http://www.astrobin.com/users/orion69/ TS 150 mm APO Triplet, Feather Touch 3.5" focuser, Micro Touch Focusing System CGEM on custom made platform Atik 383L+ mono, Atik filter wheel, Baader LRGBC + narrowband filters SX Lodestar + TSOAG9 Dew-Not heater
Quote:I'm only guessing here, but I would say that 8" Istar f12-f15 would visually blow away TOA130 for planetary (or any other 130mm APO).
Takahashi SKY90 , Vixen SP
Istar 127mm f/8 Achro , HEQ5 on TV Gibralter
C9.25 XLT carbon fiber , HEQ5 .
Quote:Not an easy call , Achro's are more natural .
Quote:Not an easy call , Achro's are more natural .
Kmart 40mm-Thanks Mom|Jason60mm-Thanks Dad|C80SS-Thanks Wife|C90|C102|C6XLT|AP130EDFGT|C-11XLT EQ-2|EQ-3|CG5GT|Mach 1 & Eagle "For once you have tasted flight, you will walk the earth with your eyes turned skywards, for there you have been and there you will long to return".-Leonardo da Vinci "We're all in the gutter, but some of us are looking at the stars."-Oscar Wilde ~RIP Dad, you were my best friend...Godspeed!~
Quote:Quote:I'm only guessing here, but I would say that 8" Istar f12-f15 would visually blow away TOA130 for planetary (or any other 130mm APO). What would "blow you away" is the scope that was somewhere between 8 and 10 feet long, the mount required to handle the scope and the wide range of eyepieces heights, and it would still only be an 8 inch scope.Jon
Quote:...have you considered the size, weight, and cost of a mount capable of supporting a long focus 6" or 8" refractor?
Shane in black-zone New Mexico'Fracs, Maks, Newts and Schmidt-Newts, 3.1"-10", f/4-f/13. Alt-az and GEMs.
Quote: The detractors of these long f ratio achros have short memories. Achros participated in pushing back the frontiers of astronomical science up to and including the present times. What have apo's contributed? Jim
Joe (quote)"That does it! Next Big Bang, someone has got to rethink this gettin' old business!" Joe Daugert -------------------------------------------------- >>>>>>>>>>>> ISTAR Scope Club <<<<<<<<<<<<
Quote:Here is what I was told by Barry Greiner of D&G Optical (a top US achromat manufacturer)which I think is a good rule of thumb and latter confirmed by my own field experiences...an achromat that is one inch larger than an apochromat will show as much planetary detail as the smaller BUT with chromatic aberration (CA,the purple blur) that may be bothersome to some people.
Quote: I never suggested an achro is THE cutting edge of anything only that they still contribute to science and my question suggests that apo's don't.
It was a 20x power, 0.3° field of view telescope, sporting a singlet objective stopped down to 15 mm that profoundly changed our perspective on earth's place in the universe.
I mostly enjoy small, fast, and (ultra)portable glass: Bushnell Legend 8x42, Pentax PCF WP II 20x60, MiniBorg 60ED, ST-80, EON-80, ST-120, 6" StarBlast.
Quote:Could I match the detail shown in the TOA130 with a 152mm f12 - f15 Achro or maybe an 8" achro like Istar produce?
Whenever I have come into large sums of money in my life, I always put half of it aside to spend on fast cars and the pursuit of loose women.
I put aside the other half to spend frivolously.
16" AstroSky F4.5 C/W Skycommander, TEC 140, 6" F8 Edmund, 120 Skywatcher F5 SW EQ6 AP SPL 5mm Carl Zeiss Jena .965 6,10,12.5,16,25, Pentax 3.8mm XP, 7mm SMC, 7XW, 10XW TMB SMC 8mm,TMB Planetary 2.5,6, TV Smoothie NJ's Plossls, 14 Delos, Nagler 20T2, WO 4,28 UWAN, Orion Zoom 7.5-22.5, BGO 9 Binoculars Pentax PCF 7x50, SPACE, "A PORTRAIT OF PERFECTION!" Tony M
Quote:Levine, How well can you bring in gobular clusters with yourfast F/6 210mm? Thanks De Lorme
Quote:Quote:Not an easy call , Achro's are more natural .You are kidding, right?
Quote:I don't know that a lot of detail is lost on a planet because of some CA being present. If the optics are of equal quality I would think that two scopes of the same diameter would perform almost the same. The problem is that not many manufacturers put as much effort into their Achro's as they do their APO's. They tend to not only correct the CA but correct other aberrations as well.The telescopes that discovered most of the stuff we look at were well made Achro's.
SLAP Observer --- TMB130SS, SV102V(LOMO Lens), SV80ED Deluxe "The only thing necessary for the triumph of evil is for good men to do nothing." -- Edmund Burke. "People sleep peaceably in their beds at night only because rough men stand ready to do violence on their behalf." -- George Orwell "The measure of a man’s greatness is not determined by what he accomplishes for himself, but by what he accomplishes for others.” -- Some Bald Guy
Quote:The telescopes that discovered most of the stuff we look at were well made Achro's.
Nine telescopes of a diverse nature. My Web Site Cosmic Cat: a children's book about astronomy for iPad. English Lessons for Amateur Astronomers
Quote:If the optics are of equal quality I would think that two scopes of the same diameter would perform almost the same.
Quote:Quote:Quote:Not an easy call , Achro's are more natural .You are kidding, right? I don't think so. What's interesting is that he attests it not his opinion alone with the apo showing a clinical view and the achromatic a more natural view. I'm curious to know what this natural impression consisted of. It's an interesting take. CA had to be seen but despite that a natural quality over the color free image was appreciated. I'd like to hear the details - if he's only respond. The notion is interesting and at no swipe to the apo.Pete
Quote:Purple and black together are among the most beautiful color combinations there are. I prefer achromats and actually love the "false color." Maybe I should add an achromat to my signature to make this sound a bit more believable.
Quote:... Have you the cash laying around to chase that extra resolution? Go for it. Otherwise, prepare for a little compromise on the CA issue. And to repeat what was said, there is only a handfull of objects out of 10's of thousands that this is even an issue. If your concentration is on those objects then put your money into that chase. Jim
Do I detect something in your voice that says I'm in disfavor with you?
-Yes. I wish you were dead.
Clear skies - Jim Crazy PNW imager !
A-P Mach1 on 12" concrete pier - ROR structure.
Tak FSQ85-EDX, Tak FS-128. Orion 8" f/3.9 w/MoonLite motorized - MPCC MkIII CCD:
SBIG 8300M/FW8, Astrodon 36mm LRGB, 5nm Ha, 3nm SII, OIII - Canon EOS 6D unmod SSI3, SSAG,
Skytools3pro, MaxImDLpro, PSCS5, PSPpro, TheSkyX, TheSky6, BYE, StarTools
Orion XX14g -for visual- diags, ep's, accy tubes, Binocs .