hoa101
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What ~600mm focal length scope for imaging
#5699547 - 02/25/13 10:04 AM
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This post could easily go in the mount or CCD imaging categories as well, so hopefully this is the right spot for it.
Anyway, I'm interested in acquiring a scope with a focal length of around 600mm for imaging. Probably 90-100mm because 80mm becomes too slow. The AT90EDT looks awesome except that it is heavy. With my current imaging gear that would be fine. My guidescope and SSAG only weighs 1.3 lb and the Canon is slightly over 1 lb.
I plan to get a CCD and filter wheel at some point in the distant future. I am worried that the Sirius won't handle the weight of a larger imaging train with such a heavy scope.
On the other hand I have heard that people image on a Sirius with a C8 SCT, which is about the same weight...
Does anyone have any advice or real-world experience that might help my decision? There are some other, lighter scopes out there as well, but the AT90 is a really good deal price-wise.
Thanks!
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terry59
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Re: What ~600mm focal length scope for imaging
[Re: hoa101]
#5699590 - 02/25/13 10:27 AM
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My Sirius images well with about 22 lbs total gear. What CCD camera and filters? That wll make a difference not only on the mount but the focuser as well. I would recommend a threaded setup instead of compression so maybe take a look at the Stellarvue options.
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hoa101
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Re: What ~600mm focal length scope for imaging
[Re: hoa101]
#5699614 - 02/25/13 10:42 AM
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I was thinking 5 lb minimum for CCD, filter wheel, and field flattener, because who knows what I'll end up with in the end. Almost 4 lb heavier than my current DSLR by itself.
I have heard on CN that the 90EDT can support 6-8 lb. Hopefully that is accurate, otherwise that would alter the decision somewhat.
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mmalik
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Re: What ~600mm focal length scope for imaging
[Re: hoa101]
#5699634 - 02/25/13 10:56 AM
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How about 530mm f/5 astrograph like this....
Some CCD consideration here.... Thx
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hoa101
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Re: What ~600mm focal length scope for imaging
[Re: mmalik]
#5699651 - 02/25/13 11:04 AM
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Yes, I know, that scope is amazing. And with the reducer/extender is basically three scopes in one. I think anyone on these forums would agree it is the holy grail of imaging refractors. However, it is almost certainly too pricey, especially considering the investment I'll have to make when I buy CCD and filters someday.
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How about 530mm f/5 astrograph like this....
Some CCD consideration here.... Thx
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Fogboundturtle
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Re: What ~600mm focal length scope for imaging
[Re: mmalik]
#5699654 - 02/25/13 11:06 AM
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How about 530mm f/5 astrograph like this....
Some CCD consideration here.... Thx
how about the new Esprit 80m Triplet + Flattener ? it will be an F5 scope and the price is 999$. Should be available next month
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hoa101
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Re: What ~600mm focal length scope for imaging
[Re: Fogboundturtle]
#5699740 - 02/25/13 11:57 AM
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Very cool-looking scope, especially at f/5. However, it's basically the same focal length as my AT65EDQ.
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how about the new Esprit 80m Triplet + Flattener ? it will be an F5 scope and the price is 999$. Should be available next month
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Fogboundturtle
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Re: What ~600mm focal length scope for imaging
[Re: hoa101]
#5699756 - 02/25/13 12:11 PM
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Very cool-looking scope, especially at f/5. However, it's basically the same focal length as my AT65EDQ.
Quote:
how about the new Esprit 80m Triplet + Flattener ? it will be an F5 scope and the price is 999$. Should be available next month
80mm @ F5 > 65mm @ F6.5
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snommisbor
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Re: What ~600mm focal length scope for imaging
[Re: hoa101]
#5699758 - 02/25/13 12:13 PM
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Best buy out there is a TV-101 or an NP-101 from TeleVue. Pretty much in the league of a FSQ106 and can be had for around 1500 for the TV101 and around 2000-2500 for a NP101 if you are patient sometimes under 2K. Remember yo are saving the cost of a FF with that scope.
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hoa101
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Re: What ~600mm focal length scope for imaging
[Re: Fogboundturtle]
#5699823 - 02/25/13 01:02 PM
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I want to point out that the title of my thread was "~600mm focal length scope..."
I really appreciate the help, but I'd like to stay on topic if possible. Thank you!
The televue scopes are definitely a consideration. I heard there was some sort of controversy about the TV-101. What was up with that?
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Very cool-looking scope, especially at f/5. However, it's basically the same focal length as my AT65EDQ.
Quote:
how about the new Esprit 80m Triplet + Flattener ? it will be an F5 scope and the price is 999$. Should be available next month
80mm @ F5 > 65mm @ F6.5
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Thomas Karpf
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Re: What ~600mm focal length scope for imaging
[Re: hoa101]
#5699835 - 02/25/13 01:18 PM
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While not exhaustive, here are a few refractors with focal lengths between 550 and 650mm. The list is sorted by price.
