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Knobbed Helmet Shell

Knobbed Helmet Shell
Photo Information
Copyright: Mehmet Atatur (matatur) Gold Star Critiquer/Gold Star Workshop Editor/Gold Note Writer [C: 1054 W: 245 N: 1626] (5312)
Genre: Animals
Medium: Color
Date Taken: 2008
Categories: Molluscs
Camera: Nikon Coolpix 8800
Details: Tripod: Yes
Photo Version: Original Version
Theme(s): A study in Conchology (seashells) 1 [view contributor(s)]
Date Submitted: 2008-12-15 12:22
Viewed: 5902
Points: 72
[Note Guidelines] Photographer's Note
Today, I'll try to introduce another fine mollusc specimen from the Mediterranean-Aegean system which also inhabits the neighbouring Atlantic region. This is a Knobbed Helmet Shell, aka Prickly Helmet Shell, -Cassidaria (= Galeodea) echinophora- a denizen of moderate to deeper sandy bottoms, a predatory species which feeds on sea urchins and some other echinoderms. This species belongs to the Helmet Shells of the family Cassidae, formerly known as CAssididae, usually quite large predatory sea snails with large, thick walled shells and a horny operculum. But Knobby Helmet Shells are not so big, their height (from apex to the end of siphonal canal) rarely reaches 11 cm. They possess a medium spire with a pointed apex, and a large body whorl with five spiral ridges, the two posterior rows with characteristic blunt tubercles or nodulose bumps, these are fainter on the next two rows and almost indistinct on the last one. Spiral cords can be seen between the suture line and the whorl shoulders, these become smooth anteriorly. In mature specimens the outer lip of the wide aperture forms a flared and thickened varix (partly visible here delineating the bottom part of the shell), which is distinctly toothed within (will try to demonstrate these in a future post). The inner lip forms a broad shield like structure over the visible shell axis or columella. The roughly semicircular aperture draws into a siphonal canal of moderate length anteriorly, which displays a dorsally oriented bent. The shell is usually yellowish brown with whitish nodules or tubercles, the aperture is whitish.
This specimen was collected while snorkelling from a sandy bottom with a depth of 8 meters offshore of Kalabak, Outer Bay of Izmir, and photographed under unilateral daylight with open-shade conditions, with some weak side illumination from a contra placed matt white cardboard passsive reflector, against a dark BG.

JoseMiguel, rousettus, maurydv, eqshannon, jaycee, Jamesp, xTauruSx, ramthakur, uleko, Argus, eng55, Juyona, izler, Alex99, banaei_nikon, boreocypriensis, SelenE, Dis. Ac., zulfu, Ozgur70, jusninasirun has marked this note useful
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ThreadThread Starter Messages Updated
To BobH: on Knobbed...matatur 3 12-20 05:02
To Argus: on Knobbed...matatur 1 12-17 02:05
To rousettus: on Knobbed...matatur 2 12-15 14:35
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Critiques [Translate]

Epeyce bir aradan sonra kavkı serinizden bir kare daha görmek pek güzel oldu, hocam. İlk bakışta bir Rapana venosa olsa gerek demiştim. İngilizce adından araştırınca Galeodea echinophora olduğunu gördüm. Nasılsa doğrusu notlarınızdan öğreneceğiz. siyah fonda dorsalden güzel bir görünüm. ışık ayarlarınız her zamanki ustalığınızla onu üçboyutlu görünümünde göstermiş. elinize sağlık. iyi geceler, selamlar.

  • Great 
  • volkan Gold Star Critiquer/Silver Workshop Editor [C: 497 W: 10 N: 4] (2425)
  • [2008-12-15 12:30]

Hi Mehmet,
This is a very exquisite sample of the knobbed helmet shell
it sure looks like a helmet :)
nice plain black BG and the details are marvellous..
Very well composed my friend..
TFS this image.

  • Great 
  • nglen Gold Star Critiquer/Silver Workshop Editor/Gold Note Writer [C: 2883 W: 30 N: 9683] (36145)
  • [2008-12-15 12:37]

Hi Mehmet. Once again a thing of beauty from you. Your use of the light and fine detail with natural colours, makes this a first class picture. It stands out from the black BG so well. I would collect shells as a child but i never saw them as things of beauty but today thanks to you i do. TFS.

Hi Mehmet,

nice sharp picture from these shell.
Beautiful colours and good of details,


  • Great 
  • batu Gold Star Critiquer/Gold Star Workshop Editor/Gold Note Writer [C: 1079 W: 293 N: 4497] (16383)
  • [2008-12-15 12:45]

Merhaba Mehmet,
a fine and sharp picture of the shell shown with great depth of field.
I like the visible details and the natural colour.
Best wishes, Peter

Merhaba Mehmet,
What a beauties and interesting forms are nature capable of.
You did it pretty good in the lighting side, with all these textures, colours and shines over the shelf.
The black of the background works pretty well to stand out the mollusc.
Great work and thanks for share.
My best regards,

thanks for introducing this one, Ori

Merhaba Mehmet, beautiful mollusc with fantastic light and colors, splendid sharpness, very well done, ciao Silvio

Merhaba Mehmet,
un'altra fantastica immagine da aggiungere alla tua splendida galleria di conchiglie, eccellenti POV, DOF e composizione con BG scuro, eccezionale nitidezza con ottimi dettagli, bellissime le tonalità dei colori.

