Search found 19092 matches

by rjlittlefield
Sat Oct 01, 2022 9:34 pm
Forum: Macro and Micro Technique and Technical Discussions
Topic: Quirks of Canon R7 full electronic shutter
Replies: 1
Views: 24

Quirks of Canon R7 full electronic shutter

SUMMARY Using full electronic shutter, my Canon R7 camera shows up to 130 milliseconds variation in lag time between cabled remote shutter pulse and start of exposure. The pattern of this delay varies strongly depending on circumstances. In some situations the delay varies almost uniformly across t...
by rjlittlefield
Sat Oct 01, 2022 5:52 pm
Forum: Photography Through the Microscope
Topic: Anemia
Replies: 3
Views: 146

Re: Anemia

iconoclastica wrote:
Wed Sep 28, 2022 1:35 pm
Wouldn't it be possible to edit the depthmap and rerun the stack with it?
I think I am not understanding the idea.

In principle one could re-render the stack given an edited depthmap.

But then how would the depthmap get edited, without doing something equivalent to manual retouching?

--Rik
by rjlittlefield
Sat Oct 01, 2022 5:42 pm
Forum: Administrator's Appreciation Gallery...Photography Through the Microscope
Topic: Drosophila melanogaster, recently eclosed adult (Stephen_De_Lisle)
Replies: 0
Views: 11

Drosophila melanogaster, recently eclosed adult (Stephen_De_Lisle)

The following image represents the winning thread for the October 2022 award for Micro. It was originally posted at https://www.photomacrography.net/forum/viewtopic.php?t=45095 . We're reproducing the image here, separately, as part of our procedure to provide clarity when the front page shows one i...
by rjlittlefield
Sat Oct 01, 2022 3:30 pm
Forum: Photography Through the Microscope
Topic: Administrators Appreciation Award Winners for October 2022
Replies: 0
Views: 11

Administrators Appreciation Award Winners for October 2022

We are pleased to announce this month's winners of the Administrators Appreciation Awards! :D In the Photomacrography Forums, we honor David Yager (dy5) for his mantis deimatic display, the image at https://www.photomacrography.net/forum/viewtopic.php?t=45200 . In the Photomicrography Forum, we hono...
by rjlittlefield
Sat Oct 01, 2022 3:28 pm
Forum: Technical and Studio Photography -- Macro and Close-up
Topic: Administrators Appreciation Award Winners for October 2022
Replies: 0
Views: 17

Administrators Appreciation Award Winners for October 2022

We are pleased to announce this month's winners of the Administrators Appreciation Awards! :D In the Photomacrography Forums, we honor David Yager (dy5) for his mantis deimatic display, the image at https://www.photomacrography.net/forum/viewtopic.php?t=45200 . In the Photomicrography Forum, we hono...
by rjlittlefield
Sat Oct 01, 2022 3:26 pm
Forum: Nature Photography -- Macro and Close-up
Topic: Administrators Appreciation Award Winners for October 2022
Replies: 0
Views: 21

Administrators Appreciation Award Winners for October 2022

We are pleased to announce this month's winners of the Administrators Appreciation Awards! :D In the Photomacrography Forums, we honor David Yager (dy5) for his mantis deimatic display, the image at https://www.photomacrography.net/forum/viewtopic.php?t=45200 . In the Photomicrography Forum, we hono...
by rjlittlefield
Thu Sep 29, 2022 3:08 pm
Forum: Beginners Macro
Topic: 5x with a budget rail and tripod?
Replies: 10
Views: 272

Re: 5x with a budget rail and tripod?

