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  #21  
Old 05-12-2017, 11:05 PM
bigjoe (Joe)
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Re C91/4

[QUOTE=Merlin66;1347043]+1 for the C9.25 from me.
Definitely punches beyond its weight.[/QUOTE
Ive always felt this too Ken , even though Ive just sold a great Meade 254mm SCT.. some say the 91/4 is as good as a Mewlon 210 , here and on Cloudy Nights, and for less, and NO diffraction spikes! ..Ive yet to look through one thats not fabulous.If I wasnt after an Apo I would get another.
bigjoe.
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  #22  
Old 07-12-2017, 02:47 PM
Borneogoat (Murphy)
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I'll keep my eye on the classifieds for a 9.25", but new they are quite a bit more expensive than an 8". I don't wanna go too big, otherwise cooling might deter quick spur of the moment sessions....
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  #23  
Old 07-12-2017, 03:59 PM
bigjoe (Joe)
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Quote:
Originally Posted by Borneogoat View Post
I'll keep my eye on the classifieds for a 9.25", but new they are quite a bit more expensive than an 8". I don't wanna go too big, otherwise cooling might deter quick spur of the moment sessions....
True ..once cooled with say ice pack .they cool very quickly that way..people have even used frozen veg wrapped in towel etc so they cool very rapidly ..youve got time to choose ...no need to rush ..good weather not here yet.
bigjoe.
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  #24  
Old 08-12-2017, 02:53 AM
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Quote:
Originally Posted by Merlin66 View Post
Hmmm
Based on my long experience with various Meade SCT I have to say their optics and performance were as good as any other SCT.
However, the mirror shift focus system is better on the Celestron.
My C925 and C11 has better focus mechanisms.
Just my 2c
QFT! Optics between the two are similar/superior/inferior depending on the mood in the factory at the time... (i.e. SCT optics form both Celestron and Meade have variations that are dependent on factory runs).

Quote:
Originally Posted by Borneogoat View Post
1. C8 with CGEM = $2499
2. C8 with AVX = $2499
3. C8 with HEQ5 Pro = $2699
4. LX80 with EQ5 Pro = $2099
5. LX80 with HEQ5 Pro = $2299
6. LX80 with AVX = $2299

Any advice here?
FWIW: If you go with Celestron, get an OTA that is Fastar compatible. These OTA's tend to preserve more value over time and the extra flexibility of having an OTA that can image at ~f/1.95 is "priceless"...

https://starizona.com/acb/hyperstar/whatis.aspx

OIC!

Last edited by OICURMT; 08-12-2017 at 02:55 AM. Reason: Added Hyperstar link.
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  #25  
Old 08-12-2017, 09:43 AM
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Quote:
Originally Posted by OICURMT View Post
QFT! Optics between the two are similar/superior/inferior depending on the mood in the factory at the time... (i.e. SCT optics form both Celestron and Meade have variations that are dependent on factory runs).
This is anecdotal...although if you look at CN, majority of reports of Celestron SCTs since the production was moved to China claim good to excellent optics. This implies that in recent years their production is more consistent. Of course, we're sampling a small number of users who care to post relative to the total sold...so it's all arm waving.

I can't speak from experience with Meade as I've never owned one.

Personally, I have 3 SCTs (all <10 years old) and they excel under good seeing. IMO that is the biggest challenge most owners will face, rather than any perceived luck of the draw. Most people simply don't live in locations with regular good/excellent seeing, so in practice may be better off with shorter focal length instruments. Careful collimation is also necessary to get the best views, it's not just the domain of newtonians
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  #26  
Old 08-12-2017, 06:42 PM
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You do that , as my C9.25 has never failed to impress on all objects it's an exceptional telescope easily besting a very expensive 130mm triplet APO every time and it mounts as easily as the 130 APO . ( I know this will ruffle a few feathers , but there is no substitute for aperture , as a C14 would easily beat my scope ) .

On that an AVX or HEQ5 would be perfect , I was just lucky to find a sweet CI700 mount 2nd hand here and it don't break a sweat holding the C9.25 .

