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M31 Andromeda


Stardust1

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One of my favorite deep sky objects in the night sky, the great Andromeda galaxy.

All the processing has been done with Pixinsight. The scope was FSQ-85 with the good old unmodded Canon 6D. Around 5 hours of data with 5 minutes exposure.

Hope to add some short exposures to the core someday.

integration_FINAL_PROCCESSED.jpg

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1 hour ago, Stardust1 said:

One of my favorite deep sky objects in the night sky, the great Andromeda galaxy.

All the processing has been done with Pixinsight. The scope was FSQ-85 with the good old unmodded Canon 6D. Around 5 hours of data with 5 minutes exposure.

Hope to add some short exposures to the core someday.

integration_FINAL_PROCCESSED.jpg

Excellent image of M31....Your image of M31 is certainly astronomy magazine material!

I've often wondered what size of scope would it take to image some of M31's star clusters? Obviously the Hubble can do quite easily, but what about an Earth-based telescope? >

https://upload.wikimedia.org/wikipedia/commons/c/c4/Star_cluster_in_the_Andromeda_galaxy.jpg

Klitwo

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1 hour ago, fireballxl5 said:

lovely image! 

Is this with a standard FSQ85? No additional flattener?

I need to try this target with my (same) set-up. 

Thank you! Yes, the image was taken with the standard FSQ85, without flattener.

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Excellent image.

16 hours ago, Stardust1 said:

Hope to add some short exposures to the core someday.

You may not need to. Is the core blown out in the individual subs? If it isn't, hdr processing will probably restore it quite nicely.

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That's a lovely image! I've tried to capture M31 twice now and the results are poor! Turning into my nemesis I think!

 

Sorry to pixel peep but I'm curious as to what the artefacts on your bright stars are? They appear to run parallel to the centre of the image. I'm sure I've seen the same artefacts on another Tak image. I get 3 similar bright star 'spikes' on my WO but the orientation doesn't change. I understand it's to do with how the lens cell retains the glass but that doesn't explain the Tak spikes!

Screenshot_20190127-101451_Firefox.jpg

Screenshot_20190127-101529_Firefox.jpg

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6 minutes ago, david_taurus83 said:

Sorry to pixel peep but I'm curious as to what the artefacts on your bright stars are?

That's diffraction. It means that something is interfering with the light as it goes through the scope. Lens and mirror clips are the most common causes.

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Just now, wimvb said:

Those are diffractions. It means that something is interfering with the light as it gies through the scope. Lens and mirror clips are the most common causes.

That's what I thought but why do they change orientation? The bright one above is on the left of the image so it runs top to bottom. But the not so bright on is running diagonally. Should it not be the same like Newtonian spikes?

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26 minutes ago, david_taurus83 said:

That's what I thought but why do they change orientation? The bright one above is on the left of the image so it runs top to bottom. But the not so bright on is running diagonally. Should it not be the same like Newtonian spikes?

Excellent point. I have no simple answer to this. The pattern changes orientation around the image, similar to a flattener spacing problem. Perhaps we're seeing a combination of diffraction and spacing.

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8 hours ago, wimvb said:

Excellent point. I have no simple answer to this. The pattern changes orientation around the image, similar to a flattener spacing problem. Perhaps we're seeing a combination of diffraction and spacing.

This is a well known Tak effect and has affected the FSQ85 and pair of FSQ106Ns that I've used extensively. Greg Parker suggested slightly pinched optics. I don't think it has anything to do with lens clips. Compared with the stellar artefacts thrown up by such instruments as the Hubble I can honestly say that it hardly matters. ps54_5x7.png

I'm not knocking the Hubble image, I'm asking who cares about the stellar atrefacts when looking at this? Not I.

I think Stardust1 has a cracking Andromeda there, maybe just a little colour cold to my eye. I'd be inclined to warm it up a bit if it were mine but it isn't mine! 

I've spent quite a while messing about with the core on this target and short subs don't provide an easy fix. I found that utter brutality was the only way to drag the hints of spiral structure further into the core. I'm glad nobody was watching when I did it!

?lly

Edit: the FSQ scopes are flatfield Petzvals so they need neither flattener nor spacing unless the reducer is used. The reducer is not a flattener but does need correct spacing. WIthout it all you do is focus. Why do I like them???

 

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Yes, a very good M31.  Good focus and framing.

Like Olly I think the image would benefit from 'warming' the overall palette - the whole frame has an overall blue feel, perhaps due to the quite white core which has a warmer yellow tone.

These would be my suggestions for constructive feedback in an excellent M31 ?.

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Excellent image, excellent job.  

My only comment is that the sky background is rather dark and I wonder whether there is yet more galaxy nebulosity to be shown in the outer regions in a slightly less dark background.  

Carole 

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Regarding the spikes that some of you have mentioned, it seems that some other optics do show this artifact as well. Here is an example of a Samyang 135mm F2 lens:

https://www.cloudynights.com/topic/547028-anyone-know-what-causes-this-artifact-on-bright-stars/

According to "Jerry Lodriguss", see above link, post#5, these artifacts are caused from aperture vignetting. It seems that the edge of the field doesn't see the full circle of the aperture. On post#13 of the above link you can see the simulation of the "almond" shaped aperture on star shape.

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