Avx or NEQ Mount dilemma.... HELP!!!

[souls33k3r]

Hi guys,

As the subject line says, i'm so confused as to which mount to go for.

I am in the process of purchasing my first scope as an Edge HD 8" (don't judge me yet) with AVX as the mount which comes as a package. From what i first noticed, it's a beast of a scope and a beast of a tripod with a descent size EQ mount.

Now the purpose of this equipment is to get what's better in optics for lunar and planetary objects and then moving swiftly on to DSO for both visual and imaging.

I'm already thinking of buying my next scope as a refractor for DSO imaging but i'll make do with what i've got for as long as i can and then open up my wallet for that.

Now since i'm buying EdgeHD 8" with AVX mount as a package, i'm also buying all the necessary accessories with them. In total it's costing me £1900.

But i'm getting so confused about the AVX mount and below are the reasons:

1) Some people have no issues imaging with it and some have had nightmares

2) I'll most probably not be going any bigger than the 8" and an 80/100mm refractor in future

3) EQmod or not to EQmod

4) Stepper motor vs servo motors

5) Shall i go for a NEQ6 which is cheaper than CGEM (which i've heard from a reliable source is going to be ditched) which will mean i will lose the package deal cost and pay lots extra

So like i said, i'll be doing both visual and imaging (nothing the sorts of having them published in a news paper but something i'll be happy with like getting the full thing and the details etc). Obviously don't want to spend much too. Don't own a car so travelling with the scope for now will be very minimal and even when i do, i'll be using a truck trolley sort to move it around so doing this once every month or so. Mostly be doing this in my light polluted back garden in Barking.

As you can imagine, i'm so confused. I just don't want to end up buying the mount and then regret when i didn't go for the other one.

I hope you understand what i mean here

[ChrisLX200]

The AVX would be OK for visual, or even AP with a small refractor, but AP with an 8" SCT... you'd be making life hard for yourself. The AVX is not renowned as an imaging mount but like I say, under some circumstances you can make it work. Personally I would go for the NEQ6 based on evidence of many owners already successfully using it for both visual and AP. The AZ-EQ6 GT might be even better if you want to combine visual and AP, an EQ mount does tend to put the eyepiece is some awkward positions whereas in AZ mode it's a lot more simple. The type of motor used is largely irrelevant, just consider the overall performance of the mount rather than the engine powering it.

ChrisH

[ollypenrice]

Consider the accuracy needed to autoguide a C8 Edge for imaging. In order to do this you need to know your pixel scale. You can calculate it here. http://www.12dstring.me.uk/fov.htmI don't know what camera you intend to use but if you would like a glib assessment of pixel scales and their relationship with the guiding and seeing needed to support them I'll oblige - but these are my personal rules of thumb.

Less than 0.5"P/P. Nuts. I wouldn't do it.

0.5 to 1.0. Premium mount and good seeing - just about worth a go. Permanent setup vastly to be preferred.

1.0 to 1.5. Difficult-ish but nice if you can make it work.

1.5 to 2.5. The sweet spot with low pain and decent resolution.

2.5 to 3.5. Worth doing if you are going to get a cracking field of view out of it.

Others will doubtless disagree!

Olly

[Feral Rabbit]

I'm not experienced by any means,and I certainly bow to Olly's vastly superior knowledge but lots of people use the AVX mount for AP and visual and are happy with it.

LINKY

Lots of people use an 8" SCT for AP too. I'm not saying it'll be the easiest to do AP with but then again I've found a lot in astronomy to be a challenge....That's what makes it fun and my 8" SCT is great for viewing planets and some DSO's when the weather wants to play ball. If you get the Edge HD 8" and you intend to go down the AP route I suggest you get the 0.7 reducer.

The first of a set of 4 nice helpful video clips on the Edge HD 8" and AVX used for AP

I found that no astronomy equipment is suitable for all the things you'll probably want it to do. That doesn't mean you can't do what you want it to do. It just means you have to accept there will be compromises.

