13 replies to this topic

[The0s]

Hi everyone,

 

I'm fairly new to astrophotography (around 5 months of shooting untracked images) and I just have some questions regarding intro EQ mounts and star trackers. I've been looking into acquiring one for a few weeks now, and have so far been leaning towards the Sky Watcher Star Adventurer GTi, as it fits more or less into my budget, is portable (I'll likely be traveling with this mount, backpacking, etc.), and gives some room to grow e.g. autoguiding, etc. However, before making any final decisions, I felt it would be valuable to get the input of people of people who have more experience with this hobby, and as such, I'd like to pose 5 questions (as a note, my current setup is an unmodified Canon Rebel T7 with a 300 mm kit lens):

1. Would the Star Adventurer GTi be a worthwhile investment compared to a cheaper star tracker such as the Star Adventurer 2i and why?
2. In your opinion, what EQ mounts or trackers, within a reasonable price range, would be better investments than the Star Adventurer GTi while still having similar or better functionality?
3. For those who have a SA GTi or other EQ mount, do you have any suggestions or comments that you think would be valuable for a newbie like myself to know about this mount or just in general?
4. Is there anything that you think might be a better investment (better lens, modified camera, etc.) at this stage than an EQ mount/star tracker?
5. Finally (I know it's a lot of questions), in your experience, is it better to buy new or used gear, such as from the Classifieds section here on Cloudy Nights, and how safe is to buy used gear in terms of quality and, you know, scamming?

Thanks in advance for taking the time to read and respond.

[bobzeq25]

1.  Worthwhile.  Motors on both RA and DEC make things like platesolving workable.  Skills that you want to learn.

 

2.  For the price, it's hard to beat the GTi.  More expensive EQ mounts are better.

 

3.  The key to making an inexpensive (honest) mount like the GTi work well is to not overburden it.  That's not just weight, it's focal length also.  Longer focal lengths stress mounts more.  The 300mm lens can work well, going heavier or longer is somewhat risky.  Best left until you've learned the basic techniques with the lens, or something similar (like a Redcat 51).

 

https://agenaastro.c...escope-red.html

 

4.  No.  The mount is the most important part of a DSO imaging setup, not the scope or the camera.

 

5.  No good knowledge, I don't buy used equipment.

 

This will be the best $50 you'll ever spend in DSO AP.

 

https://www.amazon.c...d/dp/0999470949

Edited by bobzeq25, 03 December 2023 - 02:21 AM.

[unimatrix0]

1.  You have a greater range of control on a Go-To mount than a star tracker.  You also got 2 axis  RA and DEC, the star tracker just rotates around on RA.  Go-To mounts also capable of doing what their names suggests, once polar aligned you can do a go-to to an object and once you plate solve that, the next go-to object will be more accurately centered, because the mount updates its internal skymap to compensate for error.   You can also do better guiding with a goto EQ mount, because your guider can control both RA and DEC  to make corrections. Star Trackers are best used with cameras and lens and perhaps the lowest focal length scopes, like a 60mm refractor or 50mm like redcat and a DSLR or mirrorless camera. 

 

2. The standard advice with mounts below a certain amount of money (I put it anything below $1500 in 2023) have their limitations as far as accuracy in tracking and weight capacity and possibly longevity. They work the best with light and short focal range refractors, camera lens. As far as I know the GTI costs around $800 or around I don't have a clue what else is out there for this price. I would say it's one of the cheapest mounts out there.  Honestly, in my experience, the cheaper the mount, the harder to use. But again, if you can't afford anything bigger/more expensive, I've seen others using it with some luck. 

 

3. That really depends on whether or not you have any experience using any mounts, including manual mounts.  Astrophotography is really 3 hobby in one.   Astronomy and experience with telescopes and mounts and the night sky;  photography and understanding how cameras work;  image processing which requires using photo editing software and some creativity.  I would also add, that having experience using various computers and how to connect things and identify computer hardware/software related issues is also essential. If you are lacking any or all these fields, my advice is to hit up some youtube videos and read up on the subjects, because it can be a lot at once. 

 

4. We don't know what you have already, not sure how you gonna do astrophotography without a mount, but having better lens and camera. I mean it's not impossible to shoot from a fixed tripod and maybe a 50mm focal length pancake lens. 

