Some astro accessories

Stuff is expensive, but preconceptions aside, astronomical equipment doesn't always cost an arm and a leg. Also, optics can last forever if treated well. This stuff has embellished my telescopes for some time.

Plössl eyepieces
  • 40 mm, 26 mm, 10 mm, 7.5 mm focal lengths
  • No-name, yet high quality, eyepieces from Teknofokus
  • These are truly excellent eyepieces and have served me a long time with my 200 mm telescope
  • Celestron achromatic Barlow lens—for those select evenings when the atmosphere seems to have disappeared. Saturn at 350×, yum!
  • But once you've looked through a Nagler, Plössls just seem so... narrow.
TeleVue eyepieces
  • 27 mm, 24 mm Panoptic
  • 13 mm Nagler Type-VI
We all know the name TeleVue and drool at Nagler eyepieces (well, nowadays we drool at Ethos eyepieces). After all the time and expense I put into my new 400 mm telescope, I decided to complement it with only the best.

The 27 mm Pan is maybe a bit too wide, showing just too much coma in an f/4.5 Newtonian scope. The 24 mm shows less coma, and it comes in a 1 1/4" barrel (the 26 has a 2" barrel), and therefore fits better in my filter adapters.

  • Astronomik 2" O-III visual filter
  • Astronomik 2" UHC visual filter
  • Both in their own 1 1/4" to 2" adapters
Most my eyepieces (all except the 26 Pan) are 1 1/4" size. Therefore it may seem a waste of money to buy 2" filters. But in our arctic climate, attaching expensive filters to eyepiece threads with fingers frozen numb is something of a hazard. It is so much more convenient to leave each filter on its own dedicated 1 1/4" to 2" adapter. Not only is changing filters a lot easier, but eyepieces can likewise be exchanged to change magnification, without having to move the filter from one eyepiece to another.
  • Lumicon 1 1/4" O-III—my old deep-sky filter. After 10+ years of use, it has developed a spotted appearance—that can't be good.
  • Baader 1 1/4" Neodymium filter—Very good for improving contrast on Jupiter and Saturn! (Also great fun for eyeballing daytime surroundings, some shades of red are strikingly emphasized!)
  • 1 1/4" Neutral density lunar filter, 2% transmission
  • 1 1/4" #21 orange filter, which I bought once when Mars was in opposition (not that effective, really)
Laser collimator
  • Really the easiest way to collimate a newtonian
  • Funny, inside this contraption there is a laser pointer! Those things must be cheaper than the laser diodes they contain!
Home-made Telrad copy
  • Ever since I built myself a Telrad-clone, I've never wished for a finder scope, although I once had a very good one (home-made also) on my 200 mm scope (before rebuilding it from aluminum)
  • The optics comprise a microscope slide, a lens, a first-surface mirror, and the bullseye pattern photographed onto black-and-white negative film, illuminated from behind with an adjustable red LED
  • I rarely make use of the bullseye ring pattern, so a red-dot sight would do almost as well

I have gone through several pairs of cheap binoculars, some bought second-hand, some bought new, some quite decent for their price, some optically beautiful but utter plastic rubbish mechanically. Some I have purposefully destroyed to obtain optical parts, some have broken down because... because they are utter plastic rubbish mechanically. The optics are glass, of course. And, surprisingly, even the cheapest plastic rubbish 7×50 binos that I've used have been optically quite decent! I guess it's not rocket science to make an optically decent pair of 7×50s, but I can't say the same for most 10×50s I've tried. Strange.

Finally I paid up and got myself a pair of vintage Carl Zeiss Jena Binoctem 7×50 binoculars, made in East Germany. Based on the serial number, they were produced in 1983 and they do obviously have multi coated optics. Yea, legendary Carl Zeiss glass from Jena, DDR. Mint condition, complete with ugly faux leather case. I swapped the original masochist neck strap for a padded one, and I love these. Just watch out for fakes when bidding on eBay, and buy from a reputable seller.

Since then, I have also obtained a nice pair of mint condition ЗОМЗ БПЦ (ZOMZ Zagorsk "BPC") 7×50 binoculars, made in the USSR. The optics are tack-sharp, but the focusing mechanism is waiting to have its authentic Soviet all-purpose grease cleaned out and replaced with something that actually enables the parts to move. (I have a tube of Synco Chemical Corporation Super Lube in-shelf for that purpose. Many astro forums rated that stuff above generic lithium grease, especially for use at below-freezing temperatures. The manufacturer specifies it down to −40°C.)

Antti J. Niskanen <uuki@iki.fi>