Tips for wide field astrophotography with a dslr?

[Olli]

Hi there

 

i have recently acquired a dslr and looking to take some widefield shots of the night sky however at the moment I do not have a tracking mount. I was wonder if you guys have any tips for me ( such as what iso shutter speed ect to use ) as I’m pretty new to this stuff and not really sure what the limitations are without tracking. I only have a 18-55mm kit lens hoping to add more in the future.

 

Any help would be greatly appreciated 

[jambouk]

Have a read of this:

https://britastro.org/node/9282
 

James

[FenlandPaul]

The “rule of 400” is a great starting point. Keep your exposure to no longer than 400 divided by the focal length you’re using to avoid star trails. You could even push it to 500 for higher declination targets.

And worth getting to the darkest site