Leitz SM LUX x100 objective - wrong one?

[martinr]

That didn't take long before I returned with another query!

I bought an oel x100 objective on ebay. I made sure it was a 170 and not a 160, but when I inserted it and focussed with my x40 on a slide, I then swung the x100 round and it was at least half an inch too short. I can't even wind the 'scope close to the slide.

You can see the difference in length of the 2 objectives. I'd really appreciate knowing where I went wrong - I thought the 170mm specification was all I had to watch for - and what I need to do not to repeat the mistake.

Many thanks

Martin

[billbillt]

Hi,

You need to get a certain length of adapter.. I can't recall it, but someone here will surely remember.. This a common problem.. Nothing to worry about...

The Best,
BillT

[Charles]

Leitz offered objectives with two different parfocal distances. The older objectives use a 37 mm parfocal distance (short barrel) while the newer ones were designed for a 45 mm parfocal distance. You can combine the two different objective types on the same nose piece by using special adapters called PLEZY and FLU-PLEZY. The Plezy screws on the back end of the 37 mm objective to make them parfocal with the 45 mm objectives.

[martinr]

Hi,

You need to get a certain length of adapter.. I can't recall it, but someone here will surely remember.. This a common problem.. Nothing to worry about...

The Best,
BillT

Thanks, BillT.

It's not a PLEZY is it?

Leitz PLEZY Microscope Objective adapter

https://rover.ebay.com/rover/0/0/0?mpre ... 1983870208

[zzffnn]

Sorry for the trouble, Martin.

I forgot to mention that difference (see comment from Charles). Yes, you may need a Plezy or a 45mm 170 tube objective, depending on which one is cheaper/more suitable.

[Hobbyst46]

Martin

I had a similar problem with Olympus objectives. On ebay you can find parfocality adapters from China as well as from Europe. Very inexpensive, relative to the original adapters from the microscope manufacturer, and they offer a range of parfocality corrections (like 8mm, 9mm etc). But better verify with the seller BEFORE ordering that the adapter will fit your specific model, do not rely on their specified thread (RMS, etc) alone.

Good luck.

[martinr]

Thanks to everyone. Rather than faff about with an adapter, I've returned the objective to the seller (who doesn't know anything about microscopy), and I've bought a x100 of the correct length from a US eBay microscope-accessory seller with a 100% rating on 4k transactions who knows his product and has guaranteed the mechanical and optical qualities as excellent.

Another rung climbed up the learning curve.

Thanks again all.

Martin

[mrsonchus]

Hi Martin - I have 3 PLEZY adapters in use at the moment - one of which is a 'Flu' type - which I have on a 'shortie' (37mm) Fl objective - they are only about £30 max to buy on e-bay I find. Whenever they come up I usually have a go at buying them - they're really handy.
Here's one on the left-end of this trio of objectives from my Orthoplan's selection.

ws_immersion set (1).jpg (67.44 KiB) Viewed 7743 times

They are really handy - often a high-spec 37mm will appear for virtually a giveaway price - the PLEZY makes it viable!

Here's one on my Orthoplan with it's 'taller companions',

ws_orthoplan delivered (9).jpg (51.74 KiB) Viewed 7743 times

[martinr]

Hi Martin - I have 3 PLEZY adapters in use at the moment - one of which is a 'Flu' type - which I have on a 'shortie' (37mm) Fl objective - they are only about £30 max to buy on e-bay I find. Whenever they come up I usually have a go at buying them - they're really handy.
Here's one on the left-end of this trio of objectives from my Orthoplan's selection.
ws_immersion set (1).jpg

They are really handy - often a high-spec 37mm will appear for virtually a giveaway price - the PLEZY makes it viable!

Here's one on my Orthoplan with it's 'taller companions',
ws_orthoplan delivered (9).jpg

Thank you, John. I can see the attraction of using an adapter in order to be able to fit a higher spec objective. Your photos do come out really well. I read this explanation on eBay.com

"To address the change in parafocal distance, Leitz offered special adapters called PLEZY and FLU-PLEZY that contain a lens to correct for the 8mm extension. The difference between the FLU-PLEZY (Leitz number 519 382) and the PLEZY (Leitz number 519 164) is that the FLU-PLEZY offers better transmission for shorter wavelengths, making it more suitable for fluorescence microscopy. "

So that's an FL x54 oil immersion objective you have. Is the "odd" magnification number a characteristic of the FL type of objective; I have an FL x6.3 objective, and such a strange number intrigued me?

