Finder apps...

[Ilmenite (Nick)]

I am fairly new to astronomy and want to maximise observation time. My scope is manual other than a clock drive and I want to find an easy way to get close to targets i.e. Within about 2deg so I can then zoom in using eyepieces. A search reveals several different possibilities
1) Skeye
2) clinometer and compass
I have an older Android phone which can be strapped onto the scope to give readouts of RA DEC or Alt Az.
Would anyone care to share their views on this method?

[dimithri86 (Dimithri)]

Hi,

I use rubber band to attach my phone to the finder scope of my dob. A crude diagram below, if you dont understand it, I will draw a better picture. The phone and the finderscope arent doing anything together, its just a simple place to mount a phone. Then I open Skeye (I have the pro version, but i think simple version can do this too) Find a bright star in dob, and then click indirect mode on app, and then tell it what I am looking at. Repeat for a few more bright stars. And now I use it as a push-to guidance system. Find a object in the search menu and it till tell you how to push it, or push it and it will tell you what you are looking at. Sometimes it works quite well...sometimes I need to jiggle the scope around a bit.

I do sometimes get strange magnetic field warnings, probably due to the fact that is the touching my metal finderscope. I intended to mount it the scope body using a plastic car phone holder, but never got around to it.

O=====o <= look through here to use finder
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look at phone from here

[janoskiss (Steve H)]

Sky charts and star atlases printed on paper can still be more effective than computer/tablet/phone based systems.

I recommend a red head torch, the Night Sky Planisphere by David Chandler, the Southern Sky Guide (SSG) by Ellyard & Tirion, and a pair of 7-10x, 40-50mm binoculars.

You can locate dimmer/deeper objects in your planetarium program or on more detailed charts. Then mark it in pencil in your SSG and star-hop your way to it using naked eye and binoculars.

I find the star-hopping way more intimate (i.e., me and the cosmos) and exciting.

If you just want to point your scope at a chosen target ASAP then digital setting circles are what you need. I tried the smartphone method but the magnetic field sensor always gets it wrong or gets confused. (Maybe with a more expensive phone it's not so bad???)

[julianh72 (Julian)]

I find that SkEye works surprisingly well, especially if you can find a way to mount your phone on your telescope some distance off any steel (such as the tube and mount). If you have an aluminium or carbon fibre OTA, you can probably just strap the phone to the OTA; otherwise, one of those "Gorillia Pod" flexible tripods can work well. I mount mine a variety of ways, and while I occasionally get warnings about "strange magnetic fields", it never seems to upset the accuracy much (especially while you are working within one quadrant of the night sky).

SkEye's special trick is that it works in "indirect" mode so you don't need to align the phone with the telescope, you just need to fix it to the telescope. Unlike apps such as SkySafari and Google Sky Map, which give you a virtual view "through" the phone, SkEye allows you to tell it where the telescope is pointing when you start a viewing session, and then it tracks differential telescope movements from that initial calibrated alignment. You may need to do a new alignment when you move to a different part of the sky, but for me, it generally works fine on a single alignment over fairly extended periods within a quadrant or more of the night sky.

[Regulus (Trevor)]

Skyeye is good, and as long as your phone has gyroscope, compass etc then it will get you close.

Trev