Several months ago I got the Viltrox M3/4 extension tube set (10 mm and 16 mm) and a no-name set externally quite similar to the Kenko (all visible details are the same judging from pictures and videos of the Kenko tubes, but I don't have Kenko tubes for a direct comparison of measurements). In both...

I need a refresher - What does "HI" mean in the engravings on Zeiss Jena finite objectives? I have for example a Zeiss Jena Apochromat HI 60x with adjustable NA from 0.7 to 1.0, in RMS mount.

I have no specific knowledge to offer, but I have a Mitutoyo FS-60 microscope equipped with four Mitutoyo M Plan Apos, and I rarely use the built-in axial illumination because it gives a very flat and very low contrast "rabbit-in-the-headlights" rendering of almost all subjects. It is especially hop...

A water aspirator connected to a running water faucet is probably the simplest and cheapest way to achieve a relatively good vacuum: https://en.wikipedia.org/wiki/Aspirator_(pump)

With moderately porous rocks, the bubbles that emerge from the rock surface may be air being replaced by water drawn into the rock pores by capillarity. These bubbles can be largely eliminated by submerging the subject in water, then applying a vacuum (or a substantially reduced atmospheric pressure...

In one of my junk boxes I happen to have two very similar or identical Mitutoyo micrometers, also in my case from the stage of an SEM. I don't remember the SEM brand, but not Mitutoyo, The micrometers only are Mitutoyo. I also have a third micrometer from the same stage, but it is smaller than the o...

Are those rice grains on the ground?

Sony has released a camera remote SDK for Alpha cameras. So far it only supports ILCE-7RM4 and ILCE-9M2, they say they will support more, but it is unclear whether they will support also legacy models or only present/future ones. Only Windows 8.1 and Windows 10 64-bit supported. Only USB to the came...

[...] I had come across some interesting adapters such as the one below on eBay but I could never work out if both ends with M52 threaded or only one end was. https://www.ebay.co.uk/itm/52mm-Lens-Adapter-Tube-for-Kodak-P850/401209832846 Difficult to say for sure, but this part is generally describe...

From the inventory of a seller currently advertising a few fairly reasonably priced scanner lenses, the following item stands out in more than one way:

https://www.ebay.co.uk/itm/Razor/223865 ... SwqCJbzit-

[...]The Laowa 60mm 2x for dslrs cover FX when being used as a macro lens.[...] It does cover full frame in the macro range, but at the expense of dark corners at all apertures, substantial transversal CA and major pincushion distortion. Pincushion distortion is still quite obvious on APS-C as well...

So, there is no possibility to align anything.[...] One of the types of alignment that may be done is by rotating elements with respect to each other, while measuring the optical parameters to find the best reciprocal orientation. This type of alignment may be done at the factory before inserting t...

[...] I can't find any tubes that thread into the front of the lens. People complain about ordering the extension tubes from China and not getting them for 8 weeks or more. Sounds ridiculous.[...] Unfortunately true, it usually takes 1-2 months. I googled 58 mm extension tubes and found some on Ama...

I will have to buy more extension tubes to move the ES-1 further from the front of the 90mm f2.8 Macro OSS lens. I can't focus it with the ES-1. I may end up using my Nikon PB-6 Bellows and the slide adapter after all. All the additional extension tubes and rings may cost as much as the PS-6 slide ...

Would I be able to do this with the Sony 90mm f2.8 Macro OSS lens and an extention tube on the end of the lens? This lens focuses internally down to 1:1. I have read that it actually becomes a 70mm lens when it is focused past 1:4. Photographers have complained about the lens changing focal length ...