Archived posting to the Leica Users Group, 2015/02/10

[Author Prev] [Author Next] [Thread Prev] [Thread Next] [Author Index] [Topic Index] [Home] [Search]

Subject: [Leica] IMG: Moonrise from the Space Needle
From: boulanger.croissant at gmail.com (Peter Klein)
Date: Tue, 10 Feb 2015 02:19:55 -0800

We were treated to quite a show during our anniversary dinner.
<https://www.flickr.com/photos/24844563 at N04/16304267069/>

I'd like some advice on a technical problem with this picture, and in fact
with all of the pictures I took of the city from atop the Needle.  Red car
tail lights turn white.  It isn't overexposure, because it happens even on
shots that I deliberately underexposed drastically, where all the RGB
values are under 255. In shots with any decent city detail, the red channel
does hit 255, but the green and blue are much lower.  Lowering the exposure
in post, or using highlight recovery has no effect.

This doesn't happen with larger areas of red light where the pixels have
the same values as the little tail lights. But taill lights turn white, as
do other points of colored light like the blue and green Seahawks colors
that still adorn some construction cranes. The key seems to be that the
light sources are just a few pixels in diameter.

Maddeningly, on the onscreen preview, the tail lights appear red. But when
I "develop" the JPG, they turn white.They also turn white if I blow up the
onscreen preview to 50% size or larger.

The camera is an Olympus E-M5 with 45/1.8 lens, and the RAW developer is
Capture One v. 7.1.2. Here's a screen clip of the whole picture, followed
by a section with and a string of car rears blown up to 400% so you can see
what's going on with the pixels.
<
http://gallery.leica-users.org/v/pklein/temp/SpaceNeedleMoonriseScrPreview.JPG.html
>
<
http://gallery.leica-users.org/v/pklein/temp/SpaceNeedleMoonriseCars400pct.JPG.html
>

Advice, anyone? Is this just an inevitable result of the Bayer array, or is
there a way to fix it?

--Peter


Replies: Reply from douglas.sharp at gmx.de (Douglas Sharp) ([Leica] IMG: Moonrise from the Space Needle)
Reply from mark at rabinergroup.com (Mark Rabiner) ([Leica] IMG: Moonrise from the Space Needle)