MicrobeHunter.com Microscopy Forum

I have a Nikon TMD Diaphot with an ELWD 0.3 phase contrast condenser. From a physics/optics standpoint, is there any reason a higher NA condenser wouldn't work with this scope? I don't use petri dishes so I don't need the working distance. I'm wondering if there is a Nikon condenser with higher NA that would fit in my scope's dovetail condenser holder. I'd like to take better advantaage of my higher NA objectives, and also be able to shoot darkfield with more than the 10X I'm currently limited to. These are my objectives:

Nikon 10/0.25 Plan Phase Contrast
Zeiss 16/0.40 NeoFluor PH2
Nikon 20/0.75 Plan APO
Nikon 40/0.65 Plan Phase Contrast
Nikon 40/1.30 Fluor Oil Immersion
Nikon 40/1.0 Plan APO Oil Immersion
Nikon 100/1.30 Fluor Oil Immersion

I wouldn't care about losing the Phase Contrast capability, I rarely use it, and if I wanted to I could swap back in the current condenser as necessary. I do have the Nikon fluoriescence setup attached, it would be nice to be able to use that with any replacement condenser. Thanks.

There is a LWD condenser for that model having an na of 0.5 you may want to look for on e-bay.

I would potentially worry about losing some light from the light source being much further above the condenser, but other than that, I cant see any reason you would encounter issues

I would think even if factory solution does not exist (which is unlikely), it would not be difficult to adapt a high NA condenser and LED light source onto Diaphot. Does that condenser holder go low enough?

With the hanging drop method (with upside-down cover slip - slide), you can have an 0.17mm spec’ed objective (facing up and) oiled to cover slip and condenser (facing down and) oiled onto slide bottom.

einman wrote: ↑

Sun Feb 04, 2024 12:11 am

There is a LWD condenser for that model having an na of 0.5 you may want to look for on e-bay.

Thanks. Yes I'm aware of that condenser, but I'm hoping for even higher N.A.

zzffnn wrote: ↑

Sun Feb 04, 2024 5:04 am

I would think even if factory solution does not exist (which is unlikely), it would not be difficult to adapt a high NA condenser and LED light source onto Diaphot. Does that condenser holder go low enough?

With the hanging drop method (with upside-down cover slip - slide), you can have an 0.17mm spec’ed objective (facing up and) oiled to cover slip and condenser (facing down and) oiled onto slide bottom.

Thanks. I'm using a 100W halogen light source on the scope. I'm not familiar with the hanging drop method, I'll search for details. There is a limit on how low my condenser can be lowered -- I'm not sure how I would determine whether it can go low enough. Not sure if I could form some type of extension to the existing dovetail rail to allow it to move even further down. The stage can be raised, however I imagint I would only be able to raise that as far as the eyepiece block can move upward, otherwise I would no longer be able to reach focus? This is part of why I'm asking for advice -- I'd hate to purchase something that can't be used.

Topcode wrote: ↑

Sun Feb 04, 2024 2:27 am

I would potentially worry about losing some light from the light source being much further above the condenser, but other than that, I cant see any reason you would encounter issues

Thanks. I'm currently using a 100W halogen light source, hopefully this would provide enough light in this type of setup.

macnmotion wrote: ↑

Sun Feb 04, 2024 11:54 am

zzffnn wrote: ↑

Sun Feb 04, 2024 5:04 am

I would think even if factory solution does not exist (which is unlikely), it would not be difficult to adapt a high NA condenser and LED light source onto Diaphot. Does that condenser holder go low enough?

With the hanging drop method (with upside-down cover slip - slide), you can have an 0.17mm spec’ed objective (facing up and) oiled to cover slip and condenser (facing down and) oiled onto slide bottom.

Thanks. I'm using a 100W halogen light source on the scope. I'm not familiar with the hanging drop method, I'll search for details. There is a limit on how low my condenser can be lowered -- I'm not sure how I would determine whether it can go low enough. Not sure if I could form some type of extension to the existing dovetail rail to allow it to move even further down. The stage can be raised, however I imagint I would only be able to raise that as far as the eyepiece block can move upward, otherwise I would no longer be able to reach focus? This is part of why I'm asking for advice -- I'd hate to purchase something that can't be used.

Sorry, I don’t have Diaphot to tell for sure, though I know many higher end inverted scopes can lower condenser enough to do hanging drop mount.

You can put a microscope slide on your Diaphot, then lower your current condenser to see if it will touch? Then compare condenser heights and extend on condenser dovetail using Legos / wood / glue, if necessary. It may be also possible to raise the stage using screw washers and longer screws?

zzffnn wrote: ↑

Sun Feb 04, 2024 2:45 pm

macnmotion wrote: ↑

Sun Feb 04, 2024 11:54 am

zzffnn wrote: ↑

Sun Feb 04, 2024 5:04 am

I would think even if factory solution does not exist (which is unlikely), it would not be difficult to adapt a high NA condenser and LED light source onto Diaphot. Does that condenser holder go low enough?

With the hanging drop method (with upside-down cover slip - slide), you can have an 0.17mm spec’ed objective (facing up and) oiled to cover slip and condenser (facing down and) oiled onto slide bottom.

Thanks. I'm using a 100W halogen light source on the scope. I'm not familiar with the hanging drop method, I'll search for details. There is a limit on how low my condenser can be lowered -- I'm not sure how I would determine whether it can go low enough. Not sure if I could form some type of extension to the existing dovetail rail to allow it to move even further down. The stage can be raised, however I imagint I would only be able to raise that as far as the eyepiece block can move upward, otherwise I would no longer be able to reach focus? This is part of why I'm asking for advice -- I'd hate to purchase something that can't be used.

Sorry, I don’t have Diaphot to tell for sure, though I know many higher end inverted scopes can lower condenser enough to do hanging drop mount.

You can put a microscope slide on your Diaphot, then lower your current condenser to see if it will touch? Then compare condenser heights and extend on condenser dovetail using Legos / wood / glue, if necessary. It may be also possible to raise the stage using screw washers and longer screws?

I can do some test measurements. The stage does go up and down and is then locked in place with a set screw, but I'm sure there is an upper limit, as the objective turret can also go up for focus but only a limited amount. so I'll need to determing the highest the stage can be moved and still reach focus, then lower the condenser to see if it can reach the slide.