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First attempt at DSO for
Stronge brothers
After the wonderful view of
M13, the Hercules Cluster, at the EAAS star party, we just had to have
a go at imaging it. This time we knew it would take a lot longer exposure
and more sensitive CCD than the Dimage 7 had. We used our Starlight Xpress
MX7C CCD camera. This is a very sensitive colour CCD camera specifically
designed for astronomical use that can be used in unguided or guide mode
as the CCD has a progressive scan. The chip in the camera is a Sony EXview
CCD, with 752x582pixels.
With the Meade 10inch LX-200
on the polar mounting, we fine tuned the tracking by adjusting the mount
at 15 minute intervals using the built-in "refined polar alignment"
of the LX-200. Every time we did this the tracking and GOTO became more
accurate to a point where the GOTO is accurate to less than 2 arc-minutes.
This means that subjects will be centred in the eyepiece at high magnifications
and the CCD can be slotted in without the hassle of fine tuning the subject
in the CCD due to the small area covered by the chip.
The photo below is taken using
the Meade 10inch LX200, f3.3 focal reducer and the Starlight Xpress MX7C
CCD camera. Unfortunately, because of work commitments, there was only
time to take 2 exposures, each 60 seconds long. The telescope was unguided
so we were relying on the accuracy of the polar alignment to make sure
the stars were round and not streaked. The 2 images were stacked and processed
in Registax and then levels adjusted in Paint Shop Pro 8.
EAAS Mars Star Party
At the EAAS Mars Star Party
of 27th August 2003, at the Big Collin Picnic Area north of Ballyclare,
the sky conditions were excellent. 25 miles north of Belfast really makes
a big difference to the sky and M31, the Andromeda Galaxy, was naked eye
visible. Mars' closest approach was memorable but the sheer number of
Messier objects were a sight to behold. On that night, I had just brought
my digital camera with me to have a go at Mars.
The wide field image below
was taken with a Minolta Dimage 7, 5 megapixel camera.
ISO100
Shutter speed 30 seconds
Aperture f2.8
Focal length 28mm
You can see Mars in the constellation of Aquarius and, in the original
image you can even pick out Uranus!!!
The image of Mars
was taken with a Meade 10inch LX-200 at F10, and a Minolta Dimage 7. 47
individual frames were taken. Because Registax only stacks at resolutions
below 1024x1024, all of the images were cropped using Irfanview. Each
image was taken at ISO100, f2.8, 1/30 second exposure at maximum zoom
on the camera. After cropping, the 47 frames were aligned and stacked
using Registax and then processed in Paint Shop Pro 8. The Red channel
was separated from the Blue and Green and realigned for a sharper image.
Mars only rises to 19 degrees at our latitude so we are fairly happy with
this image.
First sightings of Mars
Well, it's been a long time
since there has been really good imaging night's as the sky hasn't really
got dark but since the start of August we have been looking to the SE
for our first sighting of Mars. We have found a new problem while imaging
Mars - there is a lot of infrared light coming from Mars and this is making
focusing and sharp images a problem. We haven't received our infrared
filter as yet so we tried using a Broadband filter instead and this certainly
brought out a lot more surface detail. Here is our latest efforts.
The image to the left was taken
approximately 18 miles South of Belfast in a very dark site and you can
clearly see the benefits with the better contrast in the image.
We reprocessed our Mars
avi in the new Registax version 2 beta and we produced a significantly
better image. The new Registax can automatically compensate for Red shift
and this resulted in a much sharper image.
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