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Buying first telescope.


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I will be buying my first telescope to use in my backyard (bortle 6)

I wanted a telescope for the last 10 years. I purchased a $50 scope 8 years ago and returned it with in 24 hours. For past 2 weeks, I have been reading about Vespera 2" smart scope ($1500) and Unistellar 4.5" equinox ($2400 after $600 discount this week). I changed my mind now. I am planning on building my first scope instead of buying a smart scope. I know its not ideal but I want a telescope that can do it all: planets, sun, DSO and be portable.

List:
$550 Celestron C6 XLT - 6"

$740 Star adventurer gti

$300 ASIAIR Plus

I cannot decide between these 3 cooled cameras. Please help me choose which one will pair best with my C6 telescope. Or should I just get a cheaper $200 non-cooled zwo camera?:
$800  ASI183MC Pro

$900  ASI553MC Pro

$1000 ASI294MC Pro

Misc:
$57 Celestron EclipSmart Solar filter 6"

Total: $2700-3000

Seems like a lot of money for my 1st scope but I thought if I was planning on spending $2400 on the Unistellar smart scope why not spend a similar amount to build one. Hopefully the go-to function and resolution will be comparable to the new smart scopes.

A few questions:
1. Can the ASIAIR Plus successfully plate solve using only the main C6 scope paired with main ZWO Pro camera? I do not want to use a guide scope and zwo mini camera for guiding as I will be reaching the 11 lb weight limit of my mount.  Specs for C6 scope shows 10 lbs but multiple forums mention its actually 8.2 lbs without guidescope, eyepiece, lens cover. I think I will be around 10.5-11 lbs: with ZWO camera (1 lb), ASIAIR Plus (0.5 lb), C6 (8.2 lbs), cables, etc.

2. Are there any essential accessories not listed above which I will need to start: such as missing wires/cables that wont be included in the box?

3. Which portable battery is good to power all equipment?

4. I want to attach a green laser with remote (0.3 lb) to the scope.  It might be a nice visual aid to see where the scope is pointing at? Will it be easy to mount this?

Sorry for the many questions.

Thanks,
Subspace

Edited by Subspace
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If you're just starting out an apochromatic (apo) refractor may be better as there's generally no issue you can get with them (unless you get a bad scope), paired with a field flattener you can get nice round stars across the camera sensor frame.

The c6 on the other hand is a great scope, I just acquired one and did first light a few days ago just visually though. I used a small guide scope set as my main camera within the asiair and used it to plate solve to find objects easily via goto. I mentioned start with a refractor as Schmidt cassegrains (SCT) require a bit of acclimatisation depending on the temperature before you can use them, they may need collimation adjustments from time to time, focusing is a little difficult to get bang on unless if you use an aftermarket 2 stage focuser (though I didn't find the C6 default one too bad). The 6 inch aperture is also a good start (and highly expensive if it were a apo refractor).

If you're looking to image with the C6, via it's default focal length of F10 you can image planets, you'll need the f6.3 reducer or hyperstar (f2) to get into DSO imaging, and the focal length of the scope shortens with each bit of kit but you have the benefit of a multi purpose scope. Not sure if you can do solar with it though, another member will have to confirm. With my refractor I can do everything with it within reason and optical limits and filters. 

As it's not currently out for many user reviews the SAGTI may not be suitable (Although I do put 6kg on my azgti), it's only rated for 5kg payload, and imaging it's recommended to stay within 50-75% at a push max payload. The c6 with default dovetail, visual back and finder scope is 3.5kg, add anything else to it and it will go over 5kg (mounting rings, plates etc add a considerable weight). If you do not want to use a guidescope unfortunately you have to spend more on a mount which has good mechanics for sidereal tracking. For imaging it's recommended to use a guidescope with attached guide camera, especially if each image is going to be a long exposure (30s plus). You don't need a guidescope/cam for planetary work/lunar/solar.

The asiair I would say is pretty much essential if you want ease of use, unless you want to save money and use an existing computer, I didn't want the hassle, it's much easier for me to use my phone. There are other options like the raspberry pi with stellarmate or astroberry (the asiair is a modified raspberry pi), the phone interface for the asiair app is just so easy and convenient to use.

Of the 3 cameras you have listed all are good, the 533 and 294 are newer than the 183, the 183 does have amp glow but it calibrates out. The 294 does suffer from odd flat file imaging at a specific gain setting but most users work around that. The 533 is appealing due to minimal-no amp glow but it's a square sensor if you are willing to work with it. The newer cameras have larger full well depths which is great for capturing more dynamic range (range of colour levels) but if you look at the technical graphs these FWD figures drop down very quickly approaching 100 gain or so. I don't think any of these cameras would be a bad choice and a step up from a modded dslr. If you're buying new/seller kept it as new all the cables should be within the box (12v power cables, usb3 cables).

You may need an EQ DIR/EQ MOD cable which connects from the asiair to the mount, though I'm unsure. With my azgti I use an rj12 ended EQ DIR cable with the usb end plugged into the asiair, with my gem28 the usb from the mount hand controller plugs straight into the asiair usb.

If you haven't used it already I suggest you look at the telescopius website and the telescope simulator on there to input scope and camera parameters to check how it frames up on targets which you can search for, the pixel scales also have to match (I personally don't read too much into that aspect).

I use a Celestron Lithium LT which powers my setup either azgti or gem28 for 3-4 hours. It only has one 12v out though, the usb can't be used at the same time, any other 12v equipment I power via the asiair output ports.

Laser should be easily mountable but you should check for air traffic around your location as it's illegal to be using lasers in the vicinity of aircraft, a red dot finder or better yet a Rigel quikfinder or telrad will achieve better.

The all in one solutions seem expensive but it's all the equipment you need fixed into one unit, easy to setup and let it do its thing. The joy in putting a setup together yourself and seeing the results after resolving all your issues (you WILL GUARANTEED get issues) I personally find more rewarding, I can always upgrade/change an element of the setup afterward if I wanted.

Sure there's more to add but a lot there for you to digest. Also consider the used market, you'll save a lot of money which can be used for more purchases (you WILL BUY MORE).

 

Edited by Elp
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Posted (edited)

Thank you for the reply.  I decided against refractor scopes due to higher weight, cost and smaller aperture.

Can you list any popular mounts with bigger payloads that has go-to function and allows ASIAIR Plus to control it?  My original plan was to have somewhat portable scope.

Does the ASIAIR Plus plate solve one time for the night or does it need to continuously plate solve while taking images? 
I guess I will need a guide scope if it requires continuous plate solving in order to track and let the main scope capture?
My initial thought was to reduce weight by using C6/ASI533 as both my guide scope and main scope to do both guiding/tracking and imaging at the same time. I don't know if this will work since I haven't used them before.
I guess the other option is to use the SAGTI wifi go-to function instead of plate solving. I believe it can track after aligning with the SynScan app. Someone in reviews mentioned the app can work with Stellarium. Can the Stellarium app on the phone control the SAGTI mount?

Would the SAGTI mount break or gears go bad if its over by 1-2 lbs? Or is it that it wont track as well?

Edited by Subspace
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9 minutes ago, Subspace said:

Can you list any popular mounts with bigger payloads that has go-to function and allows ASIAIR Plus to control it?  My original plan was to have somewhat portable scope.

Does the ASIAIR Plus plate solve one time for the night or does it need to continuously plate solve while taking images? 
I guess I will need a guide scope if it requires continuous plate solving in order to track and let the main scope capture?

The HEQ5 can handle an 8" reflector without issues, as long as it's not windy. Entry-level, but semi-proff quality. And platesolving is something you do once for each target, don't confuse it with guiding. Platesolving is usually done with your main scope and imaging camera, and it's mainly to set up (frame) the target in your camera. Also used in polar alignement and such, but that's another story. If you buy a 6" or 8" reflector, you can use the 50mm finderscope as guidescope. FLO has a set with camera and adapter for a reasonable price. As for camera; I use a DSLR. I want a dedicated astrocamera, but that will cost the same as the rest of my rig combined. So untill further, I have a collection of three Canon's, like to keep things simple.

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1 hour ago, carastro said:

An 8” Newtonian on an HEQ5 is not really sturdy enough for long exposure.  Any slight breeze will knock the image.  

Naahh... I do well, have an obsy. And as I said, it's borderline! Live in Norway, and when it's clear and dark it's most often also cold and still. It's just the stock HEQ5/200PDS rig, but I've had guiding in the low 0.4 RMS, and usually expose 2-3 minutes. I'd say this combo is the best value-for-money, as long as you can remedy the wind, if any!!

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Any mount with motor drives will continue to track (note it's a mechanical process, once the motors set to the required tracking speed it will continue to move the mount unless told otherwise). A guidescope with camera on the other hand is continuously "watching" the stars and sends commands to the respective mount to move a set amount accordingly which ensures a target stays centralised.

If you're not using autoguiding the mount will have to be aligned to a few main stars after polar alignment so the in built star chart data knows the orientation of the scope together with the location data which is input. If successfully aligned then goto will work.

Don't know about the software syncing side as I don't do it, when you're doing DSO you'll be imaging the same target over many nights. Asiair app now has a basic stellarium type function built into it though it's nowhere near as good.

The asiair plate solves whenever it slews to a new target. It does this via the camera set as the main camera. The guide camera only deals with autoguiding. You can't guide and image with one camera only, you need two, or use the one camera to image and use the in built motor drives of the mount to track.

Mounts which usually come recommended are heq5 or 6, ioptron CEM/gem, other people can recommend more. Though I wouldn't consider any of them portable (yes you can lift them and move them about) but definitely not portable as they'll need sturdy tripods and the counterweights. The other newer option is to consider harmonic drive mounts but these are even more expensive.

If you want portable goto have a read of @AstroNebulee s azgti owners thread to see what can be achieved as a portable setup.

Refractors aren't that heavy if you keep below 80mm, though apos can cost a bit of you're not buying used. Good ones can be found below or around the £500 mark. The other issue with the C6 is focal length, even at 0.63x reduced youre still nearly at a metre of focal length, the longer your focal length the more accurate your polar alignment and the better your tracking needs to be when imaging DSO.

If you overload the mount you risk damaging the internal drive parts.

 

 

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I think you may be in danger of trying to run before you can walk.  It also appears that you want one scope and mount to cover all bases. From your equipment list it seems you are mainly interested in imaging.   There is no such thing as a telescope that can do it all. That's why I have four, and four GoTo mounts.

The Star Adventurer seems mainly suited to wide angle imaging with a telephoto lens or small scope.  The 6" SCT (mainly suitable for visual use) does not seem a good match for it.

I suggest that rather than buying an expensive cooled camera you start with a cheaper uncooled one or a DSLR (you may have one of the latter already) and instead of the ASAIR use an existing laptop.

Once you have had a go you will be better placed to judge what you really need to buy.

If you intend to image with a 6" SCT you need a serious mount like a  HEQ5.

Check your local laws before going anywhere near a green laser pointed at the sky.

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