Search found 87 matches

by abednego1995
Sat Jan 30, 2021 4:07 pm
Forum: Equipment Discussions
Topic: Nikon MM objective object-sensor distance?
Replies: 4
Views: 595

Re: Nikon MM objective object-sensor distance?

Parfocal distance for the MM series is always 126mm.

Cheers,
John
by abednego1995
Sat Jan 23, 2021 9:16 am
Forum: Equipment Discussions
Topic: What the @&$% objective get
Replies: 14
Views: 1374

Re: What the @&$% objective get

Yup, you get the Sweaty Palm Syndrome handling these :-)

Nice demonstration of NA diff. Is that a ronchi grating??
by abednego1995
Fri Jan 22, 2021 6:05 pm
Forum: Equipment Discussions
Topic: What the @&$% objective get
Replies: 14
Views: 1374

Re: What the @&$% objective get

Lol, I’m sure you’ve seen the extreme spectrum of damaged objectives. The right one was NIB, the left with slight usage. I guess I was lucky with these:-)
by abednego1995
Fri Jan 22, 2021 5:08 pm
Forum: Equipment Discussions
Topic: What the @&$% objective get
Replies: 14
Views: 1374

Re: What the @&$% objective get

Great find! I wasn't aware of that label before.
btw, are these HR objectives reaching some kind of industry-wide end of life replacements? They're much more "affordable" than they used to be in numbers and price...
IMG_2054.jpg
well, I only needed one...but two is better!

Cheers,
John
by abednego1995
Sat Jan 16, 2021 10:32 pm
Forum: Equipment Discussions
Topic: Can someone tell me the difference between these two Nikon apos?
Replies: 14
Views: 1564

Re: Can someone tell me the difference between these two Nikon apos?

That silver PA20x is a CF series objective in production from 1976 to 1985. Pretty old, but good objective nonetheless. The black PA20x is a very recent finite objective made for a discrete slide scanner around 2013. It wasn't sold publicly and is rare. Excellent properties, but it lacks the spring ...
by abednego1995
Tue Oct 27, 2020 7:26 pm
Forum: Equipment Discussions
Topic: Please help me identify this Olympus OEM 60x objective
Replies: 8
Views: 2095

Re: Please help me identify this Olympus OEM 60x objective

No, "the outer shell".
The innards are probably Olympus.
I'm suggesting you got a poorly done Frankenobjektiv.

The outer shell of your lens is probably a lathed down shell of those Nikon OEM Illumina PA20x's.
by abednego1995
Tue Oct 27, 2020 6:36 pm
Forum: Equipment Discussions
Topic: Please help me identify this Olympus OEM 60x objective
Replies: 8
Views: 2095

Re: Please help me identify this Olympus OEM 60x objective

Perhaps its only me... but that outer shell on that "olympus" objective looks suspiciously Nikon... (Plus, you bought that for 5.7k USD??? My honest opinion, is you've been scammed. Who on the earth would wrap tin foil inside an objective to fit the outer shell?? That small screw on the case doesn't...
by abednego1995
Sat Oct 24, 2020 3:52 pm
Forum: Equipment Discussions
Topic: 10x Objectives: UPlanSApo 10x VS UPlanFL N 10x Ph1
Replies: 8
Views: 2146

Re: 10x Objective with delamination testing

With regards to the 100x, I can't get a nice view with adequate illumination due to what appears to be an internal aperture that blocks out the transmitted light. That's why you oil oil immersion objectives! It's impossible to introduce light into an oil immersion objective at an greater angle than...
by abednego1995
Sat Oct 24, 2020 6:13 am
Forum: Equipment Discussions
Topic: 10x Objectives: UPlanSApo 10x VS UPlanFL N 10x Ph1
Replies: 8
Views: 2146

Re: 10x Objective with delamination testing

Ok, first. About your UPlanSApo10x, you need to know where you're looking at. (i.e. which surface of whatever element) Here's the element positions assumed the patent is for the UPlanSApo10x. (US pat. US7158310B2) UPlanSApo10x.png What you were seeing in your blog, is the outer most periphery of the...
by abednego1995
Fri Oct 23, 2020 4:55 pm
Forum: Equipment Discussions
Topic: 10x Objectives: UPlanSApo 10x VS UPlanFL N 10x Ph1
Replies: 8
Views: 2146

Re: 10x Objective with delamination testing

Erm. No, Macro Cosmos... those spots you see in the objective aren't evidence of delamination. The edges of objective elements are painted black to lower internal reflection problems. Some spots on the rough glass has rubbed off showing the dots. Completely normal. They even show on new objectives. ...
by abednego1995
Mon Aug 24, 2020 5:23 pm
Forum: Equipment Discussions
Topic: Packing expensive objective lenses for shipping.
Replies: 15
Views: 4218

Re: Packing expensive objective lenses for shipping.

LoL, I've seen worse.
It's the bay, afterall. But seriously, you're buying 1k objectives from god knows who??
by abednego1995
Wed Jul 22, 2020 5:25 pm
Forum: Equipment Discussions
Topic: Nikon 2.5x M Plan vs. 40/2.8 Apo-Componon
Replies: 11
Views: 2507

Re: Nikon 2.5x M Plan

Low power objectives are difficult to design within their parfocal limits, and that doesn't help much with their image circle too. Used on a scope they'll perform as advertised.

Cheers,
John
by abednego1995
Sun Jul 05, 2020 3:37 am
Forum: Equipment Discussions
Topic: dummy sliders for Nikon DIC nosepiece
Replies: 1
Views: 1145

Re: dummy sliders for Nikon DIC nosepiece

Yes, those nosepieces had dedicated inserts for those opening, though not like the sliders. It rather resembles a flimsy wedge that just fits in the opening. The later inverted scope DIC nosepieces have plug shaped inserts, but not sure if it will fit the C-ND type DIC nosepiece. Cheers, John IMG_18...
by abednego1995
Tue Jun 30, 2020 6:04 pm
Forum: Equipment Discussions
Topic: Good polarizer to put in front of a macroscope / microscope lens?
Replies: 17
Views: 2666

Re: Good polarizer to put in front of a macroscope / microscope lens?

Just a musing... but if the WD of the objective is sufficient, shooting off a reflection on a plane piece of glass or someother dielectric reflective surface at its Brewster angle would give pol. Would become an awkward setup but as a possibility.

Cheers,
John
by abednego1995
Sun Jun 07, 2020 1:06 pm
Forum: Equipment Discussions
Topic: Are Nikon OEM 20x 0.75 objectives really UV enhanced?
Replies: 12
Views: 2037

Yup, Duke's comments pretty much nails it. UV transmission isn't the point with VC, axial chromatic abberation correction is. We use Fluors for better UV transmission, and if Nikon had "UV enhanced" Plan Apochromats in the first place that should have entered the market as the "dream objective" P.S....