 4X , 8X and 20X.
There was also a flat field MET microscope with 24mm objective threads. It used a 5X negative common doublet as well , which appears to be somewhat compatible with those used in the Balplan. Here is why somewhat. I have two 5 X .10 ( therefore 1X) flat field achromats without an annular illumination collar and an 80X .90 ( therefore 16X) flat field fluorite with an annular illumination collar. I bought a 24mm to R.M.S. adapter so I can use them on a Balplan and oddly, while the 5X will focus, it displays all kinds of off axis distortion but the 80X works perfectly, with an edge to edge flat and well corrected field. Both objectives are marked 211/0, came from the same source and are marked Met Lab in the same script.
Here is an 80X flat field achromat that appears to be a similar physical design to the two 5X I have but does have the illumination window.

https://www.ebay.com/itm/BAUSCH-LOMB-80 ... ect=mobile.

and another that although it has the illumination annulus is marked 211/0 and has the 24mm thread, looks similarly constructed to the R.M.S. BF/DF objectives.

https://www.ebay.com/itm/Bausch-Lomb-DF ... ect=mobile