SCOPE COMPARISONS-10" lx200-ACF vs 10" GSO RC vs 10" meade SN
i am looking at buying another OTA. i already have a 8" saxon mak-cass and a SW Ed-80. i have these side by side on a EQ-6 mount and it runs well although i believe it to be at the mounts weight limit. contrary to many opinions i find the mak to be a great scope. although i did have to put an electronic focuser on it and change the stsndard diagonal with a quartz dielectric. with these changes i find it visually a very good scope and i was not able to see any difference between it and a C8 celestron on a particular evening.( not saying there was no difference, just saying that i could not see it). this is for visual use and planetery imaging.
if i buy another scope i want it to be a 10" OTA.
i want a scope that is going to be-
a) better than my 8" mak for visual use
b) better than either the mak of the ed-80 for imaging.
c) cannot be heavier than my mak, which weighs in at 13kg for the OTA only.
i have been considering 3 scopes-
-the meade lx200-acf 10"
-a 10" gso ritchey cretien (supposedly arriving in the country soon)
- the meade 10" schmidt-newtonian. ( with a coma corrector)
the lx200 and the 10" GSO are about the same price new at about $3500, while the 10" SN is about $2000.
i am not sure but i believe the lx200 and the 10" SN are about the same weight at approx 12-13 kg. (cam someone confirm this?)
and i also am not sure but based on the GSO 8"RC, i expext the GSO 10" RC to weight less than 13kg( can someone confirm this?)
which scope do you think would be the better option to satisfy the requirements noted above.
thanks for taking the time to share any opinions and knowledge you may have.
for visual use & planetary imaging then the f/l can be long..i think the s/n is something like f5 ? which is short for planetary but would give very nice wide field views. of the people here with the gso RC's - i have not seen many planetary images if any..mostly used for dso..the lx with the longer f/l would be the most used planetary scope..what proportion of time will it be used between visual/planetary imaging??
for visual use & planetary imaging then the f/l can be long..i think the s/n is something like f5 ? which is short for planetary but would give very nice wide field views. of the people here with the gso RC's - i have not seen many planetary images if any..mostly used for dso..the lx with the longer f/l would be the most used planetary scope..what proportion of time will it be used between visual/planetary imaging??
thanks for the reply.
the scope would be used more for visual use than for planetery imaging.
and i would think at this stage about 60/40, DSO imaging and visual use.
The Meade ACF unit. It's meant to be quite good visually and also from an imaging point of view. The SN will have more coma, and is bigger to handle (not sure on weight). Visually I don't think it'd be as good as the ACF to be honest. The GSO RC is probably equal to the ACF from an imaging point of view (optically), but the GSO wins out on being a faster focal ratio by default. A Focal reducer for the Meade ACF will fix that though. The GSO has a larger secondary obstruction, so you'll lose contrast when using it visually from what I understand. Not what you probably want for visual observing of the planets. The meade's longer focal ratio will probably help with planetary observing as well.
Meade ACF 10" as far as I'm concerned. I'd get the OTA from Bintel and get a decent equatorial mount (if you don't have one already).
You should be aware that the improved ACF design for the Meade no longer supports the "older" x0.63 reducer.....
According to the Meade ( and other forums) there's nothing in the pipeline either.
I have the original 10" Lx200 OTA and it weighs 14.7Kg.
Last edited by Merlin66; 16-11-2009 at 10:46 PM.
Reason: weight added
You should be aware that the improved ACF design for the Meade no longer supports the "older" x0.63 reducer.....
According to the Meade ( and other forums) there's nothing in the pipeline either.
I have the original 10" Lx200 OTA and it weighs 14.7Kg.
Yes, but the Optic nextgen .7 2inch reducer( its not a corrector) was developed for Apo's and telescopes with corrected optics.
I use one with my Acf with perfect results.
I pick option #4, Celestron C9.25 Currently super cheap at a certain vendor (PM me for details, let's do everyone a favour and keep the infamous import price argument out of your thread). Yes, you would need the reducer/flattener, but it would provide a weight and price advantage over the ones you mentioned.
I doubt any of the 10" scopes you suggest will give significantly better views visually unless the Mak is optically poorer than it should be. You will get slightly brighter images though.
Just to back up the reducer comment - I use a 0.7 Optec Nexgen reducer on my 10 inch ACF as well. I would still like more reduction but haven't solved that one yet - still oversampling with the CCD (ST10) at 1750 f/l even binned at 2x2 and at 3x3 resolution goes to rubbish.
Just to back up the reducer comment - I use a 0.7 Optec Nexgen reducer on my 10 inch ACF as well. I would still like more reduction but haven't solved that one yet - still oversampling with the CCD (ST10) at 1750 f/l even binned at 2x2 and at 3x3 resolution goes to rubbish.
Mark
Wha??. The ACF 10" with a 0.7 FL and ST10 at bin 1 gives about 0.8 arsecs/pixel, right in the sweet spot, not over sampled at all??. Whats the problem with that?.
I use an AP 0.67 FR with a 12" LXR (ACF) to great effect, works very well with an ST10. In fact id say they were made for each other ;-)
Just to back up the reducer comment - I use a 0.7 Optec Nexgen reducer on my 10 inch ACF as well. I would still like more reduction but haven't solved that one yet - still oversampling with the CCD (ST10) at 1750 f/l even binned at 2x2 and at 3x3 resolution goes to rubbish.
Mark
i would be using a 450d camera. what would that mean for me? sorry if this is a noob question.
Gday Fred - best answer I have is operator incompetence. I've checked collimation etc so after what you have said (and I know that you know) it is probably just a product of imaging at this focal length
I just dont know but my images all appear as thought the stars are just too big and you can only pinch so many.
I usually use refractors (TV & Black Diamond ED120) and when I compare images the first thing I notice is what I would call bloated stars (bloated may be too strong a word) but they may just be normal sized stars for the focal length. So again it is probably operator incompetence.
Luke (Sry mate didnt know this was you) _ as discussed I dont know the answer re 450D. Best solution is to stick it on the scope out at Leyburn and try it. If you arent out there this weekend I will stick the 350D on and try.
I lean more to shorter focal length photography anyway so they (SCTs) are going to raise funds for a Tak Epsilon or similar.
Currently super cheap at a certain vendor (PM me for details, let's do everyone a favour and keep the infamous import price argument out of your thread). Yes, you would need the reducer/flattener, but it would provide a weight and price advantage over the ones you mentioned.
