Have you any ideas to share?

[Second Time Around]

I've learned an awful lot from the forum, and thought it might be appropriate to share a couple of short ideas/tips I've had with the community.  They're not worth a topic in themselves, but hopefully it'll encourage others to post something similar here.

Firstly, I found myself often bumping into my observing chair in the dark.  Why on earth are they so often painted black?  Initially, I simply put a white carrier bag over the seat.  This worked, but I wanted something that was going to last longer.  I found the solution in a white shower cap, and tracked down an extra large one on Amazon.  This fitted beautifully and solved the problem. 

In fact it came in a pack of 2 for £10.99, and I used the second one with some cushion stuffing to make a comfy top for a telescopic stool I use with my small refractor.  Here's a link: https://www.amazon.co.uk/gp/product/B0796LRRF4/ref=ppx_yo_dt_b_search_asin_title?ie=UTF8&psc=1&fpw=alm 

 

 

Secondly, I use this 72mm f/6 refractor with a Quark for h-alpha solar viewing.  With the Quark's inbuilt 4.3x focal extender this gives a final focal ratio of f/26.   This isn't bad for seeing prominences, but for surface detail the recommended final focal ratio for the Quark is f/30 or preferably even longer.   This means a starting focal ratio of f/7+.  A common way of achieving this is by stopping down the aperture of the scope.  Unfortunately, like many others, my Altair refractor doesn't have a dew cap with a reducer.

I came up with the idea of using a rubber lens hood fitted over the end of the tube.  The rubber is flexible and stretches over the tube to give a tight fit.  In my case I needed an inside diameter of 88mm or a little less, to fit a filter size of 58 or 62mm.

A search on eBay turned up this one for £4.99 delivered: https://www.ebay.co.uk/itm/SCREW-ON-58MM-PROFESSIONAL-RUBBER-COLLAPSIBLE-LENS-HOOD-FOR-SLR-LENSES-QUALITY/191077958000?ssPageName=STRK%3AMEBIDX%3AIT&_trksid=p2057872.m2749.l2649  from photo-accessories-wales. This has an inside diameter of 85mm to fit 58mm filters.  The clear aperture is 54mm, so with a focal length of 432mm this gives a focal ratio of f/8 natively and f/34.4 with the Quark.

 

Edited December 11, 2020 by Second Time Around

[Paz]

Heres one from me that you might not hear often (maybe because it's obvious!), when walking around in the dark take your steps slowly and deliberately. You only have to have one bad slip and it could be the end of being able to observe.

I slipped in the dark and very nearly landed spine first on the edge of a concrete step once and in the time it took to hit the ground my brain managed to process the thought "...what an idiot, if I manage to get away with this I'll never be complacent in the dark again...". Luckily I got away with it that time.

[Moonshed]

After Christmas is out of the way I will be ordering a pair of red goggles. It means I will be able to put them on so I can pop indoors and grab a nice hot cup of tea without loosing my dark adapted eyesight. No more bumping into the tripod legs on my return.

Edited December 11, 2020 by Moonshed