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gnomus

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About gnomus

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  1. I agree with try what you have first. Have you done a search for 'barn-door trackers' - these are things that you make yourself and will cost pennies. Best to save and get the right thing, rather than just what you can afford. At your age, you have less time pressure than us oldies!!!
  2. As I said before, I'd take a look at the Star Adventurer package. There are plenty of reviews on You Tube you could take a look at.
  3. That sounds about right, but you will need to see what your own lens is like. If you track, of course, you will manage longer exposures.
  4. There is something called the 600 or 500 rule. Take 500 and divide it by the focal length of the lens used. This gives you the supposed maximum exposure time (in seconds) before you will see trails. (So for a 50mm lens that would be 10 seconds.) Of course, this will depend on how fussy you are. Also note, that you may not be able to use the lens wide open for astro work. In daytime shots, you won't see the minor aberrations in the corners, but they will stick out like a sore thumb on astro shots - your corner stars turn into ugly 'seagulls' very quickly. So always come down a stop or two from wide-open. You will need to test this for yourself, of course and, once again, it will depend on how fussy you are. I have tried untracked milky way shots a couple of times (including once from a dark sky site) - I have always been a bit disappointed.
  5. The 50mm lenses from Nikon and Canon are cheap, but they are also good quality. 50mm was/is the 'standard (or normal)' lens back in the 35mm film days. As such there were economies of scale. I would take a fixed 50mm over a 18-55 kit lens any day. But, if money is tight, why bother with a kit? Why not get body only? Why not buy used? This chap offers some used 'astro-modified' cameras. http://cheapastrophotography.vpweb.co.uk/Available-Cameras.html (You may have to scroll down to the used section). Or look around this site for good used cameras. You may find that most folks using DSLRs for astro work use Canon. There may be some reasons why Canons are better than Nikons for astro work. But the fact that there are more Canons around means that the software available might be more 'Canon-friendly'. Things could have changed, of course, its been a couple of years since I did any DSLR astro work (with a Nikon). As to mounts, if I was looking to do Milky Way (and beyond) widefield work, I would probably be looking at something like this: https://www.firstlightoptics.com/skywatcher-star-adventurer/skywatcher-star-adventurer-astronomy-bundle.html They seem to get reasonably good reviews. And you don't need to buy the whole kit to begin with, of course. Once again these occasionally come up used. In AstroPhotography, it is very easy to make the mistake of buying the wriong thing because it is a bit cheaper. And this leads to buying twice ...... I have done this too many times, myself.
  6. Thanks Rodd.
  7. That's pretty good. It has, to my way of thinking, a touch too much green. I'm not sure if you have any 'green-reducing' tools available to you. SCNR in PI is what I use: there is also HLVG ('Hasta La Vista Green') for PS. Here is what one pass of SCNR did to your image (once I ran SCNR, I thought that just a hint of extra Saturation was in order - oh and I boosted the background a shade - the original was a bit dark). I hope you don't mind me doing this - it can be very annoying when someone downloads and then messes around with your image:
  8. As commanded (this is my Esprit 120 with a Feathertouch focuser but the principles are the same): Under 'Set Filters': Note that it doesn't matter what Lum is set at (although having it somewhere near a number where you once might have had focus seems to me to be sensible). In this case there is a -44 difference between Lum and Red. If, on the night, Lum focuses at 15400, SGP will just remove the 44 steps when using the Red filter because SGP uses relative offsets. You will probably not be able to find an 'absolute' position for Lum during the night you run your tests since there is no such thing. Lum will focus at different points as the temperature and other factors change. You may as well, therefore, pick a number that makes the subsequent arithmetic easy. This is what I have under the 'Focus' Tab in my Equipment Profile: Nothing especially exciting here. And finally, when I click the button with the yellow arrow (please note, if you have a yellow arrow next to your button you should contact SGP), I have: Some of these will be equipment dependent and others will be matters of taste. I have found that I need to refocus every 0.5 degrees with my Esprit 120, whereas 1 degree is fine with the WO Star 71s. You might decide you want to check focus every 60 minutes irrespective of whether there has been a temperature change. It makes most sense to me to autofocus with Lum. Set a big number for backlash. This is not something you want to try to calculate 'precisely' (again probably impossible). Rather you want to make sure that you move the focuser enough to definitely eliminate any problems with backlash. If you forget to have a decent amount set for backlash you might find that your autofocusing seems to make no sense - I have been there and I have done that. I refused , however, to buy the T-Shirt, since the ones they had in my size were a colour that would, in my view, have clashed with my hair (especially now that I have had my highlights refreshed). Steve
  9. Thanks Rich.
  10. If I recall this is at least your second foray into poetry in recent weeks. Is there anything we can do to help?
  11. Told you it was a pterodactyl....
  12. The beak:
  13. Thanks everyone for their kind comments. Yikes - is this the SGL equivalent of a 'Twitter fight'? I must say that it would seem odd to me to have the Pelican Pterodactyl any way up but upright, but I am willing to experiment. Sara: did you mean beak up: or beak down? 'Original' for comparison - And what do folks reckon to the colours in the new version?
  14. What I found was that I would focus in Lum (get value X); focus in (say) Ha (get value Y); focus in Lum again (get value Z). Sometimes Z did not equal X!!! So you do need to be careful. However, the control is so fine with the stepper I doubt that the few points difference between X and Z was significant. I did 5 'pairs' of Lum/Ha before deciding what my Ha offset was. And so on through all the filters.... It may take a couple of nights. But hey - we are 'testers' not imagers aren't we?
  15. Back in early June, I collected 5 and a bit hours of Ha using my dual WO Star 71 Rig - https://stargazerslounge.com/topic/295500-pelican-in-ha-first-real-test-of-dual-rig/. The plan was to collect 5 hours of each of SII and OIII to go with the Ha. I got 3 hours of each (simultaneously) by the end of June and since then the weather has not played ball. So, I decided to go ahead and process what I had. Those Star 71s give a good wide field. This is WO STar 71 x 2 Moravian G2-8300 x2 Mix of Astrodon and Chroma filters Ha 5hours 20 minutes OIII 3 hours SII - 3 hours That's 11 hours 20 mins total: