experience with a plan 1x compound microscope objective ?

Everything relating to microscopy hardware: Objectives, eyepieces, lamps and more.
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Scarodactyl
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Re: experience with a plan 1x compound microscope objective ?

#31 Post by Scarodactyl » Mon Jun 20, 2022 5:43 pm

Milou wrote:
Mon Jun 20, 2022 5:25 pm
I was speaking about your comments on using two 4x plan infinite objectives, in this file:
https://www.photomacrography.net/forum/ ... 25&t=40640
The person runnjng that test was Macro Cosmos (Daniel Han). Not that I'd mind being confused for him, it's high praise.

Dmgreene
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Joined: Mon Jun 20, 2022 5:11 pm

Re: experience with a plan 1x compound microscope objective ?

#32 Post by Dmgreene » Mon Jun 20, 2022 5:48 pm

First Let me start by introducing myself, my name is Michael Greene and I live in Alabama in the United States. my dad and I have been selling Olympus Microscopes mainly to the Universities and Hospital markets. My wife has been the gardener in the family, but now in my retirement I have become interested in the science involved in farming at a amature level with higher level tools I now have available to grow plants and vegatables while learning the basics of Plant Pathology with my stereo microscope capable of darkfield illuimation, and more than likely many other things to learn maybe soil science and such.

Milou
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Joined: Mon Nov 22, 2021 1:31 pm

Re: experience with a plan 1x compound microscope objective ?

#33 Post by Milou » Tue Jun 21, 2022 12:07 pm

Scarodactyl wrote:
Mon Jun 20, 2022 5:43 pm
Milou wrote:
Mon Jun 20, 2022 5:25 pm
I was speaking about your comments on using two 4x plan infinite objectives, in this file:
https://www.photomacrography.net/forum/ ... 25&t=40640
The person runnjng that test was Macro Cosmos (Daniel Han). Not that I'd mind being confused for him, it's high praise.
Thank you scarodactyl for correction about this file
I was probably distracted :-)

Chas
Posts: 183
Joined: Tue Jan 19, 2021 3:11 pm

Re: experience with a plan 1x compound microscope objective ?

#34 Post by Chas » Wed Jun 22, 2022 8:15 pm

A couple of stacks using the cheapo x1 and a 60mm efs macro at ~1:1

...No special lighting ..just what came in through the window.

x1 lens:
x1 stack wing.jpg
x1 stack wing.jpg (104.28 KiB) Viewed 226 times


Canon 60mm efs (at f8):
60mm wing.jpg
60mm wing.jpg (145.03 KiB) Viewed 226 times

viktor j nilsson
Posts: 637
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Location: Lund, Sweden

Re: experience with a plan 1x compound microscope objective ?

#35 Post by viktor j nilsson » Wed Jun 22, 2022 9:11 pm

Thanks for sharing, the 1x looks horrible.

photomicro
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Location: UK

Re: experience with a plan 1x compound microscope objective ?

#36 Post by photomicro » Thu Jun 23, 2022 6:54 am

viktor j nilsson wrote:
Wed Jun 22, 2022 9:11 pm
Thanks for sharing, the 1x looks horrible.
But, to be fair...isn't the microscope objective corrected for transmitted light, and the macro for reflected, which is what this subject is ?

viktor j nilsson
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Location: Lund, Sweden

Re: experience with a plan 1x compound microscope objective ?

#37 Post by viktor j nilsson » Thu Jun 23, 2022 8:12 am

photomicro wrote:
Thu Jun 23, 2022 6:54 am
viktor j nilsson wrote:
Wed Jun 22, 2022 9:11 pm
Thanks for sharing, the 1x looks horrible.
But, to be fair...isn't the microscope objective corrected for transmitted light, and the macro for reflected, which is what this subject is ?
Can't see how that would matter in this case. At such low NA, presence or absence of cover slip doesn't matter. Lots of low magnification (4x-10x) microscope objectives designed for transmitted illumination produce excellent to stellar results when used as reflected light macro objectives.

Scarodactyl
Posts: 2011
Joined: Sat Mar 03, 2018 9:09 pm

Re: experience with a plan 1x compound microscope objective ?

#38 Post by Scarodactyl » Thu Jun 23, 2022 8:15 am

photomicro wrote:
Thu Jun 23, 2022 6:54 am
viktor j nilsson wrote:
Wed Jun 22, 2022 9:11 pm
Thanks for sharing, the 1x looks horrible.
But, to be fair...isn't the microscope objective corrected for transmitted light, and the macro for reflected, which is what this subject is ?
No, that isn't a factor here. Objectives aren't corrected for transmitted or reflected light per se (though working distance and barrel design may encourage or discourage reflected light). They may be corrected for having a cover slip or not having a cover slip, but at low numerical apertures objectives do not care at all either way.
Edit: beaten to the punch while composing.

