Hem 27 EC or not ?

[Robneq6]

Hi I am looking at the hem 27 and possibly the hem 27 ec

i would be using an ASIAIR pro and autoguiding  and wonder if this would negate the benefits of hem 27 ec

please could anyone  let me know their thoughts and opinions on this and help me get a better understanding so as to make a more informed decision 

many thanks  
regards  Rob

[Elp]

The EC is for more accurate guiding when you're not using a computer controller due to the included encoders As far as I know you won't gain anything if autoguiding an EC mount and will be paying more for it, I could be wrong.

[Robneq6]

10 minutes ago, Elp said:

The EC is for more accurate guiding when you're not using a computer controller due to the included encoders As far as I know you won't gain anything if autoguiding an EC mount and will be paying more for it, I could be wrong.

 

[Robneq6]

I was not sure if that would be the case 

that’s why I put the question out there to see what other people think 

thanks

[Elp]

This thread might help you:

https://www.cloudynights.com/topic/823200-are-high-precision-encoders-essential-in-harmonic-drive-mounts/

 

[Adam J]

2 hours ago, Robneq6 said:

Hi I am looking at the hem 27 and possibly the hem 27 ec

i would be using an ASIAIR pro and autoguiding  and wonder if this would negate the benefits of hem 27 ec

please could anyone  let me know their thoughts and opinions on this and help me get a better understanding so as to make a more informed decision 

many thanks  
regards  Rob

if you are autoguiding don't get the EC version, I have heard some say that the EC can actually end up in a fight with the guiding, not sure on how true it is. But if you are guiding on short exposures ~1second an EC will add very little to the accuracy. Just something else to go wrong. 

Adam

Edited January 12 by Adam J

[fwm891]

I’m using an ASIAIR Plus and have an HEM 27 on order. I went for the standard 27 because I intend using it via the air plus. I’d read about conflicts between the EC and PC controllers of the mount so decided to save some money. The airplus’s PA is said to be better than the iPolar too.

[Robneq6]

Ok thanks for your replies will be looking at hem  27  plus autoguiding

[fwm891]

My HEM27 has now arrived. It works well with my ASIAIR Plus or with my laptop and NINA. Just a quick test run at present but no real snags to contend with. I just have to remember it uses a different commander software to my CEM60.

[fwm891]

Tried the HEM27 out last night: Full Moon, no filters, IC434 (Horsie) not the best subject with no filters under a full moon! Mount control via ASIAIR Plus. RASA 8 mounted with an ASI 585MC camera fitted, guiding with a 9x 50 guide scope. PA taken into AIR+'s the smallest circle ? then straight to IC434 centred on the chip with minor framing alteration. Focus adjusted and 20x 30 second 'Live' frames stacked.

I moved on to M45, then M42 and a couple of other targets moving each side of the meridien framing on chip each time with minor adjustments.

Pleased with this first test of the mount under stars (shame about old blobby). Although it didn't actually perform a flip on the same target I did take it each side and it found what it was asked for.

As a precaution I kept the max slew rate down a notch at x512 as I 'm tripod mounted but it all handled well so next time out I'll change the settings and let it slew at max.

IC434 image attached. Colours are a bit washed out from the full moon. Processed in PI.

 

[Robneq6]

Hi Glad to see that everything looks ok with your hem 27 image looks good considering the circumstances at time of capture.

i to have a cem60 and also a rasa 11 but i am finding it increasingly difficult to get the gear set up so am looking at scaling things down so I was interested to see what your views are about the hem27 and it’s abilities.

[fwm891]

7 hours ago, Robneq6 said:

Hi Glad to see that everything looks ok with your hem 27 image looks good considering the circumstances at time of capture.

i to have a cem60 and also a rasa 11 but i am finding it increasingly difficult to get the gear set up so am looking at scaling things down so I was interested to see what your views are about the hem27 and it’s abilities.

The 8 inch RASA is probably the largest kit I’ll use tripod based with the ‘27, at least that’s my thinking at the moment. I need to get a short losmandy plate to mount my 80mm f6 refractor on which will probably be the main grab-n-go set-up. I don’t want to get involved with counterweights, the RASA set-up is easy to Dec balance as the guide scope/air+ assembly is on a lockable slide on the RASA’s top rail. If I have the 585 mounted I can slide the assembly forward compared to when I have the 2600 Duo mounted on the RASA. 

So at present I’m getting a new routine sorted for setup. once I have all the bits in place and stored together as ‘a kit’ things will go much quicker. Spent a good deal of time taking cables from different kits for the test run. As the ASIAIR Plus is the common factor I’ll keep all the cables with the air regardless of which scope/camera option I decide to use. Hopefully then the muttering will become a little less frequent…