Search found 2880 matches

by Chris S.
Fri Oct 23, 2020 8:43 pm
Forum: Equipment Discussions
Topic: Out, out ##### spots!
Replies: 10
Views: 103

Re: Out, out ##### spots!

Btw, can I use my normal camera lens cleaning fluid and lens tissue (PecPad) on an objective? Good enough for my 600mm, but maybe that's not relevant either. ;-) I don't know what's in your normal lens cleaning fluid. I use ethyl or isopropyl alcohol for cleaning lenses, or if a lens is very grungy...
by Chris S.
Fri Oct 23, 2020 5:20 pm
Forum: Equipment Discussions
Topic: Out, out ##### spots!
Replies: 10
Views: 103

Re: Out, out ##### spots!

Thanks, Chris. (I've also got the 20x ;-)) Dennis, I didn't mention your 20x, because a 20/0.42 equates to f/24--revealing of dust, but not so ruthlessly as your 50x(f/45) or 100x (f/71). It's those tiny effective apertures that make dust appear in focus on your sensor. In modern, regular photograp...
by Chris S.
Fri Oct 23, 2020 4:50 pm
Forum: Equipment Discussions
Topic: Mitutoyo QV 3d Usage
Replies: 4
Views: 181

Re: Mitutoyo QV 3d Usage

https://zookeys.pensoft.net/article/24584/ That article is well-worth a look--particularly the supplemental document that goes into wonderful detail on the how and why of each element in the design and processing. I thought of the QV or the Nikon Measuring, you can think of other telezentic lenses ...
by Chris S.
Fri Oct 23, 2020 12:31 pm
Forum: Equipment Discussions
Topic: Out, out ##### spots!
Replies: 10
Views: 103

Re: Out, out ##### spots!

My guess is that it's sensor dust. You didn't mention which objective you're seeing this with, but I know that you have objectives that are effectively f/71 (Mitutoyo 100/0.70) and f/45 (Mitutoyo 50/0.55). These are ruthlessly revealing of sensor dust. I clean camera sensors under a stereo microscop...
by Chris S.
Tue Oct 20, 2020 11:45 pm
Forum: Macro and Micro Technique and Technical Discussions
Topic: Laser aiming and focus in photomacrography
Replies: 35
Views: 41377

Re: Laser aiming and focus in photomacrography

Pau, what an elegant implementation! :D Thanks for posting it. Looks like a great approach for Canon bodies with similar eyepieces. I'd not heard of "12mm diameter plastic tube wall fixation." Am glad to be aware of it now. At present, I'm working on a version for another forum member. When finished...
by Chris S.
Fri Oct 16, 2020 8:44 pm
Forum: Equipment Discussions
Topic: New Mitutoyo apo 10x
Replies: 48
Views: 1460

Re: New Mitutoyo apo 10x

(FYI, the "-2" I'm referring to is indicated on the objective canister, you can see it suffixed to the model number, -2 is the second version. Newest versions have the -3 tag". While the canister clearly does say "-2", it also appears to say "5x" (though it's fuzzy in the image). If so, this is not...
by Chris S.
Thu Oct 15, 2020 10:34 pm
Forum: Equipment Discussions
Topic: New Mitutoyo apo 10x
Replies: 48
Views: 1460

Re: New Mitutoyo apo 10x

Many forum members are starting to get standardized wafers as resolution targets, and this will give us the ability to test and compare our objectives against a common standard. Lou, I'm less than optimistic about the usefulness of distributed testing on standardized wafers, for a bunch of reasons ...
by Chris S.
Wed Oct 14, 2020 8:48 pm
Forum: Equipment Discussions
Topic: New Mitutoyo apo 10x
Replies: 48
Views: 1460

Re: New Mitutoyo apo 10x

First the good news: I've tested more Mitutoyo objectives than I can count, and inspected all of them visually as a first step. I see nothing unusual or disturbing shown in any of the images you've posted. Now the bad news: The visual appearance of a Mitutoyo objective tells you very little. I did o...
by Chris S.
Mon Oct 12, 2020 9:50 pm
Forum: Equipment Discussions
Topic: Canon EOS RP + Sigma 150mm Macro + Nikon CFI Plan 10x
Replies: 4
Views: 303

Re: Canon EOS RP + Sigma 150mm Macro + Nikon CFI Plan 10x

Nice demo! :D

I had to look up jaggery, as I'd never heard of it. Sounds tasty.

--Chris S.
by Chris S.
Sun Sep 27, 2020 7:57 pm
Forum: Macro and Micro Technique and Technical Discussions
Topic: Mitutoyo blemishes... or inflated expectations?
Replies: 7
Views: 544

Re: Mitutoyo blemishes... or inflated expectations?

Lou, Agreed that if this lens has been disassembled, it's junk. However, from the images Greg linked to, I'm not sure that anyone has disassembled this lens. Looking into an objective can fool the eye (or at least my eyes)--things are not always in the location they appear to be. I wouldn't condemn ...
by Chris S.
Sun Sep 27, 2020 7:19 pm
Forum: Macro and Micro Technique and Technical Discussions
Topic: Mitutoyo blemishes... or inflated expectations?
Replies: 7
Views: 544

Re: Mitutoyo blemishes... or inflated expectations?

Greg, I don't see anything in your documentation that would be an obvious cause of significant image degradation. Take a look, for example, at Mitutoyo 50x with chips in glass, tested . This said, even a cosmetically impeccable Mitutoyo objective can be an optical disaster. Also, I wouldn't expect a...
by Chris S.
Sat Sep 26, 2020 11:28 pm
Forum: Macro and Micro Technique and Technical Discussions
Topic: Laser aiming and focus in photomacrography
Replies: 35
Views: 41377

Re: Laser aiming and focus in photomacrography

Iconoclastica, The 3V diode draws maximally 45mA, so the max power uptake is 135mW. Does this need a cooling body? The design could remain much simpler and more compact if the housing could be left out. Or perhaps replaced with a tightly fitting piece of aluminium tube. Agreed that this small laser ...
by Chris S.
Thu Sep 24, 2020 1:56 pm
Forum: Equipment Discussions
Topic: Mitty M Plan Apo 100x/0.70 WD 6
Replies: 4
Views: 566

Re: Mitty M Plan Apo 100x/0.70 WD 6

Lou Jost wrote:
Thu Sep 24, 2020 5:40 am
I imagine the 100x is nearly telecentric? If so, you could stitch four of its images and duplicate the FOV of the 50x but at a 25% higher resolution.
It can be treated as "effectively telecentric," as the depth of field is exceedingly shallow. So yes, I think stitching could work with it.
by Chris S.
Wed Sep 23, 2020 11:44 pm
Forum: Macro and Micro Technique and Technical Discussions
Topic: Laser aiming and focus in photomacrography
Replies: 35
Views: 41377

Re: Laser aiming and focus in photomacrography

I've taken far too long to reply--my apologies. Family health issues intervened. In this implementation, there is no danger of the laser hurting the sensor. Let me explain. In the configuration presented in this thread, the light from the laser never has a chance to reach the sensor in any damaging ...
by Chris S.
Wed Sep 23, 2020 11:12 pm
Forum: Equipment Discussions
Topic: Mitty M Plan Apo 100x/0.70 WD 6
Replies: 4
Views: 566

Re: Mitty M Plan Apo 100x/0.70 WD 6

Pawel, I use both the Mitutoyo 50x/0.55 and the 100x/0.70. I’ve also tested other people’s specimens of both lenses, so know that my particular lenses are good ones. However, I don’t have examples of stacks at hand that I’m at liberty to share. When my interest is supporting scientific study or sati...