Forget about the Meade Series 5000 Plossl and the Meade 126 Barlow, neither are all that good and would be a step backward IMO. Stuck with good quality eyepieces and accessories if you can.
I'll make the council wait! Best I can do. If they want their money spent wisely they will have to wait for the results of my research.
Dumb part is they want the quote next week but the observatory won't be built for probably 6 months by the time the land is set up, mud bricks made, dome constucted, etc, etc.
Do you have a Gaming Commission in Vic? We got a state government grant from the gaming commission to get the Mapleton Observatory off the ground. Might be worth a look at seeing if there is something similar down your way.
One of the other guys involved is going to apply for a grant under the Nat-Geo science grant scheme. $5000 per successful applicant. That would top off the council grant nicely.
Attached is the current web listed prices from Andrews Communications for 8",9.25 & 11" Celestrons on a CG-5 GT mount.
<TABLE class=content cellSpacing=0 cellPadding=2 border=1><TBODY><TR class=tbl_title><TD colSpan=3>Celestron Advanced Series Computerised Go-To Schmidt-Cassagrain Telescopes </TD></TR><TR class=tbl_hdr><TD class=desc>Model</TD><TD class=price>Price $(AUD)</TD></TR><TR class=tbl_text><TD class=desc>C8-SGT 8" (200mm x 2000mm) Go-To Schmidt-Cassegrain with Starbright XLT UHT coatings </TD><TD class=price>$2499.00</TD></TR><TR class=tbl_text><TD class=desc>C9.25-SGT 9.25" (235mm x 2350mm) Go-To Schmidt-Cassegrain with Starbright XLT UHT coatings </TD><TD class=price>$3499.00</TD></TR><TR class=tbl_text><TD class=desc>C11-SGT 11" (279mm x 2790mm) Go-To Schmidt-Cassegrain with Starbright XLT UHT coatings </TD><TD class=price>$4299.00</TD></TR></TBODY></TABLE>
The mount may not meet your need/expectations for astro-photography but has had good reviews as a go to visual mount. Some reviews have also had concerns about its handling of the weight of the 11" OTA.
if you have forks, like a dob, you have alt / az motion. Like your dob, we could drive the two motions, left/right & up/down with motors to keep up with the earth's rotation.
If however you can tip the base up like i am trying to do in this photo to coincide with the latitiude you are at and also point it exactly at the southern celestrial pole, then you have an equatorial mount.
You now only really need to drive in one direction to keep up with with the earth spinning the RA (Right ascension).
If you have forks (including dobs), then two directions are needed to be controlled, but you don't have to worry about aligning anything. If you can get a equatorial setup, then only 1, BUT, you have to be so good in aligning it with the southern celestial pole
The next issue is field rotation.
Lets say you dob has been motorized and is now merrily tracking say the crab nebula. Over a length of time, the centre of the object is still in the centre, but the further out from the centre, the stars and stuff are rotating as well. This is field rotation!
This is the problem with forks & dobs when imaging. EQ mounts will not suffer this.
So, if you have forks, then to get long exposures happening, then you need to add a wedge. The wedge tilts the forks to an angle to compensate for you latitude.
I always think of it like this, that if i was at the south pole (90 degrees south), freezing my goolies off, then i put my dob down and then as the earth turns, i just swing my base around in the horizontal movment to follow the earths rotation! 0 degress tilting is needed to be polar aligned!
As i move my scope to tassie, ie 43% latitude, i need to tilt my base 47 degrees (90-43) and point it dead south to get it equatorially aligned.
At the equator, it would need to tilt the whole thing 90 degrees and pointed south or north to get the eq aligned.
Definately a structural issue, not "flick of the switch"
For visual, if you are tracking then we would not even notice the field rotation on a fork mount, but if you were capturing an image over 2 hours, then it would be very noticeable!
You can buy field derotators that try and stop this, ie try and rotate your camera, and software technology called "drizzle" tries to adjust the image.
I'm just a humble dobber. That's all way over my head Paul, sorry mate.
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