Search found 2887 matches

by Chris S.
Thu Sep 17, 2009 1:55 pm
Forum: Technical and Studio Photography -- Macro and Close-up
Topic: Medicago polymorpha bur
Replies: 6
Views: 2260

Andrew, the working distance is listed at 11mm. I haven’t directly measured it myself, but that number feels about right. Rik, agreed, a side view of this bur shows something that an end view does not, and vice versa. Under the dissecting scope, I get the impression that there is a central seed, and...
by Chris S.
Thu Sep 17, 2009 1:54 am
Forum: Technical and Studio Photography -- Macro and Close-up
Topic: Medicago polymorpha bur
Replies: 6
Views: 2260

Medicago polymorpha bur

Here is a bur from the Medicago polymorpha plant, known by common names including smooth burclover. A botanist friend of mine collected if from Barry County, Michigan (USA), where it has not previously been reported. His discovery of it there did not especially surprise him, as this Eurasian plant h...
by Chris S.
Sun Sep 13, 2009 1:23 pm
Forum: Equipment Discussions
Topic: Help on positioning equipment
Replies: 44
Views: 7996

Arca-Swiss stuff can get expensive :( (snip) If you, or a friend, has a milling machine, it is quite easy to run up some suitable dovetail plates / bars out of Aluminium I've been buying from an eBay vendor who appears to be doing that very thing. I've bought several pieces from him for my rigs. Hi...
by Chris S.
Wed Sep 09, 2009 5:44 pm
Forum: Technical and Studio Photography -- Macro and Close-up
Topic: Sorus of rock cap fern (Polypodium virginianum)
Replies: 14
Views: 5586

I'm interested to see the difference between a rotation stage and a goniometer. Do you mean the different planes in which the rotation occurs or something more subtle ? Andrew What I'm about to say will make much more sense after I post images, which I can't do now, but will eventually (though it w...
by Chris S.
Tue Sep 08, 2009 1:12 pm
Forum: Technical and Studio Photography -- Macro and Close-up
Topic: Sorus of rock cap fern (Polypodium virginianum)
Replies: 14
Views: 5586

Thanks, everyone, for the compliments, corrections, and discussion. I really appreciate it. Rik and Paul, my goof between Polypodium and Polygonum is embarrassing—a bit like calling an old friend "Anderson" instead of "Henderson." Doh! For both of these genera, I've photographed most of the species ...
by Chris S.
Tue Sep 08, 2009 12:40 am
Forum: Technical and Studio Photography -- Macro and Close-up
Topic: Sorus of rock cap fern (Polypodium virginianum)
Replies: 14
Views: 5586

It must be Polypodium instead of Polygonum :wink: Paul Right you are, Paul--I must be getting tired. After your reply, I edited the orginal post. The sorus is, of course, from a polypodium (as you said) and not a polygonum. I guess it's time for me to catch some shut-eye--shouldn't be making mistak...
by Chris S.
Mon Sep 07, 2009 11:41 pm
Forum: Equipment Discussions
Topic: Time honored discussion :
Replies: 66
Views: 10827

ChrisS - Bruce has a D70S not a D700S, that one isn't produced yet! Oops! Chris R, thanks for catching my typo. After your note, I edited the typo out of the orginal post. Bruce don't despair for "studio" work, for the lack of a mirror lock. Use dim room lighting, a long exposure, say a second, and...
by Chris S.
Mon Sep 07, 2009 10:39 pm
Forum: Technical and Studio Photography -- Macro and Close-up
Topic: Sorus of rock cap fern (Polypodium virginianum)
Replies: 14
Views: 5586

Sorus of rock cap fern (Polypodium virginianum)

First image with my newly-built macro rig. This is the underside of a leaf of the rock cap fern Polypodium virginianum. For those who wonder what we're looking at: You may have noticed that fertile fern leaves have tiny, flat dots on their undersides. Those dots are called "sori" ("sorus" for singul...
by Chris S.
Mon Sep 07, 2009 9:12 pm
Forum: Equipment Discussions
Topic: Time honored discussion :
Replies: 66
Views: 10827

Bruce, It seems we Chris's are thick as thieves at this forum. If you were asking if NikonUser and I are the same person--no, we're not. More likely, you were asking if he is some other Chris. Good luck with your search for a nice second-hand D200. While I don't have any advice about finding a good ...
by Chris S.
Mon Sep 07, 2009 2:49 pm
Forum: Equipment Discussions
Topic: Time honored discussion :
Replies: 66
Views: 10827

Bruce, Marvelous stuff, your underwater work. My experience agrees with others--my D200 and D700 work very nicely on the Nikon PB6 bellows, and on an older off-brand bellows, with no electrical problems. I do need to use a spacer because these bodies would otherwise bump the rear end of the bellows ...
by Chris S.
Mon Jun 15, 2009 11:04 pm
Forum: Equipment Discussions
Topic: Please help identify/mount oddly-threaded Nikon M Plans
Replies: 6
Views: 5414

Apologies for the long overdue reply. I was camping, and splendidly disconnected from computers. Now, back to reality. I had in fact become aware that these objectives had standard RMS threads on adapters--advice from a dealer in used Nikon microscope equipment. I'd even suspected it at first, but t...
by Chris S.
Thu May 21, 2009 10:34 am
Forum: Equipment Discussions
Topic: Bellows rubbish ...
Replies: 35
Views: 9199

I find compressed air to work better than vacuum for this purpose. For my bellows units, I fully extend the bellows to stretch out the folds, then I blow it inside and out using a can of compressed air. I try to aim things down to let gravity help out, but not so much that I tilt the air can and rel...
by Chris S.
Sat May 02, 2009 8:35 am
Forum: Equipment Discussions
Topic: Leads on the Voigtlander 125mm f/2.5 APO (EF mount)?
Replies: 2
Views: 1300

by Chris S.
Fri May 01, 2009 8:14 pm
Forum: Equipment Discussions
Topic: How to repair damaged threads on microscope objective?
Replies: 14
Views: 5818

An afterword for this thread, in case anyone ever has the same issue: I did take the lens to my jeweler friend, who cleaned up the threads in a few minutes and didn't seem to find it difficult. She started with a "watch knife" that I understand is normally used to open watch cases. Pretty soon she w...
by Chris S.
Sat Apr 25, 2009 9:14 am
Forum: Equipment Discussions
Topic: Please help identify/mount oddly-threaded Nikon M Plans
Replies: 6
Views: 5414

The colored band indicates (a range of) magnification. Thanks, Charles. I should have thought about that, but didn't. So the colored bands on these objectives are perfectly consistent with the information on the barrels. The thread on these is the larger "BD" thread. Generally you find the the brig...