Upgrade Time - Has Anyone Used These?

[Blake (B)]

Hi everyone!

So, I was tossing up whether or not to upgrade a long time ago, and now that I've got a 4x4 and can access some nice remote dark campsites, I think it's finally time.

Like most newbs looking to upgrade, I've done a tonne of research and read enough reviews and opinions to the point that my brain begs for mercy, but before I spend any money, I wanted to seek some opinions from some folks with more experience than me. At the moment, I'm using 50mm binoculars and an alt-azimuth el cheapo refractor.

So my budget firstly, under $5000.

Mount wise, I'm thinking the SkyWatcher AZ-EQ6 GT Mount for it's sturdiness, fairy reasonable price, and the fact that it can be used as an EQ mount or AZ (which will be beneficial for visual work and eyepiece positioning).

Scope wise, I think I've decided on the catadioptric type of scope, and hopefully someone here can offer me some advice/opinions on the choices. They are:

- SkyWatcher - 190mm MAK NEWTONIAN OTA
OR
- SkyWatcher Black Diamond 180mm MAK OTA

A Maksutov, from what I've read, offers a very flat field, eliminating the need for a coma corrector, with good contrast, pin point stars without diffraction spikes, and close to refractor performance suitable for astrophotography work and visual work. There are some concerns I have with these two scopes however.

Firstly the Mak-Newt, I've seem astrophotography from these types of telescopes, and often stars seem to have 2 diffraction spikes, the cause of which I believe is inward travel of the focuser to the point where it protrudes inside the tube. Does anyone know if the SkyWatcher Mak-Newt suffers from this? I would also like to use binoviewers at some stage, and from what I've read there are some issues with Mak-Newts focuser travel and binoviewers. I think they may be used but you also need some sort of 2x magnifying parfocal lense?

With the Mak-Cass, the major concern is the focal length. F/15 seems very slow, which might be good for planetary and smaller objects, but can wider field objects like the orion nebula or andromeda galaxy fit in the fov of this scope?

If anyone can offer and advice or opinions, it would be much appreciated. If you think I should find a different scope, let me know.

Thanks!

[clive milne]

Blake,
Unless you are doing CCD imaging forget about the equatorial mount.
Your best bang for your buck would be a 12" to 16" Alt Az (dob)
Get an argo-navis to find stuff (a decent star atlas is a good way to learn the sky though)
Get one or two good eyepieces, (for an F/5) one of them should be somewhere between 12mm - 17mm focal length. My choice would be an Ethos, but a nagler type 4 or Pentax would be better if you wear glasses.
Also, a NBP filter from DGM optics is pretty much essential.

Before you spend any money though, go out to an astronomy club dark sky night and have a look through different telescopes to compare.

~c

[Blake (B)]

Clive,

Thanks for the response!

The thing is, ultimately, I want to get in to imaging. I've considered the dob option as you recommended, and whilst it would be great for visual work on the side, and at a very reasonable price, I feel like the $700ish (plus the cost of the argo) I'd spend on the dob could go towards other gear if that makes sense? I may still even buy a dob at some stage but for now im thinking about transportability and spending my money on a set up that doesn't limit me too much, and allows me to do some good visual stuff, but do great for astrophotography.

I've also considered starting with another refractor like the Orion ED80 CF which would also be a great scope, but again the money I'd spend on that could go towards a ccd camera in the future, and regardless of starting photography with a simple refractor or a reflector, the extra things like collimation I'll need to learn eventually anyway.

I agree it would be best to go to a star party or something to see some scopes in action, but I can't seem to find any events or clubs in the NSW Hunter Valley area. You wouldn't happen to know of any would you?

Thanks again!

[Lee]

Originally Posted by Blake

.....
With the Mak-Cass, the major concern is the focal length. F/15 seems very slow, which might be good for planetary and smaller objects, but can wider field objects like the orion nebula or andromeda galaxy fit in the fov of this scope? ....