Absolutely superb lesson. I feel as though I am back at college...1964-71...took me a while...You are indeed the superb Master Teacher sir! The almost beyond perfect way you present..and the time it takes for one to read and think, then search perhaps on the now Internet form ore...this is your specialty! I am always feeling honored to see these immense works...even if small is large..

  • Great 
  • jaycee Gold Star Critiquer/Silver Workshop Editor/Gold Note Writer [C: 2454 W: 10 N: 8044] (25460)
  • [2008-12-15 18:50]

Hi Mehmet,

It's easy to tell how this shell got its name. It does look like a helmet. The shape is wonderful. Beautiful colors, shadings and details against the black background. Your posts are more than excellent illustrations - combined with your notes they are lessons on a subject most of us have never learned.


  • Great 
  • Jamesp Gold Star Critiquer/Gold Note Writer [C: 1369 W: 9 N: 6334] (18906)
  • [2008-12-15 23:37]

Hello Mehmet

A lovely shot - great pov with superb detail and lighting.


Selam Mehmet hocam, harika bir makro. Detaylar mükemmel. Elinize sağlık.

  • Great 
  • Rosa Gold Star Critiquer [C: 56 W: 0 N: 0] (0)
  • [2008-12-16 1:14]

Hello Mehmet,
what a wonderful perspective and composition.
Have a wonderful day

Merhaba Mehmet Bey,yine çok güzel bir ışık ve nefis detaylarla sunulmuş bir kare,ellerinize sağlık,saygılar:)

The 'helmet' association is very appropriate in the case of this shell, Mehmet. In the picture, it does look like a knobbed helmet.
The three-dimensional impression is strong is this well managed image.
It is yet another wonder of nature you have shown us in the most impressive manner.
TFS and regards.

  • Great 
  • uleko Gold Star Critiquer/Gold Star Workshop Editor/Gold Note Writer [C: 3396 W: 172 N: 3310] (10940)
  • [2008-12-16 7:09]

Hello Mehmet,
This does indeed look like a helmet! Excellent capture showing very fine details and colours. A beautiful find from your own 'territory'! Interesting note too!
Many thanks and best wishes, Ulla

  • Great 
  • Argus Gold Star Critiquer/Gold Star Workshop Editor/Gold Note Writer [C: 5038 W: 260 N: 15594] (50626)
  • [2008-12-16 7:44]
  • [+]

Merhaba Mehmet,
Another fine portrait of a mollusc executed with you high technical standard from a pleasing POV to show us the fine shape and texture of this Knobbed Helmet Shell.
Thanks for sharing this delight and once again for your excellent educational note.
Kind regards,

BTW has Harun Yahyah's Atlas of Creation become popular in Turkey?

  • Great 
  • eng55 Gold Star Critiquer/Silver Workshop Editor/Gold Note Writer [C: 1256 W: 42 N: 1976] (5892)
  • [2008-12-16 8:17]

Merhaba Mehmet Bey,
Harika bir fotograf,sanki ekrana elimizi uzatıp tutabilecekmişiz
gibi canlı görünüyor.Siyah fon seçiminiz sayesinde tüm ilgi ana
obje üzerinde toplanıyor.Detaylar,pozlama ve kadraj
da kusursuz.Notunuzla birlikte ansiklopedi sayafası
niteliğinde bir çalışma ortaya çıkmış.
Tebrikler,ellerinize sağlık!

  • Great 
  • Juyona Gold Star Critiquer/Silver Workshop Editor [C: 2232 W: 10 N: 2971] (16891)
  • [2008-12-16 11:19]

Hola amigo,
bella concha,
color y fino foco,
presentación y detalles...

  • Great 
  • PaulH Gold Star Critiquer/Silver Workshop Editor/Gold Note Writer [C: 1137 W: 26 N: 3879] (13882)
  • [2008-12-16 11:57]

Hi Mehmet,
great notes and presentation as always from you, you manage to find another jewel at the bottom of the ocean! Lovely details and colours and a fascinating looking creature..

  • Great 
  • izler Gold Star Critiquer [C: 1387 W: 3 N: 9] (44)
  • [2008-12-16 14:22]

merhaba hocam
aydınlatma, fon, renkler, netlik ve detayların yine başarılı olduğu bir yakın çekim paylaşmışsınız
ellerinize sağlık

  • Great 
  • Alex99 Gold Star Critiquer/Gold Star Workshop Editor/Gold Note Writer [C: 4072 W: 133 N: 7096] (23735)
  • [2008-12-16 20:55]

Hi Mehmet.
Simply blameless picture of an amazing shell. I thinks this is one of the best shots. Terrific reproduction of the texture and colouration of the subject. Lighting as well as the composition are the best too. My congratulations.

