Eq3Pro vs Heq5

[mikey2000]

Hi all,

 

In looking to make the next step in my imaging, I think I may need to upgrade my mount.

I would greatly miss the EQ3 DSO Challenge thread (and may even feeling like  I am “selling out” a little)

 

it it seems the obvious upgrade is from Eq3 Pro to Heq5

 

I can guide my eq3pro with my 130mm/f4.5 guidesxope and qhy5L-I guide scope.  It’s ok but there is an annoying 19 second period 2-3 arcsec wobble that can’t be corrected by PEC and more worryingly, occasional large DEC jumps/slips that I am quite sure are cause by me using the mount at the very limit of its specification

 

 

i wonder if any members could chime in here, especially if they have made this kind of upgrade themselves.

 

Is the guiding accuracy better? (I’m thinking I could buy a bigger/better guidescope for the new mount with upgraded weight limits)

does the HEQ5 suffer DEC glitched?  I have become “ok”’at setting up unidirectional guiding on my eq3.  I wonder about the backlash on a better mount

 

footprint: my entire rig (eq3, 150pds)?is easily lifted but is a little awkward to manoeuvre through a few doors into the garden.   Is the heq5 tripod much wider on the ground?  I know it is heavier but I can’t help wondering if i can move the whole strip without dismantling too much.

 

thanks again!

[Stub Mandrel]

It's an interesting issue.

I do wonder about the added convenience of a HEQ5 over my home-built setup, plus having the ability to dither and potentially solving the DEC issue.

I found a heftier stepper, some roller thrust bearings and a nose-heavy arrangement gives me decent DEC performance - except when pointed straight up and it starts to over-balance!

But I much as I want to champion the EQ3-2 (the one I have) this is more about stomping the myth that  people who have one or can only afford one shouldn't attempt astro photography, rather than claiming it's the ideal solution.

An EQ5 or HEQ5 is probably on my horizon in the longer term.

 

[bobro]

Well, my upgrade was from a (guided EQ2) to a CG5 (EQ5), mainly to have GOTO facility. For sure the CG5 produced tighter stars in the RA plane but, a big surprise to me, was the poorer performance in the DEC plane. The EQ2 has a paddle to control DEC direction, whereas the CG5 a worm gear. The EQ2 doesn't suffer from DEC backlash, but I continue to struggle with DEC backlash on the CG5.

To carry the CG5 outside I remove the counterweight, a slight annoyance.

In a bid to improve dithering (easy to dither with the EQ2 but I couldn't get DEC dithering to work on the CG5) and guiding accuracy, I converted the CG5 from regular SkyWatcher stepper motors to belt driven stepper motors using AstroEQ to drive them. That made a good improvement (30-40% perhaps) and allowed DEC dithering to work (just!).

Of course GOTO is great and the CG5 produces better images (when DEC behaves), but the upgrade path isn't always what might be expected. Now with a bit more experience under my belt I'm becoming more and more inclined to get the EQ2 out and see what I can make it do on an easy to find target. Watch out EQ3 thread, I might post something again...

Good luck nevertheless!

Bob

[happy-kat]

Is the biggest challenge to your eq3-2 the size and weight of the 150pds. If you use say a camera and lens do you still get the dec jumps? Or even just set it tracking more or less empty does it still jump. I guess it's how much is the budget to see change and what caveats protect the change to ensure the value and use to you.

Edit: I don't have a real eq mount just an avid follower.

[Stub Mandrel]

Here's a thought for the EQ3 DIY obsessive like me.

Use the usual system for GOTO, but have a leadscrew and an arm fitted for adjusting DEC.

[mikey2000]

22 hours ago, happy-kat said:

Is the biggest challenge to your eq3-2 the size and weight of the 150pds. If you use say a camera and lens do you still get the dec jumps? Or even just set it tracking more or less empty does it still jump. I guess it's how much is the budget to see change and what caveats protect the change to ensure the value and use to you.

Edit: I don't have a real eq mount just an avid follower.

I think I'm definitely on the very weight limit.    I found the recommended spec once and weighed my kit.  It was just over the 'observation' weight limit.  But only just.  

 

The DEC jumps don't always always happen.  I think it's when I get the balance wrong.  There's a lot of backlash in the DEC motor/worm setup so I detune the polar alignment to get one-way drift and so unidirectional guiding.  I think I get the DEC jumps when I'm effectively using DEC guiding to lower the nose of the scope.  It's all well until it just slips a bit and gravity takes over - the jump is always the same direction.   It's a bit like balancing RA to be east heavy but with DEC and drift, I find it rather hard to get my head around, so I opt for pot luck.  Some nights I win, some I lose.

 

Also there is a moderate short period error from the RA drive.  It doesn't divide exactly into the worm period so PE Correction won't help it.   So, I guide it out.  This means I need to use very short guide exposures and can end up chasing the seeing a little bit.   

 

My EQ3 is an OK setup, just not a great one.   I have a feeling that with more stable mounts, I'll spend a lot less time setting up and more time actually imaging...