 

5. I don't know, I haven't been scammed there yet, I know it's a lot safer than facebook market or craigslist or ebay, because  you have to get into a conversation with the seller or the buyer. Seeing a high post count and many years of being a forum member is usually the safe bet to buy from. I mean , just don't buy something suspiciously cheap from someone who just signed up yesterday- that's what I mean . 

Edited by unimatrix0, 03 December 2023 - 02:26 AM.

[The0s]

1.  Worthwhile.  Motors on both RA and DEC make things like platesolving workable.  Skills that you want to learn.

 

2.  For the price, it's hard to beat the GTi.  More expensive EQ mounts are better.

 

3.  The key to making an inexpensive (honest) mount like the GTi work well is to not overburden it.  That's not just weight, it's focal length also.  Longer focal lengths stress mounts more.  The 300mm lens can work well, going heavier or longer is somewhat risky.  Best left until you've learned the basic techniques with the lens, or something similar (like a Redcat 51).

 

https://agenaastro.c...escope-red.html

 

4.  No.  The mount is the most important part of a DSO imaging setup, not the scope or the camera.

 

5.  No good knowledge, I don't buy used equipment.

 

This will be the best $50 you'll ever spend in DSO AP.

 

https://www.amazon.c...d/dp/0999470949

Thank you for the speedy reply, I'll look into the book you suggested. What more expensive EQ mounts were you specifically talking about, if you don't mind sharing?

[The0s]

4. We don't know what you have already, not sure how you gonna do astrophotography without a mount, but having better lens and camera. I mean it's not impossible to shoot from a fixed tripod and maybe a 50mm focal length pancake lens. 

Thanks for the advice. Sorry, I didn't make it super obvious, but I'm currently shooting untracked with a stock Canon Rebel T7 (2000D) and a 75-300 mm zoom lens.

[rj144]

I recommend the Iexos 100 mount.  It's the only mount I use.

 

Just finished this (from Bortle 8/9):

 

[orbman]

I've been using a Star Adventurer 2i for more than two years now, and have gotten good results with 50mm, 200mm, and 100-400 at 400mm with a DSLR attached. I also have gotten decent planetary results with a 1300mm OTA collecting video streams. The hardest part is finding the DSOs, and I have resorted to mounting an iPhone on my camera hot shoe, and use Stellarium to help me locate my DSO target. If the GTI model were available then, I would have gotten that instead. Here's a montage of some of my results using the 2i (a few of the photos pre-date my 2i). Now I am going to try the 1300mm OTA (f/12.3) with brighter DSOs.

Attached Thumbnails

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Edited by orbman, 03 December 2023 - 08:03 AM.

[EdDixon]

The Star Adventurer GTi mount has a good rep, but is somewhat limited by the 11 lb payload limit.  For those who dive further into AP work, they end up with one or more scopes of greater weight….and then need a better mount.

 

For real DSO work, the mount is the key part.  Most end up with a heavier EQ mount that handles GOTO, guiding, etc, and more weight.  I use an iOptron HEM27 mount, but also have an iOptron SkyGuider Pro rotator mount.

[BQ Octantis]

Hi The0s,

 

How are you enjoying the hobby so far?

 

Going from untracked to tracked is the key to getting good results out of any lens, so there is no better first investment. But in my experience (having myself started with the Canon 55-250 kit) you'll quickly want to upgrade the kit lens. So it is that upgrade that should guide what mount you buy now.

 

If you're going to stick with camera lenses, the SA GTi is probably all the mount you'll ever need. For shooting really long and deep, you'll just need to add guiding, which the mount will support.

 

But if you want to head into heavier refractor territory, you'll quickly reach the GTi's 11 lb capacity, and you'll need a mount in the next class up.

 

So the $2000 question is, where do you see yourself in the hobby in another year?

 

Cheers,

 

BQ

[orbman]

I've been using a Star Adventurer 2i for more than two years now, and have gotten good results with 50mm, 200mm, and 100-400 at 400mm with a DSLR attached. I also have gotten decent planetary results with a 1300mm OTA collecting video streams. The hardest part is finding the DSOs, and I have resorted to mounting an iPhone on my camera hot shoe, and use Stellarium to help me locate my DSO target. If the GTI model were available then, I would have gotten that instead. Here's a montage of some of my results using the 2i (a few of the photos pre-date my 2i). Now I am going to try the 1300mm OTA (f/12.3) with brighter DSOs.

