Is it worth getting a 9.25" for astrophotography?

[Cody (Cody)]

I have a budget of $4k.

I've been looking at the Celestron 9.25" SCT scopes. I was interested in the one with the CG-5 mount but can splurge up to the VX mount which seems to have much better reviews. The VX mount is priced close to the CPC mount but as far as I've read I should stay away from CPC if I want to do imaging (even though the advertising has "astrophotography!" written all over it).

I was then going to get the 2" eyepiece set and whatever adapter I need to stick my Sony Nex camera onto it.

But I can't afford to go up to the CGEM series of mounts.

What I want to know is, is it even worth it? 9.25" VX + my Sony Nex camera should get me somewhere with astrophotography right? Or am I just going to come out unsatisfied?

I've read enough reviews of the 9.5" to tell me it's a great tube, some reviews on the SC-5 that dither between "acceptable" and "unacceptable" for astrophotography (to be fair, people whinge about the CGEM too!) but almost nothing on the combination with the VX mount.

I owned an 8" SkyWatcher refractor about a decade ago but it wasn't motorised so had no hope of ever doing astrophotography and was too bulky (I didn't have a car at the time, now I do!), so I sold it and have wanted to get back into astronomy ever since...

I feel a bit lost. I don't want to be buying extra equipment above whatever I get this time.

[carlstronomy (Carl)]

Cody, what scope to buy is the biggest question of anyone here on this site and no matter how hard you try you may still not get it right. You may not need to spend all the money you have set aside to get the result you want and save if for upgrades later. The scope is not always the main cost factor here are a few pointers.

1. What do you want to image? Focal length is important here. A SCT9.25 is an F10 and has a small field of view and needs are focal reducer for most photography.
2. A lower focal length (usually reflectors) will give more field of view but may give coma in your images so you will require coma a corrector.
3. Refractors are great but a good one is worth a fair amount of money
4. No mater how you go you will need a guide scope and camera setup for guiding
5. You will need a camera. (Many types and prices here a cheap Canon DSLR is a good start)
6. Your mount will be required to carry all of this weight so it needs to be good my SCT9.25 and all its gear for AP weighs around 13kg.
7. You don't buy a Ferrari to learn to drive in.

These are some small tips and many more people here will give great advice listen to all learn as much as you can and make the decision that is best for you not us.

The telescope is not always the most expensive thing when looking at AP and $4000 dollars can get chewed up quick in this game, don't spend it all on the scope, and you may not always get the best bang for your buck buying everything new. (Check out the classifieds here)

Hope this helps a little

Carl

[JB80 (Jarrod)]

I was going to say pretty much what has just been said, saved a bit of typing at least.

If cost is an issue I would look into getting a second hand NEQ6. That is the way I intend to go if I lob for the 9.25 but then again I'm not bothered by using it for deep sky stuff aside from visually.

[brian nordstrom (As avatar)]

Cody mate , my thoughts on newbies wanting to get into AP is , forget it ! .

If I was you I would grab a C9.25 on the VX mount , enjoy it for what it is that's a great visual scope , it will give awesome views of a lifetimes worth of pleasure .
If in the future you want to make yourself poor ( its not called 'the slippery slope to empty pockets' for nothing ) doing AP grab an ED80 and 2nd hand Canon DSLR from here as they come up all the time for great prices and mount these on the VX and shoot away .
But for now enjoy the night sky , save your sanity and money .

Brian.

[Tony_ (Tony)]

I started with a 9.25" on a CG-5 and an unmodded DSLR. It is quite difficult to get good images. The long focal length makes accurate tracking more difficult. The CG-5 mount is very noisy when slewing. It only took 6 months before I upgraded to a CGEM mount - which is still a relatively "cheap" mount. I then got a guide scope etc - which introduced me to the problem of differential flexure.

Don't expect to match the images posted on this site - they are mostly taken by expensive top of the range equipment by people who dedicate a LOT of time to their images. After 3 years I still don't come even close. With more effort (and expense) I could get better images - but there just aren't enough clear nights here to justify it.

On the other hand, my noisy, fuzzy, slightly out of shape images still give me a lot of satisfaction. As long as you don't have high expectations to start with - most combinations can be fun. An ED80 to start with is a good idea - you will get sharper images and tracking is less of a problem. If you go down the path of obsession with this hobby it can be very expensive.

Regards,
Tony.

[5ash (Philip)]

Hi Cody,
I have used a 9.25" on an NEQ6 for a number of years using a f6.3 and f3.3 focal reducer for various types of astrophotography using G-star and Samsung ccd cameras, Sony nex5 and canon 60d with good results. The nex5 is a nice lightweight camera with low noise , so it would be a good combination.However with the long focal lengths involved you really need to consider autoguiding.
Philip

[JZ (Ross)]

Hi Cody,

I started in AP about a year ago when I bought a Vixen 8" VC200L which is a dedicated AP scope. This is a wonderful scope but is not for everyone.

The first thing I learned was that the mount is far more important than the scope and needs to be the best you can afford. If you don't have a mount that is up to the job you will not get good photos.

Having said that obviously the scope plays a big part too but you can good pictures from a second hand digital SLR camera and a 50mm lens or a fancy CCD camera and a $15,000 scope! It depends on the objects you want to shoot. The critical thing is to keep the camera steady during the exposures, and the longer your focal length is the more critical it is. And long focal length F10 scopes need long exposures.

I went to a star party and found many of the people were using EQ6 mounts and smaller scope like the ED80 or 8" Newtonian. The photos these people were producing were very good.

