by Chris Peterson » Sat Jun 13, 2020 4:43 pm
Sa Ji Tario wrote: ↑Sat Jun 13, 2020 4:33 pm
From its inception, photography was in Black and White and was controlled with high contrast and a range of grays that displayed fine details that color films cannot capture. The photographic plate was in principle a thin glass plate covered with a silver emulsion that reacted with light, in astronomy they were used until the 70 '-80' of the last century.
To those who do not know this story, I recommend that you see the techniques used by David Malin of the AAT of Australia and they will see how astronomical color images "are not" "they are made"
Of course, now we have tools that can expand the amount of information we can absorb even from single-channel data. Such data (when the intent is scientific) is rarely left as a simple grayscale image, but instead has its intensity information mapped to color (i.e. pseudocolor) since we can discern more colors than we can intensities.
The situation with precise filters and electronic detectors is very different from the situation with film. We now have linear detectors that have vastly greater dynamic range than film, much higher resolution than film, and are- in every respect- superior to film for every purpose.
I most commonly create B&W astroimages. But it's an aesthetic choice, not a scientific one. If science is the goal, I collect as many different wavelength channels as possible, and process them to enhance information content, not aesthetics.
[quote="Sa Ji Tario" post_id=303098 time=1592065981]
From its inception, photography was in Black and White and was controlled with high contrast and a range of grays that displayed fine details that color films cannot capture. The photographic plate was in principle a thin glass plate covered with a silver emulsion that reacted with light, in astronomy they were used until the 70 '-80' of the last century.
To those who do not know this story, I recommend that you see the techniques used by David Malin of the AAT of Australia and they will see how astronomical color images "are not" "they are made"
[/quote]
Of course, now we have tools that can expand the amount of information we can absorb even from single-channel data. Such data (when the intent is scientific) is rarely left as a simple grayscale image, but instead has its intensity information mapped to color (i.e. pseudocolor) since we can discern more colors than we can intensities.
The situation with precise filters and electronic detectors is very different from the situation with film. We now have linear detectors that have vastly greater dynamic range than film, much higher resolution than film, and are- in every respect- superior to film for every purpose.
I most commonly create B&W astroimages. But it's an aesthetic choice, not a scientific one. If science is the goal, I collect as many different wavelength channels as possible, and process them to enhance information content, not aesthetics.