EQMOD vs. Celestron NexStar?

I'm looking to buy a simple mount to get started with astrophotography for the next year, until I have the dough to buy a high end mount (i.e. 10Micron GM1000HPS, Paramount MX, etc.) Filtered the options for a short-term interim mount down to either a used Celestron CGEM or an Orion EQ-G (or maybe a Skywatcher EQ6, if that's what's available used).

Only real questions I have left have to do with the controller. Seems Celestron's NexStar offers a better alignment routine that keeps setup and alignment pretty simple. I've heard about EQMOD for the EQ6/EQ-G style mounts, and I read a bit about the software tools available in that suite. Some of it seems intriguing, especially the EQMosaic tool.

I'm not really sure how EQMOD compares to NexStar, though. Especially the alignment routine. Is aligning a mount easy with EQMOD? Is it accurate?

Thanks!

I've never used NexStar so I don't know how that works, but I'll comment on EQMOD. I have EQMOD installed and connected to my Atlas EQ-G. Along with this I have astrotortilla and Cartes du Ciel instaled . Once polar alligned , I slew to a target which is always off. I let my camera take a snapshot of the area, Astrotortilla plate solves it, and tells EQMOD to move the mount. This repeats until the target is centered. After the first one gotos are dead on for the night.

Without Astrotortilla and a camera, use your choice of planetarium software along with EQMOD to do your go to alignment. I use Cartes du Ciel which is free. Just click on an a star, slew to it, use the EQMOD controls to center the star in you eyepiece, press the sync button in Cartes du Ciel. Do this for a few stars and your gotos will be dead on. The combo of EQMOD and Cartes du Ciel let you align on any star, and as few or as many as you want. I haven't used the mounts hand controller in almost two years now. I find that EQMOD and CdC are a joy to use.

What proteus5 said. I've heard NexStar is more capable than SynScan, but EQMOD is going to be very hard to top.

I've never used NexStar so I don't know how that works, but I'll comment on EQMOD. I have EQMOD installed and connected to my Atlas EQ-G. Along with this I have astrotortilla and Cartes du Ciel instaled . Once polar alligned , I slew to a target which is always off. I let my camera take a snapshot of the area, Astrotortilla plate solves it, and tells EQMOD to move the mount. This repeats until the target is centered. After the first one gotos are dead on for the night.

Thanks guys, very useful info! I know of Cartes du Ciel, but I hadn't heard of AstroTortilla. Plate solving for alignment sounds pretty awesome. I've downloaded it, will give it a whirl once I get a mount. (Seems all you need with AstroTortilla and an ASCOM compliant mount? EQMOD isn't actually a requirement, is it?)

I was looking to use AlignMaster before. I'd read some good things about it, and it stated that once you align and verify with AlignMaster, further drift alignment is no longer even necessary...your perfectly aligned. The difference is AlignMaster seems to still be a rather manual process. Does AstroTortilla do the same thing, perfectly align, so you don't have to do additional drift alignment? If so, sounds like a MUCH better process if it is mostly automatic.

Without Astrotortilla and a camera, use your choice of planetarium software along with EQMOD to do your go to alignment. I use Cartes du Ciel which is free. Just click on an a star, slew to it, use the EQMOD controls to center the star in you eyepiece, press the sync button in Cartes du Ciel. Do this for a few stars and your gotos will be dead on. The combo of EQMOD and Cartes du Ciel let you align on any star, and as few or as many as you want. I haven't used the mounts hand controller in almost two years now. I find that EQMOD and CdC are a joy to use.

That sounds pretty similar to NexStar All Star Alignment. I think I'll go the AstroTortilla route, though. If I can automate as much of the process as possible, that would be ideal.

Also, it seems like AstroTortilla should work with any ASCOM compliant scope, meaning it should also work with higher end mounts, correct? I had kind of written off a Mach1 GTO, as I'd read a few things on some forums (including CN) that indicated it could be a bit of a pain to align (or at least, align precisely enough for unguided tracking...I guess you could still guide it). If I could Tortillalign it and not have to fiddle with the alignment a lot, then that makes the Mach1 GTO more appealing than a GM1000HPS or Paramount MX given its much lower cost...

http://www.youtube.c...h?v=zQB6UnrTEEM

This is how I align my Nexstar (Celestron) mounts also I use BYE and AT. I have no need for planetarium software to control the mount because I use Nexremote (the HC on pc) and either find the object in its data base or input the location. I do use CDC or Stellarium ect when planning for objects but other than that I don't use it connected to mount.

opps left something out the alignment starts at the 30min mark sorry

opps left something out the alignment starts at the 30min mark sorry

LOL, got it!

Guylain

http://www.youtube.c...h?v=zQB6UnrTEEM

This is how I align my Nexstar (Celestron) mounts also I use BYE and AT. I have no need for planetarium software to control the mount because I use Nexremote (the HC on pc) and either find the object in its data base or input the location. I do use CDC or Stellarium ect when planning for objects but other than that I don't use it connected to mount.

Thanks for the link. I remember watching Forest Tanaka's videos sometime last year...they are really very good. I'll have to watch part two again. He did an excellent job! Part three (which I think he did only recently), where he covered guiding, was very good. He is supposedly doing a post-processing video as well...looking forward to seeing his techniques.

Thanks for the info about NexRemote, too. Does that come with Celestron mounts, or is it something extra you have to buy? (I guess I thought it only came with the CGE/CGE Pro mounts for some reason...)

opps left something out the alignment starts at the 30min mark sorry

LOL, got it!

Guylain

LOL. I think I'm pretty sold on BYEos now (not just because of Tanaka's video). I do like the way he used it to bring the sensor frame parallel to the field of view...very simple and strait forward.

A little off topic, but I read a bunch of older forum threads on ATP vs. BYEos. Sounds like a lot of people like ATP for its rich featureset, but personally I like the strait forward simplicity of BYEos. It offers the key functionality I want, without dumping so many features on me that it makes them all too difficult to use. Soon as I get a mount, you'll be getting another customer.

Jon the NexRemote software comes with the mounts but download the latest edition from the site its FREE. BYE and AT working together works for me 99.9999% of the time, the 0.0001% is operator error

I tried ATP but again to many bells and whistles. Now you talked about mounts earlier what kind of scope do plan on using for your temp setup and will this scope size change once you've bought your high end mount?

BYE and AT working together works for me 99.9999% of the time, the 0.0001% is operator error

Aint that how it always is.

Now you talked about mounts earlier what kind of scope do plan on using for your temp setup and will this scope size change once you've bought your high end mount?

I just want to get started with astrophotography for now. I've been wanting to get into it for years, and I keep finding better and more expensive gear...but that just means I have to save more and more, pushing off the date when I can actually purchase gear, and I never actually get into it. So, in all honesty I don't really care what I get in the short term, so long as I can do astrophotography with it.

I had planned on using my Canon 600mm f/4 L II lens as a scope, however I have been having a hard time contacting someone at Parallax Instruments to get some scope rings made. It's also a bit of a juryrigged setup if you do that, and the only way to focus is the lens' focus ring, which has a fairly short throw and is pretty touchy (I've tried doing non-tracked AP with it, and focusing is the hardest part...I even printed out a bahtinov mask for it, which helps, but it's still tough getting focus to stay exactly where you want it (particularly if you point the lens up by any significant degree...you get some focus shift over time, this lens was really meant to be used with an autofocusing camera body while held mostly horizontal to the ground.)

I've found an Astro-Tech 6" RC astrograph for sale on Astromart, has a focuser and is pretty cheap. Seems like the seller does astrophotography, so I suspect this OTA has been used for that. It's got a short enough focal length to work with the Orion mini autoguider package I just bought, and it can be used with focal reducers for a wider field. It would also work with an OAG if I wanted to, where as my 600mm lens doesn't have enough backfocus to support an OAG. I also gather that the parallax rings for my 600mm lens would probably be more expensive than the AT6RC.

I will pick up whatever CGEM or Atlas comes along with the best price for the most features, I guess. There is actually one Skywatcher EQ-6 on Astromart right now for a pretty good price, I guess that's the same thing as an Atlas EQ-G (don't know much about Skywatcher to be honest...I know more about Celestron, Orion, and Meade.) I'd kind of like a hypertuned CGEM or Atlas though, if I can find one for a good price.

Hence the question about differences between NexStar and EQMod.

As for the future, not exactly sure what I'll get, but the options have narrowed. I think the mount will ultimately hinge on the tube. It looks like Astro-Tech will be releasing a 16" RC Truss soon, and the price is around $7000. Pretty darn good price for such a large scope. I don't really know exactly how heavy that puppy will be, but I expect it to need at least something in the range of a Paramount ME/MX, AP1100GTO, or GM2000HPS. When I first got here I thought I might spend $10k on astrophotography equipment, now it looks like it'll be more like $30k, with the most significant cost being the mount (half the cost or so, really). I will probably pick up an 11" scope in the interim once I've exhausted the capabilities of the AT6RC...maybe an AT10RC or a C11HD. All of this is down the road a ways, though...I don't imagine using a 16" truss on a 150lb mount without having a permanent observatory for it all...and I haven't even begun to figure out what to do about that (can't do it where I currently live, not enough land.)

You misunderstood the difficulty of polar aligning a Mach1.

It doesn't have a multi star model. But it has several polar alignment procedures in its handset. Or just buy the RAPAS and forget about polar alignment routines, the RAPAS is accurate enough by itself.

MY polar alignment issues is because I can't see Polaris and I don't know how to use the Quick Drift Align routine. Also QDA requires several stars close to the zenith and meridian and my balcony roof blocks that area of the sky.

