I wander’d off by myself,
In the mystical moist night-air, and from time to time,
Look’d up in perfect silence at the stars. -Walt Whitman
ES f/7 102mm ED triplet APO CF
iOptron f/12 150mm MCT
Meade f/10 203mm SCT OTA, f/6.3 reducer
Celestron AVX mount
Orion f/12.1 127mm MCT / Celestron SE mount
Astro-Tech f/6.5 AT65EDQ Astrograph
Orion SSAG/mini guide scope
AT 50mm helical focus guide scope
Orion SSAIO camera
Canon T3i DSLR
Backyard EOS; PHD guiding
Baader Hyperion III 8-24mm zoom
ES82 4.7mm, 18mm
Celestron Nexstar 8SE, C6, TV Geniesis, Orion 4.5 Starblaster, Coranado PST, Discovery 8" DHQ, Orion 90mm F10.1 Binoculars:Nikon 7x35,Canon 8XIS, EP's 8 to 24 Hyperion, 2 TV zooms 55,32, TV plossel. 24,19,35 Panoptic, 16T5,11T6,7T6 and 5T6 Nagler CG5GT,TeleVue systems mount on ash tripod.
Quote:I have an f/5 C8-Newtonian that I would like to improve for my visual use. Is a coma corrector the accessory I'm looking for ...
First and foremost observing love: naked eye.
Last but not least, telescopes.
And I sometimes dabble with cameras.
Quote:Is there a specific problem that you're trying to correct?
Quote:When it's accurately collimated it is very sharp in the center 30% or so of the field of view. I've recently been using a couple of used 65-75 deg ep's and I am very aware that the stars/objects near the edges of the fov aren't nearly as sharp and sometimes can see the hair-like coma effect.
WO Megrez 120 ED on GP Mount
WO ZenithStar 80 ED II on Porta II
10" Meade LightBridge/Paracorr
Orion ED 100 on Polaris Mount
Astro-Tech 8" f6 Dob
Bushnell Ares 5
Meade 226 2.4" f11.7
SpaceScope 2.4" f15
Quote:Quote:Is there a specific problem that you're trying to correct? When it's accurately collimated it is very sharp in the center 30% or so of the field of view. I've recently been using a couple of used 65-75 deg ep's and I am very aware that the stars/objects near the edges of the fov aren't nearly as sharp and sometimes can see the hair-like coma effect. I would like to have the entire wide angle fov appear sharper.
Quote:The big question is always, what eyepieces are you using?So... If all that is confusing, I offer you this: I see you are in Orange County. If you ever get down my way to San Diego, I do have a Paracorr and a variety of eyepieces, I even have a 8 inch F/5 Newtonian... You could see what coma looks like, astigmatism, field curvature... I could see what I think is going on with your eyepieces, with your scope.Jon
Quote:At f5 coma could appear but should no be to bad. most coma correctors are 2" and not cheap. Try with different eye pieces. some show less coma than others. Don T.
Quote:I've read good reviews about Explore Scientific 82 deg series and, at $99, are within my budget. Would be interested to hear what you (and anyone else who's reading) think.Thanks, Richard
10" OO VX, 6" iOptron Mak-Cass, Orion 100ED
Quote:...For the price, they are a very good value, everyone I know who has tried them has a favorable impression of them. They work very well in F/5 and F/4.5 telescopes too.Taras
Present gear: 16-inch f/4.5 Dobsonian 50mm straight through-finder Green laser pointer 26mm, 32mm, and 38mm 70 degree field EPs 4.7mm, 14mm and 18mm 82 degree field EPs 8mm, 17mm, 21mm 68 degree field EPs 2X 2" Barlow Tirion star atlas (white stars, black background) hand-laminated Megastar Editor & co-founder Las Vegas Astronomical Society Observer's Challenge To nudge or not to nudge, that is the question www.fredrayworth.com
Quote:If you want to fork out maybe the price of your scope, or even more, just to get a slightly flatter field, more power to you.That's just my two cents.