boja gume

[TopMix]

Zašto ne mogu da otvorim ovaj snimak što je okačio Aleksdja 
Aaaa, otvorio sam ga, sa malom zadrškom... Sad još da ga nekako prevedem, pa da budem i ja pametniji 

[alexdja]

Evo ti tekst biće ti lakše...   


Compare Visual System of Fish to Human
By Dan, Derrick, Juveria, Tim


Fish: The Evolutionary Solution
•"Fishes are the evolutionary solution to a number of
mechanical, aural, optical, structural, electrical and other
engineering problems relating to the environment in which
they exist. They are complex organisms, or animals, and
their sensory systems have evolved to provide the
necessary functions to make the whole fish a viable entity
in the watery environment"



Color Blind
•Humans, who are only one species, and who can see all of
the colors of the spectrum have a trichromatic visual
system. They have blue, green and yellow/orange sensitive
cones in their eyes.
•The fish may be trichromatic, and have three color
pigments The retina of these fishes will have the cones
arranged in a matrix. This might be a blue sensitive cone
surrounded by green and orange/yellow sensitive cones.
•The fish may be dichromatic (deep water species) and have
two color pigments. The retina of such fish might be made
up of only two color sensitive cones, blue and green; in
which case it will be a blue sensitive cone surrounded by
green sensitive cones.



Beyond the Visible Spectrum
•Color vision is our visual systems
sensitivity to light photons in the band of
electromagnetic frequencies called the
visible spectrum. It goes from red, orange,
yellow, green, blue, indigo to violet. We do
not see infrared or ultra violet but some of
the fishes may see infrared and one species
at least, the blue, or slimy, mackerel, does
see ultra violet.



Some Similarities
•We and the fishes have an adaptive eye that is
sensitive to the illumination level. If the light level
is low or photon limited, there is no color vision.
The brightness of the color or brilliance depends
on the illumination. If the illumination is high the
color is light and bright. If it is low the color is
dark.
•We and the fishes need at least two color sensors
before the brain can discriminate color hue or
difference.



Gray Scale Vision
•The rods are for gray scale vision and merely count photons regardless
of color.
•In Humans the retina contains both rods and cones. Each rod has a
drop of Visual Purple, or Rhodopsin, on the tip. In bright illumination
this bleaches de-sensitizing the rod and protecting it from the bright
light. As the illumination degrades the visual purple is re-generated by
vitamin A and allows the rod to detect very low-level light photons.
The lack of vitamin A in the body can lead to "night blindness" or a
low level of gray scale vision.
•In fishes’ eyes the rods are physically retractable. When light levels are
high the rods are retracted into the back of the retina and covered with
a black melanin layer. When light levels fall and the cone sensitivity
degrades the rods move upwards to lie alongside the cones to provide
gray scale vision.



The Reflective Eye
•Some fishes have a Tapetum lucidum, a reflective eye,
similar to nocturnal animals. They have a reflective system
on the retina to reflect light which has already passed the
rods, back for a second chance at detection. The sight is
very slightly blurred but it is very sensitive.
•The fact that these species have a reflective eye creates
problems when fish are removed from photon limited
water conditions and/or flashed with cameras. They can be
heavily light shocked and become disoriented which does
not help their survival on release in crocodile infested
waterways.



The Eye
•Photoreceptor properties
•Dynamic retina


W. W. Norton
Human Photoreceptors


Kusmic et al. (1992)
•Retinal rods contain a visual pigment with max at
512 nm.
•Adult trout the retinal cone system consists of single
and double cones with pigments having peaks at
–453 nm (single cones and one member of double cones),
–530 nm (single cones and one member of double cones)
–598 nm (one member of double cones)






4 cpd

‘High’ Frequencies


‘Medium’ Frequencies


‘Low’ Frequencies


Species


Wheeler, 1981
•Teleosts
–Animal's ability to perceive stimulus a function of
temperature and season.
–Specialized features
•Reflective tapetum (part of pigmented layer of the eye, which
has an iridescent luster and helps to make the eye visible in the
dark)
•Area and temperature dependent distribution of visual
pigments
•Area-specific distribution of photoreceptor types






D
Wheeler (1981)
•Cyprinid (soft-finned mainly freshwater fish
typically having toothless jaws)
–At least 7 distinct photoreceptor types.
–The receptors are not only the first neural retinal element,
but also act as interneurons and display the first indication
of antagonistic spectral and spatial response properties.
–Produce the high spectral and spatial resolution at the
ganglion cell level.
–Bipolar cells form direct contacts with receptors and
ganglion cells. The bipolar cells therefore provide a direct
straight-through information transfer pathway.




