I've been working on the stylus microscope and it's almost there. With help from my friend Dave Kloss (son of the audio legend Henry Kloss), the X-Y stage is now reworked to allow both headshell-mounted carts and removed stylii to be examined and I have a lighting system that seems to work well.
The microscope I started with was made to view slides and had no vertical room to put a stylus or cartridge into the viewing area. The stage and lighting mods have fixed most problems. The one snag is optics. I bought a 20X objective lens to work with the 10X eyepieces to give the desired 200x magnification. However, this 20x objective needs to be within 1-2mm of the object to focus (the "Working Distance") so the lens itself blocks a lot of the light coming in from beside and above the stylus. The light needs to reflect off and up any flats on the stylus tips caused by wear, creating two bright spots. Having the objective down so close is also a bit risky for the stylus. I have someone else spot me to make sure I do not go too far down and cause an expensive crunch.
It works quite well with 100x magnification because the Working Distance of the 10x objective is about 8mm above the stylus tip and that's enough room to let light in. I'd like to get it going at 200x either by using the 10x objective with 20x eyepieces (this is the best bet) or by finding a shorter 20x objective (not sure if any 20x has enough Working Distance).
Does anyone have any or all of the following that I could borrow at Clinton for the day:
- 5x and/or 20x eyepieces to go into the standard 23mm barrel diameter. We'd use the 5X to set up the view and the 20X to see details.
- A short 20x objective in standard DIN thread (20.1mm diameter, 36 TPI) if it has a Working Distance of at least 6mm or so.
Ideally, I'll be able to get some used stuff by Saturday but that may not happen. We'll be fine with 100x but I'm hoping to get the 200x version working by Saturday. If you know of a place that sells or rents microscopes and parts anywhere near Boston, please let me know.
Please PM me if you can help out. Thanks. --Dan
PS - If you want to learn more about this stuff,
read it here.