Something for the aphid lovers

Charles Krebs · Post by **Charles Krebs** » Mon Jun 13, 2005 7:55 pm

Although I hang out in the microscopy section, I do look at the great pictures over here. I've noticed the "affection" for aphids as subjects, and from the posts here, became curious myself about the structure of the eye. So I took a few pictures with a low power microscope set-up. I don't think the people over in microscopy are all that interested in aphids (

) so I decided to put them here. (If the powers that be feel a need to move them that's OK)

While I was looking at the eye I also took some shots of the siphunculus, those two little tubes that stick up from the back of the abdomen. I don't know too much about their purpose... but they look pretty interesting!

twebster · Post by **twebster** » Mon Jun 13, 2005 8:32 pm

Hi ya' Charlie

Astounding aphid images, my friend

I have never seen the likes of these anywhere

The siphunculus is also known as a "cornicle". Aphids are really pretty amazing in a chemical sort of way. Those little spherules contained in the cornicles are scent and pheromone packets. These are used to scent-mark predators. When an aphid is attacked, these spherules are released through the cornicles and are deposited on the predator. Now, the aphid that is being attacked isn't helped much by this. The scents and pheromones are not repulsive to the predator. Rather, the scents and pheromones become attached to the predator and act as early warning signals to other aphids when approached by a scent marked predator. Cool

Best regards to all as always,

gunn · Post by **gunn** » Mon Jun 13, 2005 9:41 pm

Amazing images by Charles and an equally amazing explanation by Tom.

Now, I'm beginning to wonder, short of a microscope, would the MPE-65 be able to summon up sufficient magnification to define the eyes as did Charles' microscope here. Tom?

best wishes
gunn

twebster · Post by **twebster** » Mon Jun 13, 2005 10:14 pm

Hi ya' Ben

Now, I'm beginning to wonder, short of a microscope, would the MPE-65 be able to summon up sufficient magnification to define the eyes as did Charles' microscope here. Tom?

I really don't know. Charlie uses very high quality, high NA microscope objective lenses. The MPE-65 might be able to match the subject magnification with a little help from an extension tube but I doubt that it could match the resolution. Lighting also plays a big role in microscope resolution. I think it would be difficult to match this type of illumination using the MPE-65. This is just my guess, Ben.

Best regards as always,

MikeBinOKlahoma · Post by **MikeBinOKlahoma** » Tue Jun 14, 2005 12:13 am

Charles, these are amazing shots. Thanks for posting them. I've insisted I had no further interest in microscopy past my (fairly standard among the group here) work with a cheapo one in my youth. This shot makes me rethink my position!

Gunn, I doubt the MP-E-65 could pull this off. At 5x, filling the frame with an aphid is about the most I can do. Here's a link to a pretty big one at 3.5x for comparison:

http://www.photomacrography1.net/forum/ ... ght=turnip

acerola · Post by **acerola** » Tue Jun 14, 2005 1:39 am

That's me an aphid lover. All I can say: Wow!
Terrific pictures and I like the explanation from Tom also.

I understand reluctantly that the resolution is better for the microscope, but what about DOF, it seems plenty of DOF here.
I envy of such an equipment now... it will pass.

Thanks again. I'm waiting for others...

Charles Krebs · Post by **Charles Krebs** » Tue Jun 14, 2005 11:24 am

.... I guess I should fill in some "blanks" about these pictures... It's actually an interesting subject, as it touches upon the transitional area between photomacrography and photomicrography (ie: at what point do you "need" to switch techniques)

Ben.. these were taken at a magnification of 25X on the sensor of a Canon 20D. The siphunculus shots are full frame (left to right) but the eye shots are a pretty good crop from the full frame. To "second" Mike's response, I have a 65mm MPE and it is superb optically. It goes to 5X by itself, so it can't approach this magnification without lots of unrealistic additions such as a huge amounts of additional extension and/or teleconverters.

Shots like this could be done without a microscope. Typically the equipment that would be used are "macro" lenses in the 12mm to 20mm range mounted on bellows.

acerola... Depth of field is the other huge issue. No matter how you arrive at this magnification (camera+bellows, or microscope) the DOF is far too small to show the subject with one shot. (If you are using a lens with an aperture at these magnifications, you really can't stop down more than about f4, or else your resolution is drastically lowered because of diffraction.) The pictures in this post were done using a "stacking" technique. A series of pictures were taken (around 15-35) at slightly difference focus points and then combined using a program called Helicon Focus. In order to do this, the subject cannot move at all while the sequence is taken, and you must be able to move either the subject or the camera in extremely fine, smooth increments. This is where a microscope focus stage is very helpful. I have a variety of focus rails and bellows with focus rails "built in". As good as these are, I think their "movements" are marginally fine/smooth enough to do this type of thing at 25X.

