3D Stereo Photomacrography - Photomicroscopy

John,
Your input was appreciated.

Now a digression....
After dinner last night I was rummaging through some images that I had 'saved' off the web a couple of years back.
There was a wonderful photomacrograph of a collision between water droplets, as shown here:
  Link : http://www.kscitech.com/MicGroup/Temp/Pic_JH.htm

It was labeled JH_02 and it may well be your work. Can you confirm this?
Also, is there a webpage someplace describing the technique?

Thanks, Keith

"John Hart" wrote:
>> You'd get RAW format (16 bits per color), and higher dynamic range.
>> So the 16-bit color value is for each of the [R,G,G,B] data components of a
>> Bayer filter array? That is, you get to play your own de-mosaicing games...
> I think in principle yes (for some cameras). I have only used
> canned converters (which do the above) in photoshop, phase one,
> and helicon filter, leading to a .tif file (16 bit per RGB color)
> that you can further adjust in the more standard ways.

"scitech200" wrote:
> It was labeled JH_02 and it may well be your work.

Yes that's mine. For more pix and info please see:
  Link : http://www.stereo3dgallery.net/

These are stereo macro shots, so if you can view 3D cross-eyed, parallel (wide-eyed), anaglyph (not so good), etc., you can get the real deal.

My main interest these days is 3D extreme-macro and microscopy, which is why I check into this group on occasion.

Thanks, John

[ John's dual-camera macro rig, as shown here, is described on his website ]

John,
Thank you for confirmation on your great image - my filing system was pretty loose up until very recently, when the Archive website work dictated otherwise.

I have updated the webpage: http://kscitech.com/MicGroup/Temp/Pic_JH.htm (see link above) as there was a lot of interest from group members last night.

You wrote:
> These are stereo macro shots, so if you can view 3D cross-eyed, parallel (wide-eyed),
> anaglyph (not so good), etc., you can get the real deal.

So your beam-splitting technique for obtaining 3D stereo images is distinctly different from that used by David Sykes, for example, which requires viewing of two side-by-side images?
Now I'm not adept at cross-eyed viewing, but it's intriquing that all information for 3D viewing is contained in a single image.

At the risk of digressing too far from microscope topics, we would appreciate your additional comments.

I have tried some simple macro photos of a falling water droplet and less than 1 in 100 were of any real interest. Out of curiosity, photo by photo, what are the chances of capturing a collision as depicted in your spectacular image?

Regards, Keith

"scitech200" wrote:
> I have updated the introductory webpage: http://kscitech.com/MicGroup/Temp/ Pic_JH.htm
> as there was a lot of interest from group members last night.

That's nice. I hope some could see the 3D versions at www.stereo3dgallery.net (under John Hart's exhibits dated Nov 2006)

> So your beam-splitting technique for obtaining 3D stereo images is
> distinctly different from that used by David Sykes, for example,
> which requires viewing of two side-by-side images?

I don't know what David is using for macros these days, but the beamsplitter is just a way to allow two cameras to take respective left and right views with a closer horizontal separation between the lenses than could be obtained by placing the relatively large cameras side by side.

> Now I'm not adept at cross-eyed viewing, but it's intriquing that
> all information for 3D viewing is contained in a single image.

Viewing has always been the weak aspect of 3D. Side by side (crossed or normal) is one way, but there are many others (shutterglasses, polarized beamsplitter with two monitors, single mirror with two images/monitors, color encoded 3D's, etc.). Some methods, like the latter, involve looking at a single image. So does looking at a spatially multiplexed polarized LCD panel or a parallax barrier or lenticular LCD screen. In all cases, at least two images, L and R, are generally used as source material.

Many people need some aid to view 3D on a computer screen (I too find cross-eyed viewing difficult). One simple and popular aid is the Pokescope (www.pokescope.com). A cosmetic mirror can be used too, in a pinch (see the viewing techniques section of www.stereo3dgallery.net ).

Sorry for the long digression. But 3D is very cool (I had almost 300 people show up at a local climbing club for a 3D canyoning show last week - expected about 50), and very little has been done in high-quality 3D imaging using light microscopes, so members of this qroup might be interested. There are some polarized light 3D microscopy of crystals at:
  Link : www.stereo3dgallery.net

> ...I have tried some simple macro photos of a falling water droplet and less than
> 1 in 100 were of any real interest.....

