Really just posting this here as I need to have a few posts in order to contact sellers in the classifieds, but can't hurt to have some extra feedback too...! So here's where I'm at.
Bought an 8" Dob back in July or so. LOVE IT. Immediately addicted. I quickly bought a Nikon T-Ring and 2x Barlow adapter and have shot the Moon, the Sun, Jupiter, Saturn, various conjunctions (Moon/Jupiter, Jupiter/Venus), and even got a surprisingly clear shot of the ISS.
Now I'm keen to move on to DSOs. Obviously not going to happen with a manual Dob.
I've basically settled on my next purchase being a goto mount - HEQ5 or heavier as I want to have something somewhat future proof. For now I'll just stick a DSLR + 200mm lens on it, but eventually I'd like to get a decent APO or maybe an 8" or 10" RC.
I've been assured that a DSLR on a HEQ5 will keep me happily occupied for many months. More than that, I'm hoping that I'll get a $1k hobby expenditure past the wife without copping too much flak...
Any suggestions would be welcome, particularly towards what difficulties I can expect once I actually have a mount in my possession and can get started.
looks like you've been with the astro bug! nice one and nice pics.
with a HEQ5 or higher you are probably going to be able to attach your 8" dob tube on top and use that. that will save money on a scope for a while and you may not need to upgrade that at all.
- tube rings for the scope.
- You will need a guiding solution to take longer exposure. this is usually a guide camera and either a guide scope or an OAG.
- coma corrector / field corrector.
- focuser upgrade
I would advise against a RC collimation can be tricky (and expensive). A newt or a ed80 would be a good choice.
Mmmm... think my Dob tube is about 11kg, which with camera & rings etc is probably a bit much for the HEQ5. Might be able to use it for just observing but I actually quite enjoy like the Dob mount for that!
I considered getting something a bit heavier to manage the Dob tube but I kinda like keeping it just for observing. Eventually I'd like to upgrade it to a 12" or 14" and have it just for observing, and a good refractor - the ED80 is exactly what I had in mind, seems to be a very popular choice and perfect for the HEQ5.
I like the idea of fast Newts but have been talked out of them due to weight, collimation & coma hassles - easier to get good results with a refractor.
However I'm keen to see the new GSO truss tubes when they arrive in April... very very keen. Not that I'll be able to afford any of this stuff anytime soon but a man can dream.
My Skywatcher 8" f/5 Newt is 9.5kg. I have a payload for imaging of
around 11.5-12kg inc camera, electric focuser, finder, etc, and my
HEQ5 handles it just fine.
It is actually not easier to get good results with a refractor. Unless you buy a MONSTER refractor[ many many thousands of dollars]
you will need FAR longer exposures to get the same results, which means accurate guiding is more important. A coma corrector is a
one off purchase, and collimation is a brief simple operation once done a few times. The 8" Newt has much better resolution too, and
no amount of exposure time can compensate for that. If you need to use the screen on your camera, and don't have a moveable one,
then refractors can be a pain in the rear end when aimed higher than about 30degrees. My Newt rotates, so wherever in the sky it is
pointing, I can always find a comfortable viewing position. Finally, even a decent 80mm refractor is quite a lot more expensive than an 8" Newt with coma corrector.
raymo
Last edited by raymo; 26-02-2016 at 12:44 PM.
Reason: more text
My Skywatcher 8" f/5 Newt is 9.5kg. I have a payload for imaging of
around 11.5-12kg inc camera, electric focuser, finder, etc, and my
HEQ5 handles it just fine.
raymo
That's good to know! Most people have recommended not going over 70% of the payload limit for AP but glad to hear you can stretch that a little.
My OTA is actually f/6 though so a fair bit heavier, and my camera is full frame too so also a bit heavier, so think it would be closer to 13kg all up. I'm sure I'll try it one day anyway regardless.
Not sure what the belt mod is though..? Was planning to get whatever the current model is, ie with SynScan.
Chris,
The belt mod replaces the RA and Dec gears in the mount with a belt system. This greatly increases the tracking accuracy an turns the heq5 into a more than capable mount.
I have recently completed the mod on mine (took about an hour). Not only is it quieter when slewing but for the first time ever I could take 15min subs with no streaking.
I am also running an ed80 with a dslr. Great scope however a field flattener might still be needed to get a nice flat image. A newt will definitely come in cheaper as Raymo suggested
The belt mod replaces the RA and Dec gears in the mount with a belt system. This greatly increases the tracking accuracy an turns the heq5 into a more than capable mount.
I have recently completed the mod on mine (took about an hour). Not only is it quieter when slewing but for the first time ever I could take 15min subs with no streaking.
I am also running an ed80 with a dslr. Great scope however a field flattener might still be needed to get a nice flat image. A newt will definitely come in cheaper as Raymo suggested
Okay, a field flattener is something I'm not familiar with - will look into it.
Interesting to hear so much more positive emphasis on Newts. I was talked out of them. That's the way I initially wanted to go; I figured it simply has to be easier using less / shorter exposures, right?? Yet too many people said refractor is a better place to start - I guess because they're lighter and have much shorter focal lengths, and it's easier to achieve focus without an autofocuser.
I dunno. I still like the idea of a cheap 6" f/4 or f/5 reflector to start. Regardless it's all months away - probably going to have to wait til the next financial year before I know whether I can have anything for toys...
Last edited by thegableguy; 27-02-2016 at 12:08 PM.
Okay, a field flattener is something I'm not familiar with - will look into it.
Interesting to hear so much more positive emphasis on Newts. I was talked out of them. That's the way I initially wanted to go; I figured it simply has to be easier using less / shorter exposures, right?? Yet too many people said refractor is a better place to start - I guess because they're lighter and have much shorter focal lengths, and it's easier to achieve focus without an autofocuser.
I dunno. I still like the idea of a cheap 6" f/4 or f/5 reflector to start. Regardless it's all months away - probably going to have to wait til the next financial year before I know whether I can have anything for toys...
Hard to beat an ED80 for a beginner. Light, short FL and no collimation. Also easy to balance and heaps of back focus. I bought one as a guider when I first started and ended up imaging through it a lot more than my newt. I was guiding with the newt.
