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.



  • Content Count

  • Joined

  • Last visited

  • Days Won


Everything posted by Uranium235

  1. Quick update on my quest to collimate via a camera. Given up on the pinhole concept for now, as I spotted a super cheap 8mm CCTV lens (cs mount) that will work with either my QHY5 or 178mm camera. I can just pop that on and collimate / tinker until im blue in the face
  2. Well, I gave it a go.... Good news: I got an image at the right distance from the pinhole. Bad news: The image is not yet sharp enough to use, I was testing it on a barcode. Still too blurred, for macro (what this essentially is) the hole needs to be >tiny<
  3. Yeah, just looking ar a few examples done with a dslr. Its possible but to improve the sharpness I need to make the hole smaller. I will do a few experiments when I have a spare evening this week
  4. Just putting my thinking cap on about something - namely how to collimate this (and other newts) with the imaging camera in place. Previous thoughts about this always involved putting a short focal length lens where the filter would be... however... today I had another idea. Astro cameras are very sensitive things and can easily cope with a high f ratio. So, what about doing away with the lens concept and using a pinhole instead? It's cheap, anyone can make it, and with a few careful calculations should deliver the right focal length required for taking images of the secondary mirror. Daft idea? Maybe... maybe not
  5. I guess if its just for the heater, you could try a lithium pack with a 12v output, maybe something like this? https://www.amazon.co.uk/TalentCell-Rechargeable-6000mAh-1a4XT9/ref=sr_1_7?keywords=12v+power+bank&qid=1581114689&sr=8-7
  6. If i didnt know better, but whoever made that adaptor probably got the idea from here...lol.. I built my mod a good 4 or 5 years ago:
  7. I was pretty lucky in that mine rotated to portrait (with respect to the focuser) right at the point where the threads started to really tighten up. If it was to far before that I'd either have to come up with a different configuration - or take a chance and tighten it up as much as poss until the right camera rotation is achieved.... but the big danger with that is a cold-welded thread (never much fun to try and undo). Thats why I apply boot polish to my threads to reduce or prevent binding when doing things up fairly tight.
  8. Many apologies for the late(ish) setup for this, but (yay!) its now time for the 2019 imaging showcase!! Please use this thread to showcase your best images captured during 2019. Just one post per member but you can include up to 5 images if you want. The thread is for all imagers, both novices and advanced. Please keep details to a minimum - scope and camera possibly along with a few comments. The thread needs to be packed with images so please don't respond to the postings. The previous years showcase thread(s) can be found here: https://stargazerslounge.com/forum/203-imaging-showcase-threads/
  9. Im using the same kind of thing, but I built mine myself The only issue with this arrangement is that the camera rotation is arbitrarily set by the travel of the threads - so you dont have much wiggle room to get it right (to the nearest 90 degrees).
  10. Just rolling my 130 for just over an hour... got the MPCC spacing utterly wrong though...lol. So ive had to crop the ugly part out. 10x450 (Ha)
  11. Samyang mod now available from FLO https://www.firstlightoptics.com/adapters/astro-essentials-samyang-lens-to-m48-adapter.html Product discussion thread here: From what it seems after discussion, is that there is a good chance it will also work with the manual 85, 50, 35 and 14mm lenses (canon fit). Hopfully someone can verify this over time.
  12. That looks almost identical! You will notice that the three screws are not quite 120 degrees apart - one of them is offset by about 10deg, same as the 135mm. What it looks like is that the rear end of all the MF canon fit lenses are the same construction, just with different optics upfront (makes sense to keep production costs down).
  13. More on spacing... You can see the M48-T2 adaptor (plus delrin spacer) im using is roughly 8.5mm, and the distance from the camera T2 plate to the sensor is a whopping 35.5mm. Both add up to the magic number of 44mm, when setting up your spacings, dont forget to add distance when using filters. Example: Astronomk: +0.33mm (may not need to bother) Badder: +0.66 Astrodon: +1mm It might not seems much, but 1mm can put you well short of infinity focus. The camera im using has a mixture of Astrodon and Baader filters - slighly more complicated
  14. Okey doke, back in front of a proper keyboard now: As for the question of other lenses in the Samyang range, I have to stress that this mod is for manual lenses only - as the electronics invoved with an AF lens would simply get in the way. Now, looking a the bayonet for the 85mm Sammy - it looks like the mounting is suspiciously similar to the 135 I suspect the 50 and 35mm manual lenses would follow suit. So if you already have one of those in your box then there may be a good chance it would work.
  15. More than enough room, you can use a standard thickness filter wheel which is usually about 21mm and still have room left for whatever adaptor and extension rings you need. Always better to space it just short to start, then add a delrin spacer or two in order to get it focusing as close to infinity as possible. I'm chuffed that one of my ideas actually turned out to be useful I'm out working at the mo, but I'll fill in with more info when I get home.
  16. Quick update chaps, the Samyang mod will be available from FLO shortly.... watch this space
  17. Thanks Its the QSI683ws camera (KAF8300), and the lens was stopped down to f4.
  18. Its been a while, what with work, Christmas, and endless cloud getting in the way of things. But I've gotten a few images out of the modified lens now The only downside, this particular lens is not quite on par with the two Ive had previously - so Ive had to stop it down a bit. The following images are all fairly short runs, just over an hour for each, and absolutely no calibration:
  19. You very seldom get a flat field with a zoom lens, questionable levels of CA too. Fixed, prime lenses are always better.
  20. This is the one I used: https://www.teleskop-express.de/shop/product_info.php/info/p2742_TS-Optics-short-Adapter-from-2--to-T2-thread---Rotation-System.html
  21. Example of a dovetail adaptor: (attached to the CC via M48)
  22. Compression rings are a waste of time/money, and the clicklock eats up far too much backspace for it to be of any use to the imager. Two best ways are either screw fit, or three screws with a dovetailed 2"-T2 adaptor.
  23. Vignetting is pretty much unavoidable with the 130 (or pretty much every other telescope to some degree), depending on the size of the sensor. Same goes for coma.... BUT .... that is what flats and coma correctors are for I got the KAF8300 sensor working with the 130, but only after a few modifications to the telescope. But if youre talking about full frame as in 35mm....lol.. no chance. There are very few astrographs that can cope with that (and the ones that do cost a mint).
  24. Its not quite in true focus Dave, so there may be more to come the filters are now clean, but I didnt get a look at the sensor since the shutter was closed.
  • Create New...

Important Information

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