OT: Astronomy DV Check this out!
Spot|DSE
wrote on 11/4/2004, 12:14 AM
Comments
TorS
wrote on 11/4/2004, 12:33 AM
Sky's the limit, what?
Tor
Tor
Grazie
wrote on 11/4/2004, 1:06 AM
That's the point . .Sky is NOT the limit! . . . Atmosphere and all that? G
Liam_Vegas
wrote on 11/4/2004, 1:15 AM
Now this IS something I know a lot about.
It is quite incredible what amateur astronomers have been able to do with simple video cameras attached to telescopes.
One of the little projects I did a couple of years ago was to stream a 2-day conference on AstroImaging and one of the presentations was all about use video for capturing high resolution images of the moon and other objects.
You can check out a small sample from the AstroImage 2002 conference (sorry - video is in Real Format - just the way I did it back then)
It is quite incredible what amateur astronomers have been able to do with simple video cameras attached to telescopes.
One of the little projects I did a couple of years ago was to stream a 2-day conference on AstroImaging and one of the presentations was all about use video for capturing high resolution images of the moon and other objects.
You can check out a small sample from the AstroImage 2002 conference (sorry - video is in Real Format - just the way I did it back then)
R0cky
wrote on 11/4/2004, 11:14 AM
How this is done is by capturing video with webcams. many people modify the webcams to increase the exposure time limit to as much as a minute.
Then you use one of several freeware or inexpensive share ware programs that scan the video and evaluate each image for sharpness. (atmospheric motion is a big deal in astrophotography).
These programs then throw out all of the poor images and then "stack" or average the good ones while automatically aligning them. This combines as many as 1000 images into one.
This reduces the noise level by the square root of the number of images averaged and increases contrast and saturation.
You then can post process with deconvolution techniques which can increase sharpness quite a bit. Deconvolution is the inverse of what acoustic mirror does. You model the spread of the light by the atmosphere and then apply the inverse transform iteratively.
Also lots of photoshop processing can be done to bring out the fainter parts, increase detail in selected areas, so on and so forth. Some of the best astrophotographs have weeks of post work to get one image.
Then you use one of several freeware or inexpensive share ware programs that scan the video and evaluate each image for sharpness. (atmospheric motion is a big deal in astrophotography).
These programs then throw out all of the poor images and then "stack" or average the good ones while automatically aligning them. This combines as many as 1000 images into one.
This reduces the noise level by the square root of the number of images averaged and increases contrast and saturation.
You then can post process with deconvolution techniques which can increase sharpness quite a bit. Deconvolution is the inverse of what acoustic mirror does. You model the spread of the light by the atmosphere and then apply the inverse transform iteratively.
Also lots of photoshop processing can be done to bring out the fainter parts, increase detail in selected areas, so on and so forth. Some of the best astrophotographs have weeks of post work to get one image.