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_dslr_mirrorlesss_winners.thumb.jpg.9deb4a8db27e7485a7bb99d98667c94e.jpg

philhilo

Members
  • Content Count

    59
  • Joined

  • Last visited

Community Reputation

6 Neutral

About philhilo

  • Rank
    Nebula

Profile Information

  • Location
    West Midlands, UK
  1. Argh!!!!! All set up and a fleeting shower just rained nicely on my kit including all over the objective lens (was imaging M31 just about on the zenith). Brought it inside, any suggestions on quicker methods of clearing the lens than watching it slowwwwlllllyyyy dry off now the skies have cleared.....again? Gentle mopping with cotton wool, loo roll?
  2. From experience another reason DSS can baulk at a set of subs is having one that is radically different to the others - it has happened to me more than once when I have shot multiple targets and got an image into the wrong batch. DSS then only processed a few of the subs, got to the different one and didn't do the rest. Very baffling till I went through the subs when more awake!
  3. Thanks. I am in Solihull. I want an Ha filter asap but dont think I can justify the others whilst running a DSLR, and that's another £130 which will ultimately go towards a dedicated astro cam. Completely understand not wanting to split them up. Good luck with the sale.
  4. I definitely don't waste clear skies on darks, or I get to a point where I can do no more and leave it with APT to finish up the darks - come back in the morning. Had wondered about light getting in around the mirror of the Newt, I tend to chuck the scope coat on so that's going to be pretty dark combined with the lens cap. I am trying to build a darks library but have just changed DSLRs so its start again time.
  5. Jeepers had me going there for a moment. Definitely a beginner but thought I had that covered off!
  6. I do dither but was beginning to wonder via research if there was any point in the bias with dithering. I did read that one set was enough. Flats - I have already figured that they aren't going to change unless the camera orientation changes. My thoughts around darks makes me wonder if the time of exposure is in fact irrelevant - is it just temperature critical, the temperature being a factor of the time/ambient. I did read that sensor temp can lag a long way behind the temp read out which is in fact the chip temp. Also use of warm air blowers used to bring the whole lot UP to its likely final temp. I can see the logic in this but wonder if in a situation where time is of the essence if its benefits are more than negligible.
  7. I should set up my kit list, however a lowly Canon 650D, recently modded - hooray, and added an IDAS LP D2 filter and wehay the nebula are actually there, not just 'fake news'. Yes I was beginning to consider storage - huge piles of calibration frames that are surely redundant once a master has been made (I am building a calibration library but researching furiously before I bin stuff).
  8. Hooray, and apologies for the panic. Looked back through the files and discovered there was a shot of M45 in the set. I shot two targets last night, but not sequentially as I was cloud dodging. When I looked at the files APT had labelled them in such a fashion that they went into the folder interleaved, thus I had to sort them visually off of small tiles (whilst doing breakfast, fielding small children etc). During that process one ended up in the wrong folder and that is what lead to DSS rejecting 90%, rather than rejecting one outlier as you might expect. So moral of the story is when shooting multiple targets check the files very closely and DSS does not always respond in an expected way to bad data in. Thanks again everyone for their help, cheers.
  9. Thanks for that. I wondered about that (been there ages ago and it was a focus issue, but this looks fine - just done M45 from same session and no problems but obviously much higher in the sky out of the murk), with the detection at 20% most were 50-70 stars detected, and some 250. Now I have pushed the star detection threshold down to 10 or 5% and it is picking up 250+ stars, although looking through the files 6 or 7 have 3 or 4 times that amount. It is still rejecting the bulk of the subs. Is it processing those and rejecting the others, do I need to split it into 2 batches? Can I see which subs it is rejecting and which it is processing? Cheers.
  10. And my second question, why does DSS sometimes throw out perfectly good looking data? Thought I was having a great night and with over 2 hours of the Horsehead and it only wants to use 6 or 7 of the 44 subs, and they look fine, seeing was pretty grim but that's not been a problem before, baffled.
  11. Using DSS is there a way of telling it to reuse use masters it has already made when reprocessing data? Such as the master flat, or master dark, rather than it churning through everything when you redo a set of lights?
  12. So to closure. Had a 30 minute clear sky/availability slot tonight, and threw everything into checking the new scope/flattener/focus issue - family/work/life permitting. Standing staring at the darkening sky straining until I could make out polaris - pa. Next - capella - 1 star align and get an eyepiece in there and it was looking sharp so the OTA is OK. Quickly switch the flattener and camera in - gutted no focus, aha, haven't taken the nosepiece off the flattener. Fumble fumble, tough to dismantle as several adapters are very thin or hidden and I screwed the whole thing down hard to take the flex out. Surrounded by expensive bits of kit perched on slopey wet plastic as I wrestle the next bit off. At last nosepiece out and reassemble. Argh, mount swivels whilst screwing the whole assembly back on to the drawtube. Quick realign to Capella and manual focus as no Bhatinov for this yet - it looks OK on the camera at x10. Fingers crossed. Then hook up the laptop to mount and camera, and GOTO M31 (I know should have stayed with Capella to check focus further), and a quick 30 second image whilst looking at watch counting down the minutes, and...….its looking OK, the focus seems OK, at last after weeks of faff and many £££ it looks OK without getting up close, hooray! After that a series of high ISO images to try and get decent centring before realising that the lack of balancing was killing the tracking (I normally massively overload the mount with a 200mm reflector and DSLR and guidescope and telrad but have it nicely balanced and it guides just fine, so figured it cant be that bad with this little thing, wrong!) and I was out of time - and the fog rolled in 5 hours earlier than forecast. I had hoped to put up a nice image of M31, however, below is the single unguided 30sec frame of M31 that the little WO 66SD finally delivered, and I think it is OK considering the tracking was all over the place, (ignore the colour, haven't yet sorted processing images from the modded camera). As my son said, "Dad, why do you choose to do things that are so hard?" Thanks all, merry Christmas, and clear skies!
  13. Apols for not picking this up. Cheers for the pics. Where are we at with the story - well, I got the SCT to M42, then another adapter to take it to the M48 onto the OVL flattener (sans nosepiece) and then the T mount onto the Canon adapter and Canon.....phew. Ist up, the SCT female onto the male drawtube, epic struggle to get it on more than 1/2 - 3/4 thread - not good. Looks like the new threads messy but wouldn't have expected this much of an issue. Everything else OK. Now lots of play in the optical train. Tightened up everything until its just the SCT joint loose. 1st attempts at focus purely through the viewfinder and I am not sure we are there. Much better but not pinpoint. Had another look later - maybe it hadn't cooled down (my 200PDS is very good natured in that respect, not often a dew issue and seems to reach ambient by the time I am organised) - and it was an ice cube! I don't really want to throw more money into dew heater when I am not sure if the OTA is a goer. Still to run it through the laptop as a double check but not optimistic, had hoped to get a shot at the moon during day time, starting with an eyepiece without the flattener, then add flattener, then camera. Looks like might be a window Tuesday night. Fingers crossed.
  14. Ta-da, the nosepiece came off the OVL flattener (vice + silicon oven glove + filter wrench) to reveal M48 female threads. Studying the RVO catalogue it appears that I can get an SCT female to T male (10mm optical length) then a female T to M48 adapter (0mm optical length). E-mailed RVO to see what they think of this plan. I see that Blue Fireball in the USA do single SCT to M48 adapter so that's a longer time option - many more clear nights with the new OTA leering at me. Here's hoping it all happens before M31 disappears for me. Thanks again all. Phil
×
×
  • Create New...

Important Information

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