For pictures in this "transitional range" where I don't use the microscope, I have set up a subject "stage" that uses a microscope focus rack to allow for these fine movements. It's much easier than trying to move the camera.

acerola · Post by **acerola** » Tue Jun 14, 2005 2:14 pm

Thanks again Charles. So it was stacked and not just your miracolous equipment. I shoot mostly handheld and I only stacked 2 or 3 images.
Good work good result...

Ken Ramos · Post by **Ken Ramos** » Tue Jun 14, 2005 7:11 pm

Great images as usual Charlie

and thanks to Tom for the explanation of those two "tail pipes" stick'n out the back. Kind of like a skunk arn't they?

Lee Daniels · Post by **Lee Daniels** » Wed Jun 15, 2005 4:20 am

Little late to the party here, but just want to add my "Wow"s to your amazing series here. Fascinating and, of course, technically perfect. Really super!

pwiles1968 · Post by **pwiles1968** » Wed Jun 15, 2005 10:20 am

COOL

Nice work, Have you done any work with CombineZ, is the Helicon much better? You may have seen I have taken a shine to stacking images not sure I would gat much out of another program though combine dose a good job for the stuff I do and it was free which is allways a bonus

nzmacro · Post by **nzmacro** » Fri Jun 17, 2005 5:13 am

I have a funny feeling, I might be in LOVE

Never imagined in all my dreams to see such high quality shots as this Charley. OUTSTANDING comes to mind.

Ok, theres that "nipple" on the eye as Charles called it. Fascinating to see it at this ratio. In fact I'll have to get Charles to see these Charley, just have to. Well the butt end stove pipes, awww heck that is neat. Yep, I am in love

All the best Charles, superb work and shots and superb work, superb work and its also superb work.

Danny.

Charles Chien · Post by **Charles Chien** » Fri Jun 17, 2005 7:05 am

This is just amazing!!! Thanks for the detailed information on the technique, Charles. These images are just beautiful.I think we should definitely archive images and posts like this, as it's of great value to the readers.

The last time I tried taking photos of aphid's eye, I was using a 17mm on bellows. But, I had great difficulty with both modeling light and flash - both of them were simply not powerful enough. I was basically focusing in the dark guided by the very dim highlights, and had to do post processing to "add" more light to the photos, which then affected the image quality greatly for the worse... I got some fiber-optic cable in hope to provide modeling light without more heat than there already was, but soon became busy and had not been able to get back to it since. If you would be able to let us know about your lighting technique, I would really appreciate it.

Thanks to Danny for pointing me to this wonderful post as well. Looking forward to seeing more of these. Thanks!!!

Charles Krebs · Post by **Charles Krebs** » Fri Jun 17, 2005 5:33 pm

Wow... you guys really do like your aphids!

The lighting was simply two fiber optic light-guides illuminating a translucent film container that was cut and fitted to surround the subjects as shown in the picture below. The light-guides were moved around until I was satisfied with the lighting on the subject. This provides directional, but quite diffuse light. I like it, but some prefer more "contrasty" light. Occasionally I will let one of the light-guides illuminate the subject directly, and keep the second lighting through the film container as "fill". With the immediate feedback from digital, it's easy to adjust things to make the lighting best fit the subject.

Below is a shot I made using this lighting and using the image stacking technique (with Helicon Focus). On the left is a completed image, made up from about 65 individual frames at different focus settings. On the right is one image from the "stack". You can see how futile it would be to try to show this subject with a single frame.

Charles Chien · Post by **Charles Chien** » Fri Jun 17, 2005 5:52 pm

Charles Krebs wrote:Wow... you guys really do like your aphids!

Well, I think I like yours a lot better - mine simply don't focus that well.

Thanks for the detailed information. I surely learn a lot from this, and enjoy this reading. It's was a little relief that I was on the right track getting the fiber optic cables for the lighting, if only I can get to do it...

All the best, and looking forward to seeing more of these great photos!