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tim.stephens
04-04-2018, 07:10 AM
Hi everyone,

Had been quite a while since I've posed an image to IIS. I've had no time between kids and poor weather to get the telescope out.

I've also been dealing with persistently poor tracking with my HEQ5 Pro mount, which for the most part I've narrowed down to the inadequate tripod and mounting strategy in my observatory. The HEQ5 Pro really isn't up to the task of carrying 12 KG of RC8 and imaging train but this has been compounded by a wobbly tripod, poor PA and an unstable support structure in my mini-observatory that was temporary until I could afford something more substantial.

I contracted a local metal fabricator here in New Plymouth (Weldable Alloys) to build me a Tri-Pier last month. It was substantially less expensive than I had imagined - only $700 for parts and labour and the owner Bo Mullin, had some great suggestions during construction (removable leg to get the pier into tight spaces, cement fill column and legs to add to the overall mass...).

What a difference the pier made - I was getting huge 2 - 3 arc sec spikes in RA giving me very elongated stars. Tracking now is less than 1 arc sec with my ED80 (average in PHD2 of 0.6) and 1 - 1.5 with the RC8 (12.5 kg telescope) which has for the most part fixed these issues. I think this is about as good as you can get with the HEQ5 Pro.

First photo is the original mounting with tripod in the observatory.
Second is the new pier with a very excited 5 yr old.

I've also attached two slightly different images of NGC 2467 - one at 480mm and the other at ~1190 mm with the same imaging setup, as below.

Widefield Skull and Crossbones
Explore Scientific ED80
~1 h each of 6nm OIII Astronomic and 12nm HA
10 min subs
Atix 428ex @ -10C
Moonlite motorized with DYI focuser
SGP for aquisition

Image 2
GSO RC8
~1h of OIII and HA
10 min subs as above.

Processing in PI.

Apologies for the poor resolution but I don't have a public site to post these images.

Hope you enjoy.

Tim

Placidus
04-04-2018, 08:12 AM
That's very respectable Tim. Stars round and tight. Well done!

It's come out so nicely, now you're all set up, you might like to add even more exposure to help with the background.

Great work diagnosing and sorting out the stability issues.


Best,
MnT

tim.stephens
04-04-2018, 08:20 AM
Thanks very much. It's been a long road the past three years to get to this point. Those round stars and dark nebula detail cost a lot of time and money!

I do have plans to capture more data and get the RC8 image over 2h each filter although it's a little challenging at the moment with the weather here. I only managed one 10 min sub before it clouded over last night. If the subs are any longer, I risk picking up a cloud which is unfortunate as I've seen some wonderful images with subs over 20 minutes that pick up the faint nebulosity. I have to work with what I have.

Forgot to add most of this data was captured near to full moon. even the 12nm HA seemed to manage well - very little background light pollution.

I'd really like to capture a galaxy between full moons. I'll come back to this next month when I can't collect RGB.

RickS
04-04-2018, 10:17 AM
Congrats on the upgrade and nice work on the images, Tim.

Ryderscope
04-04-2018, 10:30 PM
Good work Tim to bring your set up to the point where you can run off some good images. Looks like that new pier will do the trick.

willik
05-04-2018, 12:25 AM
Nice image Tim but need a bit more on exposure time to get more detail and NB colour out that is not a easy image.
Martin

tim.stephens
05-04-2018, 06:11 AM
Thanks guys, I'm going to try and image a few more hours tonight - looks to be a clear crisp night. Hopefully no more high cloud to ruin my session.

Still getting to grips on how much data is needed for OIII!

And that Pier is NOT going anywhere. It has to weight more than 70kg with all of that cement in the base and legs. It was a two man job to move it into the observatory.

I was imaging on the ED80 at 480mm and gave it a good wack with my hand at the top. No movement on PHD and no elongated stars on the image.

tim.stephens
18-04-2018, 07:22 AM
Update:

Have added over 2 hours more data to both OIII and HA over the past couple of weeks. Thanks for the suggestions - it has improved the image markedly. I think a little more time playing with PI has helped too. :)