rnobleeddy

Having played with a few random old and new lenses, definitely do some research before buying. All lenses are not equal, and the cheaper zoom lenses that come with DSLRs have been pretty awful in my experience. On the flip side, some older prime lenses have performed well. If buying new, there are some threads here that cover some common good choices, like some of the Samyang prime lenses.

Thinking of consolidating my kit, for a number of reasons; I haven't really taken to imaging whilst travelling (or don't travel enough), and there's not enough clear nights to justify trying to keep 4 OTAs in rotation! I don't have an obsy (yet) so setup time is a consideration. My most successful OTA has been my 130PDS - I built a shelf that I can install all the kit on, and so I can be up and running in 10 minutes from scratch. Other main kit is an EQ6 that I leave in the garden, a Canon modded DSLR and a QHY163 mono camera with FW + the usual 7 filters. So getting to the main question - what do people consider a good upgrade to the 130PDS? I'd like a similar/slightly shorter focal length, and nothing too bulky to make setup difficult. My guess is that a 100-120mm APO refractor would be a good bet - would people suggest that this would provide a decent step up? If so, is there much variation in imaging quality between the brands/designs - I know that a triplet is optimal, but I've seen good results from the ED doublets? Obviously, I don't need to spend the cash I get from selling my unused kit on more gear, so just sticking with what I've got is also an option.

I personally love KStars/Indi/Ekos. I find the interface much easier than anything I've seen on Windows. I'm not sure I fully understand this thread, but if you just want a single Windows laptop connected to your kit, I guess NINA or APT is a better idea? I've used a VM before, but for £50, and as long as you can get a reliable network connection, I can't see any reason not to use a Pi as the INDI server, even if you sit next to it with a windows laptop.

A random Astrobiscuit video is the reason I got in to astronomy. Obviously his videos hide a lot of the complexity, but that means they're also a good watch, and IMHO, probably the best astronomy videos on Youtube.

I don't actually know who this dealer is, but it may well be the person who's bought the most items from me on ABS! I tend to price items at 2/3 of the new price and don't care who buys them. If you're trying to help out a newbie by offering gear cheaper, then a first come first served model may not be best? I'm amazed anyone can make a living doing this, but I can't see any issue with it, especially if they're generally open about it.

It probably depends on your eye for detail. It will certainly hold it, but I'd imagine there'll be tilt going on. I have similar cam + FW (no OAG) and I'm happy with how well it works. It's pretty common to add a third screw to the focuser to help hold the camera. I guess the OAG isn't really needed given the FL of the 130PDS, but if you have it, it makes sense to use it - all this is adding is presumably a very light guide camera?

I guess from my experience, there's a lot more to go wrong during acquisition, but I'd also argue that processing is quite a lot more involved. I'm not aware of any free/cheap software that makes this easy?

Awesome stuff. I picked up an F/4.5 300mm Photosniper lens on ebay (tair-3-phs) a while back and just got it prepared for the next clear night. My previous attempts with vintage lens always lead to disappointment in the end but I have high hopes for this one!

One more for indi/Ekos. I've used NINA too, but I find Ekos more intuitive.

Thanks. I got pretty nasty results with the flattener initially. Part of this was my electronic focuser had some play in it, so the auto focus routine led to bad results. However, what also let me down was making the assumption that this would have the same tolerance as the Newtonian coma corrector I use, which appears to have a 1-2mm region which produce solid results. Based on what I experienced so far, the 0.79x flattener I have will need to be adjusted much more accurately!

After using a Newtonian for the last year, I finally got around to having a go with a 60mm APO refractor I bought 2nd hand last year. It looks undamaged, but I'm having a lot of issues getting acceptable star shapes. I went back to basics and removed the reducer/flattener, and so wondering if anyone can suggest if these results are normal for a refractor with no corrector? These are screen grabs of the data at full size. FL is 350mm and sensor is a 4/3 mono CMOS with a luminance filter. Short exposures (I think 10s) with the mount tracking. I only captured 2 corners + the center, but the other corners show the same pattern, with the stars (for want of a better word) "flaring" out from the centre. The effect reduces as you go towards the middle and appears to be symmetric around the center. I'm hoping that either looks normal or if not, perhaps it's obvious what the issue is? My mono camera + FW is heavy so there could be an issue with tilt, but I don't see how this would produce this pattern? Similarly, it's a doublet air spaced apo (photoline 60mm) so whilst color correction may not be perfect, I can't imagine this is related to that. Top left Approx central Bottom right Bottom

Thanks. I think I've jumped to causation when I really just observed correlation! I'm using a 9x50mm finders converted to a guidescope with 120MC/224MC - two separate setups with similar guide scopes give the same guide numbers with the correct settings in PHD2, although the internet suggests perhaps one of my 9x50mm guidescopes is 15mm shorter than the other, so maybe 10% out. I'll dig out my maths textbook, but I naively assumed double the error meant double the star size. After some googling I realise this is wrong. At worst, perhaps I had 0.25" is one axis and 0.5" in the other. I've looked back through the subs and realised: - some of the worst subs in the position I thought was bad appear to have double stars that look like "jumps" in the mount, so I might have some differential flexure/movement in the main OTA that's not in the guide scope. It's a brand new setup with a short focal length (280mm with reducer) and the OTA dovetail mount I got to may not be optimal. - however, even the best subs have some distortion in the corners but are good in the centre, so I think my reducer is too close. I hadn't realised the flattener spacing was so sensitive, or at least, so far away from the spec, because I measured very closely! It's textbook "too close" according to https://stargazerslounge.com/topic/340444-flattener-spacing-does-it-work/ and the software I use just showed me the top left corner, so the straight line stars looked like a tracking issue. So I think I probably have a few different issues going on and I jumped to the wrong conclusion - thanks for the guidance. I'll just wait another month for a clear sky to try again

