Search found 18032 matches

by rjlittlefield
Mon Feb 15, 2021 9:36 pm
Forum: Macro and Micro Technique and Technical Discussions
Topic: Focus stacking algorithms: Zerene vs Photoshop
Replies: 9
Views: 895

Re: Focus stacking algorithms: Zerene vs Photoshop

Rik, could you give a little suggest to spot better the differences ? I don't have much to add, beyond what you've written. I am glad to see "simplified base idea" in the description of contrast weighting. There are a lot of possibilities at that stage, notably using weighting functions that are no...
by rjlittlefield
Sun Feb 14, 2021 7:34 pm
Forum: Beginners Macro
Topic: Compare macro results from 2 different enlarger lenses.
Replies: 6
Views: 176

Re: Compare macro results from 2 different enlarger lenses.

Welcome to the forum! These test shots look fine for sharpness. Both lenses have good reputations and both appear to be in good condition. I see no trace of motion blur. At effective f/25 on 43 megapixel fullframe, you are stopped down as far as you possibly can be, without losing detail to diffract...
by rjlittlefield
Fri Feb 12, 2021 5:35 pm
Forum: Technical and Studio Photography -- Macro and Close-up
Topic: Nice stone
Replies: 5
Views: 349

Re: Nice stone

The color balance and contrast of the second image are much different from the first. The second image looks very dark and washed out. If your camera provides manual control over exposure and color balance, then I suggest to set those from a gray card at the subject's position, with the plastic plat...
by rjlittlefield
Fri Feb 12, 2021 11:22 am
Forum: Photography Through the Microscope
Topic: Chondritic Meteorite section
Replies: 9
Views: 393

Re: Chondritic Meteorite section

Very nice! The original image is 50,000 x 30,000px Thinking of this image in terms of a print, those dimensions translate to 13.9 x 8.3 feet, at 300 pixels per inch. So, as custom wallpaper, that would fill a good-sized "feature wall" at a resolution that would look tack sharp standing close with re...
by rjlittlefield
Sun Feb 07, 2021 7:24 pm
Forum: Photography Through the Microscope
Topic: Embossed escutcheons on revenue stamps from the 18th and 19th Century
Replies: 30
Views: 1084

Re: Embossed escutcheons on revenue stamps from the 18th and 19th Century

More great info and images -- keep 'em coming!

For me the inverted stamp was momentarily concave, but it popped convex within a couple of seconds and now it is stubbornly stuck there, with the light coming from the bottom.

--Rik
by rjlittlefield
Sun Feb 07, 2021 5:32 pm
Forum: Community Members and Friends
Topic: Hello from Ontario
Replies: 2
Views: 199

Re: Hello from Ontario

Fred, welcome aboard! That's an excellent snowflake image.

I watched a bit of one hockey video. If your grandsons can hang with those guys, they skate waaay better than I ever could.

--Rik
by rjlittlefield
Sat Feb 06, 2021 12:27 pm
Forum: Photography Through the Microscope
Topic: Pyrrosia lanceolata
Replies: 4
Views: 306

Re: Pyrrosia lanceolata

Same subject, same microscope, but now with polarizers in place. Isn't it remarkeble how much less details are visible? That's a dramatic comparison. If the polarizers are crossed, then I expect what we've lost is all the one-bounce specular reflections/refractions from the surface of the subject, ...
by rjlittlefield
Fri Feb 05, 2021 10:32 pm
Forum: Technical and Studio Photography -- Macro and Close-up
Topic: Cicada ovipositor
Replies: 10
Views: 512

Re: Cicada ovipositor

That looks exactly like the mechanism used by bee & wasp stingers to penetrate hide. It may be the same anatomy, just tweaked a little.

--Rik
by rjlittlefield
Fri Feb 05, 2021 12:49 pm
Forum: Macro and Micro Technique and Technical Discussions
Topic: Focus stacking algorithms: Zerene vs Photoshop
Replies: 9
Views: 895

Re: Focus stacking algorithms: Zerene vs Photoshop

No need to know the algorithms. Just stack the same image with Zerene and Photoshop. I'll guarantee the Zerene image will have fewer artifacts :D Maybe Rik will explain this - I have better luck with PS stacking transparent crystals. Simple -- I disagree with elf. What I would guarantee is that PS ...
by rjlittlefield
Thu Feb 04, 2021 10:44 am
Forum: Photography Through the Microscope
Topic: Embossed escutcheons on revenue stamps from the 18th and 19th Century
Replies: 30
Views: 1084

Re: Embossed escutcheons on revenue stamps from the 18th and 19th Century

What a rich subject!

For me, the inverted one appeared concave for a moment, then it snapped to convex and now stubbornly stays there.

--Rik
by rjlittlefield
Thu Feb 04, 2021 10:36 am
Forum: Equipment Discussions
Topic: My setup - need some lighting advice
Replies: 18
Views: 958

Re: My setup - need some lighting advice

Troels, good catch!

The Jansjö lamps that I use are the old ones that are AC powered. I have no experience with the USB versions.

--Rik
by rjlittlefield
Tue Feb 02, 2021 8:39 pm
Forum: Equipment Discussions
Topic: My setup - need some lighting advice
Replies: 18
Views: 958

Re: My setup - need some lighting advice

JSkory wrote:
Tue Feb 02, 2021 6:45 pm
So when you said you had to use cross polarization to cut down on reflection did you use a filter in front of the light?
Yes. There's a photo of the setup shown later in the thread, at viewtopic.php?p=234913#p234913 .

--Rik
by rjlittlefield
Tue Feb 02, 2021 6:26 pm
Forum: Photography Through the Microscope
Topic: Embossed escutcheons on revenue stamps from the 18th and 19th Century
Replies: 30
Views: 1084

Re: Embossed escutcheons on revenue stamps from the 18th and 19th Century

So, a day later, I am now stuck in the "correct" perception. Try as I might, I cannot consciously flip between convex/concave by imagining different illumination. Instead my perception remains stuck in convex, with the inferred angle for illumination forced to either top or bottom to match the subje...
by rjlittlefield
Tue Feb 02, 2021 6:14 pm
Forum: Equipment Discussions
Topic: My setup - need some lighting advice
Replies: 18
Views: 958

Re: My setup - need some lighting advice

Why are the Janso lights so popular with you guys? Do you use them for something other than main lighting? I often use Jansjö lights for main illumination, usually with paper for diffusion and usually with custom color balance off a white card. The ones that I have are not terribly far off my camer...
by rjlittlefield
Mon Feb 01, 2021 10:04 pm
Forum: Administrator's Appreciation Gallery...Macro and Close-up Images
Topic: Mating gaudy grasshoppers (by hayath)
Replies: 0
Views: 429

Mating gaudy grasshoppers (by hayath)

The following image represents the winning thread for the February 2021 award for Macro. It was originally posted at https://www.photomacrography.net/forum/viewtopic.php?t=42939 (image #1 of that thread). We're reproducing the image here, separately, as part of our procedure to provide clarity when ...