Milou
Posts: 66
Joined: Mon Nov 22, 2021 1:31 pm

Re: experience with a plan 1x compound microscope objective ?

#39 Post by Milou » Thu Jun 23, 2022 8:31 am

Thank you Chas for this interesting test

I will have next week an Olympus 1x Splan Fl 1 0.04/160 to test it........

I'll also try to compare with my macro lens 60mm (Olympus on a M4/3 camera) at 1:1 ratio

Chas
Posts: 183
Joined: Tue Jan 19, 2021 3:11 pm

Re: experience with a plan 1x compound microscope objective ?

#40 Post by Chas » Thu Jun 23, 2022 10:40 am

These two are not strictly comparable as I had to 'answer the illuminator' (mobile phone) in between ( the position and width of view are not well matched either).
I tried to focus on the centre with the x1 lens.

Just single unstacked photographs:

x1:
x1 single shot section.jpg
x1 single shot section.jpg (92.21 KiB) Viewed 179 times
35mm efs macro:
35mm efs section 9 800.jpg
35mm efs section 9 800.jpg (168.15 KiB) Viewed 179 times
The slide was resting on a diffusing plastic which might be the worst possible lighting for the x1

A couple of crops out of the middle:
x1:
x1 crop1 7.jpg
x1 crop1 7.jpg (56.17 KiB) Viewed 152 times


35mm efs:
35 efs 009 crop1.jpg
35 efs 009 crop1.jpg (145.15 KiB) Viewed 152 times

Chas
Posts: 183
Joined: Tue Jan 19, 2021 3:11 pm

Re: experience with a plan 1x compound microscope objective ?

#41 Post by Chas » Fri Jun 24, 2022 8:44 pm

I am not sure if this is useful, but I have just tried a single element 75mm microscope objective positioned roughly 160mm from the camera sensor, if my amateur maths are correct this should have given 1:1
'horseshoe style' stands seem to have an RMS-threaded mounting at the bottom of their draw tubes and this is where it is suggested that long focal length objectives are placed.. I guess so that the draw tube can be pulled out to get sufficient working distance.

On the draw tube of a Cooke Troughton Simms and direct projecting into the DSLR (so further away than the normal 160mm or should it be, in this case, 150mm? ):
Beck 75mm lens on bottom of CTS draw tube.jpg
Beck 75mm lens on bottom of CTS draw tube.jpg (144.89 KiB) Viewed 142 times
I was quite surprised that it wasnt so terrible ... maybe if you can achieve equal spacings either side of the objective lens.. a simpler lens might suffice (???)

Milou
Posts: 66
Joined: Mon Nov 22, 2021 1:31 pm

Re: experience with a plan 1x compound microscope objective ?

#42 Post by Milou » Sat Jun 25, 2022 11:10 am

Milou wrote:
Thu Jun 23, 2022 8:31 am

I will have next week an Olympus 1x Splan Fl 1 0.04/160 to test it........

I'll also try to compare with my macro lens 60mm (Olympus on a M4/3 camera) at 1:1 ratio
In fact I get it today

I have tried it on my Leitz setup with tubes between a M4/3 camera and objectives (about 160 mm between objective and camera sensor) instead of a Leitz head
But perhaps this objective need correction through special eyepieces......
and impossible to focus correctly on the item under the cover slide!

It has an extremely small WD (more or less 1 mm) ........

Chas
Posts: 183
Joined: Tue Jan 19, 2021 3:11 pm

Re: experience with a plan 1x compound microscope objective ?

#43 Post by Chas » Sat Jun 25, 2022 2:38 pm

Milou,
about 160 mm between objective and camera sensor
The 160mm written on an objective is a bit misleading, for direct projection ..it is the "mechanical tube length" ; a measurement from the bottom of the RMS thread to the top of the tube where the eyepiece sits.

Unfortunately the actual focus point is someway down inside the eyepiece so the distance from the RMS thread to your sensor needs to be less than 160mm.
I understand that this is generally around 10mm less (but, for example, Cooke Troughton Simms it was 20mm less)

It is often said that low magnification objectives are not very sensitive to changes in tube length.... but the field of view /working distance on my X1 is super sensitive !!

There is a discussion here about Leitz tube lengths and eyepiece types:
viewtopic.php?t=7229

Milou
Posts: 66
Joined: Mon Nov 22, 2021 1:31 pm

Re: experience with a plan 1x compound microscope objective ?

