Second Time Around

What scope was that in, Louis? If a reflector, was that with a coma corrector and if so which one? Thanks.

Louis, I agree that the APM zoom isn't small, but it's not huge either. However, I don't add a complete Barlow when I want to increase magnification, just the cell containing the lens. So it's barely bigger than the zoom itself. This is because, as mentioned above, adding a Barlow to the APM zoom increases the magnification more than normal. In fact I now have 5 different Barlows that I can use with just their cells, although I've yet to try the 2 newest.

Found my receipt too. The Omegon Redline was £116 including postage on 2nd Jan 2020. So a big increase since.

I also use sat24 that's the same as netweather. Both use infrared satellite pictures so, unlike visual pics, show cloud at night. Another similar but different site I find useful is https://zoom.earth/maps/satellite/ This also shows low cloud/fog.

Thanks, Don! Good spot! I see that Astromania is having it shipped direct from China, that hopefully will mean that postage is also low. Has anyone found it even cheaper? I said to my wife that the current Omegon price is a lot higher than I paid, that if I recall correctly was about £110 including VAT. However, that was just before Brexit.

1. Ernest in his bench tests measured the eye relief at a constant 17mm, i.e. about the same as a 25mm Plossl. For comparison he measured the Baader Mk IV to be 10-15mm, and the Svbony 3-8mm to be 6.5-9.5mm, both depending on the focal length. Incidentally, I didn't buy the Svbony 3-8mm because of the short eye relief. I prefer to Barlow my APM zoom, especially as Barlows somewhat increase the eye relief. 2. Whether it's a problem will depend on the amount of infocus of a given scope. There's no such problem with either my 72mm ED refractor nor my 10in OOUK Newtonian. I haven't tried it on my 4 inch achro yet. One thing to note is the amplification factor of Barlows varies from eyepiece to eyepiece according to the position of the field stop. With the APM zoom it's particularly increased. I have several Barlows including the Revelation in your signature. Here are the amplification factors I measured: As 1.25 inch cell only 1.97x As 2 inch cell only 1.77x I couldn't test the complete Barlow as the set screw was too long. I haven't got round to replacing it as I have other Barlows I can use when I want greater amplification.

Can't get rid of the sunglasses in the above thread. Any suggestions?

We repeatedly have comments on the forum dissing the cloud forecasts. However, some of you will remember that I recorded the accuracy of 6 (😎later eight) such forecasts every night for 17 months. See https://stargazerslounge.com/topic/376745-a-record-of-the-accuracy-of-my-local-cloud-forecasts/#comment-4081235) These showed 2 things: 1) the forecasts were correct roughly 2 nights out of 3 2) only 4% were completely wrong 3) there was no significant difference between any of the sites (including Clear Outside) So how do we account for the criticism not tying in with the data? I commented in that thread that it's human nature to remember the wrong forecasts more. In fact, there's a scientific term for this; it's called the Von Restorff Effect.

I bought the 22mm/70 Deg Omegon Redline. Everyone's different but I preferred it to the much more expensive 22mm Nagler. It's supposed to be not quite as sharp as the Nagler at the extreme edge, but the shape of my eye sockets means that I can't see the very edge of many wide angle eyepieces anyway. I also found the Redline very comfortable as well. A further advantage is, as Louis kindly pointed out to me some years ago, it can take a Dioptrx astigmatism corrector that I prefer to wearing glasses. It's currently £162 including VAT plus shipping from £6.90. Go to https://www.omegon.eu/eyepieces/omegon-redline-sw-22mm-eyepiece-2-/p,33239

I'm a great fan of zooms and have used 5. The best is the APM Super Zoom, that I found even better than the Baader. It has a constant 66 degree field of view. I haven't tried the very expensive Leica though. This is because it doesn't accept a Televue Dioptrx astigmatism corrector that I prefer to wearing glasses. Both the Baader and the APM accept a Dioptrx, although the eyecup of the Baader revolves when you zoom, making it fiddly. Neither have I tried the Svbony 3-8mm as there would be insufficient eye relief for me. Instead I prefer the APM plus a Barlow.

Another site with seeing forecasts: https://www.metcheck.com/HOBBIES/astronomy.asp It also shows transparency forecasts.

I mentioned tourism, that of course affects locals and the local economy.

Done.

You can add an inexpensive extension tube(s) between the eyepiece and Barlow. For instance Baader do an 18mm one, and each of these will add approximately 0.25x extra amplification. Go to https://www.firstlightoptics.com/adapters/baader-dt-4-1-31-8mm-nosepiece-extension-18mm-long.html

One thought is to combine an OOUK Dob base with another make of OTA. This is what I posted recently about the OOUK bases. "The bases are the best part of the OOUK Dobs. They're made of aluminium so are lighter than steel or plywood let alone particleboard. They also have a smaller footprint that enables them to be carried close to your body. Both of these features make them much easier to carry. Indeed, I can go up to a 10 inch OOUK Dob, but only an 8 inch with Chinese makes. The only mod I've done is adding a pair of kitchen door handles. OOUK make these bases to order to fit any Dob, not just their own. Expensive yes, but well worth it." A second idea is to buy the cheapest Starsense Explorer in the range that costs £189 and retrofit it to whatever scope(s) you end up with. I believe Ratlet here can provide a 3D printed adapter.