Leica DM IL and PHACO 2 And 160/0.17

[microb]

Hi,

I've been mostly focused on metallurgical and metrology microscopes, so I have not used inverted. So with an inverted microscope like the Leica/Leitz DM IL (pre-LED model), what PHACO 2 objective is valid to use? The only ones I'm finding are not 160/- but 160/.017's and that would mean a cover glass of .17mm. How does a cover glass factor into an inverted set up.

And does anyone know what microscope models go with a Leitz Wetzlar 170/0.17 PL APO 16/0.40? I'm assuming a 160 set up would not work.

Thanks,
Ted

[75RR]

And does anyone know what microscope models go with a Leitz Wetzlar 170/0.17 PL APO 16/0.40? I'm assuming a 160 set up would not work.

See page 14: http://www.microscopy-uk.org.uk/mag/img ... es7rev.pdf

[microb]

Modeled the PHACO2 S55 annulus. Will try printing out a PH1 based on some data. I have a S55 PH2 here to check things against.

Will then try to test the microscope with a PHACO1 objective.

[microb]

So I'm remeasuring again.

Thanks,
Ted

[PeteM]

Hi, I've been mostly focused on metallurgical and metrology microscopes, so I have not used inverted. So with an inverted microscope like the Leica/Leitz DM IL (pre-LED model), what PHACO 2 objective is valid to use? The only ones I'm finding are not 160/- but 160/.017's and that would mean a cover glass of .17mm. How does a cover glass factor into an inverted set up. . . .
Thanks, Ted

Ted, With an inverted scope you're typically viewing THROUGH something like a Petri dish. An objective spec'd for .17mm cover slips could be used with the slide upside down. Most objectives for inverted scopes are spec'd at something like 1, 1.2, 1.4mm etc. Some will have a correction collar that goes from something like 0 (no cover) to 2mm. At low magnifications (say, 10x) this won't matter so much. Once you get up to and beyond 20x, you want the right corrections.

As far as phase condensers and annuli go, inverted scopes often have a long working distance condenser of somewhat lower numerical aperture than the 1.25+ you might be used to in an upright compound scope.

[microb]

Hi Pete,

So what you are stating about the thickness of a petri dish is what led me to posting my question. The .17mm thickness is not applicable to an inverted. So what do people use on a Leica DM IL? It has PH2 and PH3 (or at least people are selling the annulus slide loaded with such), but all those higher objectives are 160/.17 not 160/-.

So are people selling DM IL's with anything other than PH1 and DF selling an invalid configuration?

Thanks,
Ted

[microb]

Fixed the mask dimensions for PH2. Inner diameter is 5mm. Outer is 5 + .42 + .42. Web fingers are .6mm wide.

[microb]

So for PH1, 3mm inner, 3_.38_.38 outer. Fingers .53.

[microb]

So does this adjust to vary the thickness?

https://www.ebay.com/itm/Leitz-40X-EF-P ... %7Ciid%3A1

[PeteM]

If it says "-" the objective is relatively insensitive to how much glass is between the objective and specimen. Usually lower power objectives.

If it says "0.17" then it expects not much more than a thin glass cover slip (.17mm thick) between the objective and speciment.

Here's an example of a Leitz objective that adjusts to different thicknesses of glass (Petri dish bottom, slide thickness, etc.) between the objective and specimen in an inverted scope: https://www.ebay.com/itm/Leitz-Microsco ... SwjXBbv7Bb

Here's a LWD (Long Working Distance) type that would be suitable for an inverted scope: https://www.ebay.com/itm/Leitz-20-0-32- ... Sw8~1eV~nk

[75RR]

There are petri dishes with .17 bottoms: https://www.tedpella.com/section_html/p ... dishes.htm

Some microscopists make their own: http://www.microscopy-uk.org.uk/mag/ind ... vert2.html

[microb]

Thanks.

160/0.6 to 1.6

[Hobbyst46]

There are petri dishes with .17 bottoms: https://www.tedpella.com/section_html/p ... dishes.htm

Some microscopists make their own: http://www.microscopy-uk.org.uk/mag/ind ... vert2.html

From personal knowledge - commercial, rather than DIY-ed, dishes are recommended. They can be rinsed with water, dilute caustic, ethanol, and recycled. Avoid strong organic solvents like acetone or other ketones.