Temperature changes, dust, almost-invisible surface ripples, etc., can affect the results. The very last one at www.stereo3dgallery.net, where 3 drops simultaneously explode was a 1 in 100 gig, even with a very carefully constructed drop dispenser. Single drops were more like 1 in 3 for interesting shots, but you need a beam-interupt digital delay line to light up events that last only a few milliseconds with a critically timed flash.

John

John,
I have to apologize - now things make more sense, once I took the time to access the 3D stereo pairs! Sometimes, in early morning, another cup of coffee is in order before posting...

I trust that this webpage update: http://kscitech.com/MicGroup/Temp/Pic_JH.htm (see link above) is acceptable to you for clarification of the 2D and 3D options.

Thanks again for all of your comments.

Regards, Keith

"John Hart" wrote:
> I don't know what David is using for macros these days

All sorts of things ... including a stereo microscope rig for stereo movies of subjects 75mm wide and smaller.
I guess it is Spring in the Northern hemisphere so time to start testing it.

> beamsplitter is just a way to allow two cameras to take respective
> left and right views with a closer horizontal separation

I would use the same method, with a camera separation of 1/15th subject distance (but that is a discussion for elsewhere !).

> A cosmetic mirror can be used too

You know there is a better method, tell the people :-)

> There are some polarized light 3D microscopy of crystals at:
> www.stereo3dgallery.net/cgi_bin/gallery/view.cgi? username=jhart&catid=2

I was looking at those last week. No details of the method it took five years to devise but I have just built something using three stepper motors so maybe I have the main components ?

> but you need a beam-interupt digital delay line to light up events
> that last only a few milliseconds with a critically timed flash.

After making this post, and another cup of tea, I am going to learn how to programme the microcontroller I recently bought.

My first project will be to replicate the functions of a device which I think you used (at least initially) for those droplet images :-
http://www.bmumford.com/photo/camctlr.html
http://www.bmumford.com/photo/highspeed/index.html

This morning, I finished making one of these, for a fraction of the cost :-
http://www.bmumford.com/photo/rotary/index.html
I just need to programme a microcontroller to move the camera in two degree steps and perform other functions.

So little time :-)
David

"David Sykes" wrote:
> This morning, I finished making one of these, for a fraction of the
> cost :- http://www.bmumford.com/photo/rotary/index.html
> I just need to programme a microcontroller to move the camera in two
> degree steps and perform other functions.

David,
Your last line says it all!!! Mumford's devices aren't all that complex - just a PIC, little LCD, and a few buttons - but when one only has finite time and wants to make images more than circuits, one sometimes has to pay the piper :-). I do think his integration of many different sensors (some of which are very useful and not very pricey) is nice.

Gonna make some rotational streak photos in 3D? Be neat.

John

Hi Keith,
That is a world class page linked to world class work in every way.
I clearly remember when that was new work by Doc Edgerton. John's work is the best lighting I have seen combined with stop action flash.

I would like to know more about the lighting, how John got the short duration flash and the whole set up. I cc:'s a copy of this to John.

Good work.
Gordon

John,
>> ...as there was a lot of interest from group members last night.
> That's nice.

Again, the 'traffic' last night for the webpage (with a link to www.stereo3dgallery.net) was amazing.

Thanks again for making these stereo pairs available and maybe it will stir up some activity to try it with a microscope! With this in mind, I have added your ferrous sulphate (last update July 2, 2005) to the webpage as a demonstration image for polarized light microscopy.

> Many people need some aid to view 3D on a computer screen (I too find cross-eyed viewing
> difficult). One simple and popular aid is the Pokescope (www.pokescope.com)

Thank you for this suggestion - I will be getting one of these inexpensive viewers asap.

> Sorry for the long digression. But 3D is very cool....

Maybe it's a digression, but see response comment above.

> The very last one at www.stereo3dgallery.net, where 3 drops simultaneously explode was a 1 in 100 gig, ...

Not at all difficult to accept!

> ...but you need a beam-interupt digital delay line to light up
> events that last only a few milliseconds with a critically timed flash.

I'll have to go back and try and improve upon my aqueous solution dripping from a burette and breaking the LED beam in an off-the-shelf sensor part to trigger a delayed flash.

Regards, Keith

Given the continued, very strong interest in the reference webpage to John Hart's 2D/3D stereo work I'm wondering if a post to the Group of this nature is a pleasant digression - once in a while?

Of course, we need to know what is a reasonable 'once in a while'.
Perhaps once each month?

I keep stumbling over light microscopists that have ventured into some pretty exotic (and fascinating) photographic experiments. Such as the fellow in Europe that is capturing a bee in flight around flowers in his backyard!

As always, just a thought.
Regards, Keith