D
Saszik, Bilotta (1998)
•Like other fish, the dark-adapted visual system of
the zebrafish can be influenced by water
temperature.
–Warm (28–30°C)
•Spectral sensitivity consistent with the rhodopsin absorption
curve


–Cold (22–25°C)
•Spectral sensitivity function that was the result of a
rhodopsin/porphyropsin mixture


–In addition, ultraviolet cones (362nm) contributed to
the dark-adapted spectral sensitivity function under
both temperature conditions.




D
Powers, Bassi, Rone, Raymond (1987)
•New rods are continually generated and
inserted across the entire differentiated
retina in juvenile and adult goldfish
–No other retinal cells share this characteristic




D
Mikolosi, Andrew (1999)
•Cerebral lateralization is revealed in the zebrafish
by preferential eye use.
–differs according to the visual stimulus that is being
fixated


•Right eye is used when the stimulus (or scene) is
such as to require a careful period of examination
in order to decide on a response.
•Left eye is used when the fish has to check
whether an identical stimulus has been seen
before.


D
The Double Cone
•The double cone is a cone with a secondary
cone wrapped about it.
•Birds, reptiles, fish, and amphibians all have
double cones.
•Scientists hypothesize that double cones
allow certain color processing functions to
happen at the cone instead of at the
ganglion.



The Double Cone Recept

The Cone Mosaic
•Cones in fish are arranged in a pattern in the
retina known as the cone mosaic.
•Two types of mosaics exist: Square and
Row
•Patterns are dependent on the species of
fish.
•No purpose for the mosaic has been found
yet.



The Cone Mosaic mosaics1%20copy
Zebrafish (Row Mosaic) Medaka (Square Mosaic)
The Cone Mosaic freshwatermosaic
coastallittoalmosaic
Coastalmosaic

Two major types of visual
pigments:
•Rhodopsins
•Porphyropsins
•Three other types that appear in some fish:
•Kynurenine (3-hydroxykynurenine) (370nm)
•Carotenoids (425-480nm)
•Mycosporine-like amino acid (300-360nm)
•Some fish, including the Japanese dace fish, carp and the
common goldfish can see UV light.



Visual System of Billfish
(marlin)
•Vision concentrated in forward and
backward directions
•Able to resolve 10cm object at 50m (typical
for fish)
•Billfish has larger than average eyes which
don't improve visual acuity, but are better
able to see while moving at high speeds
•Adaptation for predator



Visual System of Billfish
(marlin)
•Color photoreceptors concentrated in part of
eye that faces up
•Part of eye that faces down contains
photoreceptors sensitive to light
•Adaptation for clear-water environment



References
•www.vthrc.uq.edu.au:16080/ecovis/VisionRep.html
•www.vthrc.uq.edu.au:16080/ecovis/VisionRep.html
•www.aims.gov.au/pages/research/fish/fisheyes/fisheyes01.html
•www.pigeon.psy.tufts.edu/avc/husband/avc4eye.htm
•instruct1.cit.cornell.edu/courses/bionb424/students2004/mas262/neuroanatomy.htm
•instruct1.cit.cornell.edu/courses/bionb424/students2004/mas262/neuroanatomy.htm
•instruct1.cit.cornell.edu/courses/bionb424/students2004/mas262/neuroanatomy.htm

[TopMix]

Zahvaljujem se  , al imam jedno podpitanje...
Alex, kakav bi po tvom mišljnju mogao biti zaključak posle ovog stručnog teksta? Mislim, zaključak koji bi mogao biti od neke praktične koristi za jednog prosečnog varaličara ...

[alexdja]

Zaključak je jedino da je glupost reći jednostavno "ribe ne razlikuju boje", "vide crno belo", "samo nijanse sive" i tako dalje...

Zavisno od vrste ribe, kakvu strukturu oka i vid imaju, svetla (doba dana, dubine), zamućenosti vode, tako će određena vrsta videti u tom momentu...

Ovo ti neće puno pomoći u zaključku kako vidi smuđ, šaran, som ili kako da ga upecaš, ali će nekome možda pomoći da više ne generalizuje stvari i da nije sve tako jednostavno jer "ribe ne vide boje"...

[maverick]

Ja rekoh da je prezentacija u oku promatrača...

[twister011]

Kao sto rece Alex, a sto ja vrtim odavno, mante se tvrdnji kako smudj vidi, kako razmislja i sl........ Normalno je teziti da se sto vise upozna i prati, ali tvrditi pomenuto je ravno ........

