Ags

Yes but that that bounces you some upside-down alternative app store to actually do the download. I'd never heard of Aptoide before and didn't appreciate having to trust it and grant it broad system permissions just to get a simple app.

Image doesn't look right. Here is a reprocess on my mobile phone. Looks like Gimp PNGs turn dark when comoressed in WhatsApp and SGL.

I am down to just one scope at the moment, my C6, and only one mount that can carry it, my AZ-GTi. I thought I would retract the legs on the Berlebach Report tripod slightly as I was only doing photography. While trying to loosen a leg clamp, there was a crack and now the knob just turns freely without loosening or tightening the clamp. I hope Berlebach can send me a replacement and explain to me how to get the broken knob off... Once set up outside I discovered the Synscan Pro app does not work with the latest version of Android. And the Synscan app is no longer available from the Android store but only from some well dodgy source. Once that was solved - AZ-GTi batteries flat. The power tank worked instead but I suspect it is dieing, it always shows the Needs Charging light. But at least everything was now powered, connected and ready for imaging. I figured the skies would be dark enough by midnight, but it turns out high haze was making the midnight sky an annoying shade of (literally) white. By now my enthusiasm was evaporating, but I decided to shoot a quick sequence of M57 as a record of the evening. Collimation was out but I thought I would leave it till next time as I have not yet fitted Bob's Knobs and didn't want to wake the household rootling around under the stairs for a screwdriver. (When I got back in, I saw I had actually fitted Bob's Knobs months ago and clean forgotten! I am not the sharpest brick in the woodpile at 1AM...). So here it is - only half an hour exposure, no darks or flats, intervening thin cloud and messed up collimation.

I am not explaining myself well. I am not comparing the visual channel to the ALMA channel which benefits from massively more aperture. I am comparing the visual channel with itself - it is so blocky with such stark jumps in brightness between adjacent pixels, I just seems to me they could have got away with smaller pixels.

Gorgeous!

That agrees with what I see in the image, but the visible light channel looks really undersampled...

I do like a good APOD and today's is an amazing close in view of a planetary system being formed, combining visual and IR light. https://apod.nasa.gov/apod/ap210622.html The star HD 163296 is an A1V star about 330 light years away.. That dust ring looks about 200 AU across which means that it is 2 arcseconds wide. Pretty sharp optics from ALMA! Also the polar jets imaged in visible light - it seems to me to be undersampled - I wonder how big the pixels were?

But then you are spending over 400 euros to buy a barely acceptable telescope (look at the focuser)? And anyone buying that thing is almost guaranteed to NOT have a selection of mounts to choose from.

But it does have free delivery!

Best astophotography telescope?

Been plugging in star descriptions all weekend - adding textual finding instructions and general descriptions - and the odd factoid when I have one. I managed to get through 30 so far this weekend, a long way to go, especially as I keep thinking of new binaries to add!

All roads lead to spending more money... I am thinking of saving my pocket money for one of these: https://www.teleskop-express.de/shop/product_info.php/info/p4964_TS-Optics-ED-APO-102-mm-f-7-Refraktor-mit-2-5--R-P-Okularauszug.html https://www.teleskop-express.de/shop/product_info.php/info/p1151_TS-Optics-70-mm-f-6-ED-APO---Reiserefraktor-fuer-Beobachtung-und-Fotografie.html I am thinking the 70 mm might give more charming views of doubles and would be great for travel and photography, but the 102 mm would be able to replace my Skymax 102 and would let me get up to around 100x on planets (I am restricted to exit pupils of at least 1 mm). Probably I need both, but couldn't justify that many telescopes!

Yes it is. Works very well! This picture is slightly incomplete as I had not yet attached the 1kg counterweight. It is perhaps not strictly necessary but I feel it reduces strain on the AZ-GTi.

Had a quiet evening working on the spectral class / magnitude key.

Every once in a while my ST80 does this and I start shopping for ED doublets...

I was amazed by the beauty of the views given it was just a humble ST80 and Plossl.

