Search found 17863 matches

by rjlittlefield
Tue Oct 27, 2020 8:22 pm
Forum: Photography Through the Microscope
Topic: Porcupine quill
Replies: 6
Views: 77

Re: Porcupine quill

Macro_Cosmos wrote:
Tue Oct 27, 2020 5:26 am
100x objective mag, DIC. More info and bigger here: https://flic.kr/p/2jZFm1b
Lou Jost wrote:
Tue Oct 27, 2020 2:49 pm
I am puzzled, the scale seems way off if this is the cross section of a porcupine quill.
Looks like a typo. The Flickr posting says 10X objective, 9 images stitched.

--Rik
by rjlittlefield
Fri Oct 23, 2020 6:52 pm
Forum: Technical and Studio Photography -- Macro and Close-up
Topic: Fluorite with masking tape
Replies: 12
Views: 1062

Re: Fluorite with masking tape

Interesting -- and it's not every day I learn a new word with only three letters!

--Rik
by rjlittlefield
Fri Oct 23, 2020 6:18 pm
Forum: Equipment Discussions
Topic: Out, out ##### spots!
Replies: 13
Views: 273

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

If that last image is a whole frame, shrunk to fit the forum, then I'm going out on a limb and suggest that maybe it's dust on the rear element of the 200 mm telephoto. I'd expect anything on the sensor to look a lot sharper under that condition. It's very unlikely to be anywhere on or in the objec...
by rjlittlefield
Fri Oct 23, 2020 10:14 am
Forum: Equipment Discussions
Topic: Olympus BH2 Condenser Mount
Replies: 29
Views: 2611

Re: Olympus BH2 Condenser Mount

difficulty of getting digital calliper blades into the right angle made by the dovetail with the base of the condenser. The standard way around this difficulty is shown at https://www.engineersedge.com/mechanical,045tolerances/measuring_and_designing_dovetail_slides_14212.htm : https://www.engineer...
by rjlittlefield
Wed Oct 21, 2020 9:26 am
Forum: Technical and Studio Photography -- Macro and Close-up
Topic: qDslrDashboard & Zerene Stacker compatibility
Replies: 2
Views: 96

Re: qDslrDashboard & Zerene Stacker compatibility

I assume that you're referring to the ASDF shortcut keys for the StackShot controller panel inside Zerene Stacker. Those will work only when the StackShot controller panel has keyboard focus. If you mouseclick anywhere outside that panel, then whatever you clicked on will get keyboard focus, and the...
by rjlittlefield
Mon Oct 19, 2020 3:42 pm
Forum: Technical and Studio Photography -- Macro and Close-up
Topic: jewel beetle stitch
Replies: 7
Views: 543

Re: jewel beetle stitch

interesting image, looks like the claws have gone missing on both feet.

--Rik
by rjlittlefield
Sat Oct 17, 2020 6:38 pm
Forum: Technical and Studio Photography -- Macro and Close-up
Topic: Flies with Olympus 22.5mm f3.5
Replies: 7
Views: 334

Re: Flies with Olympus 22.5mm f3.5

optimized for looking through thick glass. That would be very interesting and useful! Well, it's just a wild guess. But I have used microfilm/microfiche readers that had carrier plates maybe 5 mm thick, and the text on screen looked good everywhere. Working distance on those readers was pretty shor...
by rjlittlefield
Sat Oct 17, 2020 6:01 pm
Forum: Technical and Studio Photography -- Macro and Close-up
Topic: Flies with Olympus 22.5mm f3.5
Replies: 7
Views: 334

Re: Flies with Olympus 22.5mm f3.5

That's an unusual level of precision on the focal length: 22.25 mm. Seems like it must have been made for some very specific purpose.

My wild guess would be that it's a microfilm/microfiche lens, optimized for looking through thick glass.

--Rik
by rjlittlefield
Sat Oct 17, 2020 1:38 pm
Forum: Equipment Discussions
Topic: Canon DSLR discounts
Replies: 9
Views: 470

Re: Canon DSLR discounts

Thanks for the comment on the 'cancellation' of the AA filter in the 5DS-R - I thought it was removed, not some software attempt to counter it. The cancellation is done optically, sort of a split-and-recombine trick. See https://www.bhphotovideo.com/explora/photography/tips-and-solutions/canon-eos-...
by rjlittlefield
Fri Oct 16, 2020 3:42 pm
Forum: Photography Through the Microscope
Topic: Illumination comparison!
Replies: 4
Views: 284

Re: Illumination comparison!

Interesting images.

Can you tell us more about "Pseudo-DIC" ? My naive guess would be that it's some form of oblique, but more details or a link would be helpful.

--Rik
by rjlittlefield
Wed Oct 14, 2020 2:23 pm
Forum: Macro and Micro Technique and Technical Discussions
Topic: Focus Stacking (using Zerene Stacker)
Replies: 12
Views: 688

Re: Focus Stacking (using Zerene Stacker)

Is slabbing supposed to help ease the pain of halos? I am using ZS Pro (free trial) and in what little chance I've had to actually use it, it seemed I had about as much halo artifact in the slabbed hairy spider that I recently stacked, as the same spider stacked without slabbing. But I am hoping th...
by rjlittlefield
Wed Oct 14, 2020 11:16 am
Forum: Technical and Studio Photography -- Macro and Close-up
Topic: Rare Two Headed California Root Beetle
Replies: 7
Views: 456

Re: Rare Two Headed California Root Beetle

I'm curious, do these make a defensive noise when alive and handled? I ask because up here in the Pacific Northwest we have a similar large beetle that turns out to sound just like a rattlesnake if you annoy it too much. I know this because, decades ago, my mother warned me, and I said oh, OK, and t...
by rjlittlefield
Wed Oct 14, 2020 11:07 am
Forum: Macro and Micro Technique and Technical Discussions
Topic: Focus Stacking (using Zerene Stacker)
Replies: 12
Views: 688

Re: Focus Stacking (using Zerene Stacker)

Could the problem be helped in some circumstances by also taking some pictures of the background without the foreground subject? I was wondering if adding that to the stack might then give the program (and the human who does touching up) information about what to put into the background adjacent to...
by rjlittlefield
Wed Oct 14, 2020 8:37 am
Forum: Equipment Discussions
Topic: Micro-Symmar 3.5x
Replies: 32
Views: 1136

Re: Micro-Symmar 3.5x

In the animation, it seems clear to my eyes that the f/2.8 image is showing finer detail, but the overall contrast is a little lower.

Do you see it differently?

--Rik