WTB: Wild M8 0.4x auxiliary lens

[Scarodactyl]

Anyone have one handy they'd like to part with? I am happy to buy or swap.

[PeteM]

Stephen, a possible alternative source might be a 250mm surgical microscope lens. I found and am using one with the same 60mm x 1mm thread the M8 uses, marked only with the 250mm distance and "M1030." In practice, the working distance from the bottom of the lens is about 245mm, and the magnification is very nearly 0.4x.

It's a pleasure to work under (decent optics), but I haven't tried any photos through it.

[Scarodactyl]

I actually got a 250mm and a 150mm at a good price already but this is for a customer who didn't end up liking the optichrome objective I initially configured his scope with--too much nonplanarity/doming at lower mag, so I want to offer him a few alternatives to try. He's a good customer.

[Milou]

Hello,

Anybody knows if these lenses for Wild 690 (150mm to 300mm) are "plan" or achromatic ones?

And for a 150mm and a 170mm used as auxilliary lenses on a M8, what is their magnification coefficient?

Thank you

[Scarodactyl]

They are achromats, not plan, though planarity improves as you zoom in.
The reference focal length for an M8 is 100mm, so a 150mm givez 0.67x magnification, 200mm gives 0.5x etc.

[Milou]

Thank you Scarodactyl for your answer

[Rorschach]

I need to check if I have two of these M8 0.4x adapters. If yes, I could sell one of them.

[jfiresto]

I PMed Scarodactyl about one in mid-December and assume by then he had already found one. If anyone is looking for one on this side of the Atlantic, there is presently a like-new example on ebay.de for 249€ (+7€ shipping within Germany).

[Rorschach]

Ok, I won't dig through my stuff then.