The equation I found on this forum: NA = M / square root (4 f squared (M+1)squared + M squared) This appears to be the exact formula for a thin lens approximation, where f = focal length / aperture diameter, that is, the lens's f-number not corrected for magnification. ... --Rik Thanks for the sour...
by rjlittlefield
Wed Sep 28, 2022 10:44 am
Forum: General Discussion Forum and Community Announcements
Topic: RIP Nick Gray (gardenersassistant)
Replies: 2
Views: 112

RIP Nick Gray (gardenersassistant)

I am saddened to report the death of Nick Gray (gardenersassistant). Nick has has been a valued member of this and other photo communities for many years. His presence and contributions will be missed. https://www.northsomersettimes.co.uk/memorials/death-notices/death/30486056.nicholas-robin-gray/ T...
by rjlittlefield
Wed Sep 28, 2022 9:51 am
Forum: Beginners Macro
Topic: 5x with a budget rail and tripod?
Replies: 10
Views: 272

Re: 5x with a budget rail and tripod?

I'm somewhat worried though that the resolution improvements that can be obtained with a 0.10 NA objective would be somewhat underwhelming when compared to my current 2x lens. ... When using NA = M / sqrt(4*f^2 *(M+1)^2 + M ^2) with M=2 and f=4 to estimate the NA, I find an NA of 0.083 which is pre...
by rjlittlefield
Wed Sep 28, 2022 9:30 am
Forum: Photography Through the Microscope
Topic: Anemia
Replies: 3
Views: 146

Re: Anemia

In general, I couldn't find dMap settings that worked well. There was quite a lot of contrast from the deeper layers brought to the front, often in the form of irregular concentric rings. It was like there was not enough information in the originals to give the stacking process the foothold it need...
by rjlittlefield
Sun Sep 18, 2022 8:27 pm
Forum: Equipment Discussions
Topic: lighting cage with CAMVATE clamps and arms
Replies: 32
Views: 2260

Re: lighting cage with CAMVATE clamps and arms

If you do need an arm for precise positioning, you should not use arms that have matching rosettes to lock the arm's "elbow". These rosettes ensure that there is no slippage, but force the arm to be locked at discrete positions (usually every 2° or 4° angles, or multiples thereof). The elbow cannot...
by rjlittlefield
Sun Sep 18, 2022 12:36 pm
Forum: Technical and Studio Photography -- Macro and Close-up
Topic: Tracheae and spiracles of grape leaffolder caterpillar
Replies: 10
Views: 391

Re: Tracheae and spiracles of grape leaffolder caterpillar

For context, here is a 5X view of the entire cross-section. The spiracle being imaged is at the left side, just above center. https://janrik.net/MiscSubj/2022/GrapeLeafRoller_2022/IMG_6089.jpg This is a single frame, not cropped. At this web-sized scale the entire depth of the spiracle fits comforta...
by rjlittlefield
Sat Sep 17, 2022 6:00 pm
Forum: Technical and Studio Photography -- Macro and Close-up
Topic: Tracheae and spiracles of grape leaffolder caterpillar
Replies: 10
Views: 391

Re: Tracheae and spiracles of grape leaffolder caterpillar

Here is the overall setup for the preceding shot. Illumination is very simple, just a single flash unit sitting a few inches behind a piece of thick vellum tracing paper. I figured that with the structure and orientation of this subject, there was only one path for light to get into the spiracle any...
by rjlittlefield
Sat Sep 17, 2022 5:18 pm
Forum: Technical and Studio Photography -- Macro and Close-up
Topic: Tracheae and spiracles of grape leaffolder caterpillar
Replies: 10
Views: 391

Re: Tracheae and spiracles of grape leaffolder caterpillar

Everyone, thank you for the kind words. This has been a very challenging subject, which has somehow gotten its hooks into me so that it's difficult to let go. I tried again at higher resolution. The technique was to prepare a dry whole specimen by dehydrating in acetone and washing in HMDS before ai...
by rjlittlefield
Sat Sep 17, 2022 4:34 pm
Forum: Beginners Micro
Topic: Software question
Replies: 7
Views: 236

Re: Software question

Please note also there are a couple of new answers in your original thread, at https://www.photomacrography.net/forum/ ... 47#p284347 .

--Rik