Search found 20 matches

by RoxnDox
Fri Oct 13, 2023 12:29 pm
Forum: Technical and Studio Photography -- Macro and Close-up
Topic: Thin-film interference colors on pahoehoe lava
Replies: 10
Views: 2035

Re: Thin-film interference colors on pahoehoe lava

Wow! I love the color and structures from lava glass... Your animation is wonderful and shows it off so beautifully. My own feeble attempts are at much lower magnification ( https://images-wixmp-ed30a86b8c4ca887773594c2.wixmp.com/f/c8eec5eb-5a15-47a9-b568-e9589f922b00/de8wukj-4dde03c3-8991-4914-888b...
by RoxnDox
Sun Nov 20, 2022 6:03 pm
Forum: Macro and Micro Technique and Technical Discussions
Topic: Shooting obsidian - lighting for a barebones setup?
Replies: 10
Views: 2026

Re: Shooting obsidian - lighting for a barebones setup?

Much to peruse and ponder... In a way, my goal is to show off the coloration of this piece, but also to display the smooth curves and the very fine detail in the conchoidal fracture patterns. Might be challenging to get both. I do have a circular polarizer I can experiment with. I can also pursue a ...
by RoxnDox
Sat Nov 19, 2022 11:57 pm
Forum: Macro and Micro Technique and Technical Discussions
Topic: Shooting obsidian - lighting for a barebones setup?
Replies: 10
Views: 2026

Shooting obsidian - lighting for a barebones setup?

Hi folks. Haven't posted here or done much camera work in general for a while - but I just ran into an interesting little issue that got me restarted. I was given a big (according to my wife) pile of obsidian, agate, and other decorative rocks recently. One of my hobbies is (very) amateur flintknapp...
by RoxnDox
Tue May 18, 2021 1:58 pm
Forum: Photography Through the Microscope
Topic: Sticky Marine Diatoms
Replies: 5
Views: 985

Re: Sticky Marine Diatoms

Beautiful little organisms, aren't they? The sand grains are also lovely little rocks, delightful to a geologist's eye!
by RoxnDox
Thu Dec 17, 2020 11:14 am
Forum: Technical and Studio Photography -- Macro and Close-up
Topic: Inclusion in quartz grain
Replies: 2
Views: 2014

Re: Inclusion in quartz grain

Oh, I like those - lovely inclusions. My long-ago mineralogy agrees that rutile is a likely suspect :)
by RoxnDox
Tue Nov 24, 2020 1:20 pm
Forum: Technical and Studio Photography -- Macro and Close-up
Topic: Volcanic Glass
Replies: 8
Views: 3082

Re: Volcanic Glass

Thanks, Leonard. My camera doesn't have the ability to stack frames internally, it's just an entry-level model. I have been shooting manual focus in the sequence you described, starting at the nearest and working toward the furthest. I'm using the manual focus rack to adjust each frame's focus thru ...
by RoxnDox
Mon Nov 23, 2020 4:09 pm
Forum: Technical and Studio Photography -- Macro and Close-up
Topic: Volcanic Glass
Replies: 8
Views: 3082

Re: Volcanic Glass

Very nice; I particularly like the second image in your re-post. Leonard That is one of my favorites as well. It's also a 100% crop from this image: https://images-wixmp-ed30a86b8c4ca887773594c2.wixmp.com/f/c8eec5eb-5a15-47a9-b568-e9589f922b00/de8ws1x-8b6822f6-7868-4c46-89c3-10293b6c2fea.jpg/v1/fil...
by RoxnDox
Mon Nov 23, 2020 4:06 pm
Forum: Technical and Studio Photography -- Macro and Close-up
Topic: Volcanic Glass
Replies: 8
Views: 3082

Re: Volcanic Glass

I did manage a bit more magnification, and a deeper stack today. My wife's camera kit has an old 1.4 TC (late '70s vintage) that I'd forgotten about, so I can get 126mm at the cost of some image quality. This one is a 15 frame stack, but it looks like I pushed Focus Stacker past its limits in the co...
by RoxnDox
Sun Nov 22, 2020 9:12 pm
Forum: Technical and Studio Photography -- Macro and Close-up
Topic: Volcanic Glass
Replies: 8
Views: 3082

Re: Volcanic Glass

Very nice subject and image. I wonder if you could be able to show a deeper stack, a stereo pair also would be most enjoyable Thank you :) If I can find that particular spot again (that bit took some damage) I can try for a deeper stack. At this stage in my (very beginning) skill level I would have...
by RoxnDox
Thu Nov 19, 2020 9:13 pm
Forum: Technical and Studio Photography -- Macro and Close-up
Topic: Volcanic Glass
Replies: 8
Views: 3082

Volcanic Glass

Another of my lava samples from the 2018 Kilauea eruption. This time it was seeing what I could get with a piece of tephra - the very light, very fragile ejecta that is shot up in the air from the lava fountains, cools very rapidly, and falls like ash everywhere in the area. It's so light because th...
by RoxnDox
Thu Nov 19, 2020 9:00 pm
Forum: Technical and Studio Photography -- Macro and Close-up
Topic: Floppy-ear Bunnies
Replies: 7
Views: 3605

Re: Floppy-ear Bunnies

Looks like some serious cross-species stuff was kickin' it up between the bunnies and the buggies! Those are some odd looking critters indeed.

But I really like the image!
by RoxnDox
Fri Oct 23, 2020 9:37 pm
Forum: Technical and Studio Photography -- Macro and Close-up
Topic: Fluorite with masking tape
Replies: 12
Views: 5700

Re: Fluorite with masking tape

VERY cool images and mineralogy!
by RoxnDox
Fri Oct 23, 2020 9:34 pm
Forum: Technical and Studio Photography -- Macro and Close-up
Topic: Lovely Lava
Replies: 0
Views: 3027

Lovely Lava

A view of some lovely frothy, almost pumice-y, basaltic lava from Kilauea's Lower East Rift Zone 2018 eruption. This is a stack of four frames (Focus Stacker on my Mac). Pentax K-50 w/ Tamron 90mm Macro, LED lighting in a tabletop lightbox. Four x f/8, ISO 100 https://images-wixmp-ed30a86b8c4ca88777...
by RoxnDox
Fri Jun 12, 2020 11:38 pm
Forum: Technical and Studio Photography -- Macro and Close-up
Topic: Cubic pyrite crystals
Replies: 1
Views: 1924

Cubic pyrite crystals

Worked with a fist-sized mass of crystalline pyrite today. Sat it on a fence rail out on the deck, natural shaded light. Tripod and focus rail, Pentax K-50 w/ Tamron SP Di 90mm Macro. Images stacked on the Mac using Focus Stacker and a bit of editing in Gimp. Hopefully the links won't be a problem t...
by RoxnDox
Tue Jun 09, 2020 1:25 pm
Forum: Technical and Studio Photography -- Macro and Close-up
Topic: Turbidite microstructures
Replies: 2
Views: 1501

Thank you. I agree, the URLs from that site are horrible. They made changes a while back and now we are stuck with that vs a decently short address. I did try a couple of times to get it right here, using the preview function, but could't get it. After submitting, I finally had to go back, resave th...