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Fly Spotters


Fly Spotters
Photo Information
Copyright: Joe Kellard (joey) Gold Star Critiquer/Gold Star Workshop Editor/Gold Note Writer [C: 1739 W: 224 N: 6872] (24909)
Genre: Animals
Medium: Color
Date Taken: 2008-05-18
Camera: Canon EOS 400D (Rebel XTi), Sigma 180mm f/3.5 Macro + 1.4x Converter, Digital ISO-400, Kood 72mm UV filter
Exposure: f/14.0, 1/200 seconds
Details: Tripod: Yes (Fill) Flash: Yes
More Photo Info: [view]
Photo Version: Original Version
Date Submitted: 2008-05-30 2:33
Viewed: 3504
Favorites: 2 [view]
Points: 62
[Note Guidelines] Photographer's Note
This is another close-up of the eyes of the Scarce Chaser. I hope you all aren't bored of these yet!

I used flash this time which I normally hate to use for close-ups of insect eyes but it was my only choice.

I hope you like it!

Anyway, here is some info on compound eyes :-)

The arthropod (e.g., insects, crustaceans) eye is built quite differently from the vertebrate eye (and mollusk eye).

Arthropod eyes are called compound eyes because they are made up of repeating units, the ommatidia, each of which functions as a separate visual receptor.

Each ommatidium consists of a lens (the front surface of which makes up a single facet) a transparent crystalline cone light-sensitive visual cells arranged in a radial pattern like the sections of an orange
pigment cells which separate the ommatidium from its neighbors.
The pigment cells ensure that only light entering the ommatidium parallel (or almost so) to its long axis reaches the visual cells and triggers nerve impulses. Thus each ommatidium is pointed at just a single area in space and contributes information about only one small area in the field of view.
There may be thousands of ommatidia in a compound eye with their facets spread over most of the surface of a hemisphere. (The photo, courtesy Carolina Biological Supply Company, shows the compound eye of Drosophila melanogaster.)
The composite of all their responses is a mosaic image — a pattern of light and dark dots rather like the halftone illustrations in a newspaper or magazine. And just as in those media, the finer the pattern of dots, the better the quality of the image.
Grasshopper eyes, with relatively few ommatidia must produce a coarse, grainy image. The honeybee and dragonfly have many more ommatidia and a corresponding improvement in their ability to discriminate ("resolve") detail. Even so, the resolving ability of the honeybee eye is poor in comparison with that of most vertebrate eyes and only 1/60 as good as that of the human eye; that is, two objects that we could distinguish between at 60 feet could only be discriminated by the bee at a distance of one foot.

Flicker effect
The compound eye is excellent at detecting motion. As an object moves across the visual field, ommatidia are progressively turned on and off. Because of the resulting "flicker effect", insects respond far better to moving objects than stationary ones. Honeybees, for example, will visit wind-blown flowers more readily than still ones. Link to illustrated discussion of honeybee navigation.

Resolution and Sensitivity
Arthropods that are apt to be active in dim light (e.g., crayfish, praying mantis) concentrate the screening pigments of their ommatidia into the lower ends of the pigment cells. This shift enables light entering a single ommatidium at an angle to pass into adjacent ommatidia and stimulate them also. With many ommatidia responding to a single area in the visual field, the image becomes coarser. The praying mantis probably can do little more than distinguish light and dark in the evening.
The shift in pigments does, however, make it more sensitive to light than it is in the daytime as more ommatidia can detect a given area of light.

Color vision
Some insects are able to distinguish colors. This requires two or more pigments, each of which absorbs best at a different wavelength.
In the honeybee, four of the visual cells in each ommatidium respond best to yellow-green light (544 nm)
two respond maximally to blue light (436 nm)
the remaining two respond best to ultraviolet light (344 nm)
This system should enable the honeybee to distinguish colors (except red) and — as the image shows — behavioral studies verify this.

Ultraviolet vision
Why ultraviolet vision?
Television camera tubes are also sensitive to ultraviolet, as well as visible light, but their glass lens is opaque to ultraviolet. (This is why you can't get tanned — or synthesize calciferol — from the sunlight passing through window glass.)
Using a special ultraviolet-transmitting lens, Eisner and his coworkers at Cornell have demonstrated that many insect-pollinated flowers appear to the honeybee quite different from the way they appear to us. The sharp contrasts between flowers that appear similar to us partly explains the efficiency with which honeybees secure nectar from only one species of flower at a time even when other species are also in bloom.

