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  2. I'd say no, as my mount is fixed, I just need to check Polar alignment every few months, but after that I just instruct SGPro\APT to slew & then plate solve...
  3. Congrats! The ES 24mm 68 is a great eyepiece.
  4. Chromatic aberration is not the only issue with cheap short-focus crown/flint refractors. A lot of them suffer significant amounts of spherical aberration as well, and the field curvature might be a lot less predictable/ correctable. Alacant's suggestion with a Wratten #8 is worth a punt but that's about as far as I'd go. A least from the theoretical point of view, your Newt is a known quantity...any coma corrector to suit the f-ratio should be giving very acceptable results out of the box assuming the spacing is correct. We are taking it as read that you are looking to do deep-sky work here..I don't think it makes it clear in the initial post. A decent long-focus achromat is capable of very reasonable results on planets/ moon with nothing more than a cheap UV/IR filter. Are there any other ways you could optimise your results from the newt, at minimal expense? Are you using a Bahtinov mask to focus? Is the CC spacing optimised? Would a cheap LPR filter help? Processing? If you're determined to go the refractor route, the old blue Skywatcher ED80s often change hands for about £200 secondhand...mine did! They are a very good start, if a bit slow. The focal reducer is a very worthwhile addition. I've been doing astrophotography for 40 years and I'm still amazed at my own talent to mess it up completely either by clumsiness or forgetfulness. Given the infrequent good nights, anything that makes the data aquisition simpler and more reliable has to be a good thing. A small ED frac can be a big step in this direction providing it suits your chosen targets (wide field); easier to mount (half the weight, half the focal length, less than half the wind sail area), don't go out of collimation. They are about the closest thing in astronomy to kit which "just works". It might be worth saving up....optimise the return on those precious hours spent outside. RL
  5. I use the Celestron AVX mount and I also use Astrophotography Tool when imaging. When I start my imaging session I will undertake a two star alignment then move to my target and THEN platesolve to ensure I have the object centred. My question is do I need to bother with two star alignment (or any other Celestron alignment for that matter)? My thought would be to Polar align then take a shot of Polaris and plate solve this, sync the result to the mount then “Goto” from there. The only issue I have is when you switch the mount on and enter time/date etc it asks you to do a star alignment so how do I ignore this or do I do just that, ignore it! Sorry for the rambling question. john
  6. Peter, The circuit as drawn should be correct. The diode where it is, protects the whole circuit and not just a part of it. Following the diode connections it is connected across the motor all the time which is what you want. Redrawing the circuit in a different way but keeping the connections the same would make it a lot clearer. If I have time I'll redraw it which should hopefully make it easier to follow. Hope the test goes well. Using a small motor for testing is a good idea, as if there are problems it shouldn't do any harm. Alan
  7. Hi folks, coming back to this again I've taken the plunge and got a 24mm ES 68* and just WOW. Love the increase in FoV angle from the Plossls, (profile pic is camera on phone looking down the EP, hand held). My next target is the mid-range and think I'm in love with the ES EPs. Made a fancy spreadsheet that shows the calculations of magnification, exit pupil, and TFoV (from both the quoted AFoV and the likely more accurate field stop). With this spreadsheet, I've also added columns to show how much of the EP is filled with different objects - eg the moon takes up ~40% of the 68*ES24, or ~15% taken up by M82 and can compare this to any other EP I'm thinking about. I was about to take the jump for birthday with a 6.7 82*, then looked and thought about barlowing - there's lots of discussion on this again, but the ES x2 FocalLengthExtender may be just what I'm after - this would allow me to have a 68* 12mm (using the 68-24) with half decent ER, with the possibility of later getting the 82*14mm and effectively having FOVs that would allow the moon to fill 40%, 58%, 80% and 115% of the eyepiece viewing (taken from the 24mm, 14mm, 24+x2 and 14+x2 lens choices (magnifications of 50x, 85x, 100x, 170x respectively) - the TFoVs being 1.3*,0.9*, 0.65* and 0.45* again respectively looking at that possible EP setup. I guess ignoring the 14mm for now (it may be better to get the 8.8mm), I'm wondering if the x2 is the best choice now so that I'd have a 24 & 12. Is the x2 a good choice that would be financially beneficial as EP collection grows... What are everyones thoughts on the ES x2? Better than Barlow? The ER won't change, which is fine, probably better. (The TV Powermate is well out of any range, so please don't suggest it!) Do most of you avoid focal-length extenders? Thanks again
  8. Might not be relevant but I have the Altair 80mm ED Starwave and its a fantastic powerful scope. I love it. I use it lots and the build quality is fabulous, the focuser is top quality and it gives great views. I would think the big brother would be just as good? Steve
  9. i'm not an expert reviewer and only use the simplest routines...... ie... scheduling a Ha LRGB or narrowband sequence , but a couple of things I cannot quite suss out, probably need to read the manual a bit better !!! I have a 9x 1.25" insert on the EFW2, but I cannot sequence FW position 9, it only seems to go up to 8 on the scheduler. Not critical but annoying because I have Hbeta in FWposition 9. Some sequences just will not start, is it because I have the exposure loop still active....??... well when I turn it off, it still doesn't start. Have to reload program to get it to work. Scheduler seems to write out directories of all the previous sequences I have had. ie. I store images in folders with the date as the 'name', when I create a new sequence it writes out all the previous ones as well, there must be a way to reset all of this. Other than that, good piece of software. I used to like the Artemis one as well. Straightforward and it works. Sean.