Orion doesn't make any mounts. They just rebadge the Synta / Skywatcher EQ6.

Celestron also is owned by Synta. That said the Nexstar HC is much more capable than the Synscan HC. But EQMOD beats the Nexstar by a mile.

You can also use AstroTortilla to point an AP mount. But AP mounts only use a single star pointing model. So adding stars doesn't make pointing more accurate. If your polar alignment is good pointing will be good. End of story.

While EQMOD pointing gets better the more stars you add to the model, it does not improve tracking. So if you are grossly misaligned, pointing will be accurate but tracking will be terrible. These mounts don't track in both axes. Only in RA.

In other words, multiple alignment stars or not, you still need a very good polar alignment.

You misunderstood the difficulty of polar aligning a Mach1.

It doesn't have a multi star model. But it has several polar alignment procedures in its handset. Or just buy the RAPAS and forget about polar alignment routines, the RAPAS is accurate enough by itself.

MY polar alignment issues is because I can't see Polaris and I don't know how to use the Quick Drift Align routine. Also QDA requires several stars close to the zenith and meridian and my balcony roof blocks that area of the sky.

My concerns about the Mach1 weren't actually based on your issues. They were based on a few other posts from other threads, both here on CN and on other forums. I thought I linked a few of them in my other thread. Anyway, in the long term, if I get a bigger scope, the 45lb capacity of the Mach1 won't serve me for very long anyway...it would handle a C11HD, but I don't even think it would be enough for an AT12RC (which is over 49lb in and of itself.)

Orion doesn't make any mounts. They just rebadge the Synta / Skywatcher EQ6.

Celestron also is owned by Synta. That said the Nexstar HC is much more capable than the Synscan HC. But EQMOD beats the Nexstar by a mile.

Ah, Synta. That's who makes it all. Well, then the Skywatcher EQ6 for sale on astromart just might do it. I guess the only thing I really need to decide is whether I want to pick up a C11HD or AT10RC before I dump $30k on all the really high end stup, in which case I want the CGEM DX for it's 50lb capacity (or maybe the CEM60...still need to see how that one pans out).

These mounts don't track in both axes. Only in RA.

They don't track in both axes, but they can be guided in both RA & DEC, correct? I figure you can either spend a lot of time finely tuning your polar alignment, or you can tune it as best you can in about a 10 minute window, and let guiding take care of the drift for you. It also seems you can slightly imbalance in DEC (eastward, I believe), and only guide in one half of the axis to avoid declination backlash. People get over five and even up to 10 minute guided shots doing that all the time. I would then only have to bother with careful drift alignment if I needed exposures longer than 10 minutes (and I don't expect to be doing anything like narrow band imaging that would require that until I have an STF-8300m+filter wheel in hand...)

HMMMM EQMOD beats NexStar now that is debatable.

...I figure you can either spend a lot of time finely tuning your polar alignment, or you can tune it as best you can in about a 10 minute window, and let guiding take care of the drift for you...

Maybe. IMO, you'll spend much more than this time in post-processing trying to fix imperfections that wouldn't have been there if polar alignment had been better. I'm pretty much a novice, but every decent picture I've taken has been because I was **** about polar alignment (and I *do* guide). With imprecise polar alignment the stars never seem to be quite there.

...I figure you can either spend a lot of time finely tuning your polar alignment, or you can tune it as best you can in about a 10 minute window, and let guiding take care of the drift for you...

Maybe. IMO, you'll spend much more than this time in post-processing trying to fix imperfections that wouldn't have been there if polar alignment had been better. I'm pretty much a novice, but every decent picture I've taken has been because I was **** about polar alignment (and I *do* guide). With imprecise polar alignment the stars never seem to be quite there.

Just out of curiosity (and truly honest question here), about how much time do you spend in drift alignment? Is it around 10-15 minutes, or is it more like 45-60 minutes?

Based on some of the 30- to 60-second exposure procedures I've seen people do with BYEOS, it shouldn't take all that long to perform pretty good drift alignment, such that your P2P PE w/ guiding+pec should be ~2-3arcsec or so. If you get the 60-second initial drift test tracking back across itself pretty precisely, then you should only have to do one round of actual drift for each axis while watching a star drift (or hopefully, not drift) over a 5 minute period. Overall, the grand total time invested should only be about 12 minutes.

I use the video and my setup time is around 20 mins using it. I do add 3 calibration stars in the HC for the mount to have a model of the sky I'm in. Then a few extra mins to let PHD calibrate. I've run upwards of 20min subs from home and at a dark site 30min subs but it takes practice but it also becomes second nature after your going at it after a while

Astrotortilla has a decent polar align routine as well. Me I use PemPro.

Astrotortilla has a decent polar align routine as well. Me I use PemPro.

+1 for both