Telescope device to combine all spectrums of light.

You may need to clarify that one. There is only one spectrum of light,
composed of its many wavelengths. Filters work by transmitting desired
wavelengths and blocking all the others, so that part is certainly doable.
The light could then be recombined, but to what end? Are you trying to
create a true color image from red, green, and blue components?

If you mean, is it possible to combine data from various regions of the
spectrum (gamma ray, x-ray, ultraviolet, visible, infrared, and radio) to
come up with a single false-color image, then yes, it can be accomplished
digitally.



"David" wrote in message
om...
I am looking for a telescope filter or device that will filter and
combine all spectrums of light and then display in full color. Does
such a device exist? If so, where can I get one?

Thank you,

Dave

"Bill Nunnelee" wrote in message hlink.net...
You may need to clarify that one. There is only one spectrum of light,
composed of its many wavelengths. Filters work by transmitting desired
wavelengths and blocking all the others, so that part is certainly doable.
The light could then be recombined, but to what end? Are you trying to
create a true color image from red, green, and blue components?

If you mean, is it possible to combine data from various regions of the
spectrum (gamma ray, x-ray, ultraviolet, visible, infrared, and radio) to
come up with a single false-color image, then yes, it can be accomplished
digitally.




Thanks for helping me clarify my questions. Yes, there is only one
spectrum of light, which is composed of many different wavelengths.

Yes, I am trying to create a true color image from red, green, and
blue components.

I have taken the light from a telescope and separated it into Red,
Blue, and Green. Now what I am trying to do is re-combine all four so
that I have one color image. Is it possible to do this with a
mechanical device or could I do this with software? You said it could
be accomplished digitally. How would I go about doing this?

Thank you,

Dave

"Bill Nunnelee" wrote in message hlink.net...
You may need to clarify that one. There is only one spectrum of light,
composed of its many wavelengths. Filters work by transmitting desired
wavelengths and blocking all the others, so that part is certainly doable.
The light could then be recombined, but to what end? Are you trying to
create a true color image from red, green, and blue components?

If you mean, is it possible to combine data from various regions of the
spectrum (gamma ray, x-ray, ultraviolet, visible, infrared, and radio) to
come up with a single false-color image, then yes, it can be accomplished
digitally.




Thanks for helping me clarify my questions. Yes, there is only one
spectrum of light, which is composed of many different wavelengths.

Yes, I am trying to create a true color image from red, green, and
blue components.

I have taken the light from a telescope and separated it into Red,
Blue, and Green. Now what I am trying to do is re-combine all four so
that I have one color image. Is it possible to do this with a
mechanical device or could I do this with software? You said it could
be accomplished digitally. How would I go about doing this?

Thank you,

Dave

Photoshop.


"David" wrote in message
om...
"Bill Nunnelee" wrote in message
hlink.net...
You may need to clarify that one. There is only one spectrum of light,
composed of its many wavelengths. Filters work by transmitting desired
wavelengths and blocking all the others, so that part is certainly
doable.
The light could then be recombined, but to what end? Are you trying to
create a true color image from red, green, and blue components?

If you mean, is it possible to combine data from various regions of the
spectrum (gamma ray, x-ray, ultraviolet, visible, infrared, and radio)
to
come up with a single false-color image, then yes, it can be
accomplished
digitally.




Thanks for helping me clarify my questions. Yes, there is only one
spectrum of light, which is composed of many different wavelengths.

Yes, I am trying to create a true color image from red, green, and
blue components.

I have taken the light from a telescope and separated it into Red,
Blue, and Green. Now what I am trying to do is re-combine all four so
that I have one color image. Is it possible to do this with a
mechanical device or could I do this with software? You said it could
be accomplished digitally. How would I go about doing this?

Thank you,

Dave

Photoshop.


"David" wrote in message
om...
"Bill Nunnelee" wrote in message
hlink.net...
You may need to clarify that one. There is only one spectrum of light,
composed of its many wavelengths. Filters work by transmitting desired
wavelengths and blocking all the others, so that part is certainly
doable.
The light could then be recombined, but to what end? Are you trying to
create a true color image from red, green, and blue components?

If you mean, is it possible to combine data from various regions of the
spectrum (gamma ray, x-ray, ultraviolet, visible, infrared, and radio)
to
come up with a single false-color image, then yes, it can be
accomplished
digitally.




Thanks for helping me clarify my questions. Yes, there is only one
spectrum of light, which is composed of many different wavelengths.

Yes, I am trying to create a true color image from red, green, and
blue components.

I have taken the light from a telescope and separated it into Red,
Blue, and Green. Now what I am trying to do is re-combine all four so
that I have one color image. Is it possible to do this with a
mechanical device or could I do this with software? You said it could
be accomplished digitally. How would I go about doing this?

Thank you,

Dave

"David" wrote in message
om...
"Bill Nunnelee" wrote in message
hlink.net...
You may need to clarify that one. There is only one spectrum of light,
composed of its many wavelengths. Filters work by transmitting desired
wavelengths and blocking all the others, so that part is certainly
doable.
The light could then be recombined, but to what end? Are you trying to
create a true color image from red, green, and blue components?

