Obviously this photo began life as a colour picture, and only then was converted into black & white. But it is a mystery to me how Explorer and several photo editors can display the thumbnail in colours. Of course the photo is b&w when I open it, but even when copied, the new thumbnail is still in colours. I wonder if a photo somehow is carrying a thumbnail photo of itself? I have never seen this before - but of course I very seldom have any black & white pictures. Actually, in this case as in most cases, I think I would prefer the colourful "orange" version ;-)
Edited:
I have not edited this photo; it was downloaded in black & white.
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EXIF
---- Image Information ---------------------------------------------------------
Filename: 001_Citroën DS.jpg
File size: 665 KB (681 437 bytes)
Dimensions: 2376 x 1800
Bit depth: 24
Created: 8. oktober 2005 18:57:46
Changed: 16. juli 2012 00:22:33
---- Description ---------------------------------------------------------------
Title OLYMPUS DIGITAL CAMERA
---- Picture Taking Conditions -------------------------------------------------
Audio note No
Camera data Yes
Text information Yes
Created 8. oktober 2005 18:57:46
Digitized 8. oktober 2005 18:57:46
Modified 8. oktober 2005 18:57:46
Flash No
Exposure time 1/250 s
Aperture 3.2
Max. aperture 3.25
Focal length 38.10 mm
Focal length (EQ35mm) 250 mm
ISO 200
Digital zoom ratio 0.00
Exposure bias 0
Metering mode Pattern
Exposure mode Auto exposure
White balance Automatic
Exposure program Creative program (biased toward depth of field)
Orientation Normal
Sharpness Normal
Contrast Normal
Saturation Normal
Gain control Low gain up
Scene capture type Standard
Camera Make OLYMPUS CORPORATION
Model C750UZ
Software v753u2-86
Compression JFIF Compression
Color representation YCbCR
DPI 72.00
Exif version 2.20
Flashpix version 1.00
Colorspace sRGB
Flash - detailed Flash did not fire, Compulsory flash suppression
File source Digital camera
Scene type A directly photographed image
Custom image processing Normal process
Subject distance range Distant view
Compression quality SQ
Firmware SX753
Keywords No
Digital signature No
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The thumbnails in "Large icons"-view In Explorer (big b/w pop-up thumbnail created by QTTabbar):

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As seen in Zoner 14 PRO photo editor (the "orange" photos are the thumbnails of 3 b&w photos):

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The actual photo (click to enlarge):
