Kyowa microscope SDZ-P, can I add a Barlow lens?

[jpmort]

I have just got an old Kyowa stereo scope, with 10x eyepiece. I think it's an SDZ-P but maybe an older type. It has two zoom levels, which is great. But I need greater working distance under the objective lens, and I would like to reduce the magnification for watch work.  

The objective shroud does not have an internal thread for a Barlow lens, despite the fact that the online instructions seem to indicate one can be fitted. 

Has anyone here got one of these, and have you fitted a 0.5 Barlow lens to it?

Thanks,

[jpmort]

I have removed the lens shroud and I have more distance now. But the question I still have is that I would like to reduce the overall magnification. Would a Barlow lens work best. Or, woudl a 5x eyepiece, rather than the 10x that I am using now, also do the job?

[mikepilk]

Changing the eyepieces does not effect the working distance - it would just make things look smaller 

[HectorLooi]

Does the lens shroud have any threads in front?

[jpmort]

15 minutes ago, mikepilk said:

Changing the eyepieces does not effect the working distance - it would just make things look smaller 

yes, I what to decrease the magnification, but I want to increase the field of view to get the whole watch in the view. Would putting in the 5x eyepiece increase the field of view in a similar way to a Barlow lens? 

Thanks.

I hav removed the shroud. The knurled part does have a thread 64mm wide, the black part is smooth. I have removed the whole shroud in the picture here. 

I wonder if I can get a tube extension that I can screw into the knurled part of the shroud, but extend past the objective lens to put the Barlow on?

[jpmort]

4 hours ago, HectorLooi said:

Does the lens shroud have any threads in front?

I posted a pic of the shroud removed, and a description of what might be possible. The knurled part detaches from the black part of the shroud, and the knurled part is 48mm, and has a thread. I could put on a lens there, but the objective lenses protrude.

[HectorLooi]

The barlow lens is supposed to fit to the front of the shroud. Are there any threads there?

[mikepilk]

When I replace my 10x with 20x eyepieces the FOV decreases whilst the working depth stays the same.

So the 5x eyepieces should increase the FOV, but I don't know if it would be limited by the main lens.

[jpmort]

5 minutes ago, mikepilk said:

When I replace my 10x with 20x eyepieces the FOV decreases whilst the working depth stays the same.

So the 5x eyepieces should increase the FOV, but I don't know if it would be limited by the main lens.

Thanks, thats helpful. What I actually want to do is to use the Barlow first. If that does not work, then go down the 5x route.

29 minutes ago, HectorLooi said:

The barlow lens is supposed to fit to the front of the shroud. Are there any threads there?

On the silver knurled shroud, yes there is a thread of 48mm, but the objective lens protrudes.
The black part of the shroud does not have any thread.

 

[HectorLooi]

30 minutes ago, jpmort said:

On the silver knurled shroud, yes there is a thread of 48mm, but the objective lens protrudes.
The black part of the shroud does not have any thread.

Maybe you could get a 48mm lens extension kit and add enough rings to clear the objective lenses.

M42 M48 Extension Tube Kits 3/5/7/10/12/15/20/30/40/50mm For Astronomical Telescope Photography T Extending Ring
https://a.aliexpress.com/_mtt6UfN

 

[jpmort]

25 minutes ago, HectorLooi said:

Maybe you could get a 48mm lens extension kit and add enough rings to clear the objective lenses.

M42 M48 Extension Tube Kits 3/5/7/10/12/15/20/30/40/50mm For Astronomical Telescope Photography T Extending Ring
https://a.aliexpress.com/_mtt6UfN

 

Ah, yes, that makes sense. It's M48 so it will fit. I might give that a try. Thanks. I will get the lens first, so I know the length of extension I need.

[jpmort]

If I buy a longer pillar for the microscope, as I might need it with the Barlow lens, I measures my existing one with a set of callipers. The width turns out to be 24.7mm. I understand that almost all microscope pillars are 25mm. So I am not sure whats going on. Could someone please measure their pillar with something accurate, like callipers, and let me know the exact diameter? Weird.

Thanks.

[tomh207]

1 hour ago, jpmort said:

If I buy a longer pillar for the microscope, as I might need it with the Barlow lens, I measures my existing one with a set of callipers. The width turns out to be 24.7mm. I understand that almost all microscope pillars are 25mm. So I am not sure whats going on. Could someone please measure their pillar with something accurate, like callipers, and let me know the exact diameter? Weird.

Thanks.

I expect that would be well in tolerance for the application as nominal 25mm

 

Tom

[HectorLooi]

11 hours ago, jpmort said:

The width turns out to be 24.7mm.

Out of curiosity, I measured mine. It turned out to be 24.94mm.

I think the diameter of the hole in the microscope arm is more important. If the hole is smaller than 25mm and you get a new post that is bigger than the mounting hole.... that would be a problem.

[jpmort]

On 3/16/2025 at 1:44 PM, tomh207 said:

I expect that would be well in tolerance for the application as nominal 25mm

 

Tom

Thanks youre probably right, I might just be getting too detailed!

14 hours ago, HectorLooi said:

Out of curiosity, I measured mine. It turned out to be 24.94mm.

I think the diameter of the hole in the microscope arm is more important. If the hole is smaller than 25mm and you get a new post that is bigger than the mounting hole.... that would be a problem.

Thanks for checking. Youre probably right, I might just be getting too detailed!

Edited March 17 by jpmort