Totally Hooked - want to upgrade

[hayju01]

So i'm looking at getting a bigger scope as i want to be able to see more detail on Saturn than I can with my 90mm, I am also interested in astrophotography so i can 'prove' to me doubters (wife) that I actually did see something and the investment is worth while.

Reading various posts i've made some decisions/conclusions and I know some is subjetive and of personal preference.

8" Aperture is gonna give me maximum light for my price range

S-C is the type of scope I like as my 90mm is S-C and I have a Newt which is great but ....

Dual fork for extra stability

Celestron make for manufacture and price

This is where i'm at Celestron CPC 800 GPS (XLT)?

I am compromised by not having a EQ mount?

Will my SPC900 give me the definition/detail I crave or do indeed to upgrade?

Do i need to consider anything else?

[david o]

Just an idea...

if you're wanting shots of what you've seen, in the way of a log, have you thought about one of those real-time(ish) cameras ? Like the Mintron or similar ?

[Nexus 6]

The cpc800 will be ok with a dslr or a web cam for solar system objects, a route a lot of people are using but if you want to image dso's you would have to fit a wedge to it, a better option would be to buy a scope on an equatorial mount and then you'll be tracking the earth's movement with what ever imaging kit you use.

I will let someone who images give some better advice as I am only a visual observer but do know the scope you have mentioned.

[hayju01]

Not looking so much as a log but as a way of showing how wonderfull the universe is not just to the wife but the 4 kids too, but the Mintron sounds like an option and probably easier to get the 'approval' or may be a cooled-ccd.

@Nexus - that's what I was figuring but not having seen a DSO yet (don't think my 90mm is up to it) its hard to say. My only concern with an EQ mount and again I stress this us just personal opinion is that they seem a bit 'clunky' with a 'counterweight' etc of course this could be just my exerience with a cheap EQ mount.

[Nexus 6]

your signature shows you have a 6" Newtonian, have you not been able to see some dso's with it?

[hayju01]

The concensus seems to be that it does not have a parabolic mirror, it's of unknown manufacture (probably Chinese) and was extremely cheap at £140, so I've not even tried.

[Nexus 6]

The concensus seems to be that it does not have a parabolic mirror, it's of unknown manufacture (probably Chinese) and was extremely cheap at £140, so I've not even tried.

well its got to be worth at least one go?

going back to your question, I do think you should try and get to a local astronomy society, or maybe get together with someone who lives close to you and is also an astronomer you can then see what people are using and will then have a better idea of what new equipment you may wish to buy.

I am sure even your Konus would show some dso's too, I guess you have downloaded Stellarium which is a great help in knowing whats visable from your location, should help with tracking some of them down

just in case

Stellarium

[LMC]

It's been a while since I had an SCT, but while the 8" is a pretty good scope, you might consider buying second-hand and getting a bit more photons - the 9.25 version would be a great compromise between size and light grasp.

Unless you are planning on doing a lot of astrophotography, you will not be compromised by lack of an equatorial mount. The CPC series has pretty good go-to and tracking, and if you do decide to spend your kid's inheritence on a-p, you can always buy an equatorial wedge that effectively turns it into a fork-mounted GEM.

Enjoy!

LMC

[hayju01]

I am in contact with local Astro Club just need to find the time to get down there (not easy with 4 kids - so they're never going to get much inheritence each :-) )

I had heard some setup issues with the wedges and hear what you're saying about more photons and beings I don't really need GPS (had very good results with synscan AZ mount (until it packed up but thats another story) so I'm leaning towards the Celestron C9.25-SGT XLT GOTO - gives me the EQ and more Photon's.

thanks all

[ollypenrice]

The 8 inch SCT on a wedge and fork would be very good for planetary imaging with a fast frame camera. Webcam or, much better, DMK21 etc. In my view, and not everyone agrees with this, it would be a very bad choice for deep sky imaging.

Why I was unhappy trying deep sky with fork and wedge: hard to balance, hard to polar align, impossible, in my case, to get the autoguiding good enough, long focal length, slow focal ratio, aftermarket focuser needed... Only the Edge and ACF SCTs have flat fields and even with flattener reducer the standard ones don't manage it. I never got as crisp an image as I got with budget five inch apos, let alone with the TEC140.

I stresss, this is just my view - though I could give you a (longish!) shortlist of friends who feel as I do. When you look at a fork SCT it seems great, compact, logical, counterweight free etc. So why does hardly anyone on this forum do DS imaging with them? Because it ain't as easy as it looks!