Regards

[Jokehoba]

I had a similar dilemma a few years back - set to buy an HEQ5 and a 100mm refractor, but succumbed to a Meade deal on the LX80 with 8" SCT. Turned out to be a frustrating beast, no good for AP and a costly mistake. Within 9 months I'd bought a secondhand NEQ6 and have loved it. It just worked the first night out with it.

The SCT will be fine for planetary imaging but a challenge for many DSOs.  A focal reducer certainly helps but images may still disappoint for the reasons Olly mentions.

You don't mention auto-guiding (unless included in 'the necessary accessories'), which will be a imperative for DSO imaging, especially with an 8" SCT.

I chose the NEQ6 because I wanted to use EQMOD, was happy to have a PC in the mix, and many people use one succcessfully for AP. I don't know much about Celestron mounts but I have heard some have issues when powered off the mains...and I power everything off AC.

The NEQ6 has been around for a long time - and could well be discontinued in the near future - but it is tried and tested.

John

[souls33k3r]

Thank you all for giving your valuable input around this topic.

May I ask, why would it be difficult to do AP of the DSOs with this AVX mount? I currently have a nikon d3100 dslr, will go ahead and buy the autoguider in the next few months time when I dive in to DSO photography.

I wouldn't want to end up with a cheap-ok-to-do mount for AP and neither do I want to be in a position where I might start asking the all so important question "Can I be asked to pick up all that (weight issues) and go out and set it up?"

Olly mate im sure you're absolutely right but truth be told i have no idea what you said there I love numbers, but in terms of this hobby I have no idea what you mean I will better understand it in layman terms

[souls33k3r]

I'm hoping I'll finalise my decision on the mount in the next few hours because the longer I take, the more my head is hurting and I've literally changed my mind on everything so many times so would appreciate that if someone can answer the above for me please

[souls33k3r]

I guess paying a little extra more now (£450) will at least save me the grief if I am to do longer exposures in the next few months or even a year or so.

Time to bump up the budget

[PeterCPC]

I do DSO imaging with my AVX but using either an ED80 or ED120 - I can get 10mins exposures ok. I only use my SCT (so far) for planetary imaging.

Peter

[souls33k3r]

Peter, mind sharing some of your work with me to see what can I achieve with AVX mount? Also would you mind telling me the gear that you use with your AVX and ED80?

I have until Monday morning to decide and then I'm going for it.

Cheers mate

[PeterCPC]

Well how about this image of the Rosette Nebula - taken with the ED80 on the AVX. Guided using a 50mm Orion Guidescope with QHY5 camera. Imaging camera was Canon 1200d (modded).

Should give you some idea at least. I'm still aquiring processing skills so it could probably be improved. You could also look on Astrobin and search for PeterCPC.

Peter

[ollypenrice]

Olly mate im sure you're absolutely right but truth be told i have no idea what you said there I love numbers, but in terms of this hobby I have no idea what you mean I will better understand it in layman terms

OK, in layman's terms 'resolution' boils down to the ability to distinguish between two very close points (eg car headlights seen at a distance.) In DS imaging you can increase resolution in principle by increasing focal length and/or using smaller pixels.

The separation of the car headlights can be measured as an angle in seconds of arc. Arcseconds. If the scope can just about split the car headlights the next question is can the camera do so? If it has huge pixels both headlights might be focussed onto the same pixel and it couldn't. If it had small enough pixels then some would have one headlight on them and some the other and you would now be resolving the lights in the image.

This issue is measured in arcseconds per pixel and it's worth spending a moment getting this clear in your mind because it is an absolutely key concept. How many arcseconds of sky land on one of your pixels?

Then reality rears its ugly head. The turbulence of the atmosphere wobbles the light beams coming in from space and means that what would be resolved above the atmosphere will not be resolved below it. The seeing limits the arcseconds per pixel which can be resolved. The precise value of what can be resoved varies from nght to night and within one night.

What is more, every mount has a limit to its accuracy and the errors within the mount will smear out the finest details.

So that brings us to the list I posted earlier.

Less than 0.5"P/P. Nuts. I wouldn't do it.

0.5 to 1.0. Premium mount and good seeing - just about worth a go. Permanent setup vastly to be preferred.

1.0 to 1.5. Difficult-ish but nice if you can make it work.

