My first nebula attempt - NGC 7000

[tompato]

I had a go at my first nebula with my 600D and an old Canon 50mm F1.4 a couple of nights ago on a Skyguider Pro (love hate relationship polar aligning this).

I did around 45 x 45s and my target went partially behind a tree which was frustrating. It was at f2.8 if I recall correctly and then a stacked, cropped and did some basic levels and tweaks in GIMP. (Edit - ISO 800)

It's not much but I'm fairly happy with an old lens and an old camera which I had laying around. I think I might be getting the bug...really not sure what to buy next 🙈

Edited September 26, 2021 by tompato
Adding ISO

[Budgie1]

As your first go at a nebula you've done well. You're on target, the stars are round and you've got nebulosity. 

The stars look a little out of focus, so make sure to focus on a nice bright star like Vega and use the 10x zoom on the camera's live view to help. You don't say what ISO you were using but these EOS cameras seem to like ISO 800 or 1600 for most things. If the Moon is near full then you may want to cut the ISO and/or exposures a little, say 30 second exposures but lots of them.  

What to buy next; Maybe look at a light pollution filter for the camera, if you live in an area where LP is an issue?

Overall though, keep going and the more sessions you do, the more you'll learn. And if you haven't started already, try using some calibration frames (Darks & Flats to start with) in the stack;.

[tompato]

Oh yeah, they were at ISO 800! Yeah the moon was out so I think I might have needed shorter exposures like you say. I was hoping to get more shots in but the trees weren't having any of it!

I haven't done any flats yet in my couple of sessions I've done, I'm not sure the best way to do them other than to leave the camera out til the morning which I can't really do. Are there any good tips or tricks for doing flats?

I got one of those clip in filter holders that I can screw a 1.25" filter into from someone on this forum actually so I think I'll try and get one as there is a bit (not a massive amount) of light pollution.

[Budgie1]

1 hour ago, tompato said:

I was hoping to get more shots in but the trees weren't having any of it!

I'm a bit like that with Orion, I get about 2 hours of visibility between trees to work with!

1 hour ago, tompato said:

I haven't done any flats yet in my couple of sessions I've done, I'm not sure the best way to do them other than to leave the camera out til the morning which I can't really do. Are there any good tips or tricks for doing flats?

For flats, I removed the camera & lens complete from the mount (making sure not to alter the focus) then I used a blank MS Word document on my desktop screen and put a couple of layers of white t-shirt over the end of the lens. Put the camera into AV mode and use the same ISO settings as you did for the light frames. Take about 20 flats to start with and see what it's like when stacked.

I started using Dark frames as well but read that you can use Bias frames instead for the some DSLR's, so I tried that and didn't notice any difference from using Darks so stuck with just Flats, Dark Flats & Bias. This meant that I didn't have to spend time at the end of the session taking darks and could do the Bias frames the following day, along with the flats.

Bias frames are taken with the lens cap on and at a fast exposure, somewhere around 1/4000 is fine. Again, take about 20 of them as it doesn't take very long to do.

If you want to take Dark-Flats as well; These are taken at the same exposure & ISO settings as the Flats, only with the lens cap on. You can use TV Mode on the camera for this & the Bias frames. 

The link in my post above gives a good description of each type of frame and is what I used to get started.

Edited September 27, 2021 by Budgie1
Spelling

[AstroMuni]

On 26/09/2021 at 15:05, tompato said:

It was at f2.8 if I recall correctly and then a stacked, cropped and did some basic levels and tweaks in GIMP. (Edit - ISO 800)

Thats a great first attempt. What software did you use to stack?

[tompato]

On 27/09/2021 at 17:44, AstroMuni said:

Thats a great first attempt. What software did you use to stack?

I used Deep Sky Stacker to do the stacking. I did try Siril but it all seems far more complicated and I wasn't quite sure on settings etc, on DSS it seemed a bit more straight forward.

[AstroMuni]

14 hours ago, tompato said:

I used Deep Sky Stacker to do the stacking. I did try Siril but it all seems far more complicated and I wasn't quite sure on settings etc, on DSS it seemed a bit more straight forward.

This tutorial should help https://siril.org/tutorials/tuto-scripts/. It can do a bit more than DSS