So the real crux is your priority, planetary or deep sky imaging. Although I'm a refractor fan and, in your case, would go for a five inch apo on an EQ6, I can see that a good Newt like Mike (Yfronto's) 10 inch/EQ6 has a shedload of positives. If the priority is strongly planetary then the SCT starts to show its strongest suite. Can Damian Peach possibly be wrong? Nooo....

Olly

[hayju01]

Thanks Olly, You say you prefer Refractors and of course thats your personal preference but what in your eyes is that preference based on?

I mentioned that I am now leaning towards the Celestron C9.25-SGT XLT GOTO based on comments here and elsewhere as it seems to give me the best of both worlds (no pun intended) e.g. planetary and DSO BUT am I comprimisng something else ?

other than my vainity against c-wieghts ;-)

[Ad Astra]

Thanks Olly, You say you prefer Refractors and of course thats your personal preference but what in your eyes is that preference based on?

I mentioned that I am now leaning towards the Celestron C9.25-SGT XLT GOTO based on comments here and elsewhere as it seems to give me the best of both worlds (no pun intended) e.g. planetary and DSO BUT am I comprimisng something else ?

other than my vainity against c-wieghts ;-)

The 9.25 SGT/XLT is Celstron's new 'lightweight' german EQ mount - I haven't used one of these yet, but I've seen them in person and they look fine to me.

On the other hand... If you have the budget for the CPC model, why not go with the CGEM-800 or CGEM-9.25" ? The CGEM mount is brilliant, sturdy, accurate and will accept an autoguider. Portable and rugged, and very reliable. I have a CGEM 1100 for school and it gets loads of use (and abuse! ) and has held up beautifully.

I would consider this before anything if photography was really an item on your 'to-do' list. Check out www.celestron.com for more info.

Dan

[hayju01]

I hear you Dan but even the 8" CGEM is above my original budget and having switched to EQ mount I'd rather get the extra aperture with 9.25CGT and may push the budget by £500 to get the 11" even then I'd be spending less that the 8"CGEM.

mount v aperture........got to come down on the aperture side....hasn't it?

[Nexus 6]

I hear you Dan but even the 8" CGEM is above my original budget and having switched to EQ mount I'd rather get the extra aperture with 9.25CGT and may push the budget by £500 to get the 11" even then I'd be spending less that the 8"CGEM.

mount v aperture........got to come down on the aperture side....hasn't it?

Hi hayju. I would say for imaging most people would say the mount is THE most important factor, again I stress I am not an imager but am sure that would be the way to go. Aperture is king when that is not such a crucual issue

[kris h]

There is a celestron 8 inch SE up for sale on here for £995 the cpc

you want sells for £1500 you could buy the SE sell the mount

which could leave you with over £500 for a EQ mount

[Ad Astra]

I hear you Dan but even the 8" CGEM is above my original budget and having switched to EQ mount I'd rather get the extra aperture with 9.25CGT and may push the budget by £500 to get the 11" even then I'd be spending less that the 8"CGEM.

mount v aperture........got to come down on the aperture side....hasn't it?

If you are at all thinking of photography, I would recommend the CGEM. I cannot overestimate the importance of a rock solid mount for ease of visual and any hope of photographic success. I would seriously go for a bit less aperture in favor of going with the CGEM mount. The OTA is easy to sell/replace/upgrade - and can be done easier than upgrading the mount, which is often expensive.

I say this having just dropped 5K on a new mount last month Saved for it for years, of course. The only thing I regret is not having upped the mount much sooner. I have a CGEM 11 in the classroom (it is going out tomorrow!), and it is a beauty. Nothing like fiddly, wobbly over loaded mounts to drive you crazy with frustration and ruin your enjoyment at the eyepiece!

Like I said, you don't need to take my word for it, check out what the folks at the local club have - and ask them what they are happy or dissatisfied with in their kit. Mount troubles are a very frequent complaint.

I hope that is of some help, rather than adding to the confusion!

Cheers,

Dan

[hayju01]

I am hearing your argument, so what makes the CGEM sooo much better than the CG-5? IYHO :-)

[brantuk]

I'll bet you have seen some dos's with just naked eye. Try M42 (Orion Nebula), M45 (Pleiades), and M31 (Andormeda galaxy) for a start. Albireo is another naked eye object but you can't see it "double" till you get binocs on it

[Dob]

Praespe/Beehive cluster/M44 is another beatutiful object observable with naked eye.

Under dark sky, of course.

Also, it is amazing in bino's.

[ollypenrice]

Whatever you do, don't be undermounted if you go for a long FL SCT. The long focal length requires accurate tracking and in my case, again personal, I would not be wild about trying to go over a metre and a half on anything but a premium mount. I would not, myself, invest in a C11 on a CGEM because I would not feel certain that I would get consistently satisfactory tracking. I tend to err on the side of caution because getting good images is difficult and being at the limit of your technology is a bad place to be. Best to stay in its comfort zones. As for a C11 on a CG5, a professional product tester on here simply said, 'Unfit for purpose.' It is too light and insufficiently accurate for the FL.

