Handbook for the TRIUS PRO-825C Issue 1 September 2020
18
Taking your first astronomical image:
I will assume that you are now set up with a focused camera attached to a
telescope with an operating sidereal drive. If so, you are now in a position to take a
moderately long exposure of some interesting deep-sky astronomical object (I will
deal with planets later). As most drives are not very accurate beyond a minute or
two of exposure time, I suggest that you find a fairly bright object to image, such as
M42, M13, M27 or M57. There are many others to choose from, but these are
good examples.
Use the finder to align on your chosen object and then centre accurately by using the
focus frame and a short exposure of between 1 and 5 seconds. The ’12-16 bit’ slider
in the focus frame allows you to adjust the image contrast if you find that the object
is too faint with a short exposure. Once properly centred and focused, take an
exposure of about 60 seconds, and observe the result. Initially, the image may
appear rather barren and show only a few stars, however, there is a great deal of
data hidden from view. You can get to see a lot of this, without affecting the image
data, if you go to the ‘View’ menu and select ‘Auto Contrast Stretch Image’. The faint
image data will then appear in considerable detail and I think that you will be
impressed by the result!
If you are happy with the image, go to the ‘File’ menu and save it in a convenient
directory.
A 1200 second exposure of the Rosette through an IDAS filter (non-linear
stretched)
