The last click beetle trigger photos?

rjlittlefield · Post by **rjlittlefield** » Tue Jun 13, 2006 11:03 pm

Probably not!

Sorry if I seem to be overworking this subject, but I'm having great fun looking at this structure in detail for the first time ever.

Here's the other half of the trigger mechanism. This is the "underside" of the famous spine that slips into the slot. It's actually the dorsal side of the spine, but since the clicks happen mostly when the beetle is on its back, it operates mostly "this side down".

Looking more closely...

And finally a composite of both parts of the trigger -- sort of an "exploded view". In operation, the two parts lock together at the ridges that are marked.

Technical data same as for the first post, Edmund 20X NA 0.40 microscope objective, direct projection onto sensor of Canon Digital Rebel, stacked at 0.0002" (5 microns) using Helicon Focus.

Hope you're enjoying these as much as I am! When I first tried this lens, I didn't think it was going to be much use for stacking. Sometimes it's nice to be wrong.

--Rik

Edited to add, 4/28/2023: old journal papers describing the operation of this mechanism can be found at https://janrik.net/Papers/ClickBeetlePaper1.pdf and
https://janrik.net/Papers/ClickBeetlePaper2.pdf .

Ken Ramos · Post by **Ken Ramos** » Wed Jun 14, 2006 2:45 am

Some terrific shots here Rik.

I have a set of Edmund objectives, I may try duplicating your set up someday soon.

Charles Krebs · Post by **Charles Krebs** » Thu Jun 15, 2006 3:02 pm

Extremely well done Rik. Very unique and interesting.

rjlittlefield · Post by **rjlittlefield** » Thu Jun 15, 2006 10:42 pm

Charlie, thanks for the compliment. Being able to produce images like this is a real treat, and I owe a lot of it to cribbing off your techniques. Thanks for sharing!

Ken, have it at -- there's no magic, just a lot of mistakes under the bridge. The mantra here is KISS -- Keep It Stable, STABLE! I don't think I mentioned exposure time on these pics. It's about 1 second per frame, with mirror lockup. I turn down the brightness on the fiber illuminator to get that long of an exposure. With a shorter exposure time of say 1/30 second, I still get unacceptable shake just from shutter movement. The longer exposure gives enough time for that vibration to die out, so that most of the exposure is during stable time. I also throw out the cats, threaten the family, and sit real still while pressing the button on the remote shutter release.

--Rik

Mike · Post by **Mike** » Fri Jun 16, 2006 4:25 am

Rik,

I sure hope these aren't the last!

Really an excellent treatise on the mechanism they use and the photos are superb.

In one way I wish you hadn't done this as now I have ANOTHER project I really want to try.

Thanks for providing all the information and photos of your system - I've printed them out and will use for reference.

All the best,
Mike

Wim van Egmond · Post by **Wim van Egmond** » Wed Jun 21, 2006 2:51 am

That is fascinating, Rik!!! It has always puzzled me.

I am not sure if you are interested but perhaps you'll like this?
http://www.microscopy-uk.org.uk/mag/artdec05/click.html

By the way, I have been travelling a lot so I have been quiet for weeks:-)

Wim

rjlittlefield · Post by **rjlittlefield** » Wed Jun 21, 2006 8:31 pm

Mike, thanks! Not to worry, I was just joking about "last". But it may be a while -- it's hard to squeeze this stuff in around work and chores.

Wim, hi! I figured you were off doing other things for a while but would be back eventually.

I saw your page a few weeks ago. Lovely photomicrographs!

Did you look at the movies linked in my post at http://www.photomacrography1.net/forum/ ... php?t=5101? I think they capture the action fairly well, which should answer one of your questions.

I was not able to find much on the web about details of the mechanism. Everybody pretty much stops at "there's a spine and a groove, and that makes the click".

But I tracked down a click beetle specialist and asked about references on the mechanism. It turns out that there are two papers published way back in 1972 and 1973 that are supposed to go over this in great detail. I have ordered them through my local library, but it may take a few weeks for somebody somewhere to pull them out of the old journal stacks and run them through a copier. When I get a chance to read them, I'll let you know what catches my attention.

Thanks for the interest, guys!

--Rik

Wim van Egmond · Post by **Wim van Egmond** » Thu Jun 22, 2006 3:15 am

Thanks Rik,

Unfortunately I could not open the WMV files on my Mac computer. So the answer will always be a mystery to me!

Wim

rjlittlefield · Post by **rjlittlefield** » Thu Jun 22, 2006 8:28 am

Wim, sorry about that. I didn't think about wmv's not being readable by Mac's.

Try this DivX-encoded .avi instead. If you don't have the DivX codec, it's a free download at http://www.divx.com/divx/mac/.

Let me know what happens, please. I don't have a Mac handy to test with.

--Rik

Wim van Egmond · Post by **Wim van Egmond** » Sat Jun 24, 2006 2:43 am

Hello Rik,

That one worked! Thank you. It is a great video which gives me teh answer I was looking for when I wrote my little article!

I have an application for WMV's but sometimes they don't work.

all the best,

Wim

rjlittlefield · Post by **rjlittlefield** » Thu Aug 24, 2006 9:44 am

It's a bit of an afterthought, but perhaps people interested in stacking may want to see this comparison of a single frame versus the extended-depth-of-field composite. This is a fairly deep stack at wide aperture (66 frames, NA 0.4), so the effect is striking.

--Rik