Has anyone used Olympus Microscope Lens Si Apo 40/1.00F?

[osterport]

The NA of this one is quite high, not sure if the resolution is good, but the price is quite ok. Looks like it's RMS interface, should be compatible with most microscopes.
This picture below is just an example



Anyone ever used it? How does it perform?

[apochronaut]

It is silicone immersion but if you can pull that off the image quality will be quite high with the following provisos. It is messy.

I have not used that objective but there are some characteristics of the short barrel Olympus objectives that one would need to be aware of before considering using one. While they are a standard 160mm finite tube objective , the parfocal length is a unique 36.65 mm, making them only parfocal with other short barrel Olympus objectives. You could also use it mixed with a few other objectives : U.S.A. made Bausch & Lomb 160mm apochromat objectives and those made for the Bausch & Lomb Galen I microscope, however the SI requirement would make mixing it with dry or oil objectives, pretty annoying.
The other thing about them that bears note is that they require a high degree of compensation in the eyepiece, more than most other 160mm Apos.Without that degree of compensation , for instance if you tried to use them with any number of eyepieces that had a more neutral character, even Olympus eyepieces made for the long barrel 160mm objectives , there will be residual over correction resulting in an undesirable level of peripheral ca, and most likely some field curvature.

With the correct Olympus Bi 10X eyepieces they will be plan to only an 18mm f.o.v.

I think there is an old thread related to this same objective, you could try to look up.

[zzffnn]

I did research on that objective. A microscopist reported that the performance of that objective is mediocre. He reported that on Facebook in an Olympus Microscope group, if I remember correctly. Please search there.

[viktor j nilsson]

viewtopic.php?t=11654

Here's my earlier thread about it. In short, silicone immersion does have a theoretical advantage over regular oil with deeper mounts. However, silicone oil is super messy. And the APO40 SI F is not super good. It's still a very old design, and at the time, the use of silicone oil wasn't so much about maximizing resolution and minimizing aberrations (as in today's offerings) as it was about avoiding auto fluorescence - the available immersion oils at the time were auto fluorescent, while silicone oil is not.

After my first tests of the 40x SI and 100x SI objectives, I haven't used them at all. Too much of a hassle for very little gain. I much prefer my other oil objectives, especially my Nikon CF Fluor 40x 1.30 which is better in all respects, and a joy to use.

I still thought it was fun to test them, might return to them one day.

Also, in addition to the short parfocal distance, the position of the intermediate image is not the standard 10mm, but something like 13mm down the tube. Definitely not easy to mix and match with objectives and eyepieces from other makers.

[zzffnn]

Viktor, you were the microscopist who inspired me to look into those silicone immersion objectives! Now I remember.

I like that SI100 and SI40 both have iris and that they can work with glycerol/water mixture. I would not use silicone oil for immersion at all; yes, it is way too difficult to remove.

So from your experience, the theoretical advantage of “seeing deeper into thick water mounts” does not exist, when compared to your Nikon CF Fluor 40x 1.30?

Thank you.

[osterport]

It is silicone immersion but if you can pull that off the image quality will be quite high with the following provisos. It is messy.

I have not used that objective but there are some characteristics of the short barrel Olympus objectives that one would need to be aware of before considering using one. While they are a standard 160mm finite tube objective , the parfocal length is a unique 36.65 mm, making them only parfocal with other short barrel Olympus objectives. You could also use it mixed with a few other objectives : U.S.A. made Bausch & Lomb 160mm apochromat objectives and those made for the Bausch & Lomb Galen I microscope, however the SI requirement would make mixing it with dry or oil objectives, pretty annoying.
The other thing about them that bears note is that they require a high degree of compensation in the eyepiece, more than most other 160mm Apos.Without that degree of compensation , for instance if you tried to use them with any number of eyepieces that had a more neutral character, even Olympus eyepieces made for the long barrel 160mm objectives , there will be residual over correction resulting in an undesirable level of peripheral ca, and most likely some field curvature.

With the correct Olympus Bi 10X eyepieces they will be plan to only an 18mm f.o.v.

I think there is an old thread related to this same objective, you could try to look up.

Thanks, I would skip this one as I do not have the eyepieces at all.