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11 Jan 2003 Sample raw image |
Tom's scope (8" newtonian reflector), Logitech QuickCam Pro 4000 (no
lens) Tom's back garden, near Southampton, -4°C, slightly
hazy
This was our first attempt at capturing M42. Whilst the
unmodified webcam is easily capable of capturing a recognisable image
of a planet, a diffuse object such as a nebula wasn't so easy to
capture, even the brightest nebula wasn't bright enough to show up on the
webcam's longest exposure of 1/15 second.
However, collecting ~200 such images, using Registax to combine
them and then making aggressive use of Photoshop did indeed reveal
nebulosity - our quest to improve our images of M42 had begun...
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11 Jan 2003 160 images 1/15 second |
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23 Jan 2003 1100 images 1/15 second |
Tom's scope, Logitech QuickCam Pro 4000 (no lens) Tom's back
garden, -1°C, slightly hazy
This is a repeat of the previous attempt only this time using 1100
images instead of 160. We wrote a program to read the three 16bit FIT
files that Registax can produce and convert them into a 48bit RAW format
which can be opened in Photoshop. This extra information has
resulted in smoother shading after the gamma curves were tugged
around but there is still plenty of room
for improvement. We also benefitted from having a
clock motor for the first time. |
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17 Feb 2003 Sample raw image |
Tom's scope, Logitech QuickCam Pro 4000 SC Long Exposure
Modified Tom's
back garden, -2°C, hazy, full moon.
This is the first attempt at imaging M42 after the SC long exposure
modifications were made. As the sample raw image shows, nebulosity
can clearly be seen with a 5 second exposure, as can signs of drift where
the scope wasn't accurately aligned and signs of atmospheric
turbulence.
The resulting image was compiled from only about 25 exposures of 5
seconds and is already noticeably more detailed than the previous effort
with more than a thousand exposures of 1/15 second. Signs of
nebulosity can be seen extending to the edges of the frame indicationg
that we needed to widen our efforts. |
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17 Feb 2003 25 images 5 seconds |
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21 Feb 2003 |
Tom's scope, Logitech QuickCam Pro 4000 SC Long Exposure
Modified Tom's back garden, brrr.
Having spent some time working out how to get the webcam and laptop not
to crash, this effort combined seven sets of stacked images all combined
in Photoshop to make an image with a larger field of view - M43 can be
seen in the upper left quadrant of this image. The extent of
nebulosity can be seen very clearly in this image suggesting that we need
to cover a much wider area still. The effects of light pollution are
also in evidence, future efforts to improve our images will involve
travelling to a much darker site. |