Advice re: SkyWatcher & Saxon (are they the same?) cassegrain telescopes

[Shooting_Star]

Hi all,

I'm new on this forum and am happy to find an Australian one! EDIT: Not for any other reason than most of the information/books I look at about constellations etc are based on Northern Hemisphere viewing ;-)

I was hoping to get some advice on cassegrain telescopes, which I'm given to understand are the best kind for astrophotography. I have been playing around with my Canon EOS 1100D and taken some decent shots of the moon and star fields, but am now keen on finding a telescope that will provide further enjoyment in the hobby.

For my budget, I was looking at both of these:
Saxon SAX-90125EQ Maksutov Cassegrain (http://www.opticscentral.com.au/saxon-90mm-maksutov-cassegrain-telescope.html#.UhLIz9L7Bz4)

SkyWatcher MAK90EQ1 (http://www.opticscentral.com.au/skywatcher-90mm-eq-maksutov-cassegrain-telescope.html#.UhLJBdL7Bz4)

What is the difference between the brands? And, if any, which one is better?

Would this focal length and other specs be suitable for some deep-sky and plentary imaging? Or would is be better to go for the 102mm in either brand?

The more expensive ones are a little outside my budget, but I guess if they're significantly better ...

This isn't technically my first scope - I used to have a Skywatcher Dobsonian, as recommended for a "first scope", but I found it cumbersome and I couldn't "put it away". Since then I've looked at the Celestron NexStar series which I love, but I've read that the mount on those is not good for astrophotography (not to mention they are expensive).

I'd really appreciate any thoughts on the two telescopes I linked to above, or suggestions as to better alternatives around that price range.

Looking forward to hearing from you and sharing some of my photos soon!

Thanks,

Romina.

[bigjoe]

Hi Romina.

I would think those scopes are basically the same. There long focal length would be

useless for most deepsky work. Unless you buy a cheap reducer, maybe the GSO

one. That could work. These scopes also only have 90mm aperture so would be dim

even for visual use. I have an 4 and 5" Mak I'm thinking of selling (if interested).

They have brighter images.

If it were myself though, I would save up for an Heq5 and 6" sct or Gso Rc or 80ed and reducer. Also your camera may not be great at imaging the planets but good on deepsky.

Cheers bigjoe.:thumbsup:

[dannat]

Both are probably only suitable for moon photography, the long focal length isn't really suited to deep sky objects

You may be better getting a vixen polarie, ioptron skytracker to get some pics with your camera & camera lens, then upgrade to a equatorial mount if you want to continue on the hobby

[mental4astro]

Hi Romina,

:welcome: to IIS, :)

The two scopes you mention are just visual instruments, particularly with the mounts they come with. You would find trying to do any kind of photography with either one most frustrating. Firstly, these mounts are just not strong enough to take the added weight of a camera, & the clock drive that are made for these mounts both neither strong enough nor accurate enough for what you want.

For the $400 budget your links suggest, and just expansive wide field shots are not what you want, there is a clever alternative that will allow you to both learn many of the image processing techniques that more involved photography requires, you'll also be able to save more money whilst you cut your teeth with of all things a webcam & your dob. A webcam is a very good and inexpensive way to get started, & even get exceptional results.

Though limited to the Moon & planets, there are two ways that a webcam can be used: the easiest is just to take a single frame picture - good, but the image quality can be very hit & miss due to the influence of thermal currents in the atmosphere. The second is making a film clip of the target. This is actually nothing more than a long series of single shots, but then you use software to stack these individual frames to produce a very high quality final image, just as is done with using more elaborate gear. Exactly the same. Tracking with a dob isn't necessary as the software is powerful enough to align the individual frames!

There are many lunar & planetary imagers here in IIS that use this technique with their dobs to produce exquisite images. It isn't a Mickey Mouse technique. It works, & what you learn with this form, as you save your $, will help you immeasurably should you want to go down the deep sky route.

There are several articles in the Projects & Articles heading that deal with webcam photography. I suggest you go through these if only to familiarise yourself with the technique, & see that it is a very productive starting point, & you won't need to burn a whole lot of cash on telescopes that aren't upto the task.

I've made my own little webcam mod for my dob too following the instructions in one of these articles. It works. The webcam can also be used as a live video feed to a screen to show a large audience.

If you rather not make the changes to a webcam yourself, there are some for sale in the classifieds.

Webcams can also be used for DSOs, but this does require better quality scopes & mounts than those noted in your links.

Taking good deep sky images is not a cheap exercise. But there are some excellent alternatives that can be starting steps, or even prove sufficient for your needs.

Mental.

[Shooting_Star]

Thanks, all, for your responses. I really appreciate you taking the time to offer some advice :)

Sorry, haven't figured out how to quote from the quick reply window :confused2:, so hopefully you see this:

Mental - thanks for the warm welcome :) that sounds like an interesting technique. If I still had my Dobsonian, I would definitely have tried that, but unfortunately I sold it not too long after I first bought it. It just took up too much space in my tiny bedroom! Pity, as it seems like it woulda have been a reasonably cheap in comparison way to get started.

Dannat - I had a look at the Polarie and it does seem like a simple alternative to get some better landscape photos. My star fields are limited to about 8-10 secs max before starting to trail noticeably, so unless I'm in the country, you can't see too many stars ... Though the moon looks much clearer than I expected of my DSLR. Have you used something like this before? What sort of tripod would you need for this to work well? At the moment I have a very flimsy tripod as I wasn't sure what sort I'd need when I bought the camera, and since I was thinking I'd get a scope eventually to piggyback the camera on ...

Bigjoe - thanks for the honest opinion. It seems like I might just need to be a little patient and save up a bit more before getting something ...

Ideally, I want a scope that is good both for viewing and for AP, but is compact and reasonably simple to use. Maybe that's too tall an order for now! Might have to do some more reading before taking the plunge ...

[mental4astro]

Another option is to get out to a star party, either an informal one or one organised by an astro club. A couple of regular informal gatherings happen at the Pony Club up at Mangrove Mountain, north of Sydney, and the other is at Katoomba Airfield in the Blue Mountains. There people set up both visual and photo rigs, and it would be a good opportunity to see the type of gear that's being used and the sorts of results that are had. Nothing beats seeing the Real McCoy first so you can make as best an informed decision. Notices for both of these gatherings are in the "Star Parties" forum. These are usually slated for the new Moon weekends. Others around Sydney are occasionally listed there too.

For astro clubs, look under the "Our Community" heading in the left margin.

At the Airfield this month, there were scopes, still cameras and a Polarie set up for imaging. Some folks take their imaging very seriously and have the gear to match. Others are just happy to do simple 15sec exposures of a wide field. It is very diverse the range. The visual boys and girls are also very diverse, some with small refractors all the way up to 17.5" dobs. From push-pull to some amazing go-to set ups. Pick your poison really, :lol:

The main thing you'll see is the gear in operation. What's involved, the scopes and what they can and can't do, the power requirements, the mounts, everything. AND you can ask questions - stroke an ego a little and they'll tell you everything, :D . This will prove most invaluable as you'll be able to avoid some costly errors.

In the mean time, you might want to reconsider getting another dob from the classifieds. They aren't too expensive, you'll be able to get good results with a webcam, and when the time comes to upgrade, you can sell-on the dob and you won't be too far out of pocket as compared to buying new.

Mental.

[Shooting_Star]

Thanks Mental, I'll have a look into that. Thanks for the tips :)