MicrobeHunter.com Microscopy Forum

Hi,

I have the chance to buy a Leitz Wetzlar 40 x, long achromat objective with correcting collar, to replace the very poor quality objective of my entry-level scope. The seller claims it to be in very good condition. Is this a good purchase at around 90 US? Is it a very old model? Any other thing to consider? I know the brand is great, but I don't know much about their specifics products.

Regarding the price, beware that the local microscopy market is extremely small around here, so even used stuff is highly overpriced compared to bigger markets.

TIA for your help.

Probably not the best choice unless your "entry level" scope is a Leitz and you have the proper correcting eyepieces to go with it. It also may not be plan. What scope and 40x objective do you have?

Thank you, Pete.

To be honest, I'm currently not using a 40 x objective. I bought an entry-level scope a while ago, with quite bad short achromats objectives. I can tell they are quite bad because a few months ago I bought a generic 20 x achromat and I was amazed by the difference shown both in sharpness and color rendition, and the 20 x is not a fancy objective at all.

Since the new objective was long, I managed to insert the 4x lens on the 40 x barrel to make the 4 x and the new 20 x almost parfocal. So for a while, I have been using and enjoying a lot this 40 x - 200 x scope. I did keep the short 100 x, but I almost never use it.

I thought this Leitz was a good opportunity to get a good 40 x, but it seems it is not.

I forgot to add that I'm sure it's not a plan, but I'm not looking for such an objective.

I would expect a Leitz achromat to be good. It might start getting tricky (edit IF) none of your objectives are parfocal.

I was expecting the 20 x and the new 40 x to have a parfocality of 45 mm... right?

I believe that's right. Newer Leitz have 45mm parfocal distance.

Hi Javier,
the objective will be from the mid to late 80s. The knurled ring is no correction collar. There sas a series of EF achromats, "extended field" = semiplan, but this seems to be an even simpler basic achromat. It will probably be a good objective for your needs though.
When looking at the asked price and your microscope it might be better to save for a while and buy a complete better microscope. Even with overseas shipping and import duties you might get a better price / value ratio.

Bob

Thank you, Bram and Bob.

I didn't expect it to be such an old model. I don't know what to expect from an optic that might have +35 years old. I think I'm going to pass on this one.

I have been wondering about what Bob says of saving for a new scope. The thing is that from my research so far, more expensive microscopes (around US 400 - 600) still feature achromatic objectives, very much like my 20 x. I understand I shouldn't expect to gain image quality with those ones. On the other hand, the Motic B210 is selling at a good price at around 1250 US, but I'm not willing to pay that much for a scope anytime soon.

On the used market there are quite a few Nikon, Zeiss, and Olympus microscopes, but I' don't feel comfortable making a big investment on a used scope at this point, as inexperienced as I am. Maybe my best option is to stick with this scope for now and try to get some brand new 10 and 40 x achromat objectives, similar to the 20 x.

Hey the 80s is pretty new! The optics on this '42 B&L are still really good.

That is impressive.

Don't give up hope on the Nikon. I will be tackling it tomorrow evening.

apologies. I confused you with another Javier on the forum.

You should not spend more for the Leitz objective. If you need another objective, just buy Amscope or similar, and return if you don't like it. If you can get one from the same series as that generic you like, they should be parfocal, which is a bonus. One of my microscopes is an 80s-era Leitz microscope with achromatic objectives, and I was surprised to find that a cheap Amscope 20x achromatic objective seems to perform quite well. I have it between the 10x and 40x Leitz objectives and I can't really see the difference in quality (they are also almost parfocal). Now if I had younger eyes or more modern very wide field eyepieces, I might see differences around the edges, but for this microscope and me it works just fine.

For just visual use you can get away with a lot of partial incompatibility. My friend's PI has a pair if Leitz laborluxes with olympus, leitz, zeiss, wild and nikon objectives on thrm, and really only the Nikon is visually compromised by the corrections mismatch (parfocality is off but not too bad). Photography is another matter, as the aberrations are much more visible, but for his purposes the results are good enough.