Search found 4949 matches

by Lou Jost
Mon Jun 14, 2021 7:55 am
Forum: General Discussion Forum and Community Announcements
Topic: Forum now provides searching by word sequences
Replies: 3
Views: 48

Re: Forum now provides searching by word sequences

Thanks for doing this, Rik. It greatly improves the functionality of this wonderful forum.
by Lou Jost
Sun Jun 13, 2021 5:53 am
Forum: Equipment Discussions
Topic: Nikon Fluorophot information?
Replies: 0
Views: 55

Nikon Fluorophot information?

On eBay I found an old Fluorophot fluorescence head complete with five or six filter cubes. Does anyone have any information about these cubes? They have no wavelength information written on them. The device itself looks quaint, but it has a nice variety of colored cubes. Thanks in advance,
Lou
by Lou Jost
Sun Jun 13, 2021 4:39 am
Forum: Technical and Studio Photography -- Macro and Close-up
Topic: Scorpion fly male - Panorpa communis
Replies: 11
Views: 155

Re: Scorpion fly male - Panorpa communis

Thanks Pawel. I am a bit confused, you wrote "10x 0.45" but the link goes to a 10x 0.25. The price you quote seems more appropriate for the 10x 0.25.
by Lou Jost
Sat Jun 12, 2021 6:45 pm
Forum: Technical and Studio Photography -- Macro and Close-up
Topic: Scorpion fly male - Panorpa communis
Replies: 11
Views: 155

Re: Scorpion fly male - Panorpa communis

Yes, wonderful photos of a very strange insect. Which Nikon PlanApo 10x was that?
by Lou Jost
Thu Jun 10, 2021 9:52 am
Forum: General Discussion Forum and Community Announcements
Topic: use Bing to search PMN
Replies: 5
Views: 131

Re: use Bing to search PMN

Wow, that is excellent! Thanks for doing that upgrade, it will make it easier to search for topics which consist of common words in uncommon combinations.
by Lou Jost
Thu Jun 10, 2021 7:13 am
Forum: General Discussion Forum and Community Announcements
Topic: use Bing to search PMN
Replies: 5
Views: 131

Re: use Bing to search PMN

That's unfortunate; I had in the past found Google to work much better than the internal search feature. I can't get the internal engine to search for an exact word series; for example, a search for "Minolta enlarger" finds all posts with both the words "Minolta" and "enlarger" somewhere in them, in...
by Lou Jost
Thu Jun 10, 2021 6:22 am
Forum: Equipment Discussions
Topic: Tube Lens tests - medium format and full frame
Replies: 48
Views: 16150

Re: Tube Lens tests - medium format and full frame

Nathanm sadly has not been posting much these days (none since 2017). I miss his posts. Perhaps he will answer, but if not, I would like to suggest a work-around. When I have this situation, I use multiple step-down rings, some mounted INSIDE the outer ones. This can bring an objective as close as y...
by Lou Jost
Mon Jun 07, 2021 9:00 pm
Forum: Equipment Discussions
Topic: How super is the Olympus superapo?
Replies: 11
Views: 330

Re: How super is the Olympus superapo?

That new test nicely shows the excess CA in the Fluor.
by Lou Jost
Mon Jun 07, 2021 6:35 pm
Forum: Equipment Discussions
Topic: How super is the Olympus superapo?
Replies: 11
Views: 330

Re: How super is the Olympus superapo?

Don't you think the difference might mostly be due to the huge difference in NA between those two?
by Lou Jost
Mon Jun 07, 2021 7:57 am
Forum: Equipment Discussions
Topic: Does anyone have the Laowa 100mm x2 macro lens?
Replies: 36
Views: 5904

Re: Does anyone have the Laowa 100mm x2 macro lens?

but I'm pretty sure that coupled lens setup was under 40mm, possibly closer to 35mm. So unless that Laowa spec is wrong, they are not close at all. Yes, I see that the working distance for the Laowa is a lot better than for the lens combo. Lens combos have a flange-to-subject distance equal to the ...
by Lou Jost
Sun Jun 06, 2021 8:53 pm
Forum: Equipment Discussions
Topic: Does anyone have the Laowa 100mm x2 macro lens?
Replies: 36
Views: 5904

Re: Does anyone have the Laowa 100mm x2 macro lens?

I had a Nikon 105mm AFD and a Nikon 55mm f/3.5 manual lens (55mm was reversed, used the 105mm for coupling)
I've often wondered about that combination. How was it at nominal m (1.9x)? Working distance would have been 46mm, similar to that of the Laowa.
by Lou Jost
Sun Jun 06, 2021 2:22 pm
Forum: Equipment Discussions
Topic: Qioptiq d.fine HR 2.4/128 3.33x Lens Test is Online
Replies: 7
Views: 195

Re: Qioptiq d.fine HR 2.4/128 3.33x Lens Test is Online

it is very exciting to see such a perfect lens. I hope that before I die it will appear on the used market. In your website's review, you mentioned that the new lens was designed to take into account the sensor filter pack thickness, and you said: Technically this should give a newer lens an advanta...
by Lou Jost
Sun Jun 06, 2021 11:25 am
Forum: Equipment Discussions
Topic: Does anyone have the Laowa 100mm x2 macro lens?
Replies: 36
Views: 5904

Re: Does anyone have the Laowa 100mm x2 macro lens?

The 70mm Art lens is difficult to reverse, because the inner (recessed) front lens housing has the threads.

Didn't mean to offend the great people at Cosina by calling their lens "ordinary" :wink:
by Lou Jost
Sun Jun 06, 2021 9:05 am
Forum: Equipment Discussions
Topic: Does anyone have the Laowa 100mm x2 macro lens?
Replies: 36
Views: 5904

Re: Does anyone have the Laowa 100mm x2 macro lens?

I would suggest trying it against a reversed ordinary macro lens set to 1:2, like the Cosina 65mm. Even better would be to use a reversed 60mm Olympus macro lens set to 1:2
by Lou Jost
Sun Jun 06, 2021 5:45 am
Forum: Macro and Micro Technique and Technical Discussions
Topic: On the odd aspects of how light Really works...
Replies: 2
Views: 141

Re: On the odd aspects of how light Really works...

Feynman was a great explainer, even for basic classical physics. We used his Lectures series as a textbook in introductory physics. Regarding QED, my favorite part of Feynman's viewpoint is that antiparticles are ordinary particles going backwards in time. When a particle and antiparticle appear to ...