Jasonb

Yep, that's what I did, just to get rid of excess. It's not like it's falling off all over the place or anything like that, some stuff just comes loose as you're moving the material around. Once it's in place, it's no longer being manipulated, so I haven't had any issues with excess lint.

Thanks for your replies... Sounds like I don't need to be going higher with ISO, and in fact could be going lower. And it also sounds like that a lot more shots are needed! I'll have a look at GIMP and Siril when I get a chance!

Hi there, I'm dipping my toe into AP, basically trying to see if I can capture what I see through the EP. I have a basic setup, and I'm not planning to spending any money to change it or improve it, and to be quite blunt, I'm not looking for any advice regarding equipment to buy etc.! I'm purely trying to maximise what I'm getting out of what I have, and a lot of that seems to come down to Camera settings, Deep Sky Stacker settings, and further Processing! I'm mainly interesting in Clusters and DSOs, like Galaxies etc. But I'm not expecting miracles here. I can't *see* beautiful, colourful, spiral-armed Galaxies through my EP, so I don't expect to capture them via this setup either. So, to start, I have a Skywatcher 150P Newtonian on an Alt-Az mount. I have a loan of a Canon M50 Mirrorless camera, and I have a T-Ring. So the camera is directly attached to the Telescope focuser, and I'm able to get focus. I've done a fair bit of reading about camera settings, and I'm shooting in RAW, I've turned off all the Camera Noise Reduction settings, and have White Balance on the Camera set to Day. I've tried ISO at 3200 and 6400 and am not sure which is better, or if I should go higher still. Using a calculator I found online (https://www.lonelyspeck.com/advanced-astrophotography-shutter-time-calculator/) I am shooting at 0.3s shutter speeds, as this means I'm not getting any Star Trails with my non-tracking mount. The aperture is basically set to Zero as once the lens is off the camera my Telescope becomes the lens. What I'm currently doing is I use an EP to find what I want (say the Leo Triplet) and then I connect the camera to the Scope. I use the Camera screen to position the stars I can see on it, zoom in on the screen to focus (my scope has a dual-speed focus) and then I zoom out again. I note where a couple of stars are on the screen, and then I press the shutter. I have the shutter set up to wait for a few seconds after I press it, and then take 10 frames. At 0.3s shutter, this doesn't take long! I then use the slow motion controls to slightly adjust the positions of the stars on the camera screen back to their starting point, and I press the shutter again. Recently I've been getting 80 frames this way, so basically 24 seconds of exposure in total, but clearly that can very easily be increased! When that's done, I put the telescope cover on, and take another 20 frames with the exact same settings for dark frames, and then I change the Shutter speed to the fastest speed possible (1/4000) and leave everything else the same and take 50 frames for Bias. I reuse these Bias frames, having taken note of the ISO first. So, that's the actual taking pictures part! Any advice around that? It seems obvious, but should I take more, like hundreds more, light frames, just to up that total exposure time? Any advice about ISO, should I go higher? Next is DSS. Following a few posts online, here's what I do. I change the RAW Brightness setting to 2.0000 and then I add all the Lights, and register them. I always check the "Star Detection Threshold" and try to get as high as possible (like in the low hundreds if that is possible, but at least getting close to 100), without it being obviously artificially too high. Once the Lights are registered, I have a look at the list of them, choose the one with the best score, and mark that as the reference file. I then change the RAW brightness back to 1.0000 and I add the Darks and Bias, and register them, telling it *not* to register already registered frames (thereby ignoring the already registered Lights). Then I stack them, going with Intersection Mode, and any other recommended settings (which tend to be Kappa Sigma Clipping with my short exposures.). It's set to use the best 95% of the frames for stacking, but the best I've managed is 72 out of 80, with around 50 being more usual. So, that's DSS and stacking, Any advice around that? Any settings/steps I'm missing, or stuff I shouldn't be doing that I am? Finally, probably my biggest issue, processing after stacking. I say it's my biggest issue because I don't know what I'm doing here, and therefore haven't really done anything. I have played with the basic processing in DSS (again, following a tutorial) which basically sets a Luminance Curve and then I move the R/G/B levels around. Yes, that *does* make everything brighter, so I can see more stars, and even smudges of a couple of the Leo Triplet Galaxies, but the sky is also brighter too. I have had Photoshop, GIMP and Rawtherapee recommended to me by friends on here, but haven't tried them yet. A friend on here put one of my stacked images through Photoshop but she basically said that the image is too dark, and doesn't have enough light (the Histogram is a thin spike on the left hand side, with no real room to the left of it to stretch it that way for example). So, that suggests that I need to fix something earlier in the process (taking pictures or DSS) before I get to the processing stage. Again I wonder, what are my best options here. Is the answer to getting more light/data into my picture just to take a lot more light frames? That's about it, I'd appreciate any advice that's out there. As I said at the start, I *know* this a very basic AP setup, and I'm realistic about my results from it. I'm not looking to change my scope/mount/camera etc. I'm just trying to get to a point where the final picture I get is *good* for the setup I have. In other words, to wring the most out of this setup. Any questions, please ask away, and if it would help at all for me to upload any of my light frames, or one of the DSS autosaved stacked files, let me know. Thanks..

