Search found 1309 matches

by enricosavazzi
Mon Jun 08, 2020 11:16 pm
Forum: General Discussion Forum and Community Announcements
Topic: On Lockdown
Replies: 252
Views: 34694

Just in, a Nature study on the effects of lockdowns. They do have a large good effect and so far have prevented millions of deaths, but as the study says, we are still just at the beginning of the pandemic. The strategy of some governments of achieving herd immunity by allowing the virus to spread i...
by enricosavazzi
Tue Jun 02, 2020 11:02 am
Forum: Equipment Discussions
Topic: Beck 36x / 0.5 reflex objective
Replies: 8
Views: 1092

Perhaps you already know, but there are a few old papers (mid-20th century) dealing with reflective microscope objectives in UV, for example: https://onlinelibrary.wiley.com/doi/abs/10.1111/j.1365-2818.1953.tb02351.x?sid=nlm%3Apubmed https://pubmed.ncbi.nlm.nih.gov/13118588/ This one has sample imag...
by enricosavazzi
Tue May 19, 2020 7:34 am
Forum: Equipment Discussions
Topic: Comparing macro lenses using MTF - invitation, take 2
Replies: 26
Views: 4502

I have that Kodak scanner lens, it was sold for a very few dollars (maybe $10) by Surplus Shed. It would be the winner in any weight per dollar lens contest. If I recall correctly (and I may not be recalling correctly), it had lots of longitudinal CA in my tests, but maybe there is some range of m ...
by enricosavazzi
Sun May 17, 2020 2:53 am
Forum: Equipment Discussions
Topic: A peek inside the THK KR20
Replies: 6
Views: 1155

A peek inside the THK KR20

The THK KR20 linear actuator is not news to many of us. However, it may be interesting to peek inside and see a little of how it is built, especially since disassembling your KR20 just to see what is inside is "not recommended" (for good reasons). http://savazzi.net/photography/THK_KR20_inear_actuat...
by enricosavazzi
Mon May 11, 2020 12:41 am
Forum: General Discussion Forum and Community Announcements
Topic: On Lockdown
Replies: 252
Views: 34694

RP>> I said nothing about herd immunity. Checking the record , your exact words were "The downturns in the data are not due to whether a country went into lockdown, but due to the virus starting to run out of hosts to infect " (emphasis added). So I am puzzled. How is "run out of hosts" different f...
by enricosavazzi
Thu Apr 30, 2020 8:02 am
Forum: Equipment Discussions
Topic: Lens scope converter?
Replies: 4
Views: 1590

Just to make sure we are talking of the same thing, the "Nikon Lens Scope Converter" is an accessory that attaches at the rear of a Nikon lens with F bayonet and converts it to a telescope. It has an eyepiece at the rear and a built-in prism to erect the image. I had one in the past but sold it afte...
by enricosavazzi
Tue Apr 28, 2020 4:53 am
Forum: Equipment Exchange
Topic: WTB : Mitutoyo Mplan Apo X20 .42
Replies: 9
Views: 2277

I bought a Nikon ELWD 20x ,working distance: 19mm, it's great, as good as mitutoyo20x My Nikon finite MPlan ELWD 20x/0.40 has 10.1mm working distance. Wonder why the almost 9 mm difference between our lenses' WD? Could yours be the SLWD? Another possibility is that it is an ELWD, but used with a tu...
by enricosavazzi
Tue Apr 28, 2020 12:46 am
Forum: Equipment Discussions
Topic: Mitakon Super Macro 1x-5x (generation II)
Replies: 5
Views: 2870

For anyone that wants to pixel peep, here is a link to OneDrive that has a sampling of 13 pictures. https://1drv.ms/f/s!AvUX6lOYSxvraU-FAhs_h5dlX-E Appears that OneDrive lets you zoom in to about 140% Let me know if this works OK, or if you have issues using this method. Thanks, G Thank you for the...
by enricosavazzi
Sun Apr 26, 2020 8:14 am
Forum: Equipment Discussions
Topic: Stonemaster Stackmaster
Replies: 10
Views: 2708

Re: Stonemaster Stackmaster

lonepal wrote:It is strange.

How can they sell it without a global web site?
It could indicate that they are not interested in selling globally. Maybe the German market is enough for them.
by enricosavazzi
Sun Apr 26, 2020 2:36 am
Forum: Equipment Discussions
Topic: Stonemaster Stackmaster
Replies: 10
Views: 2708

Re: Stonemaster Stackmaster

Did a search and only found only one mention here to the Stackmaster rig (from 2017). Has anyone used this system and if so, any comments or critiques? I know nothing about it, but as a reference the Stackmaster is made/marketed by a company called Stonemaster, which also advertises lapidary equipm...
by enricosavazzi
Sat Apr 25, 2020 10:54 pm
Forum: Equipment Discussions
Topic: 40x LWD
Replies: 6
Views: 1987

[...] There are a few 40 LWD and ELWD from Nikon with 210 mm tube length and without cover glass. Some have > 2 mm free working distance. That would require a 50 mm intermediate tube being added to your microscope. [...] The MPLAN ELWD 40x 0.50 in particular has slightly more than 10 mm working dis...
by enricosavazzi
Sun Apr 19, 2020 12:03 pm
Forum: Equipment Discussions
Topic: What are Zeiss Jena HI finite objectives?
Replies: 3
Views: 2147

Thanks for the information. Given the relatively low NA, I was actually hoping for a water or glycerol immersion objective, as a speedier and less messy alternative to oil immersion. I have a Lomo 70x water immersion objective that I might try to use instead.
by enricosavazzi
Sat Apr 18, 2020 8:31 am
Forum: Macro and Micro Technique and Technical Discussions
Topic: Polyvar condenser problem.I need advise.
Replies: 5
Views: 2811

Re: Polyvar condenser problem.I need advise.

[...]This is true with small Standards stands but with the WL I can raise both the stage holder and condenser holder in the focus block to work with short barrel objectives. Sharing these components with the WL, I think that Universal and Photomic would be able to do the same I got rid of my Photom...
by enricosavazzi
Sat Apr 18, 2020 12:26 am
Forum: Macro and Micro Technique and Technical Discussions
Topic: Polyvar condenser problem.I need advise.
Replies: 5
Views: 2811

Re: Polyvar condenser problem.I need advise.

Hi I have a biological microscope Reichert Polyvar with a universal condenser BF, DF, PH, DIC. The problem is that I can't adjust the lighting according to Kohler. I proceed in this way: I leave the condenser down, close the field iris diaphragm, then raise the condenser up and when I see that ther...
by enricosavazzi
Fri Apr 17, 2020 1:04 am
Forum: Equipment Discussions
Topic: Bellows for Canon EOS
Replies: 18
Views: 3702

[...] The Ihagee bellows seems to work very much like my large Pentacon M42 bellows, see e.g. https://www.photomacrography.net/forum/viewtopic.php?p=37898 [...] Are there any specific reason you prefer the Ihagee-branded version? The M42-threaded bellows must be a lot easier to adapt. By the way, i...