[LRflex] Re: Was: Concentration; Now: Colour of light.

Yeah.  What he said.....  :-)
 
Aram> From: neil@xxxxxxxxxxx> To: leicareflex@xxxxxxxxxxxxx> Subject: [LRflex] 
Re: Was: Concentration; Now: Colour of light.> Date: Thu, 17 Jul 2008 07:05:01 
-0400> > Hi David,> > Sorry for the "late" reply, as I'm on the digest only. 
You've received lots> of good information and suggestions from Ted, Etienne, 
and Aram, so what I> have to offer is a little expansion on your general quest 
to color correct> the light from various sources. Unfortunately, the link to 
your comparison> images didn't work this morning, so my comments are very 
general.> > > Date: Wed, 16 Jul 2008 07:03:32 -0700> > From: David Young 
<dsy@xxxxxxxxxxxxxxx>> > [...]> > The light on the Ball mill side is provided 
by some sort of lamps,> > the likes of which I've not seen before. The images 
have a yellow> > cast similar to that provided to daylight film when shot 
under> > tungsten light, but much more so.> >> > Experimentation has shown that 
the colours can be restored to some> > semblance of what I remember by reducing 
the colour temperature to> > 2000 Kelvin (my RAW software, Silkypix, will not 
permit going any> > lower). However, if I do this, although the colours come 
closer to> > what I saw, they take on a surreal look. While the mill's walls 
are> > starting to come close to their "natural" colour, the greens are> > 
still too weak, and the yellows much too strong. Not to mention that> > in 
spots, they disappear all together, when they really were there,> > in the 
mill!> >> [...]> > The main problem is that there has to be color content in 
order to adjust> it! While many light sources "color" a scene by having spikes 
at one or more> location in the color spectrum, they also emit light energy 
across much of> the rest of the spectrum. So, filtering out the spike(s) leaves 
a more> balanced scene because of the content in the rest of the spectrum.> > 
Light sources that only emit a narrow band of light will not provide> 
significant illumination (if any) in the rest of the color spectrum, so> there 
is nothing in the recorded image to adjust! making broad-based> adjustments 
such as changing the overall color temperature will only result> in filtering 
the light in the range of the illumination, so the image can> take on a 
posterized look.> > Just as our minds can "fill in the blanks" when viewing a 
b/w image, the> same happens under other monochromatic lighting conditions. I 
suspect that> there are details that aren't recorded in the b/w version of your 
image as> well, but the expectations may be different.> > Best regards,> > Neil 
Gould> > ------> Unsubscribe or change to/from Digest Mode at:> 
http://www.lrflex.furnfeather.net/> Archives are at:> 
http://www.freelists.org/archives/leicareflex/
_________________________________________________________________
Stay in touch when you're away with Windows Live Messenger.
http://www.windowslive.com/messenger/overview.html?ocid=TXT_TAGLM_WL_messenger2_072008

Other related posts: