Search found 17866 matches

by rjlittlefield
Thu Oct 29, 2020 8:39 am
Forum: Equipment Discussions
Topic: Use of 3D-printer in close-up photography
Replies: 10
Views: 244

Re: Use of 3D-printer in close-up photography

I would like to upload some OpenSCAD files for the mounts I mentioned above. Is there a file upload feature on this forum? In attachments I can only upload certain file types. In general, this forum has disabled uploads of everything except small image files, due to concerns about server capacity a...
by rjlittlefield
Thu Oct 29, 2020 8:25 am
Forum: Macro and Micro Technique and Technical Discussions
Topic: Hand sectioning; plants
Replies: 2
Views: 73

Re: Hand sectioning; plants

Thanks for the post. For future reference, here are direct links to the article: http://www.microscopy-uk.org.uk/mag/artoct20/ms-hand-sectioning-plants.html http://www.microscopy-uk.org.uk/mag/artoct20/ms-hand-sectioning-plants.pdf http://www.microscopy-uk.org.uk/mag/artoct20/ms-hand-sectioning-plan...
by rjlittlefield
Wed Oct 28, 2020 10:02 am
Forum: Photography Through the Microscope
Topic: Diatoms
Replies: 2
Views: 83

Re: Diatoms

Experimenting with graduated backgrounds swapped out in post. Turned out to be quite pleasing. Not sure if doing so falls under the title of "excessive post processing" When in doubt, just say what you did. In a case like this, where somebody says that they're experimenting with a new technique tha...
by rjlittlefield
Tue Oct 27, 2020 8:22 pm
Forum: Photography Through the Microscope
Topic: Porcupine quill
Replies: 8
Views: 149

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: 1114

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: 286

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: 2661

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: 104

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: 589

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: 362

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: 362

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: 511

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: 297

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: 720

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...