Mr niall

Don't use 3200. The best ISO for the 600D is definitely 800 ISO. http://dslr-astrophotography.com/iso-values-canon-cameras/

Sorry Video won't load, but no - it's definitely not a quasar. Bearing in mind the most powerful optical telescopes on earth cannot resolve the closest stars to us (4 light years the Centauri group) as anything more than point sources of light; then that hopefully conceptualises why you wont see a spinning quasar in your 4 inch Mak, but from what you describe I can see where you are coming from. It would be pretty cool if it were the case. I think what you are describing is atmospheric turbulence. The stars do wobble about a fair bit, especially lower one's nearer the horizon. If you imagine the mirage's and heatwaves that you get in the distance on really hot days - well that's kind of what happens in the atmosphere too. And a telescope has a lot of atmosphere to look through. All normal.

If my maths is right I think you've photographed an area about 190 miles across the diagonal from corner to corner.

No... you definitely haven't. You'd need a telescope in excess of 75 metres eg 750 times bigger than your Nexstar 4 to be able to see it. I love your enthusiasm but it might be worth researching what your Nexstar 4SE is actually capable of resolving (in the same way it can't see the rings of Uranus). Nice picture though.

I've got a pair of Celestron Skymaster 15x70s that I'm about to sell but I haven't got round to it yet. I've got the Opticron heavy duty tripod adapter too. I don't think I'd want much for them - probably about £35 (and a couple of quid for postage)? If they'd be of interest to you let me know. Just a thought, no probs if not I'll just stick them in the classifieds. I love them but really wanted something hand held so bought a pair of 10x50s, definitely noticed the drop in aperture but they're a bit easier handheld. It was my intention to do the whole messier list from my back garden but when I realised I could only just about make it M51 and M101 with a 12" dob then... well it kind of put a stop to that though. Hoovered up at least 30 or 40 though even from light polluted skies. M81 and 82 were a nice surprise.

Boom...

Yeah - I debated using a 130pds on one for some visual grab and go but FLO advised against it so 150 is probably way out. It's code for "don't do it!!" 😉 it means as you get close to the limits of what a mount can theoretically hold, the pleasure of using that mount drops dramatically. The whole thing becomes a bit wobbly and bouncy and "feeling like it might let go even though you know it shouldn't". Always best to go belt and braces, 2/3 of max weight of the mount including tube rings and accessories etc is a sensible maximum. If you've picked up a 150PDS with coma corrector then, well, you've bought an astrophotography oriented camera. You'd be well advised to think about getting a HEQ5 to plonk it on. A normal EQ5 would work too.

If you go to binocularsky.com you'll find everything you need there. Steve does a monthly newsletter as well with all the best targets for the month.

Hello all Can't believe I'm asking this question three years down the road but chances are my stupidity is the problem not the scope. I've moved from a 12" dob to a 60mm refractor. Its lots of fun. However I am struggling to focus at high powers. Or am I? I'm using a 60/900 so with a 10mm (off brand plossl) eyepiece I'm getting 90x with an exit pupil of 0.7mm give or take so I'm probably not going to go much higher than that. Jupiter and Saturn seem fine (well I say fine, they're a bit smushy and at this time of year with them being so low its difficult to know if "best focus is really in focus", Moon seems fine, great actually - but I'm struggling at achieve focus on point sources - like Vega or Deneb for example. I'm getting near focus and then diffraction rings start appearing or the whole "star surrounded by a dancing strobe light" type sensation. Racking the focus in and out reveals a nice array of diffraction rings that my limited knowledge can establish are roughly concentric and look ok. I'd come to the conclusion that I had a spherical aberration that was limiting my experience in what (lets be honest) is a very budget scope. Certainly the criteria for spherical aberration of "fine at low powers, won't focus at high powers" applies to me in this case. But now I'm wondering if what I'm actually seeing is the Airy Disk and the scope is fine. Having a 12" dob I never really got anywhere near 1mm exit pupil on point sources (why bother?) so I'm wondering if its just something I've never encountered before; especially considering the generally rubbish atmospheric conditions of the last few days. Could that be it? Is this a typical (not feeling like you can focus to a point on bright stars at low exit pupils) experience? Or is it just indicative of a poor scope? Many thanks Niall

I googled it - it looks like you'd need a 1 metre telescope to be able to detect them: https://britastro.org/node/8591 But I agree - it does look exactly how you'd imagine they'd look can totally see why you thought you'd got them. Niall

Can I ask if your 102 has the collimatable back? It looks a little like SW do two versions of the 102, one that is colimatable and one that isn't (not that it matters massively) if you compare the AZGTI version with the OTA only version.

