#21  
Old 26-02-2014, 04:59 PM
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I think a custom built Newt. gives the best bang for the buck.
Look at what Rolf Olsen has done:

http://www.iceinspace.com.au/forum/s...t=98823&page=2



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  #22  
Old 26-02-2014, 10:39 PM
clive milne
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Quote:
Originally Posted by Peter Ward View Post
Suprax as far as I can tell is a Schott borosilicate glass similar to pyrex.
Similar in its chemical composition but it is not precision annealed nor reliably as homogeneous as pyrex. Schott have even stipulated in the past in an attempt to avoid culpability (when faced with returns) that telescope optics are not a suggested use for this material.

If Orion (and ASA) are knowingly using suprax as a substrate then it is bordering on shameful. imho) (the wrong side of the border at that)

Last edited by clive milne; 27-02-2014 at 07:51 PM.
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  #23  
Old 27-02-2014, 08:52 AM
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Dear I In S'ers

Firstly you have some "telescope suppliers" involved in this thread and that is not within the rules of I In S anyway

Secondly they are "carrying a can" in their responses and also providing incorrect technical information, I suggest you contact either myself at Astronomy Alive directly if you seek true and accurate data on ASA gear - or ASA themselves

As Australian exclusive distributor for ASA I am going to be passing this thread data back to Gerald Rhemann who is the CEO of ASA as he should be aware of the incorrect and inaccurate competitor comments that are being actioned here, it is a very sad day that such tactics are being adopted (but not unusual on this website ..... unfortunately)

Clear skies

Cris Ellis
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  #24  
Old 27-02-2014, 09:54 AM
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Hi Peter

You raised the possibility of a Skywatcher scope. My Skywatcher optics seem to be seeing limited, just like the much more expensive ones, so optical quality is probably not really an issue - once you get to the seeing limit, better optics is nugatory for DSO imaging. What you will/should get with the high end scopes is much better mechanical and thermal stability, possibly the correction of primary aberrations over a wider field, plus everything should fit together and work straight out of the box. The Skywatcher could be a remarkably good scope for wide field imaging with a coma corrector and big pixels, but I would not recommend it for high res imaging with small pixels on your high end mount unless you are prepared to spend a fair bit of time fixing the weaker parts of the design (focuser, secondary mechanics etc).

Suggest that you use a fast scope with the Trius to get the best out of it. A fast Newtonian makes sense, but as you say, there is not much back focus to play with from the coma correctors in wide use. The one that does provide a fair bit is the RCC1 (91.5mm) - it is low end (so build quality might possibly be a bit variable?), but it seems to work well over a small field and might be something to consider if you needed lots of back focus and were prepared to assemble you own system (see above comments).

In any case, a guidescope might be OK with the Trius, since that camera has low enough read noise to image effectively with 2-3 minute broadband subs at f4 - you will probably be able to get a guidescope solution working well with such short subs - unguided may even be a possibility.

"what to put on an MEII" is not a bad problem to have though .

regards ray

Last edited by Shiraz; 27-02-2014 at 01:11 PM.
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  #25  
Old 27-02-2014, 10:39 AM
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Quote:
Originally Posted by Shiraz View Post
Hi Peter

Suggest that you use a fast scope with the Trius to get the best out of it. A fast Newtonian makes sense, but as you say, there is not much back focus to play with from the coma correctors in wide use. The one that does provide a fair bit is the RCC1 (91.5mm) - it is very low end (so build quality might possibly be a bit variable?), but it seems to work well over a small field and might be something to consider if you needed lots of back focus and were prepared to assemble you own system (see above comments).

regards ray
Hi Ray,
I find the RCC1 to be excellent value for money.
I have still yet to really nail the distance to the CCD chip
but I can adjust it further with a Varilock adjustment sleeve from opt.
using CCD inspector.
see here:
http://www.flickr.com/photos/2471943...in/photostream

Also this guy -Detlef Hartmann - gets some nice pics with his:

http://www.astrobin.com/users/DetlefHartmann/


cheers
Allan
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  #26  
Old 27-02-2014, 05:13 PM
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Quote:
Originally Posted by Astromelb View Post
Dear I In S'ers

Firstly you have some "telescope suppliers" involved in this thread and that is not within the rules of I In S anyway

Secondly they are "carrying a can" in their responses and also providing incorrect technical information, I suggest you contact either myself at Astronomy Alive directly if you seek true and accurate data on ASA gear - or ASA themselves