If you mean, is it possible to combine data from various regions of the
spectrum (gamma ray, x-ray, ultraviolet, visible, infrared, and radio)
to
come up with a single false-color image, then yes, it can be
accomplished
digitally.




Thanks for helping me clarify my questions. Yes, there is only one
spectrum of light, which is composed of many different wavelengths.

Yes, I am trying to create a true color image from red, green, and
blue components.

I have taken the light from a telescope and separated it into Red,
Blue, and Green. Now what I am trying to do is re-combine all four so
that I have one color image. Is it possible to do this with a
mechanical device or could I do this with software? You said it could
be accomplished digitally. How would I go about doing this?
I think you need to do some research into 'colour spaces'.
The only way to record a 'true colour' image, is to use a spectrograph,
where an intensity for every single wavelength of light is recorded... 'True
colour', as used in the context of computer screens, or images, is instead
referring to making something that reproduces as closely as is possible
within the limits of the reproduction medium the visual effect. This is
limited by the 'gamut' of the output device.
So (for instance), if you are producing an image on a computer monitor, with
normal red/green/blue phoshors, the range of colours that can actually be
reproduced, are limited (at the black end), by the fact that the
un-illuminated screen surface is not 'black', the range of intensities
produced by the phosphors themselves, and the fact that the band of colours
produced by a phosphor, will not exactly match the range of colours to which
the sensors in the eye respond. This is why companies needing to get
reproduction that is as accurate as possible, will use quite expensive
systems to colour match the screen to the real world. With these,
measurements are taken off the screen, to read the real responses of the
phosphor, and the values used internally are adjusted to bring these as
close as possible to the required results. Even with this, the results
locally on the screen can vary, because of non-linearities in the scan, and
in the phosphors themselves...
The same range of problems, exist with the imaging device in the first
place. Hence achieving 'true colour', is quite complex. There are then
questions as to whether the colour that should be reproduced is the one that
would be seen on the Earth's surface, or the one seen from space?. In the
latter case, the position in th sky becomes significant, with the atmosphere
selectively attenuating some light frequencies (and bending them even more),
as you approach the horizon.
There is quite a good basic tutorial about 'colour', on the Minolta site at:
http://www.minolta.com/yourcolours/c_base/index.html

However that being said, I suspect you may be talking about normal imaging
solutions.
Normally the 'starting point' for 'representative' colour imaging, is to
either photograph a daytime colour chart using the same imaging system, or
to mathematically calculate the sensitivity of the imaging system, and
filters at the different frequencies. In either case, the 'weight' that has
to be applied to each component of the colour image, can then be estimated.
The images can then be adjusted in relative intensity using these weights,
and the colour reproduction generated by combining these in allmost any
imaging program. For instance, both PhotoShop, and Corel PhotoPaint, allow
three monochrome images to be combined to produce a colour output. The more
'astronomically orientated' packages (like Maxim, and AstroArt), include the
ability to define the weights to be applied to each image, and to re-align
the colour planes to give the best results. This type of package, then
attempts to produce a 'real looking' colour from the incoming images.
However nothing is perfect. An example of a 'problem', comes with narrow
spectral lines (like O-III), recorded in some nebulae. This is a
'blue/green' colour, and as such falls right on the dividing line between
the blue, and the green filters. Now if the blue filter lets through even
fractionally more of this colour, than the sensor in the eye, the colour
will appear too blue, when compared with the 'real' colour, for a
combination that still gives a perfect 'white'. Unfortunately, because of
the impossibility of matching the eyes response perfectly at all the stages,
'narrow band' colours like this, will allways image incorrectly, and it then
becomes a matter of either accepting the incorrect colouration, or of
tweaking the responses so that these are correct, and then accepting that
white will be slightly miscoloured.
There are programs to help solve the 'best' weight levels to use for
imaging, such as:
http://www.astrovid.com/astrocalc%20...calculator.htm
http://www.astrodon.com/Color%20Filters.html
The second has an overall description of this problem, that is well worth
reading.

Now that all having been said, combining your images would normally be done
in software (you could potentially do it in hardware, by making each image
into a B&W slide, and projecting these through three slide projectors, each
with a colour filter attached that matched the passband of the original
filters used to take the images). You may well allready have a package that
can do this. If not, then the choice will depend on what other features you
want from your imaging package. The 'best' converntional package, is
probably PhotoShop.

Best Wishes

"Roger Hamlett" wrote in message
...

Hence achieving 'true colour', is quite complex.

All you have to do is right click on your desktop, select Properties,
Settings, and select True Color from the drop-down box. :-)

"Stephen Paul" wrote in message
...

"Roger Hamlett" wrote in message
...

Hence achieving 'true colour', is quite complex.

All you have to do is right click on your desktop, select Properties,
Settings, and select True Color from the drop-down box. :-)
That still only gives you 'true color', not 'true colour'... :-)

Best Wishes