Search found 200 matches

by Bob-O-Rama
Thu Jan 19, 2023 12:32 pm
Forum: Technical and Studio Photography -- Macro and Close-up
Topic: Memories... of the RAM I used to have
Replies: 0
Views: 585

Memories... of the RAM I used to have

In terms of chip photography, memory tends to be the most boring in that its just a zillion of the same thing, and often the pattern is so fine it just looks like a sheet of gold leaf. In this sort of botched reflected darkfield at about 3x, you can see there is a lot of structure to it that's not r...
by Bob-O-Rama
Tue Jan 10, 2023 2:23 pm
Forum: Technical and Studio Photography -- Macro and Close-up
Topic: First stack with Finite objective
Replies: 3
Views: 1348

Re: First stack with Finite objective

The lighting thing must be impressive when its powered on. Can you talk a little more about it?

-- Bob
by Bob-O-Rama
Mon Jan 09, 2023 1:34 pm
Forum: Technical and Studio Photography -- Macro and Close-up
Topic: Lichen propagules
Replies: 7
Views: 1362

Re: Lichen propagules

I'm liking your lichens.
by Bob-O-Rama
Thu Jan 05, 2023 7:17 am
Forum: Photography Through the Microscope
Topic: An aster floret cross sections
Replies: 28
Views: 5321

Re: An aster floret cross sections

That's just amazingly beautiful work, and great info on your technique.
by Bob-O-Rama
Wed Jan 04, 2023 10:09 am
Forum: Photography Through the Microscope
Topic: 1980's Fairchild MB4113 Hard Drive Head Preamp
Replies: 0
Views: 653

1980's Fairchild MB4113 Hard Drive Head Preamp

Big chonky hard drives from the 1980's would often have a small integrated circuit mounted on the head actuator arm to do analog to digital conversions, manage head select, write current, and pre-amplification - this reduced the length of analog signal leads to / from the heads, isolating them from ...
by Bob-O-Rama
Tue Jan 03, 2023 2:38 pm
Forum: Technical and Studio Photography -- Macro and Close-up
Topic: An old power transistor
Replies: 2
Views: 716

An old power transistor

I found a few very old power transistors and popped the top off of one to look at the guts. https://photos.smugmug.com/Infinity-Photo-Optical-K2-SC-Long-Distance-Microscope/i-bfcHkD3/0/421643d2/X3/2022-12-31-08.55.49%20ZS%20PMax_Adj-X3.jpg The crop is a bit severe as the minimum magnification of the...
by Bob-O-Rama
Tue Jan 03, 2023 1:38 pm
Forum: Equipment Discussions
Topic: Relationship Between Magnification vs Depth of Field
Replies: 106
Views: 8486

Re: Relationship Between Magnification vs Depth of Field

Bob, the nominal DOF at NA 0.75 is about 0.8 micron if you're pixel-peeping with a critical eye, and about 1.4 micron if you're OK with the classic 0.020 mm blur circle on APS-C. (You can get these numbers easily from the DOF calculator that is built into Zerene Stacker.) My setup uses a WeMacro wi...
by Bob-O-Rama
Tue Jan 03, 2023 12:10 pm
Forum: Technical and Studio Photography -- Macro and Close-up
Topic: Cross Polarized Plastic
Replies: 13
Views: 2297

Re: Cross Polarized Plastic

Those are simply gorgeous!
by Bob-O-Rama
Tue Jan 03, 2023 10:54 am
Forum: Equipment Discussions
Topic: Relationship Between Magnification vs Depth of Field
Replies: 106
Views: 8486

Re: Relationship Between Magnification vs Depth of Field

I actually was going to post a question today about step sizes for high numerical aperture objectives, and if would be worth the effort to trying to get step sizes below 1 micron for a NA=0.75 20x. But after reading all of the foregoing 100 posts I think I'm good. LOL.
by Bob-O-Rama
Thu Dec 15, 2022 12:26 pm
Forum: Photography Through the Microscope
Topic: Diatoms: Epithemia sp. dividing
Replies: 12
Views: 1695

Re: Diatoms: Epithemia sp. dividing

I always wondered how that was managed. Great photo an narrative. I didn't know the subsequent divisions yields smaller and smaller daughters, that's an interesting twist to their life cycle.
by Bob-O-Rama
Wed Dec 14, 2022 3:06 pm
Forum: Photography Through the Microscope
Topic: Christmas Cactus stomata
Replies: 4
Views: 748

Re: Christmas Cactus stomata

Is that the flower petals or the leaves? The flowers themselves are pretty interesting when back lit.
by Bob-O-Rama
Wed Dec 14, 2022 3:00 pm
Forum: Technical and Studio Photography -- Macro and Close-up
Topic: Calla Lily
Replies: 11
Views: 1610

Re: Calla Lily

That could be a total misinterpretstion of what I'm seeing, it just looked sort of familiat from what I have to contend with in microscopy (though obviously not nearly so pronounced) with brighter areas smearing out a bit when they're in best focus. That's what I was thinking, On the second one, th...
by Bob-O-Rama
Wed Dec 14, 2022 2:53 pm
Forum: Technical and Studio Photography -- Macro and Close-up
Topic: Calla Lily
Replies: 11
Views: 1610

Re: Calla Lily

That really nice in every way. You see a lot of "Note everything needs to be stacked!!!" in some of the photo forums, but in this case it really does improve things and lets you express your concept a lot better.

-- Bob
by Bob-O-Rama
Tue Dec 06, 2022 12:57 pm
Forum: Photography Through the Microscope
Topic: Fortress in opal
Replies: 5
Views: 948

Re: Fortress in opal

Its reminiscent of those grow at home crystal kits we had as kids. Its really beautiful.

-- Bob
by Bob-O-Rama
Tue Dec 06, 2022 12:50 pm
Forum: Photography Through the Microscope
Topic: Totally not micrometeorites
Replies: 8
Views: 994

Re: Totally not micrometeorites

Which 20x are you using? A fiber illuminator should be able to pump some light in from the sides even with diffusion but it is tricky with 1mm. Nikon 20x 0.75 NA - I'm using it without cover glass, but compensating somewhat with the tube lens. ( I don't get as good a result with my Mitutoyo 20x ULW...