In 2022, I wrote up a brief tutorial on how I use my SA 2i, and posted it on my web site:

 

http://www.faintich....photography.htm

 

There are a few changes that I have made since then. 1. I no longer use my homemade right angle viewer for polar alignment, as I can do a better job looking directly through the polar alignment optics. 2. PS Align Pro now has a feature to rotate the reticle in the app to match the reticle orientation in the SA 2i. 3. I replaced the hot shoe iPhone mount with a sturdier mount than shown. I replaced it with an old hot shoe flash extender, and super-glued an iPhone shell to the extender.

[orbman]

In 2022, I wrote up a brief tutorial on how I use my SA 2i, and posted it on my web site:

 

http://www.faintich....photography.htm

 

There are a few changes that I have made since then. 1. I no longer use my homemade right angle viewer for polar alignment, as I can do a better job looking directly through the polar alignment optics. 2. PS Align Pro now has a feature to rotate the reticle in the app to match the reticle orientation in the SA 2i. 3. I replaced the hot shoe iPhone mount with a sturdier mount than shown. I replaced it with an old hot shoe flash extender, and super-glued an iPhone shell to the extender.

Also, I now prefer to power the SA 2i through the 5V DC USB port. The batteries are sometimes hard to get good contact to run the unit, and even harder to remove from the battery compartment, especially the two end batteries. As I am hanging a bum pack around the tripod legs containing additional weights to stabilize the mount, adding a small Anker battery backup power supply to the bum pack and an inexpensive connecting cord makes using the unit easier. Furthermore, with no batteries in the unit, doing my initial polar alignment using my iPhone is easier. I think that the batteries installed in the unit create a small magnetic field, even with the SA 2i turned off.
 

[bobzeq25]

Thank you for the speedy reply, I'll look into the book you suggested. What more expensive EQ mounts were you specifically talking about, if you don't mind sharing?

The mounts I often recommend are:  The iOptron CEM26, the iOptron GEM28, and the Sirius HEQ5-Pro.  All about $1400.

 

They'll take you to 600mm and 12 pounds, and it would not be a bad choice to start with one of them and your lens.  There is no such thing as "too good" a mount, only too expensive or too heavy.  _Everyone_ struggles to get good tracking.

 

One of two big beginner mistakes is skimping too much on the mount.  This hobby is complicated and hard to learn.  You want equipment that makes it as easy as possible to do that.

 

Here's a more basic book.  Scroll down to the picture of the extremely experienced author.  That's a $600 70mm refractor (420mm) on a $1400 HEQ5-Pro.

 

https://www.astropix...bgda_index.html

 

He did not make a mistake.  He did not choose those because he had them lying around.  For $2000 + camera, that's an ideal setup to start with.

 

It's unintuitive how important the mount is.  How good a mount you need.  What such a mount costs to build.  It's a complicated precision machine.  One problem with getting a used one is that it's a beginners mount, and often treated roughly by beginners.  Buying a $9000 Mach 2 used is not risky.  Buying a used $1400 CEM26 is.

Edited by bobzeq25, 03 December 2023 - 11:34 AM.

[JF1960]

I would just try your luck with a used StarAdventurer 2i for now.  You still need a lot of additional equipment to get the most out of any EQ mount.  Learn how to polar align and locate DSO targets in the sky.  You can still shoot light and calibration frames and start to learn how to process them.  This will give you enough learning and results to decide if you want to go further or not.  This hobby is expensive.  If you really become hooked on the hobby using the star tracker, your next step is  to buy a good mount as everyone suggests and build from there.  Add a nice wide field refractor, guiding and software, plus a cooled astrophotography camera.  Before you know it, $4000+ will be spent.   That’s why I suggest starting small now.

[danny1976]

Would the Star Adventurer GTi be a worthwhile investment compared to a cheaper star tracker such as the Star Adventurer 2i and why?

As long as you keep the weight of telescope+cam+accessories under or around 5kg you're fine with the Star Adventurer GTI.

I even sometimes use a TS Optics CF90 just to see how it handles. You will need to buy an additional counter weight or else you won't get it balanced in RA. Dec is no problem.

And it does just as well as my eq6r. Just don't use it when there is strong wind or else you get serious spikes in the guiding graph while the eq6r is more stable in those circumstances.

 

The GTI uses the same Ascom Heq5/6 driver as the eq6r so you're connected in no time in APT.

 

Edited by danny1976, 04 December 2023 - 11:48 AM.