Greetings,
I appreciate those taking time to email about the black boxcar and
opinions shared therein.
And this will be the wave-off point for those not interested.
1. Tom's ideas regarding filters are well founded. The luxury of
Photoshop tools can help recreate, destroy, enhance or diminish the
actual use of photographic filters when the photo was shot, correct
the effects of chemical decomposition of a print that has taken place
over time or correct an image gone wild due to 'retouching.'
Using the RGB color channels individually is probably the most basic
tool to examine whether the scanner sensors recorded something else to
create the illusion or actual tonal shift. An RGB scan is made using 3
distinct sensors that each produce a different image due to the
wavelength of the light striking it. The resulting scanned image is
the collection of these 3 color sensors data being combined into a
color image. And with this color scan we can dissect what major shifts
nay have occurred during the scan.
2. The original of this image is a real photo postcard. I believe it
was chemically created as a green tone sepia card, as some RRPC's
were, to create a more colorful product to sell.
3. Eliminating the green hue by selectively eliminating all but one
color channel, gives us a chance to look at what the gray tone is.
When there is little change in the color sample numbers from each
channel we can assume the tone is relatively accurate between the
point-to-point samples. e.g. suit, car, buggy, umbrella, bowler hats.
4. I checked the RGB original and each RGB color channel at
approximately the same point on each object. The sample numbers are
consistent within a few numbers.
5. The herald clearly shows three distinct tones. Given the Sun's
elevation, angle to the object, similar tones can be found and
measured/sampled across this image if you keep the point angle
relative to one another and away from the shadows.
6. Bill's reference to a freshly painted narrow gauge door is well
taken. Having not seen the image in question and not knowing the Sun's
elevation, angle to the object, it's hard for me to make a comparison.
But I think a look might find the same type of similar tones could be
found and measured/sampled. In fact, as a reference, it might be
helpful to the boxcar image since there is proof of the actual color.
Just for the record, color can lie, too.
7. Jerry's point about orthochromatic film type is noteworthy but
panchromatic emulsions became available about 1905-1906 so it expands
the questions. Was this shot on film or a glass plate?
8. The only idea I will cast aside for now is whether or not the
railroad would actually paint any boxcar some color other than what
the paint drawing called for. Railroads do whatever they want,
whenever they want. One of the most famous railroad paint stories
involved the Great Northern. The shops ran out of Glacier Park Green.
It was time for a GN steam engine (S-2) to return to service. The
shops called the paint supplier and the engine returned to service
wearing Seattle Park Bench Green. Fact or fiction, either way it
illustrates the point.
Any railroad that paints new waycars orange - the Q's NE-12's - more
than likely had lots of other examples of paint experiments.
BTW - The Quincy book had some very profound examples of the problems
found when working with color scans. I'm going to take a look and see
if I can remember which ones had the problematic color channels. If I
hadn't been able to selectively choose the best color channel to
recreate the sepia tone, the image may not have been usable. I'll post
them if found.
If we only had some of NASA's imaging software (and a NASA engineer to
interpret the data) we might have more clues.
Randy Danniel
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Posted by: Randy Danniel <milepost206@mchsi.com>
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