The water butt is a good solution alright!

Thanks for that, that's an impressive set up you have there!

Once again, thanks for the replies, they're much appreciated!

Wow, thanks for all the replies, some great information here. I appreciate people taking the time to share their knowledge and experience. It sounds like I wouldn't have to worry about Dobs being less stable on uneven ground, in fact it sounds like Dobs are probably more stable, especially for heavier Newts. As @Captain Scarlet says, the AZEQ6 is fine with his 12" Newt, but that's nearly £2,000 worth of Mount! So, in general, it seems an 8" Newt you can get away with some of the relatively cheaper mounts (Sky Tee 2 etc.) but anything more than that is going to be a Dob or a *serious* mount. One thing a friend of mine raised, that I hadn't though of. With a Dob, the design gives you a low viewpoint, in terms of the mirror height. The primary is *much* lower that it would be with a Newt on a Mount, so if you're in a garden with a fence/wall around it, a lot of the lower sky will be invisible for you. Has anyone else experienced that? It's not like you can put a 10" Dob up on a table! And Magnus, Baltimore is a little more distance than a "nip down", but I'd love to come visit some day/night, just to look at the scopes you have!

Hi there, First off, I need to stress that this is a hypothetical post, I don't have the money to be buying anything right now! I currently have a 6" Skywatcher Reflector on a AZ5 Mount and a heavy duty steel tripod. It's pretty much a grab and go set up, I can easily get it in the car and I can set it up within a couple of minutes. The 6" Reflector with a RACI Finder Scope and EP is probably getting close to the capacity of the AZ5, though the heavy duty steel tripod helps with that. I started wondering though, if I were ever to go larger (8" or maybe 10" max), what is the best mount to be using? I don't really want to go down the EQ mount route, I am perfectly happy with Alt-Az. But an 8" or 10" Reflector would be too much for the AZ5, so a new mount would be needed too, either a Sky-Tee 2 or, even more expensive, a Rowan Mount. Or I could look at going down the Dob route instead, to handle the 8" or 10" Scope. I'd be worried though about the Dob base being less forgiving about the ground it's been placed on, compared to a tripod, as it would need to be fairly flat, right? I suppose when it comes down to it, my question really is about what's the best type of mount to be using for the larger/heavier scopes? Thoughts please?

Wow! Love this, I was about to say thanks for supplying us with a diagram showing them, but where's the photo? Excellent result...

Thanks! I did the whole of the inner tube as well...

Thanks for the replies, I think I'm safe with having some slight overlap and I don't think it's causing any light path issues...

Hi everyone, I flocked the inside of my SkyWatcher 150P yesterday, with a roll of flocking material I got from FLO. It actually turned out to be an easier process than I thought, once I got over the fear of removing the mirrors from the tube! As I had the mirrors out anyhow, I decided to also flock the back and sides of the Secondary Mirror and holder. This was harder due to the complex shapes/curves involved. I finally ended up with this... Now I'm not too worried about the overlapping flocking material on the barrel of the mirror holder, as that's effectively not in the light path in my mind (as the back of the mirror is wider than the barrel) but I am curious about the overlapping flocking material on the edges of the mirror. It means that the edges are no longer perfectly smooth and uniform, and some bits (where it overlaps) are a little thicker/wider. So, my question is this, will that overlapping material on the edges of the secondary cause any issues for me? I don't know, reducing light going down the tube (barely I guess), causing any observing issues etc.? I really don't know if it will or not, but I do know that when I was doing collimation I could see that the edges of the secondary were no longer smooth and uniform. I'm pretty new to all this, so would appreciate any thoughts! Thanks!

Two separate deliveries, the Flocking Material and Solar Filter from FLO, and the Dual Speed Focuser from fellow SGLer @Greg Shaw (thanks Greg!). All upgrades for my Skywatcher Explorer 150P...

Hijacking the thread again, sorry! Anyone going to Cosmos 2023 tomorrow? @Padraic M, @Bogmonster, @Nicola Fletcher, @Muc, @LukeSkywatcher?

Hi there, I know there are a few Irish astronomers on here, anyone else going to the Midland Astronomy Club's Cosmos 2023, on this Saturday? Details are here... https://midlandsastronomy.ie/cosmos-2023 Would be great to arrange a mini-SGL meet up there, put some names to faces etc, and swap some tips and advice. Thanks... Jason.