On the size I have a good friend with the exact same scope but in the C8 format and the size and weight difference is really not that much , a bit longer but at a glance they are more alike than different and on deep sky that extra 1 1/4 inch is very noticable .

Planetary it is also better taking good magnifications on good nights , I regularly hit 400-500x on Mars , Saturn and Jupiter , great stuff when the atmosphere allows .

Last thing , don't worry about columation , its easy and a set of ' Bob;s Knobs ' is $20 well spent . See mine in the photo , they are the cat's whiskers for this .

Hope this helps .

Brian.
Quote:
Originally Posted by Borneogoat View Post
I'll keep my eye on the classifieds for a 9.25", but new they are quite a bit more expensive than an 8". I don't wanna go too big, otherwise cooling might deter quick spur of the moment sessions....
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  #27  
Old 09-12-2017, 09:15 AM
casstony
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I've owned a dozen SCT's over the years of various sizes. From experience and from reading interferometric testing, in my opinion the quality still varies just as it always has and there's nothing special about the C9.25; it's optical quality is no better or worse than the other sizes and they all have their pro's and con's.

The 8" is lighter and easier to cool than the 9.25. The 9.25 is easier to carry but also noticeably less bright than the 11". The 9.25 is a comfortable middle size but also not much brighter than the 8". All of them are good deals at second hand prices, though I'm partial to the Edge series because of the vents and my often dropping evening temeratures.
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  #28  
Old 09-12-2017, 10:16 AM
bigjoe (Joe)
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Quote:
Originally Posted by brian nordstrom View Post
You do that , as my C9.25 has never failed to impress on all objects it's an exceptional telescope easily besting a very expensive 130mm triplet APO every time and it mounts as easily as the 130 APO . ( I know this will ruffle a few feathers , but there is no substitute for aperture , as a C14 would easily beat my scope ) .

On that an AVX or HEQ5 would be perfect , I was just lucky to find a sweet CI700 mount 2nd hand here and it don't break a sweat holding the C9.25 .

On the size I have a good friend with the exact same scope but in the C8 format and the size and weight difference is really not that much , a bit longer but at a glance they are more alike than different and on deep sky that extra 1 1/4 inch is very noticable .

Planetary it is also better taking good magnifications on good nights , I regularly hit 400-500x on Mars , Saturn and Jupiter , great stuff when the atmosphere allows .

Last thing , don't worry about columation , its easy and a set of ' Bob;s Knobs ' is $20 well spent . See mine in the photo , they are the cat's whiskers for this .

Hope this helps .

Brian.
Hi Brian..kept these polychromatic strehl figures for C9. Kept these from an article which I no longer have..take it or leave it for what it is...NOT here to prove anything.
235mm (9.25") f/2.5 f/10 Aplanatic SCT with 35% CO:

L 486nm Strehl=0.958
L 546nm Strehl=0.9978
L 656nm Strehl=0.940
As you can see these are high figures.. the c8 for example drops off a lot away from green .
Primary is f2.5 not f2..so a Flatter field and Strehl results..its a long tube scope for its diameter..
Ed Ting says the primary has been finished as parabolic..so a variation to normal.
PS if someone whats an argument.. go ahead I will not respond .
For the record, I recently sold a meade 10 SCT AND 7 SW Mak, M8 etc.
cheers bigjoe.
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  #29  
Old 09-12-2017, 11:13 AM
casstony
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Quote:
Originally Posted by bigjoe View Post
PS if someone whats an argument.. go ahead I will not respond .
.
I guess that comment is directed at me No need for an argument, the C9 is a good scope with flatter field than a standard SCT and greater depth of focus, but production standards are the same as the other models imho: some great, most ok, some not so good.

Here's what Rod Mollise has to say: http://uncle-rods.blogspot.com.au/20...mythology.html
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  #30  
Old 09-12-2017, 11:25 AM
bigjoe (Joe)
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Quote:
Originally Posted by casstony View Post
I guess that comment is directed at me No need for an argument, the C9 is a good scope with flatter field than a standard SCT and greater depth of focus, but production standards are the same as the other models imho: some great, most ok, some not so good.

