|
i put this on a reply to the tarantula image from peter... relevant to here
Hydrogen alpha emmissions are in the red end of town, your oxygen 111 are in the blue/green, both being emmisions, your reflection nebs are scattered blue light and some of the darker dust will be into the browns.
the colors of various objects will depend on the type of light coming from them combined with the cameras ability to handle those same wavelengths.
An unmodded DSLR does not have a high response to the red Ha so its diminished , if you shoot the cats paw, it really only emits in the Ha so even with DSLR you will get reds (not a lot) the same goes for the horsehead,
however some objects (in this case we have the tarantula) there is a high amount of the O3 possibly also some reflection in there too, in an unmodded camera this will swamp the little red you have, and voila a blue tarantula.
Some objects have a combination of both and as a result red plus blue looks purplish, you will find this in say the Carinae Nebula.
there is no wrong or right, its just what your camera percieves. Insects see well into the ultra violet and probably see everything different to us completely. there has been much perhaps condescending talk about unmodded cameras. i personally dont care, blue/red whatever its just that part of the spectrum you have captured.
enjoy thats what counts.
clive
|