Thanks!

crs, alikox, eqshannon, Juyona, zulfu, eng55, boreocypriensis, Amadeo, aes_thor, uleko, jaycee, nglen, marhowie, Art_R, wuta, hester, Adanac, JoshLewis, rousettus, Necipp, cicindela, liziafa has marked this note useful
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Critiques [Translate]

  • Great 
  • crs Gold Star Critiquer/Gold Note Writer [C: 469 W: 0 N: 922] (3551)
  • [2008-05-30 4:04]

Hi Joe,

This is a great macro photo. The image is of a very good quality showing razor sharp details. Very good use of light (even if flash) rendering well the colors and enabling viewer to see even the finest details. Excelent view over the surface of the compound eye.

Very ibteresting and usefull information in your note.

Thank you for sharing,
Cristian

Excelente acercamiento Joe, con una justa luz y un enfoque y profundidad muy precisos. Buen documento.
Saludos: J. Ignasi.

Bonjour,
Excellent cliché. On pourrait lui compter les poils !
Bonne journée.
clnaef

Video/vision...all right brained things which I enjoy as much as does Jane...there is a connection with right and left brain using the technique which is why a bi-polar person has difficulties on some days. Not that this is a professional notion, but coming from a person as me who is well studied and has bi-polar disorder:-)
Bob

  • Great 
  • Juyona Gold Star Critiquer/Silver Workshop Editor [C: 2232 W: 10 N: 2971] (16891)
  • [2008-05-30 7:31]

Hola Joe,
excelente macro,
foco y detalles maravillosos,
color y composición,
saludos

  • Great 
  • zulfu Gold Star Critiquer [C: 685 W: 0 N: 2] (43)
  • [2008-05-30 8:05]

Hi Joe another superb macro capture of the eyes. TFS.
Greetings, Mehmet

  • Great 
  • eng55 Gold Star Critiquer/Silver Workshop Editor/Gold Note Writer [C: 1256 W: 42 N: 1976] (5892)
  • [2008-05-30 8:48]

Hi Joe,
Amazing close up.Very well caught.
Thanks for posting.

Hi Joe,
Another extremely and extraordinary macro capture focused of the eyes of the Scarce Chaser my friend. Did you know or heart this proverb? :) "Eyes do not say lie" :p
TFS and Cheers Owlman :o)

Bayram

Hola joe, secillamente, excelente aproximación. Un saludo

Hello Joe!
Another great close-up, Excellent details and colours. Well done!
cheers
Adrian

  • Great 
  • uleko Gold Star Critiquer/Gold Star Workshop Editor/Gold Note Writer [C: 3396 W: 172 N: 3310] (10940)
  • [2008-05-30 9:56]

Hello Joe,
You must have crept up very slowly on this one! I wonder how close you were? Superb shot, fantastic sharpness and interesting details. Hardly beautiful (needs a shave!!) but the colours are lovely.
Many thanks and cheers, Ulla

  • Great 
  • PeterZ Gold Star Critiquer/Gold Star Workshop Editor/Gold Note Writer [C: 5137 W: 166 N: 13121] (49139)
  • [2008-05-30 10:39]

Hello Joe,
Another amazing macro. Perfect details and splendid colours. Great composition.
Regards,
Peter

  • Great 
  • jaycee Gold Star Critiquer/Silver Workshop Editor/Gold Note Writer [C: 2454 W: 10 N: 8044] (25460)
  • [2008-05-30 11:52]

Hi Joe,

I'm not bored - each of these macros fascinate me. This shot ranks up there with your best. Wonderful clarity - we can see every hair. The eyes are amazing.

Jane

  • Great 
  • pvs Gold Star Critiquer/Gold Star Workshop Editor/Gold Note Writer [C: 1127 W: 254 N: 3161] (14464)
  • [2008-05-30 11:53]

Hi Joe,

Again a nice one,with a frontal POV,no we are not bored with them,I know they are quite hard to approach,you did a great job again,thanks

Paul

  • Great 
  • nglen Gold Star Critiquer/Silver Workshop Editor/Gold Note Writer [C: 2883 W: 30 N: 9683] (36145)
  • [2008-05-30 12:19]

Hi Joe. Each one is different so i will never get bored.This one has fine detail and very sharp focusing.rich colours and good use of the flash. I do like the detail you have in the eye. so well done TFS.
Nick..