Here's what Rod Mollise has to say: http://uncle-rods.blogspot.com.au/20...mythology.html
No. Tony... just anyone in general ..your comments here are correct..its this mainly greater depth of focus that makes it perform when the seeing changes the focus in a lot of shorter F ratio Primary SCT
Cheer bigjoe.
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  #31  
Old 09-12-2017, 01:36 PM
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Quote:
Originally Posted by bigjoe View Post
No. Tony... just anyone in general ..your comments here are correct..its this mainly greater depth of focus that makes it perform when the seeing changes the focus in a lot of shorter F ratio Primary SCT
Cheer bigjoe.
My thoughts exactly and thanks for the figures , I personally vouch for them as its what my eyes tell me and that is that my C9 really performs when cool'd and collimated properly , there are detractors for anything , cars , watches , telescopes , anything as its human nature but some take it to another level .

I have a very , very good iStar 127mm f8 achro that performs great to my eyes and many others say so as well , no it ain't no Takahashi but it's mine and I love it just like my C9.25 .

Actually on that I had a sweet Takahashi M210 that was so sharp you could have sworn you were looking through a quality APO but , I hated the diffraction spikes it gave to bright objects , some don't mind but I don't like them so sold it to get my C9 , its 1/2 the price and 99% of the Tak's performance .

Brian .

ps. I don't mind a little CA ( iStar achromat ) so go figure ?

Last edited by brian nordstrom; 09-12-2017 at 01:51 PM.
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  #32  
Old 09-12-2017, 01:44 PM
bigjoe (Joe)
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Quote:
Originally Posted by brian nordstrom View Post
My thoughts exactly , there are detractors for anything , cars , watches , telescopes , anything as its human mature but some take it personally .

I have a very , very good iStar 127mm f8 achro that performs great to my eyes and many others say so as well , no it ain't no Takahashi but it's mine and I love it just like my C9.25 .

Actually on that I had a sweet Takahashi M210 that was so sharp you could have sworn you were looking through a quality APO but , I hjated the diffraction spikes it gave to bright objects , some don't mimd but I don't like them so sold it to get my C9 , its 1/2 the price and 99% of the Tak's performance .

Brian .

ps. I don't mind a little CA ( iStar achromat ) so go figure ?
Exactly Brian ..its what makes YOU HAPPY..dont have to buy a big name sometimes just for bragging rights..more of whats real at the ep..and what many others have said about the aforementioned scopes.
bigjoe.
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  #33  
Old 14-12-2017, 10:21 AM
Borneogoat (Murphy)
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This dilemma has been solved and a purchase has been made! Whose advice did I follow? Nobody's actually...

I kept stalling on the SCT idea: cooling seems to be a hassle for quick looks and $$$ add up. Stalled on the Refractor too: small aperture is limiting and big aperture is big $ again. As originally mentioned, I didn't want the Dob mount that is so frequently recommended, but fast cooling and good value is appealing. But wait a Dob is just a Newt on a special mount, so....

I bought a Bintel BT200 f/5 with HEQ5. The money left over from avoiding SCT or Refractor prices covered a TV Plossl 32mm, TV Barlow, Orion 12.5mm, and mount PSU with change to spare. A compromise, as all things are. But I got 8" of aperture that is workable for visual, and maybe AP down the line, without breaking the bank.

The only question is: How fast can Santa bring my toys?
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  #34  
Old 14-12-2017, 11:45 AM
bigjoe (Joe)
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Quote:
Originally Posted by Borneogoat View Post
This dilemma has been solved and a purchase has been made! Whose advice did I follow? Nobody's actually...

I kept stalling on the SCT idea: cooling seems to be a hassle for quick looks and $$$ add up. Stalled on the Refractor too: small aperture is limiting and big aperture is big $ again. As originally mentioned, I didn't want the Dob mount that is so frequently recommended, but fast cooling and good value is appealing. But wait a Dob is just a Newt on a special mount, so....

I bought a Bintel BT200 f/5 with HEQ5. The money left over from avoiding SCT or Refractor prices covered a TV Plossl 32mm, TV Barlow, Orion 12.5mm, and mount PSU with change to spare. A compromise, as all things are. But I got 8" of aperture that is workable for visual, and maybe AP down the line, without breaking the bank.

