rnobleeddy

I owned a 450D that someone else modded. Aside from dust (which wasn't an issue for me) I got on fine by adding 2" UV/IR cut filter to the optical train with a full spectrum mod. A basic filter may only set you back £30, so that's an option to consider if the parts are expensive or hard to fit.

Thanks. How far away does the ground matter? I have a clear view over fields to to the East, and have a couple of hundred meters to the south, so hopefully I'll have opportunities. Any recommendations for a barlow? My current camera would need a 2" barlow, so it's probably worth considering a smaller planetary cam + a 1.25" barlow as well.

Would it be worth using a coma corrector here? Thanks. Based on this, with this camera, a 2x barlow would probably suffice for Ha wavelength. I'll have a think though - a decent 2" barlow isn't cheap so I may consider something like a asi178mm-mono, as I also could also use it as a 2nd guide camera to prevent swapping kit as much.

+1 for this. Mine is still going strong after being well used this winter.

Thanks Vlad - very helpful as always. I will do the maths later and see how it looks!

Yeah, should have mentioned that. I guess I'm looking for close in shots or high-res mosaics. I've had a few goes at capturing the full disc and processing with autostakkert/registax already with OK results.

I'd like to get in to lunar imaging this summer, as a way to have something to target whilst the nights are lighter. I was hoping someone could help with some advice on kit. I already have a either a 200PDS (1000mm) or 250PDS (1200mm) Newtonian available and a QHY163M. FOV for the camera/250PDS is below. The camera should manage a little over 20fps at full res/8-bits. I've been trying to get a little more scientific in the way I approach DSO, and so my questions are around what is most important as I move to lunar imaging. - Is there anything fundamentally wrong with the plan to use this kit? I realize the pros don't use Newtonian's but I'm guessing this is primarily because there are more practical longer focal length scopes, and a higher f-ratio isn't an issue for lunar work? - This camera, with the 1200mm scope, leads to a resolution of 0.65" per pixel. I understand the principle of lucky imaging and have seen suggestions that lucky might mean as low as 0.1" , but not sure what's a sensible expectation? Assuming I'm under-sampling for lunar imagine, would a barlow or powermate be a sensible option? - As the moon doesn't suffer from much rotation, is the lack of fps an issue, or can I just record for longer? I guess this also comes down to a question of whether it's better to collect more frames at a lower FOV? I don't know what's considered top of the range for lunar imaging, but I'd guess over 100fps is easily achievable, but probably with a smaller chip. Obviously I'll be trying it out anyway, and I'm keen not to spend too much extra, primarily because my view is blocked to the south (below approx 30 degrees) and so Jupiter/Saturn are generally not visible and so whilst I might get mars sometimes, I can't really do a lot of planetary imaging. That said, if a cheapish longer focal length scope or a new camera would help a lot, I wouldn't rule them out.

My Pi has worked fine attached to a leg on the mount, with wifi repeater near a garden window. It suffered from occasional drop outs/slow down when attached to the OTA. Presumably the metal tube kills the signal, and in the garden, there's no walls for the signal to bounce off like there is in the house.

I guess that's depend. I'd imagine most kit would survive a little rain, so perhaps a rain sensor plus the app would work?

I don't really mind losing data - it's not worse than not having left it running in he first place. A mount collision may cost me a £70 replacement motor but power cuts are very rare. Rain is the big killer, but there are definitely nights where I consider the forecasts to be accurate enough.

If the kit you choose isn't too heavy, consider a HEQ5 mount over the EQ6. I've got an EQ6 and whilst you can certainly pack it up in the car, it's only worth the extra weight if you need the extra capacity. YMMV and there's loads of options for tuning, but I don't get the impression that guiding performance is significantly worse on an HEQ5. And it's a little cheaper.

If you're buying new this is very sensible advice. If you're considering second hand, I've seen 2nd hand ASI1600s (or equivalent) for less than 1/2 the price of a new ASI294. Of course, a second hand 294 would also be a good shout, but I've seen very few for sale, whereas there's been a lot of 1600's on offer recently.

All the time. I doubt it's be possible for me to do this hobby if the equipment had to be manned. Not many overnights yet as it's rare that it's been guaranteed to be dry but in the winter there were lots of 6 hour+ sessions where I set if off and checked in rarely. I've found meridian flips in EKOS to be a little hit and miss, but it's often possible to choose a target that won't require a flip, and just automate the mount parking at the end. Others appear to get flips to work well, but in any case, it's only been an issue with alignment failing so the data being poor. Ditto with focusing - it's great most of the time, but all it's gonna cost is data. My EQ6 is old so I'm not too precious about it - it crashed in to itself once and made a pretty nasty noise, but doesn't appear to have caused any lasting harm.

Use telescopius (or equivalent) to help find decent targets that are as far away from the moon as possible. That said, I've had little success with galaxies under full moon - whereas ha targets 40 degrees+ away from the moon look better. Definitely 4 hours. I can't remember ever regretting more data on a single target whereas I routinely get rubbish data because I get too optimisitc!

Thanks - just to follow up in case someone finds this in future: https://forums.atik-cameras.com/index.php?topic=329.0 has a decent looking dumbbell using GRBG (and the red is in the right place) but I concur with @JamesF the the manual says GBRG. Either way, the G's are in the right place - those two both look possible, but the other two look awful. I've up given up on the data I collected on M101 but I'd also grabbed a few subs on M13 if has an eye for color. This was the best 25x30s frames from a cloudy night processed as GRBG processed super quickly- so all things considered, the 15 year old camera is doing OK! I'm leaning towards GRBG , but if I definitively work out the correct bayer matrix in daylight, I'll update.

