Society for Popular Astronomy

I saw an all sky halo display in Finland about 1980. It was the most beautiful sight I have ever seen observing the sky. There were numerous and some very rare forms. Complete horizontal arc. Forms opposite the Sun. There were two suns, one false. There was probably a third hidden behind a building ...

My old 123mm f/5 refractor goes from 16x with an old Kodak 38mm Eyepiece. 4.7 degree field. The drawtube is 3 inches diameter. The telescope has no finder as it doesn't need one. There are modern 3 inch eyepieces, maybe also bigger. The Yerkes refractor drawtube may be 5 inch diameter. The 123mm ref...

Although Plossls are now plentiful and have been used in military optics regularly, they were not so common in the 1950s and 1960s as astro eyepieces. Orthoscopics and Kelners were the normal better eyepieces available. I still use the orthos and Kelners more than Plossls. As well as Erfles, which w...

Wow.

Regards,
David

George Alcock's large binocular was a Schneider 25x105 with 45 degree inclined eyepieces. These had triplet, probably uncoated, objectives. Unfortunately when these objectives were distributed to the U.K. the components got separated. They were bought by different dealers. Some bright spark commerci...

The view of Mars through Horace Dall's closed attic window using his world class 8 inch Maksutov at 400x was unbelievable. It was the equal of my 12.5inch Dall Kirkham in my garden. His camera obscura from indoors provided daytime views that were just spectacular. His photos of a church gutter at 17...

I would take great care before becoming a solar observer.
One mistake can damage eyesight.

I suggest observing Mars and other objects first to build up experience.

Regards,
David

Saw Mars as a disc at 25x in Opticron MM2 52mm spotting scope.
No detail seen.
2020 Sept 17 02.10UT.

Hand held against window glass.

Regards,
David

The finder should be aligned with the scope, say on Polaris.

The scope with the 10mm eyepiece, or first with the 25mm eyepiece if Polaris is not in scope field.

Centre of finder with centre of scope view.

Regards,
David

Hi Nigel, For planets in daytime without optical aid it is essential to know the position exactly. Central vision is used and this is less than 2 degrees Also the faint planet must be exactly in focus with glasses if necessary, but I did not need these when younger. The air must be clean and transpa...

Once I saw Mars with unaided eyes in daylight at magnitude minus 0.9 by placing it on top of tree. I have seen Jupiter many times in daylight with unaided eyes. Mars is not particularly difficult in daylight with a 10x25 binocular. I still have not seen Mercury in daylight without optical aid, altho...

Hi Simon, I would suggest a 6mm or 6.3mm eyepiece as The Barlow means removing the eyepiece, fitting the Barlow and putting the eyepiece back. As the scope is undriven this is fiddly. The 25mm eyepiece gives an exit pupil of 5.2mm. If you have astigmatism this might be the reason for the headache. T...

If a Barlow isn't included then a 6mm eyepiece gives 200x and a 7mm eyepiece 170x. It depends on finances. Skywatcher offers different eyepieces as does Explorer Scientific and others. With a Dobsonian, wide field eyepieces are easier at high power to allow longer observing times. But narrower field...

Assuming the focal length is about 1200mm, then the 10mm eyepiece gives 120x. This should show some detail. The 25mm is too low power to see detail at 50x. If a 2x Barlow lens is included it would give about 240x with the 10mm eyepiece. I would try that on a steady night. The cooling time depends on...

The street light shouldn't make a difference. Was the telescope properly in focus? What magnification/eyepiece was used? Probably 150x should be used, with 200x in better conditions. There should be a white pole cap and markings on the disc. However, dust storms on Mars can obscure everything. Even ...