Martin

[mrsonchus]

Hmm, not sure why they choose to make the magnifications they do/have - all I have read re this is that manufacturers tried to roughly double successive objective powers - although in truth I've no idea.

This x54 is a lovely performer, but I found some time ago my prize-objective - a water-immersion x50 of n.a. 1.0 - requiring water between the objective and slide, and nothing between the condenser and slide's bottom. This x50 is an absolutely beautiful objective for superb brightness, resolution and contrast and has made the x54 oel redundant for me.

If anyone would like to buy it, with it's (Flu) PLEZY, I'm interested to sell it - it's languishing in a drawer these days.

I also now have a superb x63 (dry) that goes 'the other side' of the x54 mag - again making it redundant in my rig really.

I also found a nice x40 (37mm shortie) apo with collar for £10 a while back! It now has another PLEZY attached and lives in the nosepiece of my little SM-LUX..

Basically if I see it cheap - I pounce on it! Great fun too - you win some, you lose some - but I've had many more good buys than bad thankfully.

[martinr]

.

This x54 is a lovely performer, but I found some time ago my prize-objective - a water-immersion x50 of n.a. 1.0 - requiring water between the objective and slide, and nothing between the condenser and slide's bottom. This x50 is an absolutely beautiful objective for superb brightness, resolution and contrast and has made the x54 oel redundant for me.

Fascinating; I didn't know there was such a thing as water-immersion objectives. I don't suppose you have any photonicrographs of a specimen taken with your prize possession objective and one taken of the same specimen with the x54 oel (or perhaps one of the same specimen with the x40 dry objective) by way of comparison? I'd love to see the difference it makes. And a water-immersion optic must be far easier to clean, and with much less contact with the lens, than an oil objective

Does it make such a difference that, for example, micron-size items, that you'd otherwise use a x100 to see clearly, can be seen in similar detail (though half the size) as with the x100?

Martin

[mrsonchus]

Fascinating; I didn't know there was such a thing as water-immersion objectives. I don't suppose you have any photonicrographs of a specimen taken with your prize possession objective and one taken of the same specimen with the x54 oel (or perhaps one of the same specimen with the x40 dry objective) by way of comparison? I'd love to see the difference it makes. And a water-immersion optic must be far easier to clean, and with much less contact with the lens, than an oil objective

Does it make such a difference that, for example, micron-size items, that you'd otherwise use a x100 to see clearly, can be seen in similar detail (though half the size) as with the x100?

Martin

Yes Martin old chap, the WI x50 is a dream to use and does as far as I can tell achieve a high n.a. - high resolution (detail) and beautifully bright. I love that objective!
Hmm... I haven't made a direct comparison between the x50 water and the x54 oil, but if I get a chance I will - I'v many different objective comparisons, and I've a recent comparison of the x100 apo 1.32 that I have, the x50 1.0 water and the x63.

Here are a few such images of phloem sieve-plates stained with Toluidine-blue - always a challenge I find to resolve the pore details or shapes - a good subject for testing if the stain is 'contrasty' enough...

These are I think sieve plates from a Sunflower petiole phloem,

objective comparison snip.JPG (95.38 KiB) Viewed 7693 times

The x63 is nominally a 160mm TL objective - but as the optical TL of the 170 and 160mm mechanical TL (the one on an objective's barrel) of Leitz are actually only 2mm apart, as the Leitz memorandum says - there's little if any discernable difference or degradation at the higher n.a. end of objectives...

The images have been made of equal size with software - originally of course they were different due to the different magnifications of the objectives, see below,
The x50 1.0 water objective,

ws_x50 WI.jpg (61.73 KiB) Viewed 7693 times

The x63 dry,

ws_x63.jpg (54.14 KiB) Viewed 7693 times

The x100 1.32 oil,

ws_x100 stacked.jpg (45.73 KiB) Viewed 7693 times

Oh yes, here's an image from my x70 with collar (which I find very underwhelming indeed actually) - not in the top comparison of course, the collar is set to 0.17 here, not that I can really tell any difference.

ws_x70 0_17 collar.jpg (49.06 KiB) Viewed 7693 times

So, not a lot may be learned from this rather poor comparison, but one thing I can say is that there's not a great deal of difference - not enough to base any purchase-preference upon for me. I suspect that a meaningful comparison may require far better equipment, slides and photographic technique than I have - I'm sure there's a significant difference, but I don't think my kit is able to exploit it I'm afraid.