Having intermittent issues with my FW and before I give up or accept the occasional reboot, I thought I'd try the recommendation I found in a few places to ensure the firmware was upgraded. However, since QHY changed their website, they don't appear to offer downloads for legacy kit, so thought I'd check if anyone has it? I don't think it matters, but this is the CFW2-M-US version.

Tried a few different targets last night as part of testing a new scope. I realized that my EQ6 has different tracking performance depending on where in the sky it's pointing. That makes sense. However, when I started to look at some images I finally joined the dots and realized this is what's causing me to sometimes get oval stars. I can't remember what order this was in in terms of height in the sky (although I imagine it's easy enough to guess), but let's say I was seeing tracking of 0.3/0.5" in PHD2 in RA/DEC in one position, 0.4/0.4" in another, and 0.5/0.3" in another. Exposing for 5 minutes, I can see oval stars for either of the 0.3/0.5" combos, but perfectly round stars for the subs tracking at 0.4/0.4". Based on my knowledge of what's going on here, I have no reason to expect to get equal tracking, because the errors are caused by different things. Is this something I have to live with, or do your mounts tend to track at the same rate? The error is pretty much regular noise rather than occaisional large jumps - so I don't see how shorter exposures would help? It's an old EQ6 but tends to track pretty well (always below 1" RMS, and as low as 0.6"). No belt mod yet, but I have one that I'm waiting to install. I realize this may help DEC tracking, but it's not always going to help the imbalance.

I tried a 130PDS on an EQ5 and whilst it's possible to achieve good results, if I had a time machine, I'd go back and get a HEQ5 immediately (rather than a few months later). People do report success with EQ5s, but mine was a bit of a disaster in DEC. That said, I'm much better at polar alignment now, so I do wonder how much better it'd perform if I could try again.

Not my area of expertise but these are going to be small. Check out astrobin e.g. https://www.astrobin.com/3my458/

Like others say, focus on a far way lamp post of chimney etc during the day. That'll get you close enough. Otherwise I often find that a guide scope or red dot finder is helpful when setting up a brand new scope.

I was unfamiliar with that software - but I guess it suffers the usual issue that it doesn't work with diffraction spikes. I'll give it a go anyway!

I don't it's possible to tell based on a graph alone. I don't consider myself that knowledgeable, but I can't see any reason why you should necessarily expect them to be similar, although obviously that's be ideal! I'd guess you have good PA and so very little correction is needed in DEC. For RA there are two options - why is it mechanically worse (imbalance, play in the gears) and then separately, can you make the guiding better without touching the mount. All of your RA corrections take two or three pulses to correct. I'd probably trust the guiding assistant over me, but Id start by dropping from 3s to 1s exposures and see if things improve.

Perfect - thank you. I'll take a look at those in the morning

Can't see much below 30 degrees South from my garden, so I picked up a second hand Skymax 127 (https://www.firstlightoptics.com/maksutov/skywatcher-skymax-127-ota.html) as as a portable planetary imaging scope. It's also light enough to be a grab and go visual scope for use with the star adventurer when we're camping, but as I've never much been in to visual astronomy, I have no idea what eyepieces I'd need. Can anyone recommend 2 or 3 of budget eyepieces? Focal length is 1500MM, F/12. No need to go for anything of particular high quality. It'd be good to get a decent view of planets, and whilst I realize the OTA isn't great at DSOs, I'm happy to have a go with it. I've generally found svbony hard to beat when you don't want to spend too much, so they'd probably be my default choice.

Assuming you mean the drop down is missing dark flats then that's the same as astroberry and is a little annoying. Fortunately I don't take fresh darks each session, so I can label the dark flats as darks without fear of getting mixed up!

I have no sympathy - I spent a week on the Caledonian canal so I know the views more than make up for it!

Really like target with a shorter focal length. May be the next thing I try - thanks!

I'd pretty much given up a month or so ago, but after selling a spare OTA to a more enthusiastic summer imager, I thought I'd recapture my "have a go" spirit and decided to collect some subs over the recent clear nights. This was fraught with issues aside from the lack of darkness. My scope, having previously held collimation for months, was no long collimated. After some testing swapping spacers to a new OTA, I'd lost track of the correct coma corrector spacing. One night partway through the collection, the frame shifted by half a degree, but magically kept guiding. This is what I ended up with: approx 6 hours of narrow band data, quickly processed. As expected, the Ha data dominates, and there's plenty to pick fault with. But I'm glad I tried - I would have thought this was magical when I started a year ago and it gives me something to benchmark against later in the year. So just wondering if anyone else is still having a go - and if you want to share?