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Couple shots from the route home.
Posted: Thu Oct 23, 2008 3:46 am
by Javelin
It's getting harder to stop for photo opportunities because it gets dark early now.
Chipmunk
Some kind of fungus that looks like sea shells
Re: Couple shots from the route home.
Posted: Thu Oct 23, 2008 5:51 am
by KevinBarrett
Lovely! Thanks for sharing Javelin!
This is completely unrelated to the quality of your pictures, just an aside, but I notice that the OOF twig in the foreground is fringed in red, whereas the OOF twig in the background is fringed in cyan, both of which are a light-against-dark contrast. Any idea what caused this? I just thought it was interesting.
Re: Couple shots from the route home.
Posted: Thu Oct 23, 2008 6:06 am
by [SiC]
KevinBarrett wrote:Lovely! Thanks for sharing Javelin!
This is completely unrelated to the quality of your pictures, just an aside, but I notice that the OOF twig in the foreground is fringed in red, whereas the OOF twig in the background is fringed in cyan, both of which are a light-against-dark contrast. Any idea what caused this? I just thought it was interesting.
It is called Longitudinal (Axial) Chromatic Aberration, but I'm not that good at optics to tell you why this occurs
/Z!
Re: Couple shots from the route home.
Posted: Thu Oct 23, 2008 6:23 am
by KevinBarrett
Cool! You learn something new every day!
Re: Couple shots from the route home.
Posted: Thu Oct 23, 2008 9:12 am
by [SiC]
KevinBarrett wrote:Cool! You learn something new every day!
Yep, at least on a good day
Longitudinal chromatic aberration, also known as axial color, is the inability of a lens to focus different colors in the same focal plane. For a subject point on the optical axis the foci of the various colors are also on the optical axis, but displaced in the longitudinal direction (i.e. along the axis). This behavior is elucidated in Fig. 1 for a distant light source. In this sketch, only the green light is in sharp focus on the sensor. The blue and red light have a so-called circle of confusion in the sensor plane and are not sharply imaged.
Blatantly stolen from here:
http://www.vanwalree.com/optics/chromatic.html 
BR,
/Zeb!
Re: Couple shots from the route home.
Posted: Thu Oct 23, 2008 3:22 pm
by Javelin
I hadn't noticed that. usually I don't even look for it unless it's on a really bright background. I'll have to look at the raws again to see if thats what it is, thanks .
Re: Couple shots from the route home.
Posted: Thu Oct 23, 2008 8:05 pm
by Dr. Harout
It is something easily fixed on ACR or LR or... (chromatic aberration)
Re: Couple shots from the route home.
Posted: Fri Oct 24, 2008 3:09 am
by Javelin
I'm surprised to see it to be honest. this lens with make a spectacular job of PF with leaves against a sky but it's rare to see in a shot like this. but I tried the ACR tools for fringe and it has zero effect on the reed or the green fringe... is it possible it's something else that caused it ?
Re: Couple shots from the route home.
Posted: Fri Oct 24, 2008 3:25 am
by Javelin
if someone wants to give it a try (removing the PF) here is the raw .. I can't seem to make it work.
http://www.uranium-238.com/~stf/web/Glenn/DSC00484.ARW