I'll double check next time I have it out, but even perfect collimation seems to leave a little residual splodginess. The SCT never quite matches the cleanness of the views in my Skymax 102.

My main telescope is currently set up for imaging, so last night I ended up outside with an ST80 attached to a travel head on a photo tripod. The cheap diagonal was somehow occupied by a Revelation achro 2x barlow and 20mm plossl. I had no plans to do observing last night, but a draft of my book "Discovering Double Stars" had arrived and I wanted to test it under some real stars. There weren't many stars though, with midnight twilight and city lights I could only see the brightest star in Cepheus, so fourth magnitude and fainter stars were whited out. In brief the book worked well, and was easily read by red light torch. The star patterns easily guided me to doubles I had never seen before, so of course I was really pleased. But what will stick in my mind are the doubles, all viewed at 40x. In the refractor they were such perfect pinpoints compared to the less precise splots in my SCT. Zeta and Beta Cygni were delightful, and the colors in Delta Cephei were gorgeous! I was surprised I could split Xi Cephei at such a low magnification.

Once I have finished the writing and testing, I will make the PDF freely available and it will have a link to lulu.com where you can print a copy. Or you can just print out the pages you need at home, or open the pdf on your phone.

Received the latest draft copy of the book I am working on. The cover picture needs to be replaced as I can't contact the creator. If anyone knows any cool double star pics, let me know! This version of the diagrams passed the red light torch test, so now I can just focus on writing.

@Tiny Clanger The AZT6 is pretty nice and certainly very small and light, and also quite visually appealing. The only drawback is the clutches are a bit annoying - hard to make them fully engage and lots of turning involved. Great for airline travel. Taking on board the concerns about 6 - 7 kg load, I can get the load down to 5.5 kg if needed (C6 = 3.3 kg; RACI50+RDF = 1 kg; Diagonal = 0.2 kg; Eyepiece = 0.2 kg; Dew shield = 0.5 kg; 0.63 Reducer = 0.2 kg). Also I think it might be better if i get the AZ5 first, rather than trying to swap my Castor for one.

Good to hear weight is OK, Heather. Do you know if the AZ5 can cope with the tube diameter of the C6? How do you go about using it with those tiny clutches?

But apparently the user manual for AZ5 states 9kg, depending on tripod?

Currently I use my C6 on a Berlebach Castor at night and an ST80 and Herschel Wedge on an AZT6 by day. I also have an AZ-GTi, but I only ever seem to use that for imaging. The idea of the Berlebach Castor was to mount the C6 alongside an ST80 which would act as a superfinder for the bigger scope. But now I have a good 50mm finder scope and it seems to work even better with its wider field and correct orientation. So no need for the Castor, and I can keep the ST80 permanently configured as a solar scope. "Permanently configured" is a good thing, as I am one of those muddle-headed people that can get confused about just about anything, so excluding the possibility of putting the wrong diagonal on the scope greatly reduces the chance of me burning a hole in the back of my skull! One thing the Castor lacks is slow motion controls and it also requires perfect scope balance. I am thinking that the AZ5 would be a slightly more forgiving in the balance department and obviously provide slo-mo. So my questions... Is the C6 too big for an AZ5? Do you have to keep engaging and disengaging the AZ5 clutches to slew about? Why are the AZ5 clutches so tiny and is there a replacement? In terms of load, the total weight might get to 6.3 kg (C6 = 3.3 kg; RACI50+RDF = 1 kg; Turret+Diagonal = 0.4 kg; Eyepieces = 0.9 kg; Dew shield = 0.5 kg; 0.63 Reducer = 0.2 kg). The turret makes balance weird as there is a big load off the scope axis, made worse by the big finder, but on the other hand means that there is no mid-session rebalancing. To keep the load symmetrical I could strap on a 0.5 kg counterweight around the dew shield so that pushes total load to 6.9 kg. Is that too much for an AZ5? I must add the tripod is a short Berlebach unit that is as solid as a rock.

This isn't Top Gear, it's Top Astro Gear! Brilliant stuff, should be on TV.