[dus]

a prevoditelj 

[TopMix]

Od tog naucnog saznanja da smudj nekako razlikuje boje, pa do primene te teze u praksi, radi efikasnijeg pecanja i boljeg ulova ... mislim da je jako velik razmak.
E sad, svako ko uporno menja boje varalica na pecanju, pa u nekom momentu zvekne smudja, voleo bih da mi objasni da je to samo zato sto je proradila ta i ta boja i da  to nije splet okolnosti i slucajnosti... Pa da u to sve ubaci i razradi detalje, kao sto su prelamanje svetlosti, bistrina vode, dubina, doba dana, sunce, oblaci, mesec...
Ako je neko to sve pohvatao i provalio, sta da kazem, svaka cast   

[alexdja]

Ja se slažem sa svime što si napisao. 

I ja isto kažem svaka čast onome ko je to sve pohvatao!

Akcenat je na tome da vidi boje, a koju kad želi da pojede i zašto, to je već drugo pitanje... 

[twister011]

Vidis Tope, nije stvar u tome. Tako bi svi imali jasan stav o bojama, ako bi se sve svodilo na slucajnost.
Problem je u totalno drugim situacijama.
Kada menjas a oni, ne "on" vec gomila redom udara samo na jednu boju. Ja prvi ne razmilsjam mnogo o bojama. Pogledam vodu i znam sta cu bacati. Problem nastaje kada u grupi od vise pecarosa, samo jedan dobija na neku, obicno "nelogicnu" boju, a ostali nista. Kada i drugi stave tu boju, i kod njih postaje produktivno.
U takvim situacijama sam redovno "proklet" i ne zanima me ulov vec samo "naucna" saznanja, pa u sred cuga menjam ponovo. Vise puta sam doziveo, da nam se javljao samo na jednu odredjenu. Sam tesko prihvatam tu pricu, ali itekako verujem u nju.
Naravno, merilo su mi samo kolege u cije pecanje takodje verujem. Cisto da bi iskljucili price, vibracija, prezentacija, ko zna a ko ne zna. I u najblizem drustvu nekima verujem vise nekima manje

[Hunter]

jesenas na staroj dravi kod mene smudjevi fino gruzu na silikonce.lovimo samo nas dvoje,ostali 0 bodova.ja sam ih uglavnom dero na sakura slit shad u ayu boji 1,5 -3 gr jig i fish arrow flash j i sakura solit tail isto u ayu boji na drop shotu.druge boje makar sam forsiro ni griza.dojdem do pepe koji je ulovio svaki dan isto ko i ja i imam sta vidit.peca na relax kopyto 5 i sa 10 grama jigom,naravno mora vuci troduplo brze nego ja jerbo je dubina vode samo metar i pol.relax fluo zuti..kaze samo tu boju uzimaju,na druge ni mrc.
e jebesga sad.dam mu slit shada da proba bacati i na njega dva dana nema ni griza ,a ja uredno lovim i dalje.
suma sumarum,jebo smudjeve i nas!

[twister011]

Taman sam zbog prvog dela, planirao da zamolim za prevod, ali mi onda poslednja recenica razjasni sve 
Mada bih pre rekao, ebo samo nas. Smudjevi vode svoj zivot, a mi smo ti koji im se trpamo i jos pride pro.eravamo

[twister011]

Sad se setih necega, na sta bi voleo da dobijem jasan odgovor. Posebno od onih koji zagovaraju "slepocu smudja" 
Kako to da je za stuku potpuno normalno da je boja jedna od klucnih stvari, sto niko ne dovodi u pitanje, a kad je smudj u pitanju, e tu i krv ponekad kaplje. O beskrajnim diskusijama (ne mislim na ovaj forum) da ne pricamo

[rj]

teško je uporedit lov smuđa i štuke ...štuka se uglavnom lovi u plićoj i bistrijoj vodi tako da je boja izraženija ...
mene jedna druga stvar zbunjuje ....kako može boja muže igrat ulogu na dubini 10-12 m voda relativno zamučena (Dunav) a igra ulogu ...koji qurac on vidi razliku recimo žuta i nježno zelena ...jednu uzima drugu ni dirnit 

[tole]

jbg...možda kad bi se stavio u smuđevu poziciju pa pogledao malo sa dna prema površini bi neke stvari bile jasnije.... često mi se događalo da samo mala razlika u boji donosi rezultate, druga nijansa, varalica koja je malo izbledjela na suncu bolje lovi od iste iz kese ili obrnuta...

...kad lovim voblerima često se desi da oni stariji, izbledjeli daju bolje rezultate od novih koji su još u punom sjaju....ne znam, kad dođem na vodu pokušam na osnovu nekog iskustva odabrat varalicu i boju iste, ako neće onda kombiniram i često se desi da ona "ajd da probam i ovo" na kraju bude dobitna kombinacija