Jump to content

Stargazers Lounge Uses Cookies

Like most websites, SGL uses cookies in order to deliver a secure, personalised service, to provide social media functions and to analyse our traffic. Continued use of SGL indicates your acceptance of our cookie policy.

sgl_imaging_challenge_banner_solar_25_winners.thumb.jpg.fe4e711c64054f3c9486c752d0bcd6f2.jpg

long_arms

Members
  • Content Count

    599
  • Joined

  • Last visited

  • Days Won

    2

long_arms last won the day on August 1 2013

long_arms had the most liked content!

Community Reputation

364 Excellent

6 Followers

About long_arms

  • Rank
    Proto Star

Contact Methods

  • Website URL
    http://flic.kr/ps/2o7bHL

Profile Information

  • Gender
    Male
  • Location
    Basingstoke
  1. Ha I did google this out of interest, all those crushing/bending penny machines at tourist destinations springs to mind. Can't believe its enforced. However to remove any doubt, it was only paint. I have now cleaned the 20p clean and the Queen looks as good as ever! No tower for me just yet.
  2. Small splodge opposite the focuser of the 200p dobsonian. Pointed at a light source to attempt to illuminate it. The inside of the telescope seems very black until I illuminate it like this. Interestingly I can find an angle where the paint appears "lighter" than this. Its hard to get a photo of.
  3. I've seen mixed things about Black 2.0, apparently it had the usual tendency of getting slightly lighter as it dried. The video I posted shows comparison between Black 2.0 and Black 3.0 quite well I think. From this article: https://www.fastcompany.com/90300113/move-over-vantablack-you-can-now-buy-the-worlds-blackest-black-paint "His first version, Black 2.0, wasn’t quite as black as Vantablack, since it only absorbed 95% of the visible light (Vantablack absorbs about 99%). Now, Black 3.0 is out and available on Kickstarter for about $32 per 150ml tube. According to Semple, it is the blackest, mattest, flattest acrylic paint available on the planet, capturing up to 99% of all the visible spectrum radiation. The paint is based on a new pigment called Black Magick, whose exact composition they aren’t disclosing. Black 3.0 is made up of this pigment, combined with a custom acrylic polymer. Semple and his colleagues claim that the polymer “is special because it has more available bonds than any other acrylic polymer being used in paints,” allowing more pigment density. The paint is then finished with what they claim are new “nano-mattifiers,” which remove any shine from the paint. Unlike Vantablack, the resulting paint is soluble in water and nontoxic" Thankyou for your feedback on flaking! Before I paint the drawtube I will certainly check this out. ?
  4. This is a good shout, I have an IR742 Pass filter somewhere, I'll try and get a photo through that. The small amount of dried paint on paper, is now making everything I can find look positively gray!! I'll see how easily it flakes when its dried on the steel tube of the telescope.
  5. Tried to think of a fun quick test to document this afternoon, previous little tester on less metallic object is unbelievable to be honest. So, very shiny coin with grazing light and lit from above also. Whilst drying, as you can see its a thin single coat (not simply "filling" in the shape) Finally, even on a challenging shiny object with light shining on it, it makes it essentially 2D.
  6. Hello, It's been a long time since I've posted in this forum, anyway I've picked up a Skywatcher 200p F/6 dobsonian as a DIY project whilst I continue to work on a new telescope from scratch, (I've started to grind the mirror). I'll be making improvements to this dobsonian as a project and learning experience, I've already got a temperature controlled fan which has a probe that can measure both mirror and ambient temperature. I'll be measuring the primary mirror with my in progress Foucault/Ronchi/Bath Tester when that's finished in the next couple of weeks, may even refigure it depending on results. But I'm most excited about this right now. The blackest Black Paint as an alternative (hopefully better alternative) to flocking! This stuff is seriously black and flat, I backed it on kickstarter and received 3 bottles along with goodies. I plan on painting the area opposite the focuser, area around the primary mirror, inside the focuser drawtube, potentially the secondary mirror holder and edge of the secondary also. It's a shame I don't have any flocking to compare it with but it looks incredible. This video shows just how impressive it is (moreso than my little tester I've done). https://www.youtube.com/watch?v=uJIIzcbRD9w I'll try and get some decent before and after pics. Dan
  7. Hi, I saw in the asi174 thread you were using it for ISS imaging. I'm considering buying one to do the same thing, but I'm torn between the 174 and the 178. Do you think the global shutter on the 174 makes a big difference?

  8. I need to stop. But I couldn't resist. Last one I swear. This one is of Mr Percy Wilkins and his amazing hand drawn maps of the moon from 1953. Never heard of him but now I have to find his maps.
  9. The British Pathe Youtube channel is incredible. You could quite easily lose a few hours trapped there watching old videos. If you search for telescope or astronomy there alone it comes up with dozens of archived footage. I won't post them all. Here's a bloke in 1942 with his homemade 14" Newt. Even made the screws !! Thats keen. Is it the Earliest footage of amateur astrophotography?
  10. I managed to stumble onto this old film from 1960 on Youtube. It seems "Cox, hargreaves and Thomson Limited" used to grind mirrors in an old air raid shelter ! Funny film. I was curious and found this website about the tunnels! http://thetimechamber.co.uk/beta/sites/deep-shelters-air-raid-shelters/coulsdon-deep-shelter-surrey Be good if one day some ATMs get permission from the council to use them for the same purpose again.
  11. Hello, Unlike me, there are some real experts on this forum and I hope they respond to this thread . I will however, throw in my 2 cents in the meantime. I could be wrong, but the massive difference in the airy disk inside and outside of focus is normally a pretty good indication of spherical aberration. In this case youve got very strong rings inside of focus and for want of a better word; mush, outside of focus. This surely indicates Undercorrected Spherical Aberration. Dan
  12. No problem ! The Normalize Histogram is actually quite useful for finding the best exposure settings to be fair. You can play with gain, shutter speed, exposure etc. I.e Sacrifice some gain for a higher frame rate and compare against regular settings easily because the brightness of the two stacks will be the same.
  13. The 'Normalize stack' setting on the Stack Options side of the main window. Just below the 'Frame Percentage to Stack'. I check this and adjust the percentage to whatever brightness I'm after. Dan
  14. My camera came today also No duty to pay either which was great. Works well with my laptop. It doesn't come with a suitable lens (presumably because of the larger sensor) so I have only been able to see a dark frame (The CS lens that comes with the ASI120's won't focus). First impressions are extremely low noise even with the gain pushed to the max. Certainly seems better in this respect compared to the ASI120's. Finally however it does seem to get warm quite quickly regardless of settings. Sure its nothing to worry about just something I noticed. Dan
  15. I already have the ASI120MC-S and with my relatively new USB 3.0 laptop I have gotten some pretty great frame rates. The bottleneck imo is the Hard disk though. At the end of the day would I get this camera if it was USB2.0? Yes. Definitely glad its USB 3.0 though for those ISS chasing moments ! With regard to deep sky. I took this with my ASI120MM+colour filters. Unguided. Lots of short frames. Through my 200p/heq5. I think it worked quite well. Guided would be better but my guide camera was taking the light frames I reckon the ASI174 will be much better for deep sky so I'll no doubt give it a go. Dan
×
×
  • Create New...

Important Information

By using this site, you agree to our Terms of Use.