As I wanted to computer control my gear I decided to get a second hand EQ6 and a 65mm refractor along with a laptop and the free EQmod software. I spent several months learning to use this gear and then bought an auto guider setup which allowed me to get longer exposures.
Most of the learning was how to polar align the mount as this is also critical.

My next step was to mount the VC200L side by side with the 65mm refractor, which I now use with the guide camera, and to mount a second DSLR with an 85mm lens on the system as a wide field camera.

This is where I am now and I am very happy with the setup. I have the 8" with a field of about half a degree, the 65mm with a field of about 3 degrees and the second DSLR which I can use with a range of lenses for wide field. I also use a small tracker with a DSLR and wide field lens for time lapses and get a lot of enjoyment from all of the results!

Cheers,
Ross...

[Cody (Cody)]

I've found a much cheaper source importing scopes even after freight and tax and duty. So my current inclination is towards a Celestron 9.25 or Edge on a CGEM mount.

Funnily enough that has complicated things even further, because there turns out to be surprisingly few people using the Edge scopes to compare with, and no Celestron approved focal reducer except for the non-Edge model.

I'm going to try to wait, take a deep breath, read some magazines and get to some local meet ups when they happen next and take a look through their equipment. I even looked into the option of a beautiful 10" reflector on one of those EQ6 mounts, I just feel like I went halfway down that path before and would not take it out as much due to bulk alone as if I went the SCT route.

[JZ (Ross)]

Hi Cody,

What F ratio 10" were you looking at?

The 8" F4 or F5 are fairly small and light and make great imaging scopes.

Cheers,
Ross...

[Amaranthus (Barry)]

The C9.25 is a native f/10 - it's a SCT remember Ross (down to f/6.3 with a FR).

[Nortilus (Josh)]

Dont get the Celestron Cgem mount...I would say get the Skywatcher NEQ6 as they have so much online support in the way of forums and software and even mechanical upgrades...With this mount you can go along way. Also start with a short focal length. I have an 8" meade sct and at f/10 i can be hard sometimes as a beginner...trust me on that as I'm stuggling...my advice is start small and see if AP is what you want to do...otherwise you will invest alot of money and have gear sitting around doing nothing.(I'm approaching the $7000 mark and still need to spend more to get where I want to be.)

[Camelopardalis (Dunk)]

Have a look at the SW AZ-EQ6 mount...it's a couple of hundred more than the standard EQ6 but gets belt drives and dual encoders as standard and has the alt-az mode thrown in. I have the NEQ6 and would change in a minute given half a chance, as I much prefer alt-az for visual with an SCT. The mount is the most important thing here and the AZ-EQ6 should take a lot of scope for visual, and some decent kit for AP.

I have the Edge 8" scope (but not the 9.25) and it gives a very flat field and is coma free to the edge. I've just started imaging with mine and bought the reducer for that purpose. It gives a decent image circle for an APS-C sized chip, but full frame you will see vignetting...you need the Edge 9.25 for the larger circle, as you noticed there's no reducer for that model...yet.

For large targets, you would want a short focal length refractor. I've been having a lot of fun with mine recently. Regardless, you will want a guider...I've been only getting short subs without one.

But definitely think about getting a decent mount and then check out the classifieds for scopes to experiment with and get a feel for what you like to image

[casstony]

Starting with short focal lengths makes it easier to learn imaging. My Astro Shop has the ED80 OTA on special atm for $500; you could put that on a AZ-EQ6 now and add a larger scope later on if you stay interested in imaging.

The AZ-EQ6 can be used for imaging with a bigger scope or in alt/az mode for visual if you decide imaging isn't for you, so the mount will be very useful regardless of how your interests develop.

[Amaranthus (Barry)]

I mount either a C8 + ED80T CF, or a SW120 + ED80T CF to my AZ-EQ6, and it holds it all beautifully, with plenty of margin (I run at about 50% the mount's rated capacity). Driven by EQMOD, it's a dream.

[g__day (Matthew)]

Having started astro-imaging on a C9.25 on a CG5 mount I would say it is do-able but not fun. The scope is very nice - but the mount is under whelming when it comes to its build, pointing and tracking precision and smart's of its hand controller.

If you have a DSLR you can do decent astro imaging with that to start with - once you figure a few things out.

A SCT at F/10 is a slow scope with a small field of view - think an object the size of full moon will be your maximum field of view - say 30 arc minutes - which is a fair but.

There are two 9.25 SCTs for sale in the classifieds at present - a carbon fibre version for $1500 - including a much needed high precision focuser (carbon fibre retains focus as the temperature drops beautifully) or a Edge HD one for $2100 - which will give coma free views. My personal preference would be the CF version given the subjects I like to image are near the centre of my images and coma is minimal until you get out to 80% away from the centre of the image.

For a 2K budget you could get a mid range 4" - 4.5" APO - so it depends what you want to image, a much faster APO will get a very nice scope that is a lot simpler to use and should be far more be trouble free.

A large SCT can also suffer mirror shift or flop - so you'll need a Off Axis Guider and a second guide camera if you want to take longer duration shots. That could set you back say $600 for the OAG and a simple guide camera.

I would skip the CG5 and either get a EQ6 for around $2K or consider the far more capable G11 for $3.5K that is currently for sale.

The 9.25 CF SCT + focuser + G11 + OAG + Guide camera runs to $6K but would be a killer set up that could really last well. Your budget I would say doesn't hit a natural price point sweet spot for a larger SCT. I can't stress enough with a large SCT get a very decent mount. A 3.5" = 4.5" APO will be simpler to learn with.