  10. For (a), if this was a real situation and not a typical simplistic course question, then you would also need to consider the solar spectral energy density, the atmospheric transmission and the efficiency of the solar cells with wavelength. (Not sure why they have given you the diameter of the sun, except that with this and the luminosity, you could estimate the temperature and hence the spectral energy density, though I doubt that is what they intended. Cheers Robin EDIT: Holy thread resurrection batman!
  11. same here had a qwick look couldnt spot anything at high mag to image. great set David, sols gone abit quiet again mate. charl.
  12. Thanks all, going to have a look see tonight and see how well my mount tracks.
  13. Indeed, the camera needs to go in the fridge overnight running 30 minute darks to make a master dark before I decide if there's an issue that a fw upgrade is required to fix.
  14. My flat panel should arrive tomorrow. In APT the ADU is set as default at 20,000 should I leave it there or change it. Some people have mentioned 12,000 is better? Or use a histogram and do it that way? I would like a good start to my flats probably take 40 per filter. Regards David
  15. I can get around 3 mins with EQM-35 pro, which for all intents and purposes is a 'lesser' mount than yours. I use a Skywatcher AP 80 Evostar. If I am even a little bit careless in the polar alignment, I am lucky to get 1 min. With a lot of practice I am now able to polar align precisely enough for 2½ mins 'precision' within 6 or 7 mins. I usualy set up my polar alignment without counterweights or scope. But I always check when I have fitted the scope and counterweights, if I'm still good. Quite a few times I've had to re-adjust after adding weight to the mount.
  16. Lovely clear blue sky here yesterday but nothing worth imaging, at least Ca-K looks cool even if there's no activity to speak of, well done. Dave
  17. I have an ex Olly Atik4000OSC, does this provenance make them worth more ? perhaps he could print us a certificate Dave
  18. Hi. A cheap wratten #8 takes care of most of the blue without altering the rest of the colour too much. This is with a €100 ar80. Worth a go? HTH
  19. Today
  20. Some speculation about it here: https://www.cloudynights.com/topic/655834-anyone-know-anything-about-this-notional-new-16-bit-adc-zwo-cam/ but nothing much concrete. Sounds like it's still relatively early in the development stage. James
  21. Hi Neil @Coastliner Just wondering if youd had a successful resolution? I'm thinking of getting either an AZ-EQ5 Pier mount tripod, or an EQM-35 ... main drivers being portability and ability to store things/carry equipment up and down stairs , but worried about the wobble if using, say, an EdgeHD 8. Best wishes Sanj
  22. How does it look from the back? (Mirror slits are normally back surfaced so you dont get ghost spectra from internal reflections reflected into the spectrograph) Cheers Robin
  23. I think you'll end up chasing your tail. I'd just stick with the Newt till a good apo turned up. Olly
  24. Thanks for this tip Olly. I've always just tried to align them as central as possible as the foot of each channel is rarely the same width in my images. I will have a go with this next time round.
  25. I just stumbled on this camera being advertised on the OPT site and they take pre orders. When I googled it I see that OPT may have indicated a price of 5000 USD at some point (see attached screen dump) but on the OPT site no price is now given. https://optcorp.com/products/zwo-asi6200mm-p Do anyone know anything more about this camera? Seems like the one many have waited for.....
  26. Can anyone tell me where I can download a "Strip down" or repair manual or instructions for this Mount, I have a knocking noise on slewing and need to inspect it
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