A full size DSLR sensor at the focal length of these bad boys will give you a field of about 45'x30'....
Andromeda - no way....
Orion - will squeeze in the central areas....

These scopes will just frustrate you in imaging as a beginner (or even an old hand!) - think more along the lines of a refractor or maybe even a fast newtonian - a refractor like an ED80 is a great imaging scope, and you'll always find a use for it even once you've moved on to a C14 or such....

[Camelopardalis (Dunk)]

ED80 would make a great finder scope for a C14

[Steffen]

For visual those Maks will be great, but for imaging you'll likely want a focal reducer.

Cheers
Steffen.

[AstroJunk (Jonathan)]

Great mount choice.

Add an 8" F4 newt eg: http://www.bintel.com.au/Telescopes/...oductview.aspx

to give sweet visual use and and easy entry into astro photography with a DSLR, then add on the 50mm orion autoguider.

Add a dark sky and enjoy...

[Lee]

Originally Posted by AstroJunk

Great mount choice.

Add an 8" F4 newt eg: http://www.bintel.com.au/Telescopes/...oductview.aspx

to give sweet visual use and and easy entry into astro photography with a DSLR, then add on the 50mm orion autoguider.

Add a dark sky and enjoy...

I'd agree with that newt... I use one now - a nice scope, the focuser is 'OK', but the scope is greatly improved with a moonlite.... Can't vouch for it visually though....

[Blake (B)]

Originally Posted by Lee

A full size DSLR sensor at the focal length of these bad boys will give you a field of about 45'x30'....
Andromeda - no way....
Orion - will squeeze in the central areas....

These scopes will just frustrate you in imaging as a beginner (or even an old hand!) - think more along the lines of a refractor or maybe even a fast newtonian - a refractor like an ED80 is a great imaging scope, and you'll always find a use for it even once you've moved on to a C14 or such....

Originally Posted by Lee

I'd agree with that newt... I use one now - a nice scope, the focuser is 'OK', but the scope is greatly improved with a moonlite.... Can't vouch for it visually though....

I thought that might be the case lol. It would be good for planets though I'd imagine haha and visual as Steffen mentioned. You really can't get away with one instrument to cover dso's and planets can you.

When you say you can't vouch for the f/4 newt visually, is that because you don't think it's very good visually? Or you just don't/haven't ever used it visually?

Originally Posted by Steffen

For visual those Maks will be great, but for imaging you'll likely want a focal reducer.

Cheers
Steffen.

What sort of focal reducer would you recommend? How much faster could you make the scope? And would a focal reducer introduce any other issues?

Originally Posted by Camelopardalis

ED80 would make a great finder scope for a C14

I agree with you there haha. I can see it being a good investment long term. I mean you cant really go wrong with an apo refractor as far as I know. I think it's just the fact that it's not much of an aperture improvement over my 60mm cheapo refractor that's making me hesitant. After all there's so much emphasis put on the fact that aperture is king, but yet you still read opinions from people who say they've had better views through an 80mm apo refractor than through an 8 inch sct or something similar. Has anyone else experienced this also?

Originally Posted by AstroJunk

Great mount choice.

Add an 8" F4 newt eg: http://www.bintel.com.au/Telescopes/...oductview.aspx

to give sweet visual use and and easy entry into astro photography with a DSLR, then add on the 50mm orion autoguider.

Add a dark sky and enjoy...

I've heard a lot of good things about the SkyWatcher mounts and how important the mount is, so I figure I'd go with well liked mount with a lot of fans.

Have you tried the f/4 newt before? I did read something a while back about them when they caught my attention, but for some reason, I can't quite remember what the reason was, but I was a bit discouraged from the scopes. Might have just been someones personal opinion. Perhaps the fact that the fast focal ratio meant that it wasn't great for planets.

I'm guessing I will need some sort of serious coma correction for such a fast scope? And I imagine collimation may be difficult as well?

