Search found 7764 matches

by ChrisR
Wed Mar 11, 2020 4:04 pm
Forum: Equipment Discussions
Topic: Building an LED light/flash
Replies: 92
Views: 7575

Gentlemen, the tone of this thread has gone off the rails.
I have deleted most of the ad-hominem comments.

Please let this one cool down.
by ChrisR
Sun Mar 08, 2020 4:44 am
Forum: Equipment Discussions
Topic: Enlarger lenses vs. camera lenses when reversed?
Replies: 8
Views: 1270

Camera lenses have to be "retrofocus" or "inverted telephoto" if the "flange focal distance" (the distance between the flange where the lens attaches and the sensor) isn't long enough. It applies particulalry therefore, to short focal length lenses on SLRs designs where the mirror has to be cleared....
by ChrisR
Sat Mar 07, 2020 4:29 pm
Forum: General Discussion Forum and Community Announcements
Topic: Out of Macrophotography for the Time Being
Replies: 31
Views: 6253

Looks like it was just a couple of car lengths away from you..

Hope you get a place to settle soon. I imagine your landlord will have a list of displaced people to answer, including those who lost everything.

Not fun - keep us informed how it goes?
by ChrisR
Thu Mar 05, 2020 7:46 am
Forum: General Discussion Forum and Community Announcements
Topic: Platinum
Replies: 9
Views: 2255

Smokedaddy wrote:... isn't platinum radioactive?
I think that would be plutonium, Jim ;)
by ChrisR
Tue Mar 03, 2020 6:30 am
Forum: General Discussion Forum and Community Announcements
Topic: Tiny Robots TED Talk
Replies: 6
Views: 1947

I'm not sure how fine the hypodermic needles of which they speak, go. I cadged some from a dentist for dainty things. When I was an undergrad I did a stint at a place in a group which contained the tubeworks Accles and Pollock. The company was set up to make tubes for armamants, bicycle tubing, golf...
by ChrisR
Mon Mar 02, 2020 4:09 am
Forum: Equipment Exchange
Topic: WTB PRINTING NIKKOR 95mm, 105mm or 150mm
Replies: 2
Views: 1235

Very few are in mint condition, they're often pulled from industrial equipment where they get a few marks on the barrel. They seem to be built for it though.
by ChrisR
Sun Mar 01, 2020 6:37 pm
Forum: Equipment Discussions
Topic: Bizarre Nikon Optiphot photo tube attachment ID request
Replies: 12
Views: 993

B would be for a polariser (analyser), surely, but it looks like it may be off something else!
by ChrisR
Sun Mar 01, 2020 6:01 am
Forum: Macro and Micro Technique and Technical Discussions
Topic: Can Zerene's scaling simulate focal length?
Replies: 10
Views: 2459

Steve would the result you're after, come from loading all the frames into photoshop and applying a Transform to each? Then stack with size adjustments turned off. It certainly produces different perspectives. I played with this a while ago with macros, & scripts in different image processors. Sorry...
by ChrisR
Sun Mar 01, 2020 5:31 am
Forum: Equipment Discussions
Topic: I built an on-camera twin LED light rig for stacking
Replies: 2
Views: 891

I'd worry about the strain on the flash mount; particularly if you moved quickly, or had diffusers on the lights.
It could probably be fixed instead to a tripod ring on the lens?
by ChrisR
Tue Feb 25, 2020 6:22 pm
Forum: General Discussion Forum and Community Announcements
Topic: Out of Macrophotography for the Time Being
Replies: 31
Views: 6253

Sheesh, sobering. Glad you're ok - if reeling.
by ChrisR
Tue Feb 25, 2020 6:09 pm
Forum: Photography Through the Microscope
Topic: The Microscopic Beauty of Plants and Trees
Replies: 19
Views: 2815

I've been told Japanese Feather Brand shaving blades are noticeably better than the rest. Whether the "proper " disposable microtome blades are any better than those, I have no idea. This holder holds single or double edged blades or utility knife blades. Do you think it might work for a slider? It ...
by ChrisR
Mon Feb 24, 2020 7:02 pm
Forum: Equipment Discussions
Topic: shared reference silicon wafer for comparisons
Replies: 118
Views: 12205

A generous offer of work!
Count me in for one, please :).
by ChrisR
Mon Feb 24, 2020 2:16 pm
Forum: Administrator's Appreciation Gallery...Macro and Close-up Images
Topic: Different scales
Replies: 6
Views: 3960

Remarkable number of differently coloured scales adjacent and yes, I've not thought of this objective being that good!
by ChrisR
Sun Feb 23, 2020 10:10 am
Forum: Photography Through the Microscope
Topic: The Microscopic Beauty of Plants and Trees
Replies: 19
Views: 2815

@R.B
I have a Reichert-Jung sledge microtome which I'm not sure I'll ever use. Its blades are robust angled things, which would be time-consuming to keep resharpening. Do you know if any of the replaceable blade types are suitable in general for sledges?
by ChrisR
Sun Feb 23, 2020 7:27 am
Forum: Photography Through the Microscope
Topic: The Microscopic Beauty of Plants and Trees
Replies: 19
Views: 2815

Somehow I missed these. This is excellent.

DO look at Robert's article:
https://www.canadiannaturephotographer. ... ants1.html