Search found 191 matches

by JW
Mon Aug 02, 2021 8:13 am
Forum: Equipment Discussions
Topic: 42 or 58 diameter tubes
Replies: 8
Views: 161

Re: 42 or 58 diameter tubes

Rik, Chris - unfortunately my 58 mm extension tubes are not threaded, they have Canon EF compatible mounts - seemed like a good idea at the time. The configuration is about 120mm of these tubes attached to the camera's lens mount, followed by a reverse 150 Raynox, then either a 10x or 20x objective ...
by JW
Sun Aug 01, 2021 6:26 pm
Forum: Technical and Studio Photography -- Macro and Close-up
Topic: Ludwigite accidental panoramic
Replies: 0
Views: 32

Ludwigite accidental panoramic

Hunting through a specimen of skarn marble rock from eastern Fresno County, California, I wanted to get images of the clear chondrodite crystals in the white calcite marble, and found one area that featured a nice black ludwigite crystal. After composing some other images, came across a similar situ...
by JW
Sun Aug 01, 2021 6:16 pm
Forum: Equipment Discussions
Topic: 20X Objective Quest
Replies: 9
Views: 329

Re: 20X Objective Quest

Yikes! I'll take a close look at the lens under the microscope, maybe I'll see something...

thanks for the tip, Scarodactyl
by JW
Sun Aug 01, 2021 5:01 pm
Forum: Equipment Discussions
Topic: 42 or 58 diameter tubes
Replies: 8
Views: 161

Re: 42 or 58 diameter tubes

Thanks for the comments! If I wasn't clear, I currently am using 58 mm tubes, which are strong but not stiff, these things seem to wave in the breeze. Since I couldn't find a commercial solution to clamping them down, I thought about going to 42 mm. I am going to get a 200 mm Arca-compatible lens pl...
by JW
Sun Aug 01, 2021 4:55 pm
Forum: Equipment Discussions
Topic: 20X Objective Quest
Replies: 9
Views: 329

Re: 20X Objective Quest

Again, thanks everyone for the comments. I did indeed end up getting the Mitutoyo 20x with the horrible barrel damage. Wasn't as bad as the posted images, and there does not seem to be anything wrong with the objective. Test images show nearly no CA of any type. However, there is a noticeable color ...
by JW
Sat Jul 31, 2021 5:45 pm
Forum: Equipment Discussions
Topic: 42 or 58 diameter tubes
Replies: 8
Views: 161

42 or 58 diameter tubes

For some time 42 has been the answer to the 'ultimate question', but why not 58mm instead? When using 10X or 20x infinite focus objectives, with the usual reversed Raynox 150mm, does tube diameter matter? I would guess that the larger diameter may help to reduce reflections, etc., but could be wrong...
by JW
Tue Jul 20, 2021 5:35 pm
Forum: Equipment Discussions
Topic: 20X Objective Quest
Replies: 9
Views: 329

Re: 20X Objective Quest

Thank you - appreciate the answers. Axial CA is bad for the minerals and crystals that I photograph, so I'll go with the Mitutoyo, if its bad the seller has a return policy
by JW
Tue Jul 20, 2021 3:00 pm
Forum: Macro and Micro Technique and Technical Discussions
Topic: DMap intermediate output - ZS
Replies: 3
Views: 164

Re: DMap intermediate output - ZS

Fantastic, thanks Rik!
by JW
Tue Jul 20, 2021 12:56 pm
Forum: Macro and Micro Technique and Technical Discussions
Topic: DMap intermediate output - ZS
Replies: 3
Views: 164

DMap intermediate output - ZS

We are all familiar with the need to set DMap Contrast threshold manually about 50% through the process. Rarely (OK, occasionally) I pick the wrong value and the final image looks like crap. Is there a way to go back to the 'set contrast threshold' slider without having to start the stacking process...
by JW
Tue Jul 20, 2021 12:53 pm
Forum: Equipment Discussions
Topic: 20X Objective Quest
Replies: 9
Views: 329

20X Objective Quest

So far I've had two orders for a Mity 20x objective cancelled and refunded in the past month, after receiving confirmation of order and payment :? I've a lead on two additional objective lenses, on is another Mity 20x, but with significant superficial? damage (appears as if a gorilla took a pipe wre...
by JW
Thu Jul 15, 2021 10:31 am
Forum: Equipment Discussions
Topic: Mity 20x NUV usability?
Replies: 3
Views: 100

Re: Mity 20x NUV usability?

Thank you Scarodactyl, that's what I wanted to know.
by JW
Thu Jul 15, 2021 10:21 am
Forum: Equipment Discussions
Topic: Mity 20x NUV usability?
Replies: 3
Views: 100

Mity 20x NUV usability?

This purple guy is for sale on e-bay, the seller has five of them : Mitutoyo Objective Lens M Plan Apo NUV 20x /0.40 ∞/0 f=200 I don't need the near UV correction - but, will this work just as well as a 'normal' 20x for stacking, the working distance is given as 17 mm, which should be fine for my pu...
by JW
Tue Jun 22, 2021 8:13 am
Forum: Macro and Micro Technique and Technical Discussions
Topic: Aligning images - widely varying illumination types
Replies: 2
Views: 168

Re: Aligning images - widely varying illumination types

Rik - that's what I figured when ZS does alignment, very much appreciate the example. Back in the day I used a simple JavaScript snippet to effect a mouse-over to swap images. Also, I should have been more clear - the two images posted above were single shots from the middle of each stack. I haven't...
by JW
Mon Jun 21, 2021 7:59 pm
Forum: Macro and Micro Technique and Technical Discussions
Topic: Aligning images - widely varying illumination types
Replies: 2
Views: 168

Aligning images - widely varying illumination types

So, I took two stacks of the same subject, at 5X. First pass was with a UV-LW lamp, the second was with flash. Each stack is 22 images and each requires alignment. Ultimately, after processing each separately, they will be presented as fluorescent overlay over visible, so the user can slide or switc...
by JW
Fri Jun 11, 2021 8:57 pm
Forum: Technical and Studio Photography -- Macro and Close-up
Topic: Mayfly molting from subimago to adult
Replies: 11
Views: 313

Re: Mayfly molting from subimago to adult

Rik - it looks to me that the claws of the old skin legs are not moving - perhaps these are dug in or stuck to the table with enough adhesion to enable the fly to push itself out?