1.5 to 2.5. The sweet spot with low pain and decent resolution.

2.5 to 3.5. Worth doing if you are going to get a cracking field of view out of it.

 

You can put a DSLR in an 8 inch SCT and have a theoretical resolution of 0.4 arcsecs per pixel or whatever, but you simply will not acheive that. You'll get a picture but you would get the same level of detail, plus a wider field of view, if you used a shorter focal length scope.

 

Olly

 

PS The values in the list are just approximations and all of us will have our 'guesstimates' but I'd be surprised in there were radical disagreement here.

[gnomus]

My advice is to listen carefully to what Olly is saying and if you don't understand it then read up on it before spending your hard-earned.  About a year ago I did almost exactly the same as you - I bought a CGEM and Edge HD 8" package.  It is absolutely fabulous for visual work and for imaging the moon and planets.  From the outset, I had hoped that I could use it for long-exposure DSO imaging.  I had been advised (by Olly and others) that this might prove challenging, but I found chaps on the internet who seemed to be getting OK, even good, results.  I have no doubt that good results can be achieved by people who know exactly what they are doing, can diagnose problems when things go wrong, and who have the ability to tweak their hardware and software to sort out these problems.  This is a very steep learning curve, however, and I had no such abilities (and still have lots to learn).

My advice would be - decide what you want to do.  If you want high magnification views and are happy to image solar system stuff then get the AVX and a SCT.  This is probably the 'easiest' way forward.  Do you need to pay for 'Edge' optics if you are only doing visual and lunar/planetary imaging, though?.  If you really want to get into DSO work then do not try to do this with a heavy 2032mm focal length scope.  Instead get a decent mount and a cheapish refractor like the ubiquitous ED80 as used by PeteCPC in his lovely image of the Rosette Nebula.  Then get guiding as soon as you can.  You will save yourself lots of frustration and many wasted nights (which are few enough around these parts).

I got on OK with my CGEM mount but many many more people are using one of the SkyWatchers and, as such, when you need help you may find that more easy to come by. 

Good luck.

[souls33k3r]

PeterCPC my God!!! That is such a gorgeous image and that's exactly what I would like to achieve for the money that I'd like to spend. Thank you so much for sharing and I'll most definitely be looking at your other work on Astrobin.

Olly, you're a legend mate A LEGEND!!! I'll surely spend more time reading up on that and tha ka once again for taking our time and explaining this in layman's terms

Gnomus, Edge optics will most definitely be used to do visuals and imaging of the Solar system, perfect my techniques and then like everyone has been suggesting, will go for an Ed80 frac later... DSO imaging is where I'd sure be ending up but first things first, spend money wisely on the mount and OTAs come later.

Seems like NEQ6 Pro seems to be the best and wise choice to spend money on which will save me a lot of frustrations going forward.

Sky is the limit with this hobby and I knew from the word Go that this isn't going to be cheap and lots and lots of learning curve involved and am much more happy to do so too.

This forum has certainly proven to be quite resourceful and good folks like you always available to give guidance

[MartinFransson]

Listen to the experienced imagers! I didn't [emoji16] I thought a real mount was too expensive so I got an AstroTrac. After a year I had to get an HEQ5 since I grew out of the AstroTrac. Sure, if it had been even remotely doable I would have bought a NEQ6 or better but no money, no play.

Second, do as suggested and start off with more modest focal lengths! When you get the hang of that, move on. I am just trying to move on myself, but here's what I did with the AstroTrac and a 300mm tele lens + cheap DSLR.

*Edit* - attached larger format image instead...

[souls33k3r]

Cheers for sharing your experience Martin. I guess I've made up my mind now and will go with NEQ6 PRO mount and EdgeHD 8 OTA and then get a focal reducer to begin with.

You guys have been nothing short of awesome. A great help. You can be sure I'll be back asking a lot more questions

[souls33k3r]

Right, so given the green light to guys at WSC on the NEQ6 Pro and EdgeHD 8" scope, hopefully if all goes well, i'll be playing with my kit on Saturday evening It does say the day is poor for stargazing but lets see if i am lucky enough to a bit of visuals.

Thank you once again for everyone on helping me out here