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Bagnaj97

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About Bagnaj97

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  1. Finally had a chance to play around with the data in PixInsight, I still don't have much of an idea what I'm doing in it, but I think I've improved things. The colour balance is certainly better.
  2. Widefield imaging is certainly possible with just a DSLR on a tripod. The general rule of thumb to avoid star trails is to keep the exposure length under 500/focal length, but that's for full frame rather than crop sensors, so it's more like 300/focal length with your camera (1.6x crop factor for Nikon). e.g. if you're using the kit 18-55 lens at the wide end (18mm focal length), 300/18 = 16.666 so try and keep your exposure under 16 seconds. At the long end (55mm) 300/55 = 5.45, so try and keep your exposure under 5.5 seconds or so. Of course it's just a guideline and you may find that, depending on your lens, sensor and tolerance for trailing, you can take longer exposures. A fast lens is better and generally you'll want to shoot wide open. This was taken with my D3300, 10 second exposure, f/1.8, ISO1600 using a Sigma 18-35 f/1.8 lens at 23mm:
  3. A lot say 40 days, but I've often had things from aliexpress or chinese/HK ebay sellers in a week or so - that's the risk!
  4. ~£20 if you don't mind waiting for shipping from China. https://www.aliexpress.com/item/S7959-new-medium-dovetail-telescope-accessories/1971053752.html https://www.aliexpress.com/item/Grus-s7933-dovetail-vixen-type-telescope-accessories/1971183711.html https://www.aliexpress.com/item/Grus-s-series-of-small-dovetail-sets-s7922-s7923-telescope-accessories/1971152991.html https://www.aliexpress.com/item/S7947-Vixen-Clamp-with-2-Brass-screws/1949864838.html <-- this one looks a bit sturdier but is £30. aliexpress is also a reasonably cheap source of dovetails, side-by-side clamps, tube rings etc. You just have to wait for shipping from China.
  5. I recently bought a Skywatcher 80ED and I added an Altair Astro 0.8x reducer/flattener because it's almost £100 cheaper than the Skywatcher 0.85x. This is the proper first light (I had a quick visual peek between clouds with no flattener) and I'm pretty pleased with it. I was slightly concerned about flexure, not because of my 3d printed tube rings (they're very solid!), but because of the 3d printed extension tube for the guide cam to reach focus. This is just a quick stack and levels in DSS at the end of the imaging session and the colour balance is a bit red, I'll process it in PI later. 18x600s lights (ISO200), 20x flats, 30x bias Scope: Skywatcher 80ED DS-Pro Mount: Celestron AVX Camera: Canon 450d (modded) Guiding: ST80, Altair GPCAM, PHD2 The subs have all got this line down them, which I've never seen previously. Any ideas what could cause it? I hope it doesn't mean the sensor is on its way out...
  6. It was reasonable along with a complete AZ3, a couple of Revelation/GSO barlows and a t-extension! From the pics and description it sounded as though the bottom had fallen out but the rest was intact, and the foam inner was all complete. It may not be pretty, but I reckon I'll be able to bodge it back into usefulness.
  7. I use this powered hub with gpcam (guiding), 450d (imaging) and usb-serial adapter (mount) running through it - https://www.amazon.co.uk/gp/product/B0192LVM86 It's USB3 and power is delivered through a micro-usb port which is very convenient. If you need 12v supply you could use a cigarette socket usb adapter.
  8. I used this one because I wanted the tabs to sit it over my ED80 dew shield - http://www.thingiverse.com/thing:1679036 I then modified the stl file to remove the mask bits, leaving a ring with tabs. Bit of Baader solar film glued to the ring and job done!
  9. I finally bought an ED80 (from the classifieds on here), only to realise that my previous side-by side tube rings were useless - I'd wrongly assumed that, both being made by Synta and 80mm, the ED80 and ST80 would have the same tube diameter. The ED80 actually has a 100mm tube diameter whereas the ST80 has a 90mm tube diameter. So I went back to Sketchup and designed some piggyback tube rings, they're up on thingiverse. STL files are there for 100mm rings, 90mm rings and mid section, so you can either print regular 90/100mm rings or 100mm bottoms (has a hole and cutout for mounting to dovetail), mid sections and 90mm tops. Unlike my previous side-by-side rings these don't need a large build plate (mid section is 166.5 x 121.7 x 20 according to Cura) A single piggyback ring can hold the weight of everything (I tested it horizontally over the sofa), so once you've got a pair of rings it should be plenty strong enough. I haven't tested it on a cold and frosty night, which would make the plastic more brittle, so if you're paranoid then you can use a 100mm ring in addition to the piggyback rings as I've done.
  10. I won't be drawing anywhere near 30 amps, the idea of the 30 amp breaker was simply to prevent the cable being the fuse in the event of a short. I suspect a short across the 6mm battery cable would get "slightly" warm, followed swiftly by fireworks. Realistically it's hard to imagine a scenario where the 30 amp breaker would ever trip - any problems are far more likely to be in the individual fused circuits and the blade fuses should blow first - I'm just being extra cautious.
  11. The other thing to bear in mind is that even with deep cycle batteries they shouldn't be discharged below 50% for optimum lifespan, and never below ~80%. So once you've worked out your power draw, and how long you expect an imaging session to be, double the number of amp hours! I found one of these useful for my power box build - http://www.ebay.co.uk/itm/12V-Car-4-2A-Dual-USB-Charger-Socket-Adapter-Voltage-Voltmeter-Motorcycle-Orange/252673267574?_trksid=p2045573.c100508.m3226&_trkparms=aid%3D555017%26algo%3DPL.CASSINI%26ao%3D1%26asc%3D20160706105120%26meid%3Deaf894c2adcc4f52b846e34180baabcd%26pid%3D100508%26rk%3D1%26rkt%3D1%26 Solves your USB power and voltmeter in a single device. If you're planning on using dew strips, you can use a PWM controller. I prefer the ones with the dial on a flying lead for ease of mounting - e.g. http://www.ebay.co.uk/itm/UK-New-12V-36V-3A-DC-Motor-Speed-Regulator-Controller-Switch-Control-PWM-HHO-RC-/152095041000 It's advisable to have a circuit breaker close to the positive battery terminal, just in case there's a short somewhere, I used one of these - http://www.ebay.co.uk/itm/20-100A-Car-Audio-Inline-Circuit-Breaker-Fuse-Holder-12v-24v-System-Protection-/221846538313 I also fused the individual sockets etc with a blade fuse box - e.g. http://www.ebay.co.uk/itm/12V-24V-10-Way-Blade-Fuse-Box-Holder-LED-Warning-Light-Kit-Car-Race-Rally-Marine-/201624907701 So in my case, positive terminal --> 30a circuit breaker --> fuse box --> sockets/PWM/USB --> service connector block -> negative terminal. I used 6mm cable between the battery and fuse box/connector block and 1.5mm cable for the individual socket circuits between the fuse box and connector block. Of course you could just use something like this, but it's better to do things safely!
  12. In your pics the circle K is also on the front of the lens cell after the D=76.2mm F=1250mm - no loup required!
  13. The printer's been busy today. Now I need to buy an ED80 to sit next to the ST80, roll on payday... The second bottom half is currently printing. I've discovered that ABS is horrible for prints this size, it really wants to warp. Masking tape and abs juice mostly works, but near the end of the print it's pulling the masking tape off the bed. I'm not sure PLA is durable enough for this (I don't store it anywhere warm, but might do some solar observing so it'll be sat in the heat). Has anyone printed in PETG? It's meant to have the durability of ABS but it's easier to print and doesn't stink - my concern is that it's more flexible and I don't want flexure - just how flexible/rigid is it? For testing I balanced the bottom piece and hung 3kg off either end (from the bolt holes) without the top in place and it was fine. Given that the actual load will be nearer the centre, the top will be in place to brace it and there will be the second pair of rings I've got absolutely no concerns about it not taking the weight of the scopes - I could almost certainly make it less chunky, but chunky and strong reduces the chance of flexure. Total weight of 2 top pieces, 2 bottom pieces, the handle and all the nuts and bolts is 509g, dovetail and any hex-thumbscrew adapters will be on top. I need to print some M6 hex thumbscrew thingies now. I did a test one to make sure I've got the internal dimensions correct (grey in second pic) but need to give it something to grip - a smooth cylinder isn't great. STLs and Sketchup files will go up on Thingiverse, but I've only just signed up and there's a 24hr block before new users can publish on there. It should appear here - http://www.thingiverse.com/thing:2116466
  14. I bought myself a Hictop Prusa i3 clone and put it together over the weekend. It's my first 3d printer but I did a fair bit of research before taking the plunge - lead screws, aluminium frame, heated bed, auto leveling and a good size build volume are what decided it in the end. I was pleasantly surprised at not having to solder or crimp anything either - just putting plugs in the right places! Has anyone tried printing tube rings? I've gained an ST80 but it was OTA only and I have no rings...
  15. According to the backyardEOS compatibility table the 350d requires a serial connection for bulb exposures, so if you're planning to PC control the camera I'd stick to 450d/1000d or newer. They have the benefit of live view too, which when zoomed in is helpful for focusing. I'd recommend Wex for used kit - unless otherwise stated all their used gear has a 12 month warranty. I've had a few bits and pieces from them and had no issues, although I've not had to test the warranty...