Star Maps

These days you have two different options for star maps.   You can use the newfangled electronic maps or the old school paper maps.

Digital Maps 

Computerized maps have increased in popularity over the years.  There are advantages and disadvantages.  I have switched to almost completely computerized maps on my smart phone.  The ability to easily scale the image to match what I'm seeing and even flip the view when switching from the viewfinder to the eyepiece makes it so much easier to use.  Another nice thing is that digital maps show exact locations of moving objects, like the planets, asteroids and even comets.  You can even get the moon positions for shadow transits on Jupiter.

I also set up circles on the display to match the field of view of both my viewfinder (5.7°) and my wide angle eyepiece (1.37°) so it's easy to tell what will be visible.

There are some disadvantages.   You have to make sure your batteries are charged and you have enough for your session.   I always have a paper map handy just in case.  If your laptop or tablet is too big, you can't hold it next to you while viewing like you can a small paper map.   Larger phones and smaller tablets work well for this reason.

Also, you need to make your device safe for your night vision.  White light greatly reduces your night vision and should be avoided.  So for a laptop, you need rubylith film to cover the screen.  You also might need to tape over status lights and such.

On a tablet, you need to put the software into night mode.  But that's also not enough.  Some screens don't go dim enough, so I use a screen dimmer app as well.   Plus you need to make sure the buttons don't light up bright white.  And sometimes the keyboard or scroll bars will pop up bright white.   Some people just rubylith their tablet, but that makes it only dedicated for astronomy.

Stellarium:

A free computer-based star map software that is very popular.  Here's the blurb from their website:

Stellarium is a free open source planetarium for your computer. It shows a realistic sky in 3D, just like what you see with the naked eye, binoculars or a telescope.

Sky Chart / Cartes du Ciel

Another popular free computer-based star map.

SkySafari - App for both Android and Apple:

This has 3 different flavors.  Basic, Plus, and Pro.   For most users, Plus is a good balance and with over 30,000 DSOs will keep you busy for a very long.  If you have a very large scope or just want no compromises, Pro has about everything under the sun (and over!).

Sky Safari in night mode showing telescope controls

Sky Safari showing M8 region

Paper Maps:

TriAtlas:

The TriAtlas set of maps by José Ramón Torres and Casey Skelton are a free set of printable maps. There are actually 3 different map sets. Set A is a limited map and is about the equivalent of the Pocket Sky Atlas (see below). Set B is more detailed and set C (all 570 pages) is very detailed. It's nice that the maps reference each other, so it's easy to go back and forth. I have a set printed of A, B and the northern hemisphere part of C.

The following info was a great writeup provided to me by Alan from astronomyforum.net about the various paper mats.  Thanks!

Pocket Sky Atlas:

Stars to mag 7.6 with 1500 DSOs plotted. The pages are 6 x 9 inches, and it is very easily held in one hand. It has 26 charts with 4 close-up charts in the back for the Pleiades, central region of Orion, Virgo galaxy cluster, and the Large Magellanic Cloud. Its main drawback is its depth for those with large scopes or who observe in very dark skies. It is an excellent starter atlas, and one that I have used extensively despite its limitations. It presents black stars on a white background with the Milky Way and DSOs plotted in color.

Sky Atlas 2000 2nd Ed:

Stars to mag 8.5 with 2700 DSOs plotted. The unlaminated versions have 26 charts that are bi-fold and unfold to 21.5 x 16.5 inches. Obviously best to use with an observing table to take full advantage. It also contains 7 additional close-up/finder charts in the back forBarnard's Star, Pleiades, Proxima Centauri, North and South celestial poles, Virgo galaxy cluster, and central region of Orion. The laminated ones are not folded and are quite heavy. The difference between the desk and field versions is the desk is black stars/objects on a white sky and the field is white stars/objects on a black sky. The premise there is that it more closely approximates what you see in the sky. However, I used to have a laminated field version and I found I didn't like the white on black sky for use with my red light. Some prefer the white on black, but I simply found it more difficult to see the objects. I also did not care for the laminated version because I felt I was having to fight glare due to the lamination. It was also quite heavy to work with. I currently have the unlaminated Deluxe version. I like it because it has black stars on a white sky with the Milky Way and DSOs plotted in color in the same scheme as the PSA.

Uranometria:

Stars to mag 9.75 with 30,000 non-stellar objects plotted. It is a hard backed book and is heavy.
When laid open, it has 220 double page charts at 18 x 12 charts. It is quite comprehensive, but again, one needs a table on which to use it. It also has 29 close up charts for areas of particularly heavy congestion and they reach to almost mag 11. While it may be bulky, for the hard core DSO chaser with more aperture it is indispensable. I particularly like to use it for planning indoors, though I do take it out at times. As with all my atlases, I do try to protect the pages from dewing as best as I can by laying a towel over them on the table if dew is present.

Interstellarum:

A newer atlas that contains stars to mag 9.5 with almost 15,000 DSOs plotted. It uses black stars on a white sky with color for the DSOs. The big difference in how they code their objects is that it is based on visibility in a specific aperture. They break objects down based on observability in a 4, 8 or 12 inch scope in dark skies (typically mag 6.5 skies), and they use different color shading to indicate the smallest aperture (4, 8 or 12) that an object is visible in. Of course that is not a hard and fast rule as there are always variables associated with visibility. But it at least can give observers something to hang their hat on. It appears to be a very nice atlas, though not exactly cheap. It comes in two versions, the desk, which is printed on heavy paper (little less thickness than the PSA), which if properly taken care of should hold up well. Then they have a field version which is printed on a water resistant foil of some sort. Interestingly, the field edition is lighter in weight than the desk version as the material its printed on is thinner, yet water resistant. It is spiral bound and can be folded back on itself, but it is a bit awkward to hold in one hand at the scope. It contains 114 double page charts when laid open with 29 close up charts. The page size is approximately 11 x 11 inches.