#44 Post by Milou » Sat Jun 25, 2022 3:14 pm

Thank's for comments Chas,

The distance between RMS thread bottom and camera sensor is 16.2 cm in my setup !

With other objectives, including a 2.5x Zeiss plan, this distance, can be changed without losting focus point!

But as you said, it is perhaps different with this Olympus 1x Splan......
Perhaps is it, contrary to the other ones, sensitive to tube length....

I'll try to modify tube length, in order to find (I hope so!) the focus point for this 1x objective....

This Olympus 1x Splan Fl 1 0.04/160 is very large and heavy, comparing to the other objectives:
-43 mm long (without RMS thread ;
-27 mm for front objective diameter and almost 25 mm for front lens!

Chas
Posts: 183
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Re: experience with a plan 1x compound microscope objective ?

#45 Post by Chas » Sat Jun 25, 2022 8:46 pm

and almost 25 mm for front lens!
...The front lens element of this Chinese x1 is 5mm at most ! :(

BramHuntingNematodes
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Location: Georgia, USA

Re: experience with a plan 1x compound microscope objective ?

#46 Post by BramHuntingNematodes » Sun Jun 26, 2022 12:01 am

There's at least one cool trick you can do with a 1x:


Image

This is the Zeiss Plan 1x .04. I cheated a little bit as this image is about twice as big as spec thanks to some adjustable drawtube fiddling also I can never be totally sure how much compensation Zeiss lenses need this is using the B&L low ultraplane but might look better with the medium or even a real Zeiss eyepiece.
1942 Bausch and Lomb Series T Dynoptic, Custom Illumination

Milou
Posts: 66
Joined: Mon Nov 22, 2021 1:31 pm

Re: experience with a plan 1x compound microscope objective ?

#47 Post by Milou » Sun Jun 26, 2022 1:26 pm

I've modified tube length and reduced it to 15 cm.
Therefore I could find the focus point for this Olympus 1x objective

Just a picture to show how large is the field with this Olympus 1x (cover slide here is 20mm diameter!)....

Lighting is not good as I had to take off the condenser (in order to avoid just a central circle illuminated!) .......
I'll have to change the original lamp inside the Leitz stand up with a stronger LED
The WD is very small : 2.2 mm and that's impossible to add an episcopic lighting. Therefore the spines structure of lamina dorsalis an ventralis (dark pieces, above left) cannot be discerned!

But not enough time to adapt another lighting to my setup, as it is not strong enough here

This Olympus 1x objective, even with a good optical quality, is in fact not adapted for my use: field too large and WD too small :-)

I will also make pictures of the same slide, with a 60mm macro on a M4/3 (and eventually adding a Raynox lens)

P1020015.resized.JPG
P1020015.resized.JPG (101.11 KiB) Viewed 36 times
Olympus 1x plan, Zygaena purpuralis genitalia

If anybody is interested by this objective, PM me
Last edited by Milou on Sun Jun 26, 2022 2:31 pm, edited 2 times in total.

Hobbyst46
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Re: experience with a plan 1x compound microscope objective ?

#48 Post by Hobbyst46 » Sun Jun 26, 2022 1:34 pm

Milou wrote:
Sun Jun 26, 2022 1:26 pm
Just a picture to show how large is the field with this Olympus 1x (cover slide here is 20mm diameter!)....
Naturally, the field of view with a 10X objective is about 2mm (1.8mm on an fn 18 microscope) so a 1X objective is expected to cover ~20mm.
Zeiss Standard GFL+Canon EOS-M10, Olympus VMZ stereo

viktor j nilsson
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Location: Lund, Sweden

Re: experience with a plan 1x compound microscope objective ?

#49 Post by viktor j nilsson » Sun Jun 26, 2022 2:57 pm

Somewhat counterintuitively, low NA low magnification objectives have a greater depth of field at the subject plane, but a shallower depth of focus at the image plane. High-NA objectives are the reverse, with razor thin depth of field at the subject, and a very great depth of focus at the image side.

In terms of optical aberrations, low-NA objectives are very tolerant to tube length errors, whereas high-NA objectives are highly sensitive to deviations in tube length.

So in short: with low mag/low NA objectives, small changes in tube length have a dramatic effect on working distance and focus at the sensor, but little effect on image quality. With high mag/high NA objectives, small changes in tube length have little effect on focus, but dramatic effects on image quality.

This is also why it's important to use a relatively low mag (10x) objective when adjusting parfocality.

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