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EQ Mount for Long Exposure AP

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#76 mpgxsvcd

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Posted 01 November 2013 - 09:08 AM

I'm so happy for those that can buy a Mach 1 out of the gate. For the rest of us, we have to grow into this hobby and manage making our mortgage payments in the process.


I'd like to add to this, that some of us are getting up there in years and are a bit creaky in the joints, so mounts like the Atlas and CGEM (41 lbs for the head) are impractical unless we get an observatory--which is even less practical. I would love more muscles or a place for an observatory, but neither is in the cards.

It would be nice if we could get people to answer the question in terms of *roughly equivalent* mounts to what is suggested. For example, if someone asks about an AVX, I'd think that a Sirius, a CG-5 or EQ-5, a ZEQ25, an iEQ30 or a GM-8 would be reasonable alternatives to talk about in the sense of *approximate* finances and weight class (though some might be too expensive and others not up to par). Ranking choices between those would be more helpful than knowing of greater mounts that are out of the competition class.

And yes, I accept that this limits me, perhaps severely. But it doesn't stop me from wanting to become very good *within* my limits.


Well said.

#77 CounterWeight

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Posted 01 November 2013 - 11:22 AM

I think folks should calm down a bit - don't know if I'm considered a 'purist' or any of the other acerbic tags but my 2 cents was at the start, so my 3rd cent here.

It is always more difficult to advise responsibly someone who bought a scope FIRST and then said I want to do long exposure imaging but can't necessarily buy what they might benefit from most with remaining disposable income.

What I find funny is the comment about IOptron, have you looked at where your other choices are made? Guess what. I'll add that maybe your scope was made there too.

As a general plea I'd ask folks not to 'bash' by country of origin. There are far too many people here that would be on the sidelines if you were to somehow cut out the offerings from China. And frankly all the lower end gear. So try being thankful they understand our expectation that we get it all for a song and dance if that, and they are trying in a market nobody else is, and IMO there is a LOT of really nice toys for us - THANKS TO THEM. Without them almost no-one would be here. And too I'd ask not to be acerbic about A-P and SB, ASA, 10 micron who are delivering fantastic products to us which are truly 'hands off' but they want to be paid for all that attention to detail.

In the lower end and mid range mount range if you want to do A-P you are going to become more intimate with the mount. Maybe a little more than you desire, but I do not see that as a bad thing if it will give the results you are after. Read up all you can in the mounts forum. It is these mounts that provide for most of the activity, and there is a lot of great information there. This post may have been better placed there?

But to responsibly from experience say something is or is not up to task is just being honest. I think and hope folks appreciate that anyone is willing outside the sales and marketing staff at so and so to take the time.

Imaging is largely about the mount and not the scope, or even the imaging device. Call it non intuitive or whatever else you like but think about it. The mount holds and points the scope and imager. Any, and I mean ANY issue a mount has will show up in the image - no way out of it. This is why I say it's backwards here. By and large once you get your imaging / optics 'set' you just focus and don't expect a lot of variance, and that is a somewhat safe assumption. The mount, possibly same can be said, polar align and invoke auto-guiding and then... well a lot can show up, and it can be very different seeming, though the cause(s) may be an invisible common denominator.

Sure you can hypertune and toss bad subs and get a good or even great image. But the fact remains that it is an imaging system and the mount is the most important part of that system. So the mounts forum is where I'd spend my time, and I'd read everything I could going back as far as possible.

Don't be fooled by all the pretty pictures. It takes a lot to make them or even one. :) We are lucky here to have the great folks (me included) that do give advice. Maybe there should be another forum for 'ADVICE I WANTED TO HEAR' but there isn't.

But there is a tremendous amount of experience and 'real world hands on' here and in the mounts forum that is free, from enthusiastic folks that love this hobby and desire to share from their often hard came by experience.

Heuristically there are a lot of mounts. First sieve 'cost' filters out some. Second sieve 'telescope type /weight' filers some. Third sieve 'long exposure imaging'... (I'm going to assume you don't mean that the way we do by long meaning over 10 minutes) a far more difficult sieve to pass. Fourth sieve 'easily portable' may further limit...

What makes even a bit more difficult is all the marketing and 'paper whipping' jargon and euphemistic specifications and as I mentioned expectations. No doubt there are folks that want your $$ and that should not come as a surprise.

To me that is where forums like this are worth their weight in photons. Much is possible, it just might be a little more effort than you thought, and you have a lot of well meaning help.

#78 Stelios

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Posted 01 November 2013 - 12:20 PM

but in the end I live in a Camry/Prius world...


which is after all a long step up from a Pinto, Vega, or Gremlin. :cool:


Yes. I don't really think you can do AP on a Gremlin budget. Not unless you exclude the cost of camera, laptop, adequate computer and processing software. People who *have* all those to begin with, are probably not Gremlin drivers unless it is by choice...

#79 mpgxsvcd

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Posted 01 November 2013 - 12:27 PM

Imaging is largely about the mount and not the scope, or even the imaging device. Call it non intuitive or whatever else you like but think about it. The mount holds and points the scope and imager. Any, and I mean ANY issue a mount has will show up in the image - no way out of it. This is why I say it's backwards here. By and large once you get your imaging / optics 'set' you just focus and don't expect a lot of variance, and that is a somewhat safe assumption. The mount, possibly same can be said, polar align and invoke auto-guiding and then... well a lot can show up, and it can be very different seeming, though the cause(s) may be an invisible common denominator.

Sure you can hypertune and toss bad subs and get a good or even great image. But the fact remains that it is an imaging system and the mount is the most important part of that system. So the mounts forum is where I'd spend my time, and I'd read everything I could going back as far as possible.


This is the only part of your post that I disagree with. All of the components matter. The focal ratio of the scope affects your imaging duration and your focal length. Your focal length and imaging duration affect how visible tracking errors are.

Tracking errors are affected by the balance of your system, Periodic Error, Polar Alignment, temperature, humidity, and whether you guide or not.

Guiding is affected by the flexure in your system, the focal ratio of the guide scope, and how far the guide star is from your object of interest.

And that is a simplified version of what is really going on. I could never name absolutely everything that is a factor.

The mount really only affects your tracking motion and the Periodic Error. Those can be huge portions of your overall error if they are bad or they might be insignificant if they are good. If all of the other components can compensate for the Periodic Error then it might not be an issue at all.

For instance if you have a really fast scope with a super sensitive camera you might be taking very short subs that make periodic error insignificant. You also might have a guiding system or mount that is very accurate and means that your Periodic error can be corrected.

To say that the mount is all that matters and the more you spend on it the better your results will be is misleading. That is putting a band aide on a wound that might actually need stiches and antibiotics. Sure you can cover up the wound and pretend it is going away. However, in the end when you pull the Band-Aid off the wound will still be there.

The best thing is to analyze exactly what all of your issues are and attempt to correct each one of them. If your subs are really long then try to determine if you can make them shorter. If your periodic error is very high then attempt to alleviate it with guiding if that is less expensive than buying a new mount.

So many people go right for the most expensive mount and think their problems are all solved when in reality they may have only corrected one issue that really didn’t need to be corrected. Then they forgot about everything else that really did need to be corrected.

#80 mpgxsvcd

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Posted 01 November 2013 - 12:29 PM

but in the end I live in a Camry/Prius world...


which is after all a long step up from a Pinto, Vega, or Gremlin. :cool:


Yes. I don't really think you can do AP on a Gremlin budget. Not unless you exclude the cost of camera, laptop, adequate computer and processing software. People who *have* all those to begin with, are probably not Gremlin drivers unless it is by choice...