Unfortunately it's not quite that simple. The end on the cable you saw isn't ST4, but a similar looking cable that plugs in to the control box on a GOTO EQ5. Eqmod replaces the GOTO handset with your PC and also enables pulse-guiding. With the standard RA and DEC motors you're going to be limited to ST4 guiding. The good news is I had this setup and I didn't find guiding was any worse (I later upgraded to GOTO) - the only problem is finding the target manually can often be a challenge!

I've found that I can leave my mount setup in the garden under a decent quality cover. It's been out for about 4 months now and aside from some small patches of rust (counterweights, counterweight screws) it doesn't appear to be suffering. Makes a big difference, as it holds PA really well, so I can be imaging in about 10 minutes.

Realize this is a super old camera but wondering if anyone knows the bayer pattern? I mainly got it as a guide cam but as it was about the correct FOV for some galaxies I decided to try it out for imaging, I'm using it with Indi/Ekos which reports it as RGGB but this looks awful. One of the other early 314 models was (apparently) GRGB which is better, but I'm still convinced about. Obviously there's not a lot to try, but it's one of those situations (not enough in poor conditions) where I probably won't be able to tell from the image itself

Sorry - I wrote that without thinking about it. Unfortunately whilst I did study physics, I've since forgotten everything I ever knew . But I can learn again! DSS reports average FWHM ranging from low 3's to mid 4's across a few different stacks. As best I can tell, these are average values in pixels, so that's roughly 3.6" to 5.5". Just trying to work out if there's any decent way using free software to get a better idea of the spread of the FWHM. Edit - I'm using the relatively cheap Baader MPCC, which I also imagine isn't helping.

Do you mean 9x50mm? If so, it's very common - for example with https://www.firstlightoptics.com/adapters/astro-essentials-sky-watcher-9x50-finder-to-c-adapter.html (and there's a T-thread version available). I use a similar ZWO camera like this. If it's 8x50mm then I'm afraid I'm unsure if it's the same. But for example, the 200PDS ships with the 9x50 e..g. https://www.firstlightoptics.com/reflectors/skywatcher-explorer-200pds-heq5-pro.html

Thanks. Are there general purpose reducers for Newtonians? I've seen some coma correctors that change the focal length a little. I guess I should probably have said it's not ideal but not impossible. I can't seem to work out a way to screw the dovetail on to the mount on my own, as the mirror is so heavy and the scope too large to reach around. But I can almost always get help setting up, and I did manage to take it off the mount on my own. Longer term I'd probably just get a cover that I can use until the morning, but I've got the 130PDS routine down to less than 5 minutes at either end of the night, so it maybe just feels like a lot more hassle!

Thanks - really helpful explanation. Guiding with the 130PDS currently ranges between 0.7" and 1" depending on conditions/balance/wind/target position. Usually about 0.8". I guess I'll need another night to work out how much that degrades with the 250PDS. I'm guessing it is fair to assume most images will have some stars in them that are small, so it won't be dependent on where in the sky I was targeting? If all else was equal, is it fair to assume the 250PDS has 4x as much light hitting each pixel as the surface area of the aperture/mirror is 4x, or is that maths more complex?

It's within the spec of an EQ6 but mine is a little stiff so I think it's hard to balance. I'm planning to belt mod it once the nights get lighter, so will have a go at sorting it out then. The calc I found based on the pixel scale of the guide cam + imaging cam etc came out at about 240mm, so I guessed 180mm would probably suffice in a pinch. From what I've read 1200mm is about the limit after which an off-axis guider is essential - do you expect that the performance is likely to be limited by the guiding at that focal length?

I've been imaging using a 130PDS on an old but passable EQ6 for the last 9 months or so. Most recently with a QHY163M + FW, but I've tried a few cameras over the months. Mainly DSOs but might focus on lunar work in twilight over the lighter months. Someone nearby was selling a 250PDS so I thought I'd get it to give it a go, mainly as I was always a bit annoyed that some of my favorite images (e.g. the dumbell nebula, globular clusters) were so small. I guess I did this without really thinking it through. I got the 250PDS out last weekend, and had the usual first usage issues - focusing with no idea of where to start was hard, and my attempt to barlow a cheap refractor to make a guidescope ended up in failure, and so I ended up guiding with a 180mm guidescope in the finder shoe. My EQ6 struggled a bit under the increased load, and I don't have a flat panel that's anywhere near large enough for the 250PDS. But most of all, it's impossible for to safely get it out of the house/in to the garden without help, and that help usually goes to bed before midnight. So perhaps this isn't long for my collection. I've resolved to have another go before I sell it, but I also started to think about what I was hoping to achieve. The 130PDS + QHY163M end up at a resolution of 1.2" per pixel, which as I understand, is going to roughly the same as a good nights seeing? The 250PDS ends up at 0.65" per pixel, which is (according a google search) the best seeing you'd ever get on Earth and I don't think they mean my garden! So I may be doing this somewhat simplistically, but I'd guess this would mean the 250PDS is collecting ~4x as much light as the 130PDS I'd expect to collect more signal more quickly. Based on seeing, I'm not going to get a better resolution? So does it make sense to use the 250PDS? Hoping someone can sense check my ramblings above - which if true, mean that the 250PDS isn't going to "zoom" in on objects at all, so I've just got to weigh up if the size/weight is worth the extra light? Given that the 250PDS is impractically large for someone who doesn't have an obsy, are there other scopes that people would recommend for this kind of work? Or should I just stick with the trusty 130PDS?

I don't know how accurate it is, but see https://www.dpreview.com/forums/thread/2750802 - if that's believed, the older DSLR sensors are quite a bit worse. Anecdotally, I also owned a colour Atik 383 which is famed for having one of the worse QE of any astro camera, somewhere in the 40s. I didn't find that a massive improvement over my DSLR.