For me - inconclusive at best....

[mrsonchus]

A couple more images,

Here's a nicely resolved pit-field in the cell-wall of a Xylem-ray cell with the 1.32 apo x100 that I really like a lot,

ws_x100 (1).jpg (46.92 KiB) Viewed 7693 times

I really like the detail here of the sectioned Lily pollen grain as seen with the 1.32 apo x100 also, great resolution of the tiny pore through the wall at the top of the grain...

ws_x100-with-na1_4-condense.jpg (78.39 KiB) Viewed 7693 times

Here is the same view with the water x50 with water between slide and objective, and just to see what would happen, oil between the 1.4 n.a. condenser and the slide-bottom - to me it looks easily as well resolved as the x100 oil...

ws_x50-W-obj-with-oiled-1_4.jpg (107.53 KiB) Viewed 7693 times

Finally here's a nice 'chromosome basket' caught with the trusty x100 that I like,

ws-labelled-single-1.jpg (175.06 KiB) Viewed 7693 times

As you can see, the possibilities are endless - luckily for me I have a never-ending supply of slides of my choosing!

[martinr]

Well, all I can say is I'm blown away by all those photos.

Thank you, John. Quite superb.

[martinr]

A couple more images,

Here's a nicely resolved pit-field in the cell-wall of a Xylem-ray cell with the 1.32 apo x100 that I really like a lot,
ws_x100 (1).jpg

I really like the detail here of the sectioned Lily pollen grain as seen with the 1.32 apo x100 also, great resolution of the tiny pore through the wall at the top of the grain...
ws_x100-with-na1_4-condense.jpg

Here is the same view with the water x50 with water between slide and objective, and just to see what would happen, oil between the 1.4 n.a. condenser and the slide-bottom - to me it looks easily as well resolved as the x100 oil...
ws_x50-W-obj-with-oiled-1_4.jpg

Finally here's a nice 'chromosome basket' caught with the trusty x100 that I like,
ws-labelled-single-1.jpg

As you can see, the possibilities are endless - luckily for me I have a never-ending supply of slides of my choosing!

I was going to ask you for any recommendations on website to help me make sense of the world of objectives, but I've found a site that probably takes quite some beating:

https://www.microscopyu.com/microscopy- ... ifications

and

https://www.microscopyu.com/microscopy- ... objectives

Martin

[MichaelG.]

Fascinating; I didn't know there was such a thing as water-immersion objectives.

Martin

.
I have no connection with the seller, nor any experience of this paticular model, but there are some 'New Old Stock' Russian water-immersion objectives currently on ebay:
https://rover.ebay.com/rover/0/0/0?mpre ... 2307135455

MichaelG.
.
P.S. ... The MicroscopyU page on W.I. objectives is very informative:
https://www.microscopyu.com/microscopy- ... objectives

[martinr]

Fascinating; I didn't know there was such a thing as water-immersion objectives.

Martin

.
I have no connection with the seller, nor any experience of this paticular model, but there are some 'New Old Stock' Russian water-immersion objectives currently on ebay:
https://rover.ebay.com/rover/0/0/0?mpre ... 2307135455

MichaelG.
.
P.S. ... The MicroscopyU page on W.I. objectives is very informative:
https://www.microscopyu.com/microscopy- ... objectives

Thank you; that article has clarified not only why water immersion is used, but also clarified some of the basics of optics as applied to microscopy.

Thanks too for taking the trouble to mention the ebay sale. Those objectives are for 160mm tube lengths and mine is 170mm. Even if they were 170mm I don't think they'd work on my 'scope as the Leitz Periplan eyepiece is matched to the Leitz objective, so I believe, correcting for some kind of aberration in the objective. Nevertheless, many thanks; at least I now know that LOMO is a Russian brand name and not yet another generic objective abbreviation to be mastered.