Forget a Gremlin budget. Too rich for my blood. I do it all on a mid-range bicycle budget. :shocked:

#81 shawnhar

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Posted 01 November 2013 - 02:17 PM

Hey! I got some pretty good images from my Pinto! :grin:

#82 TimN

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Posted 01 November 2013 - 04:26 PM

Two years ago I was in the same position as the OP. I got a good deal on a Skywatcher 120ED and only after I bought it did I start looking at mounts etc. I did what Jim suggested and spent some time on the mount forum. I had 3 requirements: 1. it had to handle my scope 2. It had to be portable - I'm 66 years old so Atlas types were out of the question. 3. It had to meet my budget.

I found the best combination that met my 3 requirements was the HEQ5 - Sirius -. I really couldn't carry anything heavier and its price seemed reasonable. EQMOD was a nice bonus. I also contacted some members directly that used my scope on this mount and they all assured me it would be ok. Some were even using it with AT8RC's without a problem.

So, I bought one and I haven't had a problem using my 120mm scope, DSLR and 50mm guider. I have just moved it into an observatory but haven't felt the need to upgrade even though portability is no longer an issue.

I haven't tried other mounts to compare but based on initial research and 2 years of use, I'm very happy with my HEQ5.

#83 Stelios

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Posted 01 November 2013 - 05:11 PM

You sound eerily like me, and I'm also reaching the conclusion that the Sirius will be my next mount when my skills are up to moving to longer focal lengths (hopefully next year).

#84 bmwbiker

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Posted 01 November 2013 - 05:41 PM

As beginning imager I'm very happy with my AVX piloting a C80ED and now auto-guiding an ATRC6. Its the right size for quick setup on my small back deck. Go To is spot on provided my alignment is right. AS polar align is great. (Polaris is blocked from view) I was pushing >60sec subs unguided. And I'm at 5-6 minutes guided with the 1370mm AT6RC. Could I have purchased a better mount sure, but I've got north of $2k invested in this endeavor (at budget).

Starting out doesn't require buying the best and at least for my initial efforts the AVX (and the rest of the setup) is more than good enough. Even if money wasn't a consideration acquiring the absolute best equipment doesn't guarantee nor is it a prerequisite for success.

#85 Raginar

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Posted 01 November 2013 - 08:54 PM

BMWbiker, you got some pictures? I'd love to see your astrobin account.

#86 nodalpoint

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Posted 01 November 2013 - 09:06 PM

BMWbiker, you got some pictures? I'd love to see your astrobin account.


Hey Raginar, here's M31 I shot Monday night using mostly the same equipment as BMWbiker - AVX mount, C80ED and an old Nikon. Two hours of 300 sec. exposures made in below freezing temps. Threw out a couple subs due to satellite trails and a high cloud moving through.

Keep in mind I started in September, have only been out about ten times, and am very new to this kind of processing and easily see my flaws, but I'm happy to compare photos taken by fellow low-time beginners with other equipment.

Posted Image

#87 Madratter

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Posted 01 November 2013 - 09:10 PM

I would not have hesitated to put a 80 ED on my CG-5 let alone an AVX. I think it would have made a terrific match. I would have been beyond delighted getting an image that good my 10th time out. :)

#88 bmwbiker

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Posted 01 November 2013 - 09:42 PM

BMWbiker, you got some pictures? I'd love to see your astrobin account.

I'm still struggling with post processing. My final images tend suffer from noise. I haven't bitten the bullet for PS or anything else yet.

This thread does have an image of M31 with C80ED on a AVX unguided.
http://www.cloudynig...Board=low&Nu...


#89 Raginar

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Posted 02 November 2013 - 09:17 AM

MR hit it in the head. My favorite recommendation for a noob would be a CG5 and a ED80 with a DSLR and a finder guider rig. Simple enough to get good wide fields and cheap enough to figure out if you wanna go farther.

Nodal, pretty. You should make an astrobin account so I can follow you :)

BMX, your data is good. If you go to my astrobin you'll see my first pictures from about 2 years ago. They're... Horrendous :)

#90 Raginar

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Posted 03 November 2013 - 12:24 PM

Trav, how did the mount fail you? Something that you did or firmware related?






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