Why would I personally (again let's stress that word) go for a refractor for DS imaging?

- an SCT will need a flattener-reducer (F10 is OK on special targets but hopeless in general, especially in the UK climate with limited time.)

-The SCT will need an aftermarket focuser, ideally a Moonlite to hold the reducer at the right chip distance.

-In order to benefit from its theoretical advantage in resolution the SCT will need better seeing than is usually to be had in the UK, so you take on the complications of long FL imaging without being likely to reap the benefits. Where I have been really convinced by images from 10 inch SCTs has been where an active optics device has been incorporated in the system. The very big SCTs do give great results but on ten thousand pound mounts.

-I feel the semi budget apos and certainly the top apos have sharper optics than the standard model SCTs. I don't think this is true of the ACF and Edge models but the point above remains. In the company of a professional optician I have just star tested an Altair Astro 115 apo (well under 2000 pounds) and it gave absolutely perfectly circular diffraction rings at the very edge of a 7mm Nagler EP.)

-I rarely see SCT images at a bit over a metre really out resolving refractor images at a bit less than a metre and with the shorter FL image you get a wider field.

-Very important, as an astronomy provider I really relish the 'plug and play' of refractor imaging. I hate disappointing people, hence my conservative assessments of all kit.

I know I don't have the image scale that I'd get with a 9 or 10 inch SCT but I believe in refractor resolution, viz M33 in a 5.5 inch apo.

http://ollypenrice.smugmug.com/Other/Galaxies/M33-PIX-FINAL/1016601171_mSYWy-X3.jpg

But there is no doubt that in visual observing and/or planetary imaging a C9.25 will show more than a five inch refractor. The way it shows it is very much a personal thing and you pays your money...

As ever, I would look long and hard at the MN190. Faster than the standard SCTs (4 times as fast at native) with a true flat field and really convincing optics. Not to mention a devastating track record of posted images here on SGL, which would always be my benchmark.

Olly

[hayju01]

Thanks Olly, so if I understand correctly that brings up the question of SCs v Newt to get the FL down. am i correct?

[ollypenrice]

Hi, The MN 190 is not a Newt but a Maksutov Newtonian. While being similar in F ratio to a fastish Newt it has a very flat field which is a big bonus for imaging. If you are using a DSLR with its large chip this is particularly important. Since the MN190 is so good it is very surprising that there are not more people making them. So, yes, the standard SCT drawbacks are slow F ratio, vignetting and edge distortion. The ACF Meades and Edge Celestrons have addressed the last two issues but you need to find your own salvation as regards focal reducer since they don't make their own. With some quick research you should find ones that work though. The other SCT thing is that they are highly incomplete as sold.

Have a look at the resolution seen here in M13 in an image by Steve Loughran using a Barlowed MN190 at just over f10. This is fine on a bright object assuming you can get the guiding right, as he obviously did!

http://www.steves-astro.com/images/messier/20100417_m13_2_1500.jpg

Olly

Edit, just seen your mount v aperture question. The answer, in imaging, is certainly mount. If you overload your mount by putting too much weight on it and asking too much of its tracking at monster focal lengths you would have done far better to use a shorter, lighter scope and get an incomparably better picture. In another disussion Dan voted priority as Mount, optics, camera. I voted Mount, camera, optics. No one that I can remember failed to put mount first though the camera/optics thing was kicked about interestingly.

[hayju01]

Thanks everyone for you comments and advice. Here's where I upset at least some of you

I've been in contact with FLO and had some toing and froing on what i 'really' want which is hard as i dont 'really' know.

Given my budget of £1500 and an absolute max of £2000 and that there really isn't somethign that will do planets AND DSO's really well e.g. there's always a compromise.

I have decided that I want to plump for planets to start with especially on the imaging side.

So I am currently looking at a NEQ6 mount with either a

C9.25 or 180 MAK

So that's f10 versus F15.

I'm very tempted by the MAK to give me superb planetary (and its less expensive) but my head is saying the 9.25 is the 'proper' one to go for.

I'm sure some of you will be confussed by the change in routes this thread has taken and I apologise but I can assure you that I am more confussed than you can imagine

thanks again and feel free advise on this one.

Justin

[Nexus 6]

No need for apologies mate, as long as you're happy with the kit thats all that matters

Hope you have some decent skies to test it all out when it arrives should that be your final choice

[hayju01]

Thanks Alan, just need to make my choice

I work in computers and thought chosing them was difficult!!!