Just spitballin' an idea

[matt]

I've been wondering lately whether it's time to move on to a new scope. You know how it is with us planetary imagers:rolleyes:

I've been quite happy with the C9.25 and I've become something of a SCT fan, even though I don't believe that visually/optically an SCT delivers quite the quality of image as, say, a newt. Photographically, it's great.

I'm going to stick with planetary imaging for a while and that means I don't mind sticking with an SCT. I'd prefer something around the 10" aperture OTA for the sake of portability.

I'm just wondering whether I'd see a marked improvement if I traded to something like a 10" Meade LX200R?

Obviously, the tiny bit of extra aperture is not going to set my world on fire, but what about the so-called 'Advanced Ritchey Cretien' optics? Would they be worth the switch?

I suspect not. I've yet to see planetary pics out of a Meade R or RCX series which would convince me the plunge would be worthwhile.

Not really thinking about other brands or types of scopes (newt, refractor etc) at this stage. Just this 9.25/10" LX200R comparo?

Just tossing the question out there to see what you guys think. :)

[Alchemy]

in a non serious manner i can hardly see that 3/4 of an inch is going to make that much difference given the 9.25 has always recieved rave reviews......you know you want that 14 inch monster......i do:D..........a definite victim of aperture fever.

[matt]

Hi Alchemy.

As I stated in my original post, the question isn't so much one of aperture and associated light gathering, but rather optical quality.

I'm not looking to 'upsize'. I'll leave that for those who are prone to such weaknesses:lol:

Cheers

[ballaratdragons]

I know nothing about SCT's, but I have read many many reviews which state that the C9.25 is probably the best Astrophotography scope in the whole SCT range.

Apparently it has something to do with the figure and other mathematical changes over other models, and it is the only model they brought out using that design.

I even remember people in here commenting on why the 9.25 is far superior for planetary work over the other SCT's.

[matt]

Yep. The 9.25 sure is a nice scope, Ken:thumbsup: I've been happy with it the last 18 months or so...

It has a slightly different (f) figure on its primary and secondary which has an impact on its capabilities.

But I am just intrigued by this new RC range from Meade.

Prob is...I just haven't seen too many planetary images captured with them.

Maybe there's a reason for that?:whistle::confuse3:

[sejanus]

A mate has a 10" lx200r and I've looked through it

I have heard grumbles that it's not a 'true' RC design - however whatever they have done, it does seem to hold sharpness/contrast at the edges better than my old C11 did.

that said, I am doubtful there'd be a big difference - maybe a small picky difference if you were searching for that last 5-10% difference? The lx200r is an expensive puppy and I think you'd see a larger increase in quality by upgrading camera gear, rather than the OTA

[matt]

Hmmm. 5-10%. I might be happy with that difference.

As far as the cost goes, I'd use the proceeds of the sale of the 9.25 to fund most of the purchase.

Hmmm. food for thought.

[sejanus]

have a look at the cloudy nights forums in the meade area, heaps of lx200r owners there

[h0ughy]

well why not get a TAK 150................

[matt]

See original post, David. Not interested in a refractor at this stage.:)

Would definitely not want to head smaller in terms of aperture, even if it is unobstructed.

And I think a TAK 150 would involve a little more coin.

[h0ughy]

OK then, what about a mewlon? ok you are after aperture

BTW I have a 10" LX200R OTA - crisp focus and collimation would be an issue - I am yet to get both together, but I am working on it. I have installed a dual speed feathertouch focuser. I cant understand why you would want to jump ship on the big C though, although the only thing I can see would be the mirror lock

[matt]

The Mewlon is another good and much more expensive option, David.

No. Am not after aperture. But as I've stated, would like to remain around the 9.25-10" mark...or thereabouts.

But I'd like to remain within the parameters of my original post, if possible.

I guess I'll just have to find someone with an LX200R and check it out for myself.

Cheers

[matt]

The power and the hype of the Meade marketing machine and as previously mentioned...a curiosity about how good the so-called Advanced RC optics really are;)

[bird]

Matt, something to bear in mind... for planetary imaging you're only using the very centre of the image, so off-axis errors like coma etc don't ever apply as you'll never see that part of the field in your camera.

You should focus your thoughts (so to speak) on a design that gives the best on-axis image, quite different from the wide-field designs like the meade RC.

Even with a simple newtonian scope with a small secondary the diffraction-limited field is several times larger than the disk of Jupiter, so as long as you're collimated properly then you'll be seeing the best image that you can get.

cheers, Bird

[ving]

hmm... in all honesty matt i think you havent gotten as much as you can out of the 9.25 and dmk. i think kyou should work on that... just my opinion of course :)

if indeed money is burning a hole in your pocket you can buy me a c8 if you want ;)

[Terry B]

What about one of the larger mak cas scopes? They are not anywhere as expensive as a refractor but will give better planetary images.

[matt]

Hi Terry.

That's definitely an option. Have been looking at the STF and Intes range for quite some time. Here's one I'm particularly interested in:

http://www.tetontelescope.com/product_info.php?cPath=53_6_17&products_id=9

The Mak-newts are also attractive.

They cut off around the 8" range as far as affordability goes, before they really jump up in terms of $$$.

Although it's a little step backward in terms of aperture, I like the idea of being able to purchase a scope with guaranteed 1/6th, 1/8th or even 1/10th wave optics.

I probably wouldn't notice the difference in aperture when imaging planets, from a brightness point of view, and the higher quality of optics would most likely compensate.

A definite possibility in the future.

[KenGee]

http://www.lazzarotti-optics.com/
nice but price not nice. Go a Mak.

[matt]

Hmm. Very nice optics, I'm sure...but I'm not a fan of such an open design.

Dew would surely be an issue. I'd also be worried about how easily crud could get on my mirrors.

You'd probably be able to encase it all in a tube of some description, but why not just buy it all in a tube from the get-go?

Anyway...what's the price????

[stringscope]

Here you go Matt:

http://www.rfroyce.com/DK%20OTAs%20Offer.htm

Cheers,

[matt]

Thanks, Ian. Very tempting.

Wouldn't mind seeing some pics of the OTA being described.

Cheers

[stringscope]

Try this:

http://www.rfroyce.com/DK%20OTAs%20observing%20rep%202.htm

[citivolus]

Might as well throw the Vixen VMC260L in the ring? 260mm f/11.5, 10Kg OTA. Granted, it has a spider which may kill it for you.

[Dennis]

Hi Matt

Whilst I haven’t experimented with a Mewlon 180 vs C9.25 shootout, I think Robert_T gave the edge to the C9.25 based on light gathering. My limited experience would tend to agree, for hi res planetary and lunar webcam imaging.

I love the M180 as a beautiful visual ‘scope, but the loss in aperture over the C9.25 is a definite handicap when trying to obtain large image scales of the planets.

Like you, I’ve had several idle moments of wishing and to that extent, my thoughts usually veered towards a planetary Newtonian. However, a 10” F6 would probably be a test even for my Tak EM200 mount.

Cheers

Dennis

[Dennis]

Having owned a Vixen VC200L (200mm F9), I understood these fine instruments were designed for flat, wide field astro photography. The resulting large central obstruction and spider vanes allegedly reduce contrast for hi-res planetary imaging.

Cheers

Dennis

[Geoff45]

The thing about RC scopes is that they are designed to take wide field star images, with no distortion of stars at the corners of the frame. This is not an issue with planetary photography, where you're only interested in a centre field image, so for planetary work an RC is a waste of money.
Geoff