Also, I'm not the biggest fan of massive diffraction spikes in images, which is part of the reason the maks were attractive, but I've come across the curved and sine wave shaped spider vanes that are supposed to eliminate diffraction spikes. I can't find any real images comparing the different shape vanes though. Has anyone tried the curved vanes?


Thanks for all the replies!

[Lee]

Originally Posted by Blake

When you say you can't vouch for the f/4 newt visually, is that because you don't think it's very good visually? Or you just don't/haven't ever used it visually?

.....

I'm guessing I will need some sort of serious coma correction for such a fast scope? And I imagine collimation may be difficult as well?

I've never put an eyepiece in it!
You definitely will need a coma corrector, not sure if collimation is more difficult - apparently you need to keep a closer eye on it though.... Mine doesn't seem to shift much, but is in an obs and not moved much....

[Blake (B)]

Originally Posted by Lee

I've never put an eyepiece in it!
You definitely will need a coma corrector, not sure if collimation is more difficult - apparently you need to keep a closer eye on it though.... Mine doesn't seem to shift much, but is in an obs and not moved much....

Haha fair enough!

Ahh okay. Well I'd say I'd be imaging every weekend, and I'm only going to move it in and out of my shed 95% of the time, so once I collimate it I should only need to check up on it before use which for imaging is something that should probably be done anyway. You don't get any mirror flop or anything? You're happy with it as far as imaging goes? Have you got any favourite piccys on the forums here I can look at?

[Camelopardalis (Dunk)]

I can't speak for everyone, but I've always had great views through my 8" SCT... 80mm v 200m, the 200mm should win every time.

Where the ED80 comes into its own is imaging. With imaging, focal length (or lack of) counts, not aperture.

My suggestion was based on a 2-scope approach. You would need/want a larger aperture scope for visual observation.

[clive milne]

Blake, if you want to do imaging, spend the lion's share of your cash on the mount. A 10" GSO newtonian on an EQ8 is conceivably within your budget. If you are lucky you might be able to pick up a Losmandy Titan for a similar amount of coin second hand (rare, but preferable).

To appreciate what can be done with such an instrument, go here:
http://www.iceinspace.com.au/forum/s...d.php?t=107812

[Lee]

Originally Posted by Blake

Haha fair enough!

Ahh okay. Well I'd say I'd be imaging every weekend, and I'm only going to move it in and out of my shed 95% of the time, so once I collimate it I should only need to check up on it before use which for imaging is something that should probably be done anyway. You don't get any mirror flop or anything? You're happy with it as far as imaging goes? Have you got any favourite piccys on the forums here I can look at?

I should check my collimation more.... I haven't noticed mirror flop, doesn't mean it isn't happening, 800mm F/L is forgiving though...

First light image here - http://www.iceinspace.com.au/forum/s...d.php?t=105340

Another - http://www.iceinspace.com.au/forum/s...d.php?t=105831

[bigjoe (JOSEPH)]

Blake,ive had Gso f/4 10" imaging newt and its no good on planets visualy. Great on dsos like globulars and open clusters.The mak even 5"one would absolutely kill it on planets. Even with just gso plossels.cmheers

[Steffen]

Originally Posted by Blake

What sort of focal reducer would you recommend? How much faster could you make the scope? And would a focal reducer introduce any other issues?

I'm afraid I can't really give any advice as to specific parts. I know Intes-Micro make 0.55x and 0.8x focal reducers for their Maks. You need to find out whether Skywatcher have something similar for theirs, or which generic ones would be suitable.

Cheers
Steffen.

[AstroJunk (Jonathan)]

Originally Posted by Blake

Have you tried the f/4 newt before? I did read something a while back about them when they caught my attention, but for some reason, I can't quite remember what the reason was, but I was a bit discouraged from the scopes. Might have just been someones personal opinion. Perhaps the fact that the fast focal ratio meant that it wasn't great for planets.

I'm guessing I will need some sort of serious coma correction for such a fast scope? And I imagine collimation may be difficult as well?

