DSLR Single Exposure Targets

[Mikey0368]

Could someone recommend some deep sky targets that would give me a good outcome with a single exposure? I'm really only interested in checking my alignment, tracking and focus at the moment and I'll worry about stacking and processing once I know I'm getting something worthwhile to work with.

My camera is a modified Canon 600D and the scope is an 8" reflector on an HEQ5 Pro.

Thanks.

[carastro]

I presume you mean a single long exposure rather than a split second single exposure. 

M42 is a good one as it is bright.  Will be reasonable after 30 seconds. 

Carole 

[spillage]

Hi Mikey,

I would suggest M43 for starters as it only need a very short exposure time to get a result.

cheers

[Mikey0368]

That's great, thanks. There's a dirty great big bank of cloud moving in so it may have to wait, but I'll give them a go when I get the chance.

I'll post up my results to get some expert opinion!

[Stub Mandrel]

Other than M42, most globular clusters work well.

Tip - if just trying focus etc, use jpg +_ RAW. The JPG will get 'optimised' and you will see a lot more detail, although not as good for stacking.

[Mikey0368]

21 minutes ago, Stub Mandrel said:

Other than M42, most globular clusters work well.

Tip - if just trying focus etc, use jpg +_ RAW. The JPG will get 'optimised' and you will see a lot more detail, although not as good for stacking.

Thanks, I may try that too as M42 and M43 won't appear round the side of our neighbour's house until after 10pm! Anything towards the west would be better.

There's a lot of cloud cover here now so tonight is looking increasingly unlikely.

[tasheeya]

17 hours ago, Mikey07 said:

Thanks, I may try that too as M42 and M43 won't appear round the side of our neighbour's house until after 10pm! Anything towards the west would be better.

There's a lot of cloud cover here now so tonight is looking increasingly unlikely.

Andromeda should be an easy bright target in the west if you want to try before 10pm

[tasheeya]

also double clusters or Pleiades but don't expect nebulasity in short exposes.

[Mikey0368]

The clouds finally cleared!

I'm quite happy with my alignment. I put Mars in the middle of the viewer, went out for an hour and it was still pretty central when I got back. I also got myself a Bahtinov Mask for focus and tonight was the first time I've used it!

So I have 8x18 secs (JPG and RAW) of M31. Here's an example of one of the JPG images, could someone cast their eye over it for me and let me know if it looks like I could get something useful out of my 8 RAW images?

Thanks again.

[wxsatuser]

Cannot get much out of it as quite short subs but some lanes just showing and M110 towards bottom.
You have some coma as well.

[Mikey0368]

Thanks. I'll have another go with a longer exposure.

[Stub Mandrel]

If I were you, I'd think hard about getting more subs. You can always leave them to one side until you want to start processing. These odd clear nights are a precious opportunity.

[Mikey0368]

It was great here last night so I was able to spend a bit of time on M31. I got 20 x 60s subs and I've stacked them using DeepSkyStacker, giving me a 157mb .tif file. I have GIMP installed as well but don't really know where to start with it. The first question is, will I be able to get anything out of what I have?.... 

https://farm8.staticflickr.com/7884/46034388025_3b78ca1549_c.jpg

…..And if so, what sort of adjustments do I need to make to the image?

Thanks again.

[don4l]

1 hour ago, Mikey07 said:

It was great here last night so I was able to spend a bit of time on M31. I got 20 x 60s subs and I've stacked them using DeepSkyStacker, giving me a 157mb .tif file. I have GIMP installed as well but don't really know where to start with it. The first question is, will I be able to get anything out of what I have?.... 

https://farm8.staticflickr.com/7884/46034388025_3b78ca1549_c.jpg

…..And if so, what sort of adjustments do I need to make to the image?

Thanks again.

 

Check that you have version 2.10 of Gimp.  Earlier versions were 8 bit which is next to useless.

 

Open the image and click "Colours -> Levels".  Click the button marked ""Auto Input Channels".  This will show you if there is much data to play with.  It doesn't usually produce anything pretty, but it should show if you have useful information to work on.

If the "Auto..." button does show that there is useful stuff, then click "Reset" and play with the sliders in the "Input Levels" area.  Make multiple small adjustments instead of one large one.

 

[Mikey0368]

Thanks, I'll have a look at that tonight as it looks like I won't be spending much time outside. I got myself Polar aligned just as it was getting dark, so I could try for longer exposures, but the clouds have rolled in!