7. Astro navigation basics  

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    How do I find my way around the Sky? 
    Shortest and simplest answer, get an Android/iPhone phone or tablet, preferably with cellular support and then install Google Sky, Apple Sky or Celestron Sky. For me, Google Sky is a simple strait forward guide, how to find my way around in the sky. 
    The earlier mentioned free star atlases, is also a good help, worth downloading. If you chosen the computerized telescope mount option, well, such tools is still an invaluable help planning the night's work. Sure the GPS and the sensors in the phones/tables at times play up, showing everything in the wrong direction, but resetting the app usually helps. 
    Most of us also live so we have a "preferred" direction of view field, rest limited by trees, houses, background light or other obstacles. Concentrate G-Sky at this visual area, see what's visible "now" or to be later during the night. 
    You can start already when still light, just "look" 3-4 hours "into the future", by turning the devise to the east and down (in Aussie-land and others downunder, the opposit). Turning your phone/tablet like that, will show what we will have in the viewing field some 3-4 hours later. Learn what's in this area with the app, then use tools like Sky-map.org or Stellarium to do detail planning. 
    When having a general idea, what to get in the viewing field later on, Sky-map then can give us an idea of what the big guys, running their Kecks, Subaru, ESA VLT or Hubble sees and we're not to expect to, but to strive for ;-). 
    By clicking on an object in Sky-map, we get some trivia about it, as well as close ups. Sky-map help us recognize object in our photos, us able to zoom in and out to see the area better. Sometimes I take a screen shot of Sky-map, import it to GIMP and overlay it to my own pictures, scaling it, to identify an unclear object. A club member in my astro club photographed a 7 billion distant quasar, me verifying it as such, this way. 
    Wikipedia is also a good source. They have easy accessible info from several star catalogues. All Messier objects and a lot of the more visible IC and NGC star objects have wiki pages, often with a good photo to compare with. 
    If having a manual mount, when we found what to look at, we identify some strong stars on the sky around the object. We can use that to zero in on our target for the evening, to narrow the search area. Called star-hopping, we can direct our scope or the tele lens at non-visible objects. 
    Even if working with my mount and tele lens or my current main scope, a Skywatcher Evostar 80ED, neither having a spotter scope attached, as most telescope do have; then I go on maximum ISO, take a step back, use the remote, shoot a single frame and look at the result on the camera screen. Do I recognize something on the camera screen? In which direction do I need to adjust the telescope/lens to? 
    This is the weak point with digital cameras like my Nex, we have only a light weak screen to look at, we seldom see what we'r aiming at. 
    Use simple techniques like these to solve the navigation, we can always delete that extra photo. Be methodical and after a while we start to recognize stuff up there, allowing for even quicker navigation and alignment. 
    So; plan, identify surroundings, check and zero in ...... and shoot your target as many time as possible ;-) 
    Now, some about the tripod and mount (AltAz style!). 
    First, place the tripod so the tripod North indicator [or the intended north leg] is due north, not 3-5 degree off, but due north, the tube or lens horisontal and flush to it. Use a compass, is the telescope tube or the lens really pointing exactly north. Be thorough, use 5 min extra, for it gives us much better tracking. 
    Also, if we are to use the same observation spot over again, make some distinct markings for the tripod legs, these always placed in the same position. One leg pointing north, the other two on the east-west baseline. Always the same and as exact as possible. 
    If you went for that computerized mount, there is a last thing, I mentioned in an other article. Many is complaining about tracking with this type of AltAz mounts. 
    What I found was, during alignment of the mount, when aligning with two aligning stars, marking these in the mount computer. If I choose two stars around 19:00 and 23:30 in the evening; if these being some 45 degrees on each side of my south meridian line (compass south), the stars also being around 45-65 degrees up from the horizon, I get far more stable tracking. 
    Unfortunately, all stars is not equal, Rasalhauge and Markab or Enif as well as Betelgeuse and Hamal or Denebola gives perfect results, while a combination of Aldebaran and Procyon is a disaster. I this season also found out, that skiping summer time conversion, running winter time year around, was beneficiary. Sure, I need to count back one hour, but easy learned. 
    All this, as mentioned, allowing regularly for up to 30 sec exposures with my AltAz mount. I am sure that if the same with a EQ wedged mount, 1-2 minutes exposures should be possible. 
    So, there you are. This was a simple newbie astro photo crash course, how to take acceptable beginners photos. As said before, find a place photograph and share the result with us.