Zeiss IM with hoffman modulation
Posted: Sat Oct 22, 2022 10:32 pm
I picked this up a few months back at a university surplus sale but business has been busy and I only managed to track down the proper power supply and replacement bulb. It's a real big Zeiss inverted scope with a hoffman condenser and, oddly, Nikon hoffman objectives.
For the most part it seems to be in good shape, though there is some delam in the head and eyepieces and the condenser rack and centering screws are stuck. (I really need some tips on the screws and rack in particular, not sure if I should try oil or?)
Unfortunately I really don't have a strong idea of how to use hoffman modulation, or an inverted scope in general. I'm sure I'll resell it eventually (though I'm not looking forward to moving or packing it up, it's heavy!) but I wanted to at least get a taste of this technique and see how it compares. I am able to get some images which seem fairly similar in effect to Leica's Rotterman contrast or other tuned oblique illumination with a bit DIC flavor to them. It has three hoffman objectives and some phase as well, but I only seem to get good results with two of the hoffman filters (it has three hoffman filters and one open slot).
The condenser pillar has two pencil lines, one higher up marked 'phase' and one lower down labeled 'hoffman' so presumably it once had another condenser.
I'll be honest I really don't have a great idea of how to use this scope but I do like what I'm seeing of Hoffman so far. I assume it will work better when I can get kohler set up.
For the most part it seems to be in good shape, though there is some delam in the head and eyepieces and the condenser rack and centering screws are stuck. (I really need some tips on the screws and rack in particular, not sure if I should try oil or?)
Unfortunately I really don't have a strong idea of how to use hoffman modulation, or an inverted scope in general. I'm sure I'll resell it eventually (though I'm not looking forward to moving or packing it up, it's heavy!) but I wanted to at least get a taste of this technique and see how it compares. I am able to get some images which seem fairly similar in effect to Leica's Rotterman contrast or other tuned oblique illumination with a bit DIC flavor to them. It has three hoffman objectives and some phase as well, but I only seem to get good results with two of the hoffman filters (it has three hoffman filters and one open slot).
The condenser pillar has two pencil lines, one higher up marked 'phase' and one lower down labeled 'hoffman' so presumably it once had another condenser.
I'll be honest I really don't have a great idea of how to use this scope but I do like what I'm seeing of Hoffman so far. I assume it will work better when I can get kohler set up.