The only question is: How fast can Santa bring my toys?
Will make anyone happy..as its a good scope.. GSO make very capable gear. This outfit will more than get you started..
Well done and BINTEL ..the best Ive ever dealt with , matching Teleskop Express for after, and before sales service.
bigjoe.
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  #35  
Old 14-12-2017, 01:42 PM
raymo
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I hope you checked with Bintel as to whether the scope has sufficient back focus to allow the use of a camera; many Newts[outside of Skywatcher/Saxon] do not. Bit late when you come to do some imaging
further down the track, and find you can't without modifying your scope.
raymo
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  #36  
Old 14-12-2017, 06:39 PM
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Great choice , I have looked thru many GSO Newtonions and are yet to see a lemon as they have all been very good to excellent optically , mechanically good but great if you love to ' tinker '

HEQ5's ? I have owned 3 and they have all been outstanding in performance so you wont go wrong there . Tripod is the weak link but with a Newt on top it will be probably be set at its lowest setting so easily Ok for visual .

The only down side is that the 200mm is only 1000mm in focal length and if viewing planets you need high power so your awesome TV Barlow is going to get lots of use a great choice , Did Bintel suggest you getting this item ? if so another thumb's up for them .

Great choice and enjoy your Christmas present as Bintel are really on to it getting gear out in a fast and professional manner to Bintel from me as well .

Brian.

ps . you need to post photo's ,,, lots of photo's . Because without photo's it didn't happen .

Last edited by brian nordstrom; 14-12-2017 at 06:47 PM. Reason: ps.
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  #37  
Old 15-12-2017, 08:32 AM
Borneogoat (Murphy)
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Quote:
Originally Posted by raymo View Post
I hope you checked with Bintel as to whether the scope has sufficient back focus to allow the use of a camera; many Newts[outside of Skywatcher/Saxon] do not. Bit late when you come to do some imaging
further down the track, and find you can't without modifying your scope.
raymo
As a noob, I know nothing about back focus and AP. However, the OTA is recommended as a good starter OTA for AP in other IIC threads. I'll figure it out, if I go down that road later...
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  #38  
Old 15-12-2017, 08:36 AM
Borneogoat (Murphy)
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Quote:
Originally Posted by brian nordstrom View Post
Great choice , I have looked thru many GSO Newtonions and are yet to see a lemon as they have all been very good to excellent optically , mechanically good but great if you love to ' tinker '

HEQ5's ? I have owned 3 and they have all been outstanding in performance so you wont go wrong there . Tripod is the weak link but with a Newt on top it will be probably be set at its lowest setting so easily Ok for visual .

The only down side is that the 200mm is only 1000mm in focal length and if viewing planets you need high power so your awesome TV Barlow is going to get lots of use a great choice , Did Bintel suggest you getting this item ? if so another thumb's up for them .

Great choice and enjoy your Christmas present as Bintel are really on to it getting gear out in a fast and professional manner to Bintel from me as well .

Brian.

ps . you need to post photo's ,,, lots of photo's . Because without photo's it didn't happen .
I have read the BT200 is at the upper limit for the HEQ5. But we are bumping up against the budget and the next level up in mounts are getting expensive. I figured my budget was better spent on EPs that can last a long time. Hence the TV 32mm & Barlow. I suspect I can keep these even if I upgrade or add another scope in the future.
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  #39  
Old 15-12-2017, 09:03 PM
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Quote:
Originally Posted by raymo View Post
I hope you checked with Bintel as to whether the scope has sufficient back focus to allow the use of a camera; many Newts[outside of Skywatcher/Saxon] do not. Bit late when you come to do some imaging
further down the track, and find you can't without modifying your scope.
raymo
My GSO 8"F5 is fine with dslrs and astro cameras. So assume the Bintel is the same ?
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  #40  
Old 15-12-2017, 11:24 PM
glend (Glen)
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The GSO imaging newts, sold by Andrews as imaging newts, achieve camera focus easily. From memory, there is plenty of range there, however, you may need to use the supplied 35m extension to achieve focus visually with some EPs.
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