Have a nice weekend.

Hi Joe,
You're doing some great work in the land of micro mf..you can count the hairs :)
I like the in your face comp and POV here, fine details.
Well done & have nice weekend!
Howard

oh my goodness, what a closeup. Amazing macro, you defintiely have one hell of a macro lens, the DOF and detail is fabulous

  • Great 
  • Art_R Gold Star Critiquer/Silver Workshop Editor/Gold Note Writer [C: 244 W: 20 N: 839] (3892)
  • [2008-05-30 20:27]

Hi Joe , great macro stunning detail and very good noise handling for the 400 iso , I think the flash worked good for you here , strong color and composition , very nice work. your notes are fascinating too , a good understanding of their eyes sure does help to get closer to them ;-)

TFS
regards
Art

  • Great 
  • arfer Gold Star Critiquer [C: 2731 W: 0 N: 0] (0)
  • [2008-05-30 20:44]

Hello Joe

Amazing close up.
The details are wonderful.
Well focused with sharp details.
Very good colours.
TFS

Rob

  • Great 
  • lousat Gold Star Critiquer/Gold Star Workshop Editor/Gold Note Writer [C: 6595 W: 89 N: 15659] (65489)
  • [2008-05-31 4:00]

Hi Joe,we aren't bored ,these pics are a very great scoops!!This in particular is most impressive,the quality is over the top and i know how isn't easy to take so perfectly this dragonflies!!My best compliments,a great masterwork,have a nice day,Luciano

Hi,

On the road now and just marking now, will be back later...

Pekka

WOW Joe, amazing portrait with fantastic details, splendid sharpness, very well done, ciao Silvio

Your macros are just masterpieces! WOW!!!

I run out of things to say except WOW!

  • Great 
  • wuta Gold Star Critiquer/Gold Note Writer [C: 855 W: 2 N: 617] (2142)
  • [2008-06-01 11:22]

Hello Joe , Exelent macro shot from the face , great details colours light pov dof , and yuo have lenzes , great job tfs ,Greetings Teunie .

  • Great 
  • hester Gold Star Critiquer/Silver Workshop Editor/Gold Note Writer [C: 1515 W: 18 N: 3165] (11638)
  • [2008-06-01 12:10]

Hi Joe

You certainly do some amazing macro shots. The details on this are amazing, especially the eyes. Pin sharp, wonderful close framing and wonderful colour. It has a nice smile too :)

TFS

Karan

  • Great 
  • EOSF1 Gold Star Critiquer/Gold Star Workshop Editor/Gold Note Writer [C: 1393 W: 119 N: 5267] (23955)
  • [2008-06-01 14:16]

Fantastic macro Joe! Incredible sharpness and details and a perfect overall quality, well done! Thanks!

Mario

  • Great 
  • Adanac Gold Star Critiquer/Gold Note Writer [C: 1273 W: 1 N: 6188] (21378)
  • [2008-06-01 16:41]

Hello Joe,
This image reminds me I need to shave. Wonderful macro work here Joe, fantastic details, wonderful depth of field and bright colors. Thank you for sharing.
Rick

Hello Joe,
excellent macro on fly's large compound eyes. ocels look very nice. sharp details, symetry, focus, POV and composition perfect. also colors superb. thanks for sharing, have a nice weekend
Ahmet

Hello Joe, this is probably one of the best macro shots I've seen of this dragonfly. The details are just amazing closeup. Perfect composition, and it looks perfectly symmetrical, works very well for this type of image. Sorry p.t. Rgds, Necip

Hello Joe,
This is one of the best portrait of dragonfly I have seen till now! Wonderful details, amazing sharpness and... "eye-contact" ;>
Also the note is very interesting and informative.
All the best from Poland,
Radomir

Hi Joe,
EXCELLENT EXTREME CLOSE-UP!!!
Nice colors and details.
Well done!!!
TFS Malgosia

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