Hi Mehmet,

nice sharp picture from these shell.
splendid sharpness

  • Great 
  • efsus Gold Star Critiquer/Silver Workshop Editor/Gold Note Writer [C: 415 W: 11 N: 843] (3947)
  • [2008-12-17 10:59]

Merhaba Hocam,
Uzunca sayılabilecek bir bayram tatili esnasında TN den uzak kaldım. Bu karenizi görünce siteyi ve sizleri ne kadar özlediğimi anladım. Çocukken aldığımız ve bizi peşinde koşturan o güzelim şekerleme tadında, bir bayram hediyesi bu. Çekim tekniği ve detaylar konusunda söylenecek tek şey, herşeyin mükemmel olduğu olabilir ancak.
Ellerinize sağlık hocam yeni çalışmalarınızda görüşmek dileği ile. Sağlıkla kalın.


Hoca 1 güncük ara vermiştim o gün de siz bunu yüklemişsiniz. Gözümden kaçmış. Muhteşem yüzey detayları ile yine harika bir çekim olmuş. Elinize sağlık.

ps. metni hala bekliyorum...

  • Great 
  • SelenE Gold Star Critiquer/Gold Star Workshop Editor/Gold Note Writer [C: 2249 W: 65 N: 4205] (13972)
  • [2008-12-17 14:36]

Merhaba Mehmet Bey,
Your model stands out very well against the dark background. Good POV, composition and details as usual. Thanks for the informative notes as well.
Selam ve sevgiler

  • Great 
  • joey Gold Star Critiquer/Gold Star Workshop Editor/Gold Note Writer [C: 1739 W: 224 N: 6872] (24909)
  • [2008-12-17 14:39]

Hi Mehmet,
a great capture of this aptly-named knobbly shell :-)
Very clear and crisp.
Spot-on exposure.
Superb contrast.

Well done,

  • Great 
  • sayat Gold Star Critiquer/Gold Note Writer [C: 280 W: 0 N: 258] (1457)
  • [2008-12-18 2:49]

Ekrandan taşan, üç boyutlu gibi kabaran bir güzellik. Işık yönetiminizdeki ustalık her resimde yeniden etkiliyor beni. Arka plan, her zamanki gibi, olağanüstü. Tebrikler, teşekkürler.

  • Great 
  • BobH Silver Star Critiquer/Gold Note Writer [C: 40 W: 8 N: 192] (650)
  • [2008-12-18 3:52]
  • [+]


Glad you like my abstract ice pictures. The subjects are not likely to be replicated in your back yard!

Your latest shell is one of the best. You are a master of lighting for still life shots.

It is clear that Mollusca are your first love, but have you considered shooting things such as fruit or cut flowers in your studio? I suspect the results would be quite worthwhile. Likewise some closer macro / supermacro work on your marine specimens, such as Hippopus or Haliotis or sea urchin.

Think about it!

Best regards,


  • Great 
  • zulfu Gold Star Critiquer [C: 685 W: 0 N: 2] (43)
  • [2008-12-18 7:55]

Yanal ışılandırma ile harika bir yakın çekim olmuş Mehmet hocam. Detaylar ve renkler mükemmel. Teşekkürler.

  • Great 
  • cako Gold Star Critiquer/Gold Note Writer [C: 485 W: 0 N: 772] (3395)
  • [2008-12-20 3:23]

Merhaba Mehmet bey
yine keyifle izleyeceğimiz enfes bir kavkı karesi daha ellerinize sağlık.

Hola Mehmet, hace ya muchos días que no me acercaba a tu especial galería, pero como me hiciste un comentario vine...
Bella toma donde sin duda la luz y los colores son los protagonistas. Buen enfoque. Quizás el ángulo algo cerrado, aunque eso va a gustos.
Un abrazo: Josep Ignasi.

  • Great 
  • Janice Gold Star Critiquer/Gold Star Workshop Editor/Gold Note Writer [C: 3277 W: 148 N: 6163] (18832)
  • [2009-01-11 11:51]

Hello Mehmet
This is another well-taken photo of the sea shell. The colours and details show up[ well,

Hi Mehmet,

This knobbed helmet is so well captured. I like the details of very interesting pattern on the shell. TFS and best regards.


  • Great 
  • foozi Gold Star Critiquer/Gold Note Writer [C: 2791 W: 0 N: 6696] (25839)
  • [2009-04-25 5:18]

Merhaba Dr. Mehmet,
such a lovely anf fine composition and attractive presentation. I like the name very much, quite special and interesting to me.


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