Swift SW380B objective lenses problem

[jackieone]

I had ordered two lenses from AliExpress, a semi-plan 40x and an achromatic 4x lens. Before purchasing, I made sure the numbers on the lens barrels was identical to what was shown on my Swift SW380B lenses (4/0.10 160/0.17)

The 40x works but the 4x does not. When I contacted the seller they said I ordered a conjugate distance of 195 instead of 185, which is why the 4x lens does not work.

I searched all over the Swift manual, the Amazon blurbs, other microscope vendors blurbs, but found absolutely nothing on what conjugate distance is required for the Swift SW380B microscope.

Anybody have any information for me about this issue?

[jackieone]

Oh, I forgot: the 40x is being sold as a 195 conjugate and this is the one which works. The 4x advert (same vendor) doesn't say anything.

I've attached photos to compare the two. Besides the color, how would I know which is 185 and which is 195?

[MichaelG.]

I admit to being rather surprised that you can see no sign of an image at all … but this, by Oliver, is worth watching:
https://youtu.be/-4HzdclIW3A?feature=shared

MichaelG

[Scarodactyl]

I bet your new one is a short barrel. I have one that looks identical which is this way, if so it wants to it a lot lower than your other objectives. Mine also performs very badly.

[apochronaut]

Put a 10mm extension on it and see what it does. It would effectively be in a 170mm tube so the magnification would be slightly more. Can't return it, or it would be too expensive?

[MichaelG.]

Here’s a previous discussion, which might possibly be of interest:
viewtopic.php?t=7790

MichaelG.

[jackieone]

Thanks, everybody, for your responses.

@Michael G - that vid was spot on, as well as the discussion thread. I'd never heard about this before, so I didn't even know what to search for until I contacted the company/seller. I just tried again to use the "short barrel" lens, but the SW380B only goes down so far, and I can't get anything except as shown in the photo. Strange, right?

@apochronaut - Well, that's a workaround! The lens itself was not expensive, my problem is that with AliExpress once I agreed to free return for refund, I can't seem to find where to print the mailing label, and the seller has not sent me the link or the label, so I guess lesson learned. That's a minor annoyance but lesson learned!

@Scarodactyl - yes, sometimes I'm surprised by what works and what doesn't...for me, it's always a bit of a gamble.

[MichaelG.]

… I just tried again to use the "short barrel" lens, but the SW380B only goes down so far, and I can't get anything except as shown in the photo. Strange, right? …

.

Just for the sake of curiosity … try putting a slide on a couple of spacers about 10mm high [stacks of coins would do] and then see if you can get an image.

MichaelG.

[jackieone]

@Michael G - I would try that, but as I was adjusting the condenser on the SW380B, the light stopped transmitting to the slide. The bottom illumination is still on, but nothing is going through the condenser. I've just written to Swift asking for help, and I will post a separate forum question about this now. Gee willikers, if it isn't one thing, it's another...

[jackieone]

Swift Microscopes unfortunately does not reply to emails sent from their website.

The illumination thing happened several more times, and I returned it because nobody at Swift ever responded to my questions. Oh well.

Maybe there was something loose under there and I jarred it. The bottom of the lens has a little door which was open when I unwrapped it for the unboxing; I screwed the top back on, and I don't think that had anything to do with the condenser issue, but who knows...