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Dune race animals

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AGILIS View Drop Down
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Post Options Post Options   Thanks (0) Thanks(0)   Quote AGILIS Quote  Post ReplyReply Direct Link To This Post Posted: 03 Jul 2014 at 6:34pm
are there any nuclear power stations in the area Keith
   LOCAL ICYNICAL CELTIC ECO WARRIOR AND FAILED DRUID
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Post Options Post Options   Thanks (0) Thanks(0)   Quote liamrussell Quote  Post ReplyReply Direct Link To This Post Posted: 13 Jul 2014 at 4:00pm
Originally posted by Caleb Caleb wrote:

So were you able to compare intensity between images to say definitively that the northern males aren't more or less green than the southern ones? Can't see how you'd do that without some calibration.

For my soil samples, I photographed each one next to some red, green and blue tapes, so that any variation in intensity and colour of the light source, and any variation in the camera's response could be calibrated for- it was surprising how much this varied even under seemingly identical conditions.

Unfortunately I couldn't calibrate the images, as the standard way to do this is to include a white disc in the photo. I just took the photos so I could recognise individual lizards if I recaught them. However the photos were taken under reasonably consistent conditions and other studies using the sane techniques did not require any adjustment as there was so little difference in intensity between the images. I think the digital images vary a lot less than using film as there is no room for difference due to the development process.

It's no a perfect situation but I thought interesting given what I had to work with.
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Post Options Post Options   Thanks (0) Thanks(0)   Quote Caleb Quote  Post ReplyReply Direct Link To This Post Posted: 14 Jul 2014 at 10:40am
Fair enough.

Did you consider converting the RGB colour values to HSV (hue/saturation/value)? 

That might quantify the differences in a more intuitive way- e.g. changes in darkness/lightness would change S and V, but the underlying 'greenness' should only show up in H.
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Post Options Post Options   Thanks (0) Thanks(0)   Quote AGILIS Quote  Post ReplyReply Direct Link To This Post Posted: 14 Jul 2014 at 6:05pm
What we all seem to forget is its great that LA are found in surrounds other the the South west of England I can remember having a look for them when I was serving in the RAF in the early sixties in the sand dunes around the Altcar area but sadly I only see a few lv Peter are there any colonies in the area KEITH

Edited by AGILIS - 14 Jul 2014 at 6:14pm
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Post Options Post Options   Thanks (0) Thanks(0)   Quote Peter Quote  Post ReplyReply Direct Link To This Post Posted: 15 Jul 2014 at 5:39pm
Hi Keith :)   I only know of the Sefton coast colonies and the Welsh reintroductions.   The furthest North colony of La that I know of is an introduced colony on a specific Hebridean island that has been surviving for approximately ten generations but in this instance the animals are of heathland origin and so far are showing little or no sign of developing the features typically associated with dune race animals.
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Post Options Post Options   Thanks (0) Thanks(0)   Quote Peter Quote  Post ReplyReply Direct Link To This Post Posted: 15 Jul 2014 at 8:20pm
Keith, there are almost certainly La at the rifle ranges in Altcar, but access is difficult.   There was pretty severe damage to the population at Formby last year due to a big fire, so Altcar could potentially hold animals that could recolonize, but there is very little free sand at Altcar due to creeping willow and other vegetation taking hold.
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