johninderby

Was sunny five minutes ago. Now 🤬

You fotgot grey as in medium, dark or very dark. 😁

The sun peeps out now and then so maybe a brief look. 🤔

This may be of more use today. 😁 https://whatsthiscloud.com/cloud-identification/

Slight improvement in the forecast.

Showers here with sunny breaks until about 3:00 when it clouds over completely so might get a brief glimpse. 🙏🏼🙏🏼🙏🏼

As above velcro does have a limited lifespan if frequently unfastened but should be OK if left in place permanently. Personally I prefer a couple of tube rings with a handle fitted.

Yes the ES 32mm and 40mm in that series are 2” barrels. If you want a 40mm 1.25” eyepiece thay are available in several brands but in smaller fov. The TeleVue 40mm Plossl 1.25" is very nice eyepiece but only 43 degree.

Wonder how it compares to a Siebert 4.3” observatory eyepiece?

Looks like I may have to resort to this to view the transit.🤔 https://www.timeanddate.com/live/ Or this 😁

Looking more like I will have to resort to this to see the transit.🤔 https://www.timeanddate.com/live/ Or this 😁😁😁

Looks like an interesting little project for sometime this winter. Will keep you in mind if I need some projection material. 👍🏻 John

The 28mm Nirvanna is pretty good for low power viewing. https://www.microglobe.co.uk/ovl-nirvana-28mm-uwa-82-high-performance-eyepiece-p-9272.html The 16mm Nirvana would also come in handy for something in between.

Has anyone tried building a sun funnel? Looks like a simple project. 🤔 https://legacy.aas.org/files/resources/build_a_sun_funnel_v3.2.pdf

Ready but the weather forecast is looking a bit iffy for tomorrow. 🙁

Some info here including reduction in light when using binoviewers. https://starizona.com/tutorial/binocular-viewers/

Telesope Express gives these specs for the 300pds so I’d be surprised if your secondary is different. Aperture: 12” - 305mm Focal length: 1500 mm Focal ratio: f/4.9 Mirror: Parabolic primary mirror - substrate is Pyrex Secondary mirror: Diameter 70 mm minor axis

One point that I rarely see raised when discussing binoviewers or binoculars is that they aren’t suitable for everyone. In some people using them causes eye strain and they just aren’t comfortable to use. This has nothing to do with colimation etc but simply that some people have issues with vision convergence. Particularily if they have different levels of vision in each eye. One person may rave about how great binoviewing is while the next may find them worse than single eye viewing. Best thing is to try a few different ones to see if they suit you.

It was mentioned in a CloudyNights thread but no etails other than the results. https://www.cloudynights.com/topic/657636-black-30-the-new-blackest-black-paint/page-2

Sounds good although seems their claims are a little bit exaggerated. Any paint though will perform better on a rough or ribbed surface when light hits it at an angle. Here’s the results of comparitive tests in a lab.

Protostar flockboard is great but too expensive to import so I made my own version. Get some acetate sheet 600micron thick and make a sleeve that will fit inside the tube. Then put the self adhesive flocking onto the acetate sheet while it’s sitting flat on a table. No need to tape the seam in the sheet when you slide it into the tube. Get the proper flocking material that won’t shed fibres. Don’t use the high street flocking as it will shed fibres. https://www.firstlightoptics.com/misc/black-velour-telescope-flocking-material.html

The Nirvanna eyepieces are very good and 82 degress as well. Only 4mm, 7,mm and 16mm available but a bargain for performance almost as good as a Televue Nagler. https://www.harrisontelescopes.co.uk/cgi-bin/ss000001.pl?page=search&SS=nirvana-es+&PR=-1&TB=O&ACTION.x=0&ACTION.y=0&ACTION=Go!

Ouch ££££ Was just wondering if you had rubber tiles down. I bought some from Amazon for my shed recently. https://www.amazon.co.uk/Assemblemat®-Interlocking-Yoga-Exercise-Garage-protection-Playroom-Anti-fatigue-EVA-Foam-Rubber-Best/dp/B018VWPH2E/ref=sr_1_10?dchild=1&keywords=rubber+floor+tiles&qid=1573310871&sr=8-10

Louis de Broglie has a lot to answer for. 😁

Biscuit Dunking Physics http://www.abc.net.au/science/articles/2000/02/03/97177.htm In researching dunking it seems that Americans like dunking doughnuts. Don’t think dunking a cream filled one would be a good idea though. 😂