Hello there Lots of people will give you opinions about what would suit your needs - but you are right in that dobs are visual only really with very limited future upgrade potential. However if you are looking for a visual only scope with the potential to upgrade later I would personally try to steer you away from the 150p on an EQ. Logically you are right in that it "ticks the boxes" but the problem I found was that starting off in astronomy with a manually controlled EQ mount was an absolute nightmare and a very frustrating experience. You'd be better going straight to the GOTO option I think if you wanted to do that (budget allowing).They're great once you've found your object but scanning the skies looking for something can be an exceptionally frustrating experience as they don't have the up/down/left/right movement that a standard alt/az mount has. It may suit you better to consider getting your big dob now - and then re-visiting whether you want to move into astrophotography further down the line; possibly with the investment in other kit. They're quite different disciplines and it's really difficult to get a "one scope for all" type setup that doesn't compromise you on something. But its quite subjective and others may disagree. As a note - Orion and Skywatcher are the same company basically. Once you start shopping around you'll notice that many scopes look suspiciously similar; Orion focus mainly on the US market that's all; so its cheaper to buy Orion in the US and Skywatcher in the UK. The Orion XT series and the Skywatcher Skyliner series are the same thing.

m31, perseus double cluster and the coathanger are really visible good work.

I'm struggling to reach focus on both my 60/700 and 60/900. Witha 10mm eyepiece I'm getting 70x and 90x respectively. If this is too much for the scope then that's no problem - but I'm used to bigger apertures so was slightly surprised that sharp focus isn't really achievable. Whether I'm using the bundled 10mm MA or a slightly better 10mm Plossl I'm experiencing a situation where it approaches focus then starts to drift away again as it gets close, usually with a fuzzy airy disk or - on planets, like a smush smear almost around the edges. Have replaced the diagonal but not experienced an improvement. I'll admit the diffraction test confused me a little: if I reach focus and keep going I get a series of perfect sharply defined concentric circles, however when I come back from focus and keep unwinding I don't really get anything but a big old circle, it's such a different experience on both sides of focus its really thrown me. This has been repeated on several stars over several nights. Also - anything over 100x gives some fairly serious CA which is a big surprise for long focal length scopes. But I appreciate that I'm pushing the envelope a bit. Any insight appreciated.

The case continues.... might get a good sequel out of this. “Iridium 69, wrongly convicted of a crime it didn’t commit, escaped to the Los Angeles underground. Now it survives as...” oh wait that’s already been done.

Yeah It could have been, I did some more investigating and they seem to like a good old flare so if you think it matches up it may have been one of them too. Iridium pass was 10pm

I just had some fun recreating the scene of the crime on Stellarium. Initial forensic results indicate the following perpetrators were in the vicinity at the time of the alleged offence: STSAT 2 and STSAT 3 NOSS 8 However our current prime suspect based on the modus operandii and their history of bright flaring in and around astrophoto's is clearly: Which is interesting as I thought they'd switched them all off and decommissioned them but I guess they must still be up there living a life of crime. Edit: I Just checked the Satflare forum and it looks like for some reason I69 is indeed still up there causing trouble. Take'em away boys! 👮‍♀️👨‍⚖️🚓

Thats very clever 👍

Just noticed that M29, M27 and M71 line up almost perfectly; can't believe I've never spotted that before!

25 x 150 secs lights 12 x 150 secs darks Canon 1300d on homemade tracker (Gary Seroniks hinge tracker based) Canon 50mm lens f2.8 DSS, TIFF Liberator, GiMP.

I suppose, and then the kids could use the optics as mini frisbees or something. But it might tarnish my whole "astronomy on an absolute budget" ethos. I don't think "astronomy on an absolute budget using a Takahashi sellotaped to an AZ2 cos I refuse to waste money on tube rings" really has the same ring to it... Seriously though, I remember losing the top cap off my 7-21 zoom once. I found it eventually although I have no idea how it ended up where it ended up, but I remember looking at it sitting on the shelf without the top cap on it and being really worried - like I was expecting it to explode or something?! But there is little in life more frustrating than losing a bit of something, it kind of makes the whole thing feel a little redundant and tarnishes your enjoyment which is ridiculous when you look at it objectively but it still seems to be true. In reality I guess caps and plugs are a bit like the "glass fragile" stickers they put on boxes just before they chuck them in a van and send them half way across the world... I'm sure that sticker makes all the difference 🤔 (I still wouldn't post without one though!!). Hope you find it (that tenner is still on offer of you don't 😉)

That's terrible news. If it doesn't work out I'll give you a tenner for the scope - provided you pay postage of course (although I'm not sure what I'd do with it without that metal plug, maybe use it as a guidescope or take the lens out and use it to store bits and bobs; or maybe turn it into a decorative planter) 🤔 I know that won't ease the pain but hopefully it'll help to know you've got a course of action with a positive outcome if you don't find the holder plug.

Hello there I was wondering, when it comes to solar projection, how do you determine how far away to put your projection screen from your eyepiece? Or does it matter? I mean - what I'm assuming is that the projected image just gets bigger and bigger the further away that you put your projection screen? Is that right? Am I right in further assuming that the further away you put the screen - and therefore the bigger the image - the less definition you see? So say for example I was projecting a lovely sunspot (fat chance at the moment!) onto a surface, would there be a point where the sunspot would go from having nicely designed edges to being a vague greyish blob on the projection screen as you moved it away and it got bigger and bigger? Does aperture therefore make a difference? Many thanks

I was at a reasonably dark sky over the weekend (bortle 4) and easily - easily - picked out M13 and M27 in my 60/700 refractor. In light polluted area's globular clusters are probably the easiest to pick out, followed closely by open clusters, then planetary nebula. Galaxies are the most challenging but you should still be able to see M31 / M81 / M82 without too much difficulty. Lots of fun stuff to be seen with your scope don't worry!

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