M44 - Beehive Cluster

[Robert Chandler]

Good Evening All,

 

This is my attempt at M44, aka the Beehive Cluster, my first time at anything other than a galaxy or nebulae.

Captured on the Skywatcher Evostar 120ED. I was using the ASI1600MM camera and shot through the Luminance Filter, was this a correct choice?

I am still trying to work out which filter to use, I haven’t even touched the Red, Green or Blue Filter yet.

 

I think that the issue with the slightly elongated stars, which you have identified is down to one (or a combination) of these factors

 

1. The tripod was set up on grass and I noticed this morning when packing it away because of the potential weather we are expecting that the legs had sunk down,
2. The counterweight balance had moved slightly from where I had marked them; and
3. My setup is close to a road and I felt some vibration when a large lorry had passed by.

 

My solution is that I will in due course is locate the tripod legs onto a firmer surface, in due course if the management permits some small paving slabs, tighten up the weights and finally some anti-vibration pads for the tripod legs arrived today (thank you Amazon).

Have I missed anything at all?

 

Bob

[Trev S]

Hi Bob,

I find that star clusters are best with R, G and B images combined to give the stars colour.  From memory, most of the stars in M44 are bluish and background stars are various from blue to red.  Alternatively, you could use a single shot colour camera if you have one.

Three bricks or paving slabs sunk into the grass should provide a nice firm base and grass is good at soaking up external vibrations too.  I would suggest that once you find the best alignment for your scope and tripod, mark the positions of the tripod feet so you can replace it in the same position later.  I find that saves me considerable time setting up.

Do you use a guide scope or just rely on the mount tracking accuracy? Even the most accurate alignment will probably show elongated stars after a minute or so and a less accurate alignment after just seconds.  A combination of level tripod, accurate polar alignment and good guiding should eliminate the elongated stars.

Hope this helps.

[Robert Chandler]

Hi Trev,

Your suggestion about the brick / paving slabs is the ultimate intention but I have to convince the boss to let me do anything in her garden.

Yes I was guiding and from memory the average RMS was about 0.8 which I think is good. I was using the skywatcher 50mm ED as a guidescope attached to a ASI1600MM mini camera. All plugged into the ASIair Pro. I was using a HEQ5 Pro mount.

On the app clearoutside it is showing some green on Thursday night so will try RGB filters. I will also  try the RASA8 with the ASI294MC OSC.

Bob

 

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[tcos...@gmail.com]

Hi Bob

A nice image of the Beehive you have taken there. Open star clusters make good targets as they don’t require long exposures to get good results. The description of the issues you are trying to tackle brings back memories of my own first steps in astro-photography about 10 years ago. I agree with all of Trev’s suggestions regarding setup and use of filters and would encourage you to continue with your imaging as it does become easier with practice!

Cheers

Tim C

 

From: croydo...@googlegroups.com <croydo...@googlegroups.com> On Behalf Of Trev S
Sent: 09 March 2021 22:30
To: croydonastro <croydo...@googlegroups.com>
Subject: [croydonastro - 6846] Re: M44 - Beehive Cluster

 

Hi Bob,

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[Robert Chandler]

Thank you Tim. Just need the weather to improve  with clearoutside saying maybe a few hours on Thursday and again on Saturday

Bob

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From: croydo...@googlegroups.com <croydo...@googlegroups.com> on behalf of tcos...@gmail.com <tcos...@gmail.com>
Sent: Wednesday, March 10, 2021 7:45:03 AM
To: croydo...@googlegroups.com <croydo...@googlegroups.com>
Subject: RE: [croydonastro - 6847] Re: M44 - Beehive Cluster

 

To view this discussion on the web visit https://groups.google.com/d/msgid/croydonastro/2f0d01d71581%244873ebc0%24d95bc340%24%40gmail.com.

[trevsie7]

Another thing I found can cause elongated stars, is balance on Ra and Dec axes.  The balance should be slightly heavier towards the east and down so that it doesn't bounce around on the backlash, though this would show up on the guiding graph if it was bad enough.