Orion ED80 StellarVue SV80ED-1 StellarVue SVR-80ED StellarVue SV-80ED Deluxe William Optics Megrez 90 Vixen ED86S Astronomy Technologies AT90EDT StellarVue SVR-90T Raptor Televue TV-85 William Optics FLT-98 DDG StellarVue SV-90TBV StellarVue SV-90TF
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Fogboundturtle
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Re: What ~600mm focal length scope for imaging
[Re: hoa101]
#5700115 - 02/25/13 03:52 PM
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Quote:
I want to point out that the title of my thread was "~600mm focal length scope..."
I really appreciate the help, but I'd like to stay on topic if possible. Thank you!
The televue scopes are definitely a consideration. I heard there was some sort of controversy about the TV-101. What was up with that?
Quote:
Quote:
Very cool-looking scope, especially at f/5. However, it's basically the same focal length as my AT65EDQ.
Quote:
how about the new Esprit 80m Triplet + Flattener ? it will be an F5 scope and the price is 999$. Should be available next month
80mm @ F5 > 65mm @ F6.5
You might want to consider than the 100ED version (550mm)?
http://ca.skywatcher.com/_english/01_products/02_detail.php?sid=419
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ghataa
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Re: What ~600mm focal length scope for imaging
[Re: Fogboundturtle]
#5700515 - 02/25/13 08:17 PM
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SV 90mm carbon fiber raptor. FL 630 mm f6.8
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MrGrytt
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Re: What ~600mm focal length scope for imaging
[Re: ghataa]
#5700618 - 02/25/13 09:30 PM
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I have no idea what your price limit might be but it almost sounds like you're describing the TEC 110FL with a focal length of 616mm @ f/5.6. There is a dedicated field flattener for it that can be purchased.
Harvey
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Skyshooter
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Re: What ~600mm focal length scope for imaging
[Re: MrGrytt]
#5700717 - 02/25/13 10:37 PM
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+1 on the Stellarvue SVR90T. It's 630mm FL at F/7. I use an inexpensive astro tech 2" ATFF flattener. Some example images here: www.flicker.com/photos/stargzr2011/
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microstar
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Re: What ~600mm focal length scope for imaging
[Re: Skyshooter]
#5700760 - 02/25/13 11:07 PM
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+1 on the Stellarvue SVR90T. It's 630mm FL at F/7. I use an inexpensive astro tech 2" ATFF flattener. Some example images here: www.flicker.com/photos/stargzr2011/
+2 I have one of these as well. Light weight with CF tube. Great optics. Nice image scale. ...Keith
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orlyandico
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Re: What ~600mm focal length scope for imaging
[Re: microstar]
#5700842 - 02/26/13 12:16 AM
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My 2c.. try to get one which already has a Feathertouch focuser. At some point you will grow tired of the stock focuser (unless it's the Tak 106) and a Feathertouch retrofit is $400.
I believe most of the SV scopes already have the Feathertouch or the new 2.5" SV rack and pinion. I don't know how good the SV R&P is. I have the AT90EDT with the 2.7" R&P and... while it is strong enough to lift a lot of camera and it doesn't slip, it does have some focus shift when reversing direction. In other words, it ain't a Feathertouch.
But seeing as I got my AT90 (used) for 2X the price of a Feathertouch, I'm not really complaining..
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hoa101
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Re: What ~600mm focal length scope for imaging
[Re: orlyandico]
#5701180 - 02/26/13 08:50 AM
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I'm still worried about the weight of the AT90EDT on my mount. My AT65 with dovetail, spacer, SSAG/finder scope, camera, etc. weighs in at slightly less than 10 lb. The AT90 is 8 lb heavier, which is getting up there if I plan to also replace the camera with CCD/filters someday.
The TMB92SS looks pretty good at f5.5 - comes with the feathertouch as well. I may hold off though on this though, since it seems I won't be satisfied with a scope that is less than ~$2k. The Raptor is nice for sure, but a touch slower than I would prefer.
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bouffetout
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Re: What ~600mm focal length scope for imaging
[Re: hoa101]
#5701239 - 02/26/13 09:27 AM
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Stellarvue SVR90T I think the carbon fiber is still on sale at $1500.
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Jason B
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Re: What ~600mm focal length scope for imaging
[Re: hoa101]
#5701242 - 02/26/13 09:28 AM
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I don't think the AT90EDT would be a bad match for your mount. Just make sure everything is balanced. I imaged with my AT111 on a AS-GT with a small guidescope until I had the finder without any issues. I think you would be ok.
Balance will be critical but I don't see a problem with the AT90/Sirius set up, IMHO, of course.
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