Binos: APM100 | Obie 20x80D3 | Resolux 15x70, 7x50 | Nikon AE 12x50, 7x35 | FMT-SX 10x50 | Canon 10x30 | Vanguard ED 8x42
Mounts: AVX | Orion Paragon | Tecnosky eLLe
Telescopes: XT8g | AT6RC | Onyx 80EDF | 102GT | ST80
1.25" EPs: Hyperion 8, 17mm | ES68º: 20, 24mm | ES82º: 4.7, 6.7, 8.8, 11, 14mm
2" EPs: Meade 5k 82º: 24, 30mm | ES100º: 5.5, 9, 14, 20mm
Quote:Thinking of getting one of these scopes on the new VX mount. I want to have my first "serious" scope to be something that:a) Provides good visualsb) Is good for imaging DSOs, the moon, and planets (priority in that order).c) No more than $2k for scope and goto mount.I considered a mounted newt, but realized that all the added weight would require a much sturdier and $$ mount, and would be much less convenient to move and store than a SCT. Someday I hope to add a 10-12" dob as a dedicated visual scope. In the meantime I need an all-rounder.Obviously the bigger mirror can collect more light. But they are both f/10 or f/6.3 with a reducer. Does the difference impact astrophotography, such as the FOV you can get with prime focus? If so, which of these two is the better choice? What are the tradeoffs?
http://claudedesrosiers.smugmug.com Twitter : Fogboundturtle's on Twitter Scopes: Celestron C8 SCT, Meade 127mm ED Triplet Mounts: HEQ5 PRO + SyncScan Version 3.24 Camera : Canon 5D Mark III unmodified, DMK31 , STF-8300 Pro Package plus
ROR Observatory Levenhuk 8" carbon fiber RC, Astro Physics CCDT67 Astro-Tech AT8IN w/Moonlite, Baader Mark III MPCC Levenhuk 80mm triplet, Astro Tech 0.8X reducer/flattener Celestron CGEM DX w/HyperTune STF-8300M SX 7 position 36mm CFW Astrodon 5nm H-alpha Little Piney Observatory
Quote: For true deep space stuff, most people want 3-5 minute (or longer) subs
Quote:If you want to image primarily DSO then SCT is a bad choice for you. You want a very wide refractor and yes the F ratio matters. The faster your scope is, the more light your camera will pick up.
Quote:Even the 800mm focal length imaging newt was challenging for us as beginners
Quote:So why not just collect 10*N 30-second exposures and sum them together instead of N 300 second exposures? What's the difference?
Quote:What makes 800mm challenging?
Quote:The difference is you will want 10 (or more) 300 second exposures on a lot of objects to bring out the most detail.
Quote:Why? In my line of work we routinely collect digital data with poor signal/noise ratios but overcome it by doing dozens of scans and summing them together. With N scans, the signal scales by a factor of N, while noise scales only as sqrt(N). So why not just collect 10*N 30-second exposures and sum them together instead of N 300 second exposures? What's the difference?
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 .
Quote:Quote:The difference is you will want 10 (or more) 300 second exposures on a lot of objects to bring out the most detail. I get that, but why not 100 30 second exposures instead? Tedium? The EOS software can bet setup to trigger the shutter ever ~30 seconds for infinity if you want (I've used it for time lapse before). I'm sure I'm missing a basic point, having never done astro imaging before.
GM-8 GII (soon w/OPWB) ; Orion Sirius w/EQMOD
Orion 80ED; AT72ED; AT6RC
Atik 314L+; Atik 420C
Moonlite Focusers, Moonlite stepper motor
Astrodon 5nm Ha, LRGB; Baader OIII, SII
Starlight Xpress 7x1.25" FW
Sequence Generator Pro, PinPoint, PixInsight, PS CS 5
Quote:Quote:Even the 800mm focal length imaging newt was challenging for us as beginnersWhat makes 800mm challenging? Imaging newts are like f/4, right? Shouldn't that be plenty fast and wide for imaging? I originally was leaning towards an f/4-f/5 8" or 10" newt on an EQ as a good all-around option. Ultimately the weight and overall encumbrance of such a package got me looking at the SCTs instead.If I had a refractor as my "one-scope", I fear I'd be missing out on aperture for nice DSO visuals. Realistically I'll eventually end up with all three (SCT, Dob, ED refractor) so this really boils down to the question of which one to get first. If you had to live with *just one* telescope for, let's say a year, which would you choose and why?
Quote:Quote:If you want to image primarily DSO then SCT is a bad choice for you. You want a very wide refractor and yes the F ratio matters. The faster your scope is, the more light your camera will pick up.Remember, I'm looking for a good all-around "one scope". I understand that there is no such thing as a perfect scope and I'm willing to make tradeoffs. I know that I won't get the big DSOs like Andromeda to fit in the FOV of an SCT. But there are plenty of others to look at and image that are much smaller. I've seen some more than adequate (to my untrained eye, anyway) photographs of smaller DSOs on the DSLR forum coming off C6 SCTs, for example. What's wrong with those?I guess it comes down to what tradeoff I want to make. I could get a wide, short refractor for FOV/brightness (which lends itself to astro-imaging more), or go for a larger aperture SCT (which lends itself visual astronomy more). Am I thinking about that correctly?
*Good is stronger than evil *Love is stronger than hate *Life is stronger than death Astrophoto Gallery:http://www.astrophotogallery.o...g-the-night-sky.html