Also, I'm not the biggest fan of massive diffraction spikes in images, which is part of the reason the maks were attractive, but I've come across the curved and sine wave shaped spider vanes that are supposed to eliminate diffraction spikes. I can't find any real images comparing the different shape vanes though. Has anyone tried the curved vanes?

There is no such thing as the right scope - only the least wrong one under your current circumstances. If you find you have the astrophotography bug, then you will start hemorrhaging money like a Knight in a Monty Python film and you will find that you only look at the edges of images for defects, not the at the subjects themselves!

Spider vanes will be the very least of your worries as soon as you notice that the top left corner of your image has distortion due to an off square focusser and you can no longer live without spending three grand on a bellows...

Run now before it's too late

[bigjoe (JOSEPH)]

I second astrojunks opinion. Unless your imaging planets and bright dsos run for your
life.Youll be at the soup kitchen in no time!

[Blake (B)]

Originally Posted by AstroJunk

There is no such thing as the right scope - only the least wrong one under your current circumstances. If you find you have the astrophotography bug, then you will start hemorrhaging money like a Knight in a Monty Python film and you will find that you only look at the edges of images for defects, not the at the subjects themselves!

Spider vanes will be the very least of your worries as soon as you notice that the top left corner of your image has distortion due to an off square focusser and you can no longer live without spending three grand on a bellows...

Run now before it's too late

Originally Posted by bigjoe

I second astrojunks opinion. Unless your imaging planets and bright dsos run for your
life.Youll be at the soup kitchen in no time!

Hahahaha! You're supposed to be encouraging me to spend the money! I can't do it myself!

Originally Posted by clive milne

Blake, if you want to do imaging, spend the lion's share of your cash on the mount. A 10" GSO newtonian on an EQ8 is conceivably within your budget. If you are lucky you might be able to pick up a Losmandy Titan for a similar amount of coin second hand (rare, but preferable).

To appreciate what can be done with such an instrument, go here:
http://www.iceinspace.com.au/forum/s...d.php?t=107812

Wow. I have to say, I'm pretty impressed!! An EQ8 would be unreal, heavy, but unreal. I can see this getting expensive already haha

Originally Posted by Lee

I should check my collimation more.... I haven't noticed mirror flop, doesn't mean it isn't happening, 800mm F/L is forgiving though...

First light image here - http://www.iceinspace.com.au/forum/s...d.php?t=105340

Another - http://www.iceinspace.com.au/forum/s...d.php?t=105831

Awesome pictures! Black and white is unique. Different from the usual colour filter approach, but I like it. Gives a sense of realism. The stars look good too. I'm no expert, but it doesn't look to have much/any coma or field curvature anywhere.

Perhaps a 2 scope approach is the way to go. Maybe a Mak-Cass with an 80mm apo refractor on an AZ-EQ6 GT mount, piggybacked for imaging and side by side alt-az for visual. Or I could just go for a Mak-Cass and an imaging/standard newt and choose which one to mount up for whatever imaging work I decide to do on the night. The newt would cost a bit less than the refractor.

Either way, I'll have a mak-cass with a long focal length for killing planets (if anyone thinks a rumak is the go and knows of a good one around the same price as the SkyWatcher let me know), then a scope for wide field dso's. Exposure times compared to the newt I'm guessing will be longer with the refractor because of the smaller aperture, but at least I can mount them both at the same time.

Hmmm decisions, decisions, decisions...

I'm appreciating all the feedback though! Helps a lot to get opinions from the pros.

[Camelopardalis (Dunk)]

If I were you, I'd get something small and short for getting started with imaging... ED80 or similar, you'll also need the flattener/reducer too. Then stick that on a good mount, HEQ5 or EQ6 should do well with a small scope, but you get what you pay for with mounts....

Then separately get a 8" or 10" Dob for visual... means you can be using the a scope visually while you're imaging something else

What's your intent with the Mak?