Joined: Fri May 12, 2006 11:24 am Posts: 7523 Location: Rome, Italy
hi folks,
here a WILD 450 scope.
It's the 1st time i post one, i guess it could be a good option if only the price will remain decent. i could do a snipe on it so, if someone else is interested it would be good to behave like gentlemans and not fight among ourselfs. i'll be glad to not bid if someone here would have a reasoned chance.
ciao
alberto
Joined: Tue Oct 20, 2009 3:34 pm Posts: 381 Location: Sweden
Alberto wrote:
AGAIN, did you asked DIRECTLY to the vendor?
Noop! I didn´t, but as I writed - I can´t afford it right now that´s why I didn´t ask! And the last time I asked a vendor I recieved a mail with one word in - "NO!" After a second mail I recieved - nothing!
Joined: Wed Feb 25, 2009 5:53 pm Posts: 175 Location: Toronto
I'm thinking I might take a swing at this bad boy.... I have no problem taking my photos through the ocular, since thats what I've been doing all this time already.
Joined: Thu Dec 13, 2007 3:42 pm Posts: 4091 Location: the Netherlands
thresh wrote:
I'm thinking I might take a swing at this bad boy.... I have no problem taking my photos through the ocular, since thats what I've been doing all this time already.
It's not ideal though... IMO the whole M450 concept is not gemmo oriented. It was brought out together with the M400 or shortly after it in 1976 if I'm not mistaking as an industrial inspection scope. The built in coaxial illuminator is useless for gemology. With a bit of patience an M400 or M420 can be bought as well.
That said, it will have awesome optics and you will be able to look at rocks from up close. Getting that scope for cheap would be worth a party.
Joined: Wed Feb 25, 2009 5:53 pm Posts: 175 Location: Toronto
Hmmm... Rigging up my own lighting/acquiring a different base is not something I have too much issue with. So I have the same question:
What are the other problems w/ the 450? The distance between focal point and stone? I'm assuming it's a 10x-50x w/ 10x lenses? Not Plano-Apo or something?
The differences Alberto mentions are about it, with one other difference.
Some M450s came with an objective lens called an EpiZoom. This is pretty much a MakroZoom with a 2x front element. Its working distance is a bit close and its mag a bit high for our purposes.
I don't agree that a vertical illuminator is useless for gemology but Tim holds that opinion strongly. But I do tend to think of scopes in a broader context so he may be right.
I agree that getting it cheaply would be worth a party. As a matter of fact I bid on it as soon as I saw it. But was out bid. I will not bid again on this one though I think it would be a great deal up to $800 or one thousand dollars.
Last edited by G4Lab on Wed Jan 13, 2010 10:49 am, edited 1 time in total.
Joined: Thu Dec 13, 2007 3:42 pm Posts: 4091 Location: the Netherlands
Albè,
apart from the lack of port (and beam splitting prism & knob) and the presence of the built in coaxial illum. there is no differences. Exact same thing but built for a different purpose: inspection only.
Not my purpose... I bought the M400 because it is a photomakroskop and it does a awesome job as such. Remove the photo bit and you end up with a 'just' makroskop... I would rather have a stereoscope in that case...
Jeff,
it's the standard macrozoom 1:5 objective with its focal point at about 102mm, if it had an APOzoom objective under it I would be in the race too
But again... if photos aren't your thing anyway, you are handy enough to rig up a base for it and you just want great optics: go for it...
thresh, a brief lesson in objectives. IF you had a really high NA objective, then focused light you see originates from some 2-D surface that is not necessarily a plane. Imagine a piece of construction paper bowed so that it is higher in the middle and lower at the edges. Then bow it along the perpendicular edges. This represents somewhat the surface in focus. Objective makers would prefer this focal surface to be a plane, the so-called "flat field". From the construction paper analogy, in this case the sheet of paper is flat.
With the long-working distance objectives of gem microscopes, they have low NA, and so there is some depth of focus. Even so, microscopic users would still prefer the flat field condition to apply.
Standard objectives have the worst flat field. Apo lenses are middling. And plan-apo are the ultimate... you get flat field everywhere except at the corners of a square. And since you are viewing a circular image, it hardly shows up at all.
As to how this flat field affects the users... it is debatable. You pay a lot, lot more for each step up. In gem microscopy and photography, the depth of focus is so thick that you may not even be able to notice the difference. On the other hand, in my "high NA" work, it is absolutely critical to work with plan apo.
And to think I never intended to know the details of microscopes inside and out, upside down, and (especially!) sideways. As a kid, I always thought they were junk, and as a result I avoided all optics courses in college and graduate school.
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