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Old 16-11-2014, 08:28 PM
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mental4astro (Alexander)

mental4astro is offline
Join Date: Jun 2008
Location: sydney, australia
Posts: 4,869
Thought I'd share some of my thoughts, experiences and new practical techniques I've adopted in the last couple of years. Some I've adopted from fellow astro nuts, others I've modified with experience, others have come about just from trial and error.

Observing from light polluted areas
While aperture is King, under urban skies this is not necessarily the case. In many instances it can actually be counterproductive. I've found that using big apertures also increases the effects of light pollution. These days, when I observe from my home in Sydney, I opt for smaller apertures, 4" to 12". I just don't bother with my 17.5" dob from home as the sky glow just overwhelms everything else. If anything, I tend to prefer my smallest of apertures and enjoy low power wide field viewing - light pollution has significant less affects. The comet Lovejoy inparticular showed me the 'power' of smaller apertures over large from urban areas. My 11X70 binos do well from home too. Otherwise I mainly focuse my home-based viewing to the Moon and planets.

Eyepieces and dew
Little ruins a good night's viewing like dew. My original counter-measure to dew was to attach a heating strip around the eyepiece at the focuser. In the end this really did not work for several reasons: a, focuser was very cold, so any heat the dew heater could put into the EP, the metal focuser sucked out straight away, and dew wasn't challenged, b, the sheer bulk of some EPs, like my 1kg 30mm toe crusher, there is no way a dew heating strip could do to deliver any substantial heat into a cold EP to prevent dewing.

The solution I read about by chance one day - heated eyepiece case. If the heat is in the eyepiece from the start, the heating strip is then effective in maintaining a warmer situation for the EP, rather than a futile attempt to introduce heat.

MY solution however is a take on the heated eyepiece case - a hot water bottle in a cosy! I put the hot water bottle inside my eyepiece case, and a couple of towels (that I already have in the car from protecting some gear during transport) over the lot for insulation. This gives me at least 6 hours of heat during very cold nights. A thermos of hot water for a midnight exchange sees me through to dawn.

You might prefer to make an electrically heated eyepiece case. The thing is to have the heat in the eyepiece from the start.

Patience, persistence and adaptability
Our opportunity to use a scope, leaving life and work aside, is pretty much determined by the weather. Even if the sky is clear, conditions can range from poor (all too often) to cracker-jack good (not nearly often enough). Transparency if poor ruins our ability to see galaxies. Poor seeing limits how high in magnification we can pump things to. But, even with difficult conditions, changing our aims for the night, or limiting magnification, we can still make a poor night a memorable one. Taking a couple of scopes or packing your binos with your scope, will allow more versatility in observing capacity as each scope has its own set of strengths and weaknesses.

These are some thoughts that hopefully go to inspire some ideas for you. I'll try to add some more soon.

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