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Old 31-03-2011, 08:47 AM
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madbadgalaxyman (Robert)
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madbadgalaxyman is offline
Join Date: Mar 2011
Location: Brisbane
Posts: 935
Equipment that makes Object finding easier

Suzy, to some degree, the following comments on equipment are also designed for others who are relatively new to observational astronomy. So, apologies if you already know some of this stuff. But it is the fruit of my long experience with using many & varied telescopes.

Regarding your equipment, as I mentioned, having some means of lining up the telescope, before you move to an accurate lining up with a finder, is an least in my view. I use a Telrad, with some of the glowing red rings (that are superposed on the sky) blocked out; because their brightness tended to wipe out the object that was supposed to be behind the rings. Cheaper option is the "two rusty nails on the tube" trick.

They say that a bad workman always blames his tools, but really, the right equipment can make finding objects 1000% easier! If the telescope moves so much that the object is moved out of the field, even when you give it a very slight tap, it is time either to adjust the mount or to get a better mount.
( I once had a heavy german equatorial mount that "weighed a ton", and a tap on the telescope tube barely moved the object that I had already centred in the field)
(Despite all the raves about how wonderful Dobsonian mounts are, the smoothness and stability of some heavy equatorial mounts beats most Dobsonians. )

Your mount problems remind me of those with my first telescope at age 10...... when the slightest knock caused the telescope to move well away from the object I was viewing.

Seriously, get a 30-40 mm eyepiece when you are trying to find objects and to get them into the field of your telescope. (Preferably an eyepiece with a 60-75 degree apparent field)
This avoids the "narrow porthole in the sky" that is your telescope field, missing the target object.
There are plenty of eyepiece experts about in the equipment form, and I used to be one of them, but I am not up on the very latest hardware.

Finders: In my view, a finder with a 5 degree field is not nearly optimal. A seven degree field shows a sky area that is twice as large. The object is therefore much more likely to be in the field of the finder after your initial lining up of the telescope.
Further, the wider Finder field shows much more of the star pattern, so recognition of "where I am in the sky" is much easier. Don't even consider using a 30mm finder! 50mm or 60-70 mm, is much much much better. The dreaded 30mm finders are a recipe for frustration and time-wasting, during observing.


Regarding Starcharts versus computerized finding & pointing; Someone who never hops from star to star in finding their objects never develops first-hand familiarity with the sky.
It was the strange things that I sometimes found on my way to the target object, that gave me a real sense of the interest of the universe. Me and some of my observing companions got to know some sections of the Milky Way better than our own backyards.

{{ For a hint at my astronomical play/work, look in the astro-imaging forum ; recent posts regarding Malin 1 and NGC 4945

Another hint: I sometimes take a microscope to the observing site, in case it clouds over! Bugs in the soil are the "galaxies" of biology. }}

Last edited by madbadgalaxyman; 31-03-2011 at 10:37 AM. Reason: one more comment to add
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