As Australian exclusive distributor for ASA I am going to be passing this thread data back to Gerald Rhemann who is the CEO of ASA as he should be aware of the incorrect and inaccurate competitor comments that are being actioned here, it is a very sad day that such tactics are being adopted (but not unusual on this website ..... unfortunately)

Clear skies

Cris Ellis
Astromelb
What!, and thats it, leave us hanging like that?. Why cant you give us the true and accurate data here, now

I, and others would sure like to know, now
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  #27  
Old 27-02-2014, 05:17 PM
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There is a used, 10" RCOS in the telescopes section of this site at the moment, with low expansion glass and all that...
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  #28  
Old 27-02-2014, 05:54 PM
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Quote:
Originally Posted by Astromelb View Post
Dear I In S'ers

Firstly you have some "telescope suppliers" involved in this thread and that is not within the rules of I In S anyway

Secondly they are "carrying a can" in their responses and also providing incorrect technical information, I suggest you contact either myself at Astronomy Alive directly if you seek true and accurate data on ASA gear - or ASA themselves

As Australian exclusive distributor for ASA I am going to be passing this thread data back to Gerald Rhemann who is the CEO of ASA as he should be aware of the incorrect and inaccurate competitor comments that are being actioned here, it is a very sad day that such tactics are being adopted (but not unusual on this website ..... unfortunately)

Clear skies

Cris Ellis
Astromelb
Chris, to whom do you refer?
Hopefully not yours truly, as I've recommended choices *that include ASA* that, as an astrophotographer I have been impressed with but have no commercial involvement.

Last edited by Peter Ward; 27-02-2014 at 07:51 PM.
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  #29  
Old 27-02-2014, 06:57 PM
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With its weight capacity, I think you would be able to fit 2 of those models they get to lean on cars for photos on it!

Plug that into your versa plate!
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  #30  
Old 27-02-2014, 07:56 PM
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Originally Posted by Astromelb View Post
he should be aware of the incorrect and inaccurate competitor comments that are being actioned here, it is a very sad day that such tactics are being adopted (but not unusual on this website ..... unfortunately)
Really?
Could you please point us to another thread that lends substance your claim.
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  #31  
Old 03-03-2014, 12:40 PM
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Really?
Could you please point us to another thread that lends substance your claim.
Ditto... Several days has passed yet by the absence of any revelation, I suspect this was just hollow commercial posturing.
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  #32  
Old 06-03-2014, 02:19 PM
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This was a surprise but I couldn't resist. It practically fell in my lap. I just picked it up in Coonabarabran yesterday. Wow!!!

Not sure I can afford to keep the TEC140 but they do look nice together!

Peter
Attached Thumbnails
Click for full-size image (TEC140 Popeye.jpg)
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Click for full-size image (TEC180-small.jpg)
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Click for full-size image (TEC180+TEC140.jpg)
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  #33  
Old 06-03-2014, 03:06 PM
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Well, this thread is officially closed!
What Would You Put on an MEII?
A TEC160 it seems !
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  #34  
Old 06-03-2014, 03:08 PM
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Wait a sec. The pic ain't that clear. Is that a 180 !!!!

Last edited by Logieberra; 06-03-2014 at 03:49 PM.
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  #35  
Old 07-03-2014, 12:15 AM
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Woohoo it's clear

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Wait a sec. The pic ain't that clear. Is that a 180 !!!!
Yeah that's what I thought but it doesn't really look big enough to me ...Pete, help us jealous onlookers out

Mike
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  #36  
Old 07-03-2014, 12:18 AM
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Woohoo it's clear

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Not sure I can afford to keep the TEC140 but they do look nice together!

Peter
Yes you can...they were made to be together, get two cameras do the Lum through the bigun and the RGB through the little tagger = imaging nirvana

Mike
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  #37  
Old 07-03-2014, 06:25 AM
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Congrats on your TEC180FL. I think you'll find as I have there is a reason why Fluorite has endured as the premium lens material all these years. Just think of all those high end Canon sports lenses with fluorite elements. I believe Canon is still using fluorite in the really long telephotos the sports photographers use.

That bit of light that other glasses scatter gets through with fluorite. Sometimes if the exposure level is long enough it will show up fine faint aspects missed in other images. Nothing major but there is a subtle pick up that it will achieve.

Greg.
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