To nebula or not to nebula.

[Jm1973]

Hi fellow stargazers! First of all apologies for the long-winded diatribe, but here goes:

Yesterday my copy of Turn Left at Orion finally arrived. I'd been having problems with my polar and 3-star alignments, and my Goto mount wasn't 'going to' where it's supposed to, so I thought I'd have a quick look at the book and try my hand at manually navigating the stars. I flicked through the pages till I saw a nebula in the Summer months section, which used Vega as a starting point. As I'd used Vega for my 3-star alignment earlier that evening and knew where to find it, I decided to try to find the Ring nebula in Lyra.

The instructions in the book said to first find the Summer Triangle. Well I'd never noticed it before (goes to show how unobservant people can be) but as soon as I looked I couldn't miss it. Then I had to look midway between Vega and Albireo, to find two faint stars Sulafat and Sheliak. Again, after staring for a while I could see those with the naked eye. Then I had to look for a star in between those two, slightly nearer to Sulafat. There was no way I could see that with the naked eye so I had a look with the viewfinder. 

I got close to where I thought it would be through the viewfinder, then looked through a 25mm EP. At first I got confused with the scale and thought I was much further zoomed in than I actually was. So I spent a good ten minutes trying and failing to find my bearings. Then I realised that I was essentially at the same scale through the EP as through the viewfinder. So I just visually tracked from Vega to Sulafat. At this point I could see Sulafat, Sheliak and Burnham 648. So then I looked in the middle of Sheliak and 648 but couldn't see anything resembling a nebula.

So I attached my Nikon D3300 (not the best for AP but hey ho) directly to the telescope (200P Skywatcher) and took a ten second exposure. All I could see were large what looked like raindrops. So I started the laborious task of focusing a tiny amount and taking another picture. After about 15 or 20 pictures I was more or less in focus. So then started tracking about methodically looking for the ring nebula.

After about 3 or 4 exposures I could see a bright object on the edge of the photo. Aha! I thought... this must be it. But as I got it fully into the photo I could see it was just a star. So I figured this must be Sulafat and I kept heading towards where I thought 648 might be, taking photos every few seconds. After a long time I didn't see another star of a similar brightness, so I thought I must be going in the wrong direction. I Went back till I found the bright star and tried again in the opposite direction. Couldn't find anything there either. At this point the clouds were coming out, so I took a bunch of photos of the bright 'star' I'd found, as this was the only thing that looked even slightly noteworthy among the photos I'd taken. Then I took everything down and went inside. 

Afterwards, I had a quick read of the page about the ring nebula and was struck by the sentence that said, 'there should be no trouble seeing it in a telescope.... in your lowest power it may be hard to distinguish from a star at first.' Then I remembered reading somewhere that stars look lik epoints of light, and when you zoom in on a star it will still look like a point of light. This thing did not look like a point of light.

So to not quite cut a long story short, I think I may have actually got some pics of the ring nebula, after all. It didn't look as I expected it to, but that may just be due to the diffraction spikes and the fact I was just using my camera and the telescope without any additional magnification. So can anyone confirm what I have photographed please?
 

[alacant]

55 minutes ago, Jm1973 said:

can anyone confirm

Hi

The bright star is Vega. Alas, no ring nebula:(

[Jm1973]

3 minutes ago, alacant said:

Hi

The bright star is Vega. Alas, no ring nebula:(

Ah, right. I was way off then. Thanks for confirming.

It seems to me that if Vega looks that size then I am unlikely to be able to see M57 with just my camera attached to the telescope.

Does that sound correct to you?

[alacant]

8 minutes ago, Jm1973 said:

I am unlikely to be able to see M57

No, but get the nebula in the field of view and stretch the image, you'll then see it.

Cheers

[Jm1973]

I see. That's useful information, thanks. I have got Darktable installed, but I am not at all familiar with it.

So I need to be looking about here then, I guess. So not that far away really. I'll have another go tonight.

 

 

In fact I might already have a shot where it is in view.

How do I go about stretching it in darktable?

Edited September 15, 2020 by Jm1973

[rob_r]

Hi. I have seen M57 and photographed with a Canon 600D it under Bortle 6 skies with a Skywatcher 127 with a 25mm EP. It is extremely faint and small, like a hazy high cloud. It is best when I use 'averted vision' to see it. It is surprisingly bright when I do this, almost like a vibrant blue. Hope you find it, it is a worthy target. It is the within the area marked with the blue square.  

Edited September 15, 2020 by rob_r

[Jm1973]

1 hour ago, rob_r said:

Hi. I have seen M57 and photographed with a Canon 600D it under Bortle 6 skies with a Skywatcher 127 with a 25mm EP. It is extremely faint and small, like a hazy high cloud. It is best when I use 'averted vision' to see it. It is surprisingly bright when I do this, almost like a vibrant blue. Hope you find it, it is a worthy target.

Ah.. so I was in between the wrong two stars. I will definitely try again tonight weather permitting.

Edited September 15, 2020 by Jm1973

[Seelive]

This is a photo of Lyra taken last year with a 100mm lens. If you zoom in, M57 is the 'green' star between the bottom 2 stars of Lyra.

https://britastro.org/node/18742

Edited September 15, 2020 by Seelive

[Chefgage]

Just to let you know I have observed the ring nebula a few times in my 200p. Quite noticeable even in my bortle 8 ish skies.

[Jm1973]

1 hour ago, Seelive said:

This is a photo of Lyra taken last year with a 100mm lens. If you zoom in, M57 is the 'green' star between the bottom 2 stars of Lyra.

https://britastro.org/node/18742

Sorry, I've no idea where I'm supposed to be looking. I assume the birghter star is Vega.

[Jm1973]

32 minutes ago, Chefgage said:

Just to let you know I have observed the ring nebula a few times in my 200p. Quite noticeable even in my bortle 8 ish skies.

What size EP were you using when you saw it, please?

[Chefgage]

45 minutes ago, Jm1973 said:

What size EP were you using when you saw it, please?

Good question it was a while ago. I will have used my BST 18mm to first locate it and then used my BST 8mm to observe it (I have found it before with the 25mm that came with the scope and then swopping that for a higher power one, again with what came with the scope).

He way I would find it is as follows. Using the BST 18mm I would get the star Sheliak in the field as view to the extreme right as shown below.  I would then centre the ring nebula and then swop out the eyepiece for the BST 8mm one as shown below.

The first image shows the 18mm eyepiece and the second image is the 8mm eyepiece.

Edited September 15, 2020 by Chefgage

[Seelive]

58 minutes ago, Jm1973 said:

Sorry, I've no idea where I'm supposed to be looking. I assume the birghter star is Vega.

Yes, the bright one is Vega.  Here's an annotated version:

[Jm1973]

22 minutes ago, Chefgage said:

Good question it was a while ago. I will have used my BST 18mm to first locate it and then used my BST 8mm to observe it (I have found it before with the 25mm that came with the scope and then swopping that for a higher power one, again with what came with the scope).

He way I would find it is as follows. Using the BST 18mm I would get the star Sheliak in the field as view to the extreme right as shown below.  I would then centre the ring nebula and then swop out the eyepiece for the BST 8mm one as shown below.

The first image shows the 18mm eyepiece and the second image is the 8mm eyepiece.

 

Oh wow. That shows up quite well. I've got a 10mm EP or a 6mm. 

They aren't particularly expensive ones, but hopefully good enough to make it out visually.

I'm not sure how well it will get picked up by my Nikon though, unless I try putting a EP between the camera and the telescope.

[Jm1973]

10 minutes ago, Seelive said:

Yes, the bright one is Vega.  Here's an annotated version:

Ah, that makes more sense. I'm finding it difficult to spot the constellation stars amongst all the others.

I expect I will get better with practise. 

M57 looks closer to the centre os Sheliak and Sulafat than I thought.

[Erling G-P]

With regards to focusing, you should simply use live view & a bright star.  Center it and zoom in as far as possible.  If you use a Bahtinov mask, it becomes really easy.

I have tried imaging M57 with my SW 200PDS & a Nikon D7000, so a setup very similar to yours.  It's a tiny target, so I have experimented with a 2x Barlow, but unguided I had to toss many subs, even at only 15 secs, due to tracking errors also being amplified 2x, and my HEQ5 Pro mount is on the small side for a 200PDS.

I'm attaching my less than stellar image, just to give you an idea.  There's some aligning problems with the right border that I haven't bothered cropping out.  If you image without a 2x Barlow, the nebula should be half the size it is in my image.

Edited September 15, 2020 by Erling G-P

[ollypenrice]

The term 'magnification' isn't used in astrophotography and with good reason. It is literally meaningless. What is being magnified? Certainly not the Ring Nebula because that is quite a bit bigger than any picture of it ever created! We say something is magnified 100x when an eyepiece magnifies an image on our retina by 100x. That makes sense.  A scope/camera doesn't produce an image on our retina so what are we magnifying? Nothing. We're not. So what are we doing?

We are using a telescope to project an image onto a camera chip. The longer the focal length of the telescope, the larger that projected image will be. But -and this is very important- how many pixels do we put under that projected image? The more the pixels (i.e. the smaller the pixels) the larger the final image will be. The useful and meaningful unit here is arcseconds per pixel.  How much sky lands on each pixel? The smaller the amount of sky per pixel, the larger the final image will be.

This is the closest we can get to talking about 'magnification' in astrophotography. It is worth getting your head around this because, until you do, you'll be confused.

Olly

[Marvin Jenkins]

I know Astro can get confusing and very frustrating especially when trying to get a Goto mount working just how you want it.

Firstly I have to say with all respect to replies to your original op, you seem to be trying to find the Ring Neb via an EP. This is doable with a 200p just takes some practice and a little knowledge of that bit of sky.

You are doing nothing wrong. Just take your time and don’t complicate anything. If you cannot find an object in the EP then adding cameras is probably going to add questions. If you find it, then definitely add a camera.

Try finding something like M13 a large bright glob in Hercules. See it in your finder scope first, compare it’s position to stars in the square of Hercules. A large target like that is the way to learn an object in relation to its surrounding star field.

Planetary nebula are bright so seem a great choice, but they are so small they are very hard to to find. I have had nights when I know the Goto is perfect but I have had ten minutes at the EP to realise that the center object in the fov is not just another star, but the ‘target pn’ !

Happy hunting and clear skies. Marv

[alacant]

34 minutes ago, Marvin Jenkins said:

trying to find the Ring Neb via an EP.

Ah, ok. I thought that as the op posted in the imaging forum and asked a question about an image he'd posted, it was about imaging. 

I fully agree that it's much easier to take the camera out of the equation and simply scan for the the nebula using an eyepiece.

I apologize for leading the post astray.

Cheers

Edited September 16, 2020 by alacant

[Marvin Jenkins]

9 hours ago, alacant said:

Ah, ok. I thought that as the op posted in the imaging forum and asked a question about an image he'd posted, it was about imaging. 

I fully agree that it's much easier to take the camera out of the equation and simply scan for the the nebula using an eyepiece.

I apologize for leading the post astray.

Cheers

I completely understand, EP leading to Camera is normally what happens (did with me) but jm1973 needs to find the target first to photograph it. Also it was quite an in-depth post so it covered a fair amount.👍

Marv