ICEINSPACE
Moon Phase
CURRENT MOON
Waxing Crescent 11.3%
|
|

04-09-2012, 11:04 AM
|
Registered User
|
|
Join Date: Sep 2012
Location: Torquay
Posts: 60
|
|
Newbie equipment feedback
Hi all,
I'm new to this area and have been doing as much reading as I can on the subject to get myself up to speed. I'm nearing the "commit" stage in purchasing some equipment but I thought I would put it out there for some feedback as I haven't found a lot of stuff on the internet in particular about the mount and it's capabilities for astrophotgraphy with I guess a mid-field scope.
The scope I'm looking at is the TSapo65q
http://www.teleskop-express.de/shop/...eld-diam-.html
Some of the sample shots I've seen are pretty amazing and so far mostly positive reviews other than some issues with the cold.
The mount I'm looking at is the Skywatcher EQ3 synscan
http://www.skywatcher.com/swtinc/pro...1=3&class2=304
It is significantly cheaper than the EQ5 equivalent (about $160) and I am wondering ifthe EQ3 would suffice at this stage for what I want.
The EQ3 load raiting is well over what I would have for my initial startup (2.8kg for the scope and my sony Nex camera is only ~0.3kg so I am not so concerned about that, but one of the issues that has been brought up is that the accuracy of the drive / mount may not be good enough for the scope?
At the moment, my budget has already gone above what I originally wanted to spend cause I figured I would get a good scope to start with. On top of this, I will need to get at least a 90 degree star diagonal and at least a couple of eyepieces, plus the T2 mount so it's adding up price-wise! I've also found that it is a lot cheaper to buy this stuff in Germany and have it sent over than it is to purchase here. For the EQ5 + scope I'm getting around au$1300 shipped compared to $1135 for the EQ3 + scope. I realise it's not a huge difference, but I am already over budget.
Thanks for looking,
Matthew
|

04-09-2012, 11:42 AM
|
 |
Registered User
|
|
Join Date: Feb 2007
Location: Melbourne, Victoria
Posts: 1,053
|
|
I think most people would agree that the mount is actually more important than the scope.
I would go an EQ5 rather than the 3. Your weights calculations suggest you are getting up to its limit already such that you couldn't add a guidescope without probably going over the weight allowance.
Astrophotography is a money pit and the accuracies and tolerances not as forgiving as visual.
Why not try a secondhand ED80 and EQ5 which would probably come in under your budget. I think there was one here recently for the $1000mark.
niko
|

04-09-2012, 11:52 AM
|
 |
Registered User
|
|
Join Date: Nov 2009
Location: Box Hill North, Vic
Posts: 1,838
|
|
Thats an interesting combo Mathew.
But I don't see any reference to guidescopes or an OAG in your list.
have you considered autoguiding?
Autoguiding, to a certain extent corrects drive errors and helps with getting longer exposures. Not sure how well it'll work with the EQ3, but if you wanted to save weight, you might have to look at an OAG rather than a piggy back scope. I'd say that'll bring you very close to the 3.8kg limit. cost wise you'll have to add in another $280 odd for the guide camera unless you want to use a modded webcam, and the cost of an OAG or a finder guider.
Without guiding, you may not be able to get exposures longer than a minute or two before you see star trails.
Since your payload will be pretty light, less than 5kg's, you might have other options like the Astrotrac or similar portable mounts that support autoguiding.
http://www.teleskop-express.de/shop/...ST-4-port.html
http://www.flickr.com/photos/markpayne1/5383859201/
Weight: 1 kg (2.2 lb)
Load capacity: 15 kg
good luck.
Last edited by alistairsam; 04-09-2012 at 12:08 PM.
|

04-09-2012, 12:34 PM
|
Registered User
|
|
Join Date: Sep 2012
Location: Torquay
Posts: 60
|
|
Thanks guys for your input. That astrotrac looks interesting but i can see the $$$ piling up haha! I still need to get a tripod on top of the cost of the astrotrac and for me, being a beginner, I was interested in the goto facility to help me learn about where things are and get me going faster. I guess I was thinking that if I could align the mount, then the goto would do all the scoping for me?
I will look up this OAG business too. A lot of the images I've seen are stacks of only 30s through to 2 min which look pretty good. My camera also has a high ISO rating (25600) and my understanding is that when you stack images, the random noise introduced by the high ISOs gets flattened and all but removed.
Appreciate your thoughts.
Matthew
|

04-09-2012, 01:44 PM
|
 |
PI popular people's front
|
|
Join Date: Aug 2010
Location: perth australia
Posts: 1,291
|
|
Interesting comment about the Goto. The Goto won't teach you where anything is: only a red torch, star charts and a lot of time under the stars looking up will do that.
Try and find everything by hand first time, and you'll learn your way around the sky much faster.
Cheers,
Andrew.
|

04-09-2012, 02:11 PM
|
 |
Registered User
|
|
Join Date: Apr 2012
Location: Germany 54°N
Posts: 1,110
|
|
You're right there. A bunch of unguided exposures of 30secs-2mins stacked give very good results and you'll have fun with them.
I'm not convinced though that the EQ3 is a good choice. Not even in the beginning. I'd get an EQ5 if I were you. Because AP needs a real stable mount/scope setup.
The rule of thumb - I'm sure you came across it during your research - is: only put half the weight of the advertised max load onto the mount when doing AP. There certainly is some wiggle room upwards. ..
The EQ5 would give you the option to mount a lightweight reflector (in exchange for the refractor - not on top of it, mind.)
With the EQ3 you are stuck with what you are about to load on right now.
Also: if you really get caught into the vortex and develop Aperture fever, you will not find a buyer for the EQ3. But for sure you'll be able to sell on the EQ5.
TS sells a 6" f/4 newt they call "imaging newt" which is very light.
I know you made your choice for their 65mm Apo.
I just wanted to mention the 6" reflector because it is so very lightweight. (It would be good for deep sky. Not so much for solar system.)
Have fun
|

04-09-2012, 03:43 PM
|
 |
Registered User
|
|
Join Date: Nov 2009
Location: Box Hill North, Vic
Posts: 1,838
|
|
keep a lookout at the classifieds.
Offers like these pop up sometimes.
http://www.iceinspace.com.au/forum/s...ad.php?t=95507
Goto will make life a bit easier to locate objects but it always helps to learn how to navigate the sky by yourself.
Goto's have errors as well which you reduce with syncing objects, it requires good PA as well.
|

05-09-2012, 11:57 AM
|
Registered User
|
|
Join Date: Sep 2012
Location: Torquay
Posts: 60
|
|
Thanks for all the feedback guys. from what I've read about the astrotrac, it looks like I wouldn't need to use a motorised mount at all, which would save me a bit of $ I guess (or even a sturdy photography mount will do). Still, $500 or so for an EQ5, $500+ for an astrotrac and then the scope.. probably a bit more than I want to spend initially. I'll keep an eye out for a second hand mount in the meantime but I think that this sounds like quite a nice combination. The astrotrac will apparently track for just under 2 hours which should be enough to give me some nice images and it seems that the rate of discarded images should be less compared to using the motorised mounts, plus I don't see myself sitting outside for much longer than that in general.
|

05-09-2012, 01:44 PM
|
Registered User
|
|
Join Date: Jan 2005
Location: Mackay, QLD
Posts: 456
|
|
Im just after where you are now...i have commited quite a sum of money to get into AP and all i can say is dont buy just because your budget at the time allows. If your looking at an eq5 save a tad bit more and get an eq6. This mount will last you ages. Nearly everyone i have spoken to says get a good mount first that way you dont have to worry about your mount too much if you change scopes unless you get something huge...
|

05-09-2012, 02:45 PM
|
 |
Registered User
|
|
Join Date: Feb 2007
Location: Melbourne, Victoria
Posts: 1,053
|
|
I'm not sure I understand this statement in relation to the astrotrac
"and it seems that the rate of discarded images should be less compared to using the motorised mounts"
If you just want to do widefields the Astrotrac on a camera tripod would be fine otherwise consider an EQ5 or 6 either will allow plenty of learning and great results. There's always a ready market if you bought an eq5 and then wanted to upgrade
|

05-09-2012, 03:22 PM
|
Registered User
|
|
Join Date: Sep 2012
Location: Torquay
Posts: 60
|
|
Interesting Josh. I had a look at prices for the HE6 mount on it's own and at $1600 I think it's a bit rich for my blood. Since I'm really looking at a relatively light setup (scope = 2.8kg, camera = 0.3 kg and maye the astrotrac = 1kg) Do you still think It's worthwhile to buy such an expensive mount?
No matter which way I add it up, it looks like this is going to be at least a $2000 investment.
At the moment I'm looking at:
Scope +Astrotec from germany = $ 1250
HE5 mount = $500
T2 adapter +not sure, but probably around $50
Stellarvue FET (to attach the scope to the astrotrac) $60
On top of that, a 90 degree star diagonal and some eyepieces $200?
polar scope $?
Did I miss anything? The numbers are slowly slowly increasing haha. I almost get the feeling that no matter what I spend initially, this is going to be a money pit, as niko says.
|

05-09-2012, 03:34 PM
|
Registered User
|
|
Join Date: Sep 2012
Location: Torquay
Posts: 60
|
|
Quote:
Originally Posted by niko
I'm not sure I understand this statement in relation to the astrotrac
"and it seems that the rate of discarded images should be less compared to using the motorised mounts"
If you just want to do widefields the Astrotrac on a camera tripod would be fine otherwise consider an EQ5 or 6 either will allow plenty of learning and great results. There's always a ready market if you bought an eq5 and then wanted to upgrade
|
I've read that people who are using motor drives for their EQ5/HEQ5/EQ6 mounts have to discard 20-40% of their images do to inaccurate motor drives or something about the motor drives not being smooth? The comment was more that if the astrotrac really is as great as it sounds, every image I take (as long as the mount is stable and the polar alignment is alright) should be usable for stacking and I would save some $$ and time by not having to buy motor drives for the mount.
Thanks again for all your patience guys. I really am trying to get my head (and wallet) around all this business.
|

05-09-2012, 03:53 PM
|
Registered User
|
|
Join Date: Jan 2005
Location: Mackay, QLD
Posts: 456
|
|
I look at my purchases this way...especially now i have some experience...when it comes to a major purchase...will it do what i need for 5 years...you get an eq3 and in a years time want to get a bigger scope or add more things such as guide equipment...you will need to then spend more money to get a bigger mount then...
|

05-09-2012, 04:37 PM
|
 |
Registered User
|
|
Join Date: Nov 2009
Location: Box Hill North, Vic
Posts: 1,838
|
|
Quote:
Originally Posted by chaffingbuttock
Still, $500 or so for an EQ5, $500+ for an astrotrac and then the scope.. probably a bit more than I want to spend initially.
The astrotrac will apparently track for just under 2 hours which should be enough to give me some nice images and it seems that the rate of discarded images should be less compared to using the motorised mounts
|
Hi,
From what I've read, I believe you can use the astrotrac and a refractor as in the image link I posted earlier which has an ED80. I don't think it needs another mount. just a tripod.
and the present model supports st-4 guiding.
so it'd be just the astrotrac, tripod, scope, guidescope.
But pls check cause I'm only going by the website. Maybe some astrotrac owners can chip in.
the load of 15kg's sounds deceivingly inviting, that's more than the capacity of an eq5. not to mention portability. But I don't know how polar alignment is done.
|

05-09-2012, 04:49 PM
|
 |
Registered User
|
|
Join Date: Nov 2009
Location: Box Hill North, Vic
Posts: 1,838
|
|
Quote:
Originally Posted by chaffingbuttock
Interesting Josh. I had a look at prices for the HE6 mount on it's own and at $1600 I think it's a bit rich for my blood.
At the moment I'm looking at:
Scope +Astrotec from germany = $ 1250
HE5 mount = $500
T2 adapter +not sure, but probably around $50
Stellarvue FET (to attach the scope to the astrotrac) $60
On top of that, a 90 degree star diagonal and some eyepieces $200?
polar scope $?
|
not sure why you'd need a HEQ5 mount for the astrotrac?? don't you just need a camera tripod and maybe the wedge?
http://www.astrotrac.com/Default.aspx?p=wedge
if you have a heq5, you don't need the astrotrac.
as posted earlier, something like this
http://www.flickr.com/photos/markpayne1/5383859201/
the second hand heq5 pro's are usually around the $700 mark and are very good mounts, you don't really need an eq6 unless you plan to use 10" or 12" reflectors with heavy CCD cameras or 5" or 6" refractors.
I don't see the guidecam and guidescope/oag. you could always add this later on. if you can get 30sec to 1 or even 2min unguided shots with your 60mm scope without star trailing, then you should be fine.
accuracy of the mount and need for autoguiding is also relevant to the focal length.
for wide angle shots with a 400 to 500mm FL, star trails due to tracking errors are less apparent than with longer focal length scopes at 1m or more.
so if you're using the 400mm FL scope, you should be fine without autoguiding for upto 2 mins or more.
|

05-09-2012, 05:17 PM
|
Registered User
|
|
Join Date: Sep 2012
Location: Torquay
Posts: 60
|
|
Hi Alistairsam,
Sorry I seem to be mixing up my mount attacahments in my head. For some reason I thought you could use the equatorial mount for polar alignment and attach the astrotrac on to that but i don't think you can.
From what I can gather, the astrotrac is mountable on a standard tripod mount. To do the polar alignment, they suggest a manfrotto geared head (which is around us$200+ anyway) but I don't see why you can't do this with a simple pan and tilt or ball head. It just won't have the fine-tuning. On the astrotrac website, they sell a kit with the geared head, tripod and ball head ( http://www.astrotrac.com/Default.aspx?p=holiday-deal) but the mount is not rated for high enough load for the scope + camera + mount (around 5kg). The image that you linked it looks like the telescope is mounted directly to the astotrac which is interesting. Also, he has the wedge but that's another $300+
Unfortunately, my current tripod is only rated for 4kg (since my camera and lens is only around 0.5kg) so I'd have to get a new one anyway.
|

05-09-2012, 05:39 PM
|
Registered User
|
|
Join Date: Sep 2012
Location: Torquay
Posts: 60
|
|
Thanks alistairsam.
I confused myself haha! Ok, so I guess I should maybe look for just the HEQ5 pro (with goto) instead of the astrotrac. I do like the sound of that one though as it sounds rather simple to use and I wouldn't then need to go out and buy a whopping great battery to power the EQ5 through the night. That way I can at least get a decent viewing scope too.. although I also have an interest in photography and moving towards photographic-related accessories might not be a bad thing (photography tripod / head etc).
|
Posting Rules
|
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts
HTML code is Off
|
|
|
All times are GMT +10. The time is now 09:44 AM.
|
|