M81 30 hours

[HunterHarling]

This is a work in progress, at least as far as processing goes. This is only RGB, as I ran out of time to get L. 🙄 Not too sure about my processing at this point, I also have collimation issues, which can be seen.😟 I need a refractor...

30 hours of 300 sec R,G, and B images.

All in all, I'm pretty happy with it, but I'm definitely going to reprocess. How can I improve?

 

Thanks for looking.

[Seanelly]

No tips, no critiques, just admiration for a job well done.

[RugbyRene]

I would be extremely happy with this. I think you're being too hard on yourself.

[Demonperformer]

Beats my best attempt.

[Brian Maurer]

Very nice, I’ve never had much luck with this target.

[Ivan Hancock]

Very nice, can't see what you mean about needing a new refractor ?

[HunterHarling]

1 hour ago, Ivan Hancock said:

Very nice, can't see what you mean about needing a new refractor ?

Thanks everyone. 

Ivan- my C8 is always needing collimation, and it gives the stars a weird half-blue half-red color...

[AltAzAstro]

Excellent image, can't help but praise and congratulate.

Do you know what is the magnitude of the small galaxy that can be barely perceived as an elongated disk on the right of M81 and a bit to the bottom?

I could not find it of any of my planetarium apps ... hence I guess it is pretty dim ... 15-16?

 

ADD-ON

By the way, I now notice there is another one, even slightly fainter on the other side of M81, almost symmetrical to the first.

Edited June 21, 2019 by AltAzAstro

[antariksha]

Outstanding work.. Image is really good. Congratulations....

[Gina]

Great image nicely processed IMO - can't see that it could be improved.  Lovely!

[souls33k3r]

Absolutely brilliant. Really love what you've done there.

Mind if i ask what gear did you use to capture this and also what are you skies like on the bortle scale?

[Adam J]

11 hours ago, HunterHarling said:

 I need a refractor...

You might get nice round stars but you may also find the galaxy will not have the same detail, your stars are not that bad anyhow...

[HunterHarling]

10 hours ago, AltAzAstro said:

Excellent image, can't help but praise and congratulate.

Do you know what is the magnitude of the small galaxy that can be barely perceived as an elongated disk on the right of M81 and a bit to the bottom?

I could not find it of any of my planetarium apps ... hence I guess it is pretty dim ... 15-16?

 

ADD-ON

By the way, I now notice there is another one, even slightly fainter on the other side of M81, almost symmetrical to the first.

I'll have to check it out. My images usually get around 16-17 mag dim, so it's probably around there.

 

8 hours ago, souls33k3r said:

Absolutely brilliant. Really love what you've done there.

Mind if i ask what gear did you use to capture this and also what are you skies like on the bortle scale?

Thanks. I used an Edge 8" SCT, ZWO asi1600mm, and Orion Atlas Pro az-eq g mount. My bortal scale is about 5 and I can see to 5.5 magnitude on a clear night.

[alan potts]

An outstanding capture and one of the best I have seen of this.

Alan

[Kev M]

15 hours ago, HunterHarling said:

 How can I improve?

 

 

Short of buying Hubble....don't think you can

That is spectacular

[tomato]

30 hrs, and it’s all in there, great M81.👍

[ollypenrice]

I think you should have more faint stuff. The background doesn't look clipped and seems to be at a reasonable level but Holmberg is struggling and there is no sign of Arp's loop. OK, the L layer is the one for finding these so why spend so long on the colour? What you have of the galaxy is very good, for sure, but do you need 10 hours per channel? I've never gone anywhere near that. You won't need 10 hours in L to take this to another level.

Olly

[HunterHarling]

20 minutes ago, ollypenrice said:

I think you should have more faint stuff. The background doesn't look clipped and seems to be at a reasonable level but Holmberg is struggling and there is no sign of Arp's loop. OK, the L layer is the one for finding these so why spend so long on the colour? What you have of the galaxy is very good, for sure, but do you need 10 hours per channel? I've never gone anywhere near that. You won't need 10 hours in L to take this to another level.

Olly

I was trying not to over stretch the image... but I do have about 10 hours of L. Would about 10 hours of L be worth it to add? I assumed that I would need 20-30 hours to make a difference.

[wimvb]

Great image.

1 hour ago, HunterHarling said:

I assumed that I would need 20-30 hours to make a difference.

Not necessarily. Just process the L to the best of your ability and blend it into the colour (lrgb combination). If you want more L, you can combine the r, g, and b masters into a synthetic luminance. Then combine that with the captured L master. It may improve the overall quality of the luminance, but I'm not concinced that you need it.

Edited June 21, 2019 by wimvb

[ollypenrice]

Your L will have about three times the signal of any individual colour layer so it should make a huge difference. In fact equal amounts of exposure in all four filters is in many ways ideal because the L won't bleach out the colour. It's possible to shoot much more L in search of the very faint but this makes processing harder. When stretching L in Curves you can get the background up to, say, 23, then pin it at that and stretch a little more above that to find the faint tidal (or IFN) loops and Holmberg.

Olly

Edited June 22, 2019 by ollypenrice

[MarsG76]

What a fantastic looking image... this is definitely something to be proud of.... if you collect some luma subs and create a luma channel, than that should take care of your obvious miss collimation visible on the stars.

 

[ollypenrice]

For data you already have, the stars can be given a dodgy 😁 cosmetic tweak if you have Photoshop. 

Choose Magic Wand, click on a star and save the following as an action with a function key shortcut:

Select-Modify-Expand . Try 5 but experiment. 

Select-Modify-Feather. Try 3 but experiment.

Filter-Blur-Radial Blur-Spin-Best. Repeat this (CtrlF).

Deselect.

Now you can 'roundify' a star by choosing it with the wand and hitting the function key. Very quick. You can make two versions of the action, one for small stars and one for large, by using greater or lesser values for Expand and Feather.

Olly

[wimvb]

There is a very simple test you can do to see how much real information there is in an image, such as your L master.

Make a copy of the image. Stretch that copy using histogram transform (pixinsight) or levels (ps) by bringing in the white point slider so far that you start showing details in the background. This will clip stars and the main galaxy, but it will reveal anything in the background. You may need to also bring in the black point, but do so without clipping. If you see the remains of dust motes, or a fixed pattern caused by your camera, you've gone too far. But you should definitely see the small satellite galaxy Holmberg IX, and maybe also Arp's loop before this.

It may be easier to see those details if you first invert the image, in which case of course, you move in the black point slider.

This test will help you once you start working on the original image. You can keep it as a reference to do side by side comparisons.

Edited June 22, 2019 by wimvb

[HunterHarling]

I'm working on the L data now... 

On 22/06/2019 at 01:07, ollypenrice said:

For data you already have, the stars can be given a dodgy 😁 cosmetic tweak if you have Photoshop. 

Choose Magic Wand, click on a star and save the following as an action with a function key shortcut:

Select-Modify-Expand . Try 5 but experiment. 

Select-Modify-Feather. Try 3 but experiment.

Filter-Blur-Radial Blur-Spin-Best. Repeat this (CtrlF).

Deselect.

Now you can 'roundify' a star by choosing it with the wand and hitting the function key. Very quick. You can make two versions of the action, one for small stars and one for large, by using greater or lesser values for Expand and Feather.

Olly

Thanks, I'll give this a try.

[HunterHarling]

I finally added the L data. I made a super luminance using all 40 hours of data. I think it looks better... there is definitely more ifn.

How does it look?