Tip & How-To about Optics

What are those SMALL letters with numbers on the star chart?

Those are OBJECTS in the sky that you can try to find and observe!

"M" objects- this is the Charles Messier catalog containing over 100 sky objects he discovered in the 17th century!

"NGC" objects- this is the New General Catalog by J.L.E.Dreyer produced in the late 1800s and early 1900s. It has over 7000 sky objects that you can observe. Some of these are very dim and only possible to see in larger telescopes or from a dark sky observing site.

"IC" - this is the later Index Catalog produced by Dreyer
http://seds.org/~spider/ngc/ngc.html Same web site

There are dozens of other sky catalogs! My computer GOTO telescope lists 30,000 objects in it's internal database.

Here is a very good star chart:

And here is a free monthly star chart:

I would also recommend that you download the free planetarium software Stellarium, install it on your computer, put in your location; and it will show you the sky for any time or date. The graphics of the sky on this free program are VERY good.

Another good FREE computer star chart is Cartes du Ciel. The free download is available here:

Clear Skies!


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science tech 262 manual

Can't find a manual. This is a 76mm reflector on a Alt/AZ mount.
1. During the day, put in the 20mm eyepiece and point to a object around 100 yards away.
2. Focus on the object
3. Align the finder to the object in the eyepiece
4, Set up at night, give the scope time to reach outside temperature
5. Point scope with finder at the moon. (More than half full will be too bright)
6 Use the lowest power eyepiece (highest number) and focus on the moon.
7. You may now use higher power eyepieces to observe.
8. Pointing the scope usually involves loosing 2 knobs to move the scope in up/down and side to side motion. There may be slow motion controls to adjust the scope as objects in the sky move.

Nov 27, 2011 | Optics

1 Answer

Cpc 1100 miracle or fail?i can observe sky objects same size and same quality with my celestron 70 eq and cpc 1100 ? i used different eye pieces but nothing changed.No nebula,no galaxy or better view of saturn.What's wrong with it??

WRONG-- completely wrong. No way a 70mm scope will show the same as a 11 inch scope. UNLESS you point them to a star. All telescopes show stars as simply a point of light they are TOO far away to see a disk. Objects in the night sky are tiny-- smaller than the tip of your finger held at arm's length. The scope must be pointed DIRECTLY at them or you will not see anything. What you need is a little bit of knowledge about the night sky--

Download this free software:


download this free monthly star chart:

and located an Astronomy club nearby and the members will help you learn the night sky.


Aug 30, 2011 | Optics

1 Answer

I recently purchased a second hand bresser messier and would like to find a manual on how to work it

All of Meade's manuals are on this web site-- however this scope is only sold in EUROPE--- there may be one similar to it on the web site below which you can use to help you assemble it.

The manual only has assembly instructions. It will not tell you how to find objects in the night sky--- or how to focus the telescope--- or which eyepiece to use. All this comes with experience and by talking with other amateur astronomers. Find a local Astronomy club and JOIN--- the members will help you--

Meade's manual web site:


Aug 16, 2011 | Meade Bresser 4702100 Messier R102...

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