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discardedastro

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Everything posted by discardedastro

  1. The ultrasonic things are fairly useless. UV fly zappers are the way to go - there are loft versions that have an automatic cut-off when the tray fills up. Obviously switch off before observing but a cheap smart plug will sort that out. I would look to brush strips for sealing around moving portions. They'll make a very fly-proof barrier without inhibiting movement.
  2. Hi all, In trying to assemble a mosaic and mid-way through capture doing some rebuilds of my imaging train that required some rotation of components relative to each other, I've added "automatic rotation" to my list of things I'd like my imaging rig to be able to do. Looking around the available options all look to have a T2 or similar thread on the camera side and either a 2" eyepiece or thread adapter (M48 or similar) on the downstream side. My current optical train looks like this: In practical terms this is: Paracorr with T2 thread adapter ZWO v2 OAG
  3. Agree - that looks like an issue with your flats. Can't imagine any physical issue would produce such an effect (it'd be pretty extreme vignetting, and that wouldn't be consistent across cameras with different sensors!). How are you generating flats, physically and in terms of processing?
  4. Have to be careful with rules of origin on that now, of course, which is another thing tripping up a lot of exporters. Quite a good thread here on twitter from a wine importer about the struggles with the IT system. There's also a (very long) thread of examples of non-tarrif barriers causing fun over here, which is useful as a view of how this is affecting different industries - it is interesting, in a slighly morbid way, to watch. Edit: Hum, new theme and Twitter embeds don't seem to work very well but I can't paste in links without the editor instantly turning them into
  5. To fix a lot of this, for sure. I think a lot of the pain is that we're well above "normal" shipping-from-outside-EU timelines because of general trade chaos due to COVID anyway, and then there's the paperwork nightmares atop of that. Once COVID starts to subside in 2022 that'll let general trade routes get back into the swing of things (or precipitate change to re-establish "normal" throughput/timing on new routes/volumes). The paperwork situation will bed in as exporters and importers figure out what to do and govt (we hope) makes long-awaited fixes to their IT systems so they can actually w
  6. It does seem like all the clear nights we've gotten in the southern UK have coincided with bright full moons so far this year. Got the scope out last night and got some good imaging in for a few hours, at least, but contrast-wise it's nothing to write home about with that much background illumination.
  7. Right now retailers will probably sell to you ex VAT and declare the value of goods for you to pay at the border, and let the shipping company handle it. There are, broadly, no customs tariffs - but there are undoubtedly going to be handling fees paid by you as an importer. As an example, I bought a keyboard stand and some other bits from a German retailer on the 3rd. One half of the shipment should arrive next week but the other half only had 3 copies of the paperwork attached, not 4, so now the seller is having to send more (physical!) paperwork to the UK to marry up with the shipment b
  8. OK, so hardly "new" ground but I thought I'd write up my experience with the Paracorr. This relates to the Type 2 Visual-Imaging Paracorr with tunable top, bought from FLO; I'm using it with a ZWO imaging train and Skywatcher 200PDS in a Baader Steeltrack focuser. Quickly after getting it I realised I was missing a key part to adapt the front surface to T2 threads - the supplied threads under the tunable top are an "odd" size and won't fit anything without adaptation. Unfortunately FLO don't stock this but Teleskop Express do, so that was sorted quickly enough. Build quality is
  9. The way I sanity check my adapter configuration is to grab an eyepiece with a similar field of view and make a note (mentally or with some dry-wipe marker) of where the first lens in the bottom of the eyepiece is when viewed from the outside. Then, get that to focus. You now have a mark on the outside which is roughly where you need to place your focal plane. You can then simply hold up your adapters (or measure, etc) and see if you get the same answer, more or less! Then adjust to suit. On Newts, often you'll surprise yourself with how far back you need the camera's sensor to be relative
  10. There is a central tax/VAT clearance infrastructure for the EU (VIES, MOSS) and so for almost all EU-EU trade including EU-NI you just get registered in there and it's pretty trivial. UK govt opted not to stay in VIES/MOSS etc and make this easy - so now every EU company who wants to sell to consumers in the UK has to register with HMRC and then report all their VAT into HMRC rather than VIES. That sounds simple, but in reality the HMRC registration and VAT pathway is really, really complex - and on top of that there's nearly no automation or tools for it in systems etc. though that will come
  11. I've not taken the tree down yet, but didn't do outdoor lights just to help with local light pollution! Not that it's helped the observing much, mind you, with all the clouds...
  12. Try the chunkier half-face masks if you want it for warmth, stuff like the 3M 6500 half-face respirators have a downward vent and a very good (comfy) seal that won't let air fog up your glasses. You'll have to tape some filter material over the exhaust to protect those around you, though, but comfy as heck for all day wear.
  13. It's pretty clear outside now but it's also nearly 1am. Went out earlier and it was a cloudy mess, and I'm too tired to start faffing around with capture software. Hoping for clear skies this weekend maybe.
  14. If you are doing AP in the UK seriously then I think an automated observatory is a must-have, or a lot of patience. The clear nights I've had, I still need to be asleep for 1am to work the next day, and maybe 5-6 more hours go past unused. Add it up over a year like this one and that's easily doubling or even more your hours-of-clear-skies count. But if you're happy waiting and viewing it as a long term thing, then, yeah, the expense is less mad and you can still make great stuff in terms of images. I do think it ends up being something where you absolutely need the telescope to be doing
  15. I will add that if you have a Barlow lens then the laser Barlow trick can work very well as a collimation aid/check and is quick and easy for no extra money - there's lots of guides if you do a search on SGL. But the comments on focuser stability etc will always be true. I found one of the best upgrades to my 200PDS was to replace the focuser with a Baader Steeltrack Diamond - the improved rigidity and stability made collimation much more robust. If you're routinely using extension tubes etc then those will also play a role - the TeleVue extension tubes I've found to be very good in this
  16. Will add to AlexK's good tips there that if you do use a laser pointer be very sure there are no aircraft anywhere near where you're pointing!
  17. I ran an entry-level iTelescope plan for the last year and a half; I cancelled it this month. Practically the exposure-time-vs-cost equation, even doing things like imaging in discounted periods like full moon, didn't stack up for me - I ended up generating a few hours of OIII data for a target I'd collected Ha for locally, but that's about all. While having access to telescopes with clear skies is a great theory, in practice it's an expensive way to go I think...
  18. Quite a few bits of imaging/guiding software will do dithering, but most will only do that through guiding - e.g. applying a small guide "correction" to intentionally dither. The reason being that some (many) mounts don't do small corrections well if instructed to slew to new coordinates, and software support for sending correction pulses directly has been a bit variable historically (so ST4 was used along with special ST4 ports provided on guide cameras or in separate adapters).
  19. So it comes down to what you're trying to correct for. Widefield, you won't see - generally - fine mount errors, which is generally why guiding isn't as necessary as it is with narrow FOVs. This is mostly what guide systems work to correct. In this case you need to respond to errors more rapidly than once every 30, 60, 120, 300, 600, 900s as you'd normally use for imaging. Consequently guide systems work on the basis of a separate, short-time-domain exposure because this gives you enough information quickly enough to adjust the mount motion to correct your error before it affects the
  20. It still eludes me, really! I find it's really helpful to get yourself comfortable viewing the polar scope so you're not rushing. Bring a phone with Stellarium or similar so you can look at a star atlas. Before you even get down there, use your phone's compass (after doing the figure-of-8 calibration) or a real compass to get the alignment "close" - you can do this in daylight in the "warm". Same goes for latitude alignment - level the tripod/base and set accordingly for your latitude. I then use the star atlas to work out which bright star I'm looking at (once I have one) and naviga
  21. Couple from earlier in the year, before I got my Paracorr, of M51 and NGC 7023 on the 200PDS: And one from later in the year - ever since I got the Paracorr I've had clouds and dewy nights alternatively, so not much time imaging!
  22. That's fair! the NUCs are great little boxes. You can get Mini-ITX format machines which will take 12V as their input and run Windows but a bit more work.
  23. It'll be a buck-boost converter. I'd stick to switched-mode supplies fed from mains if you've got mains handy - it'll be cleaner output for the PC - but decent quality buck-boost converters with plenty of output capacitance definitely exist. That or use a Raspberry Pi or similar 5V PC if you're using a Linux stack like KStars/Ekos - not so handy if you need Windows on the pier/scope though, but 5V is much easier to produce well than 20V!
  24. Over short runs you'll be fine - if you want to be paranoid use Cat6A and attach the screen to a good ground, or use fibre and media converters. Practically speaking on 20-30m it's not going to be an issue. 6 versus 5e won't make any difference - 5e and 6 are identically shielded/screened, and 6A is too for the purposes of your install. Fibre and media converters is definitely the best answer because there's no metallic path to the house, but adds £80 in bits quite easily. At 30-50m you can just buy off-the-shelf patch cables, though, so actually quite cheap overall - a 30m duplex LC sing
  25. That's quite a lot - likely the mount is being pushed around or moved if there's that much error between sessions. I don't use Astroberry but in KStars/Ekos I start all my sessions by wiping the alignment data after unpark and a quick focus if required, and then running the Ekos mount model tool which will point the scope at 8 or so (configurable) different areas of the sky and give you a great basis for future alignment calculations. Only takes a few minutes and sets everything up pretty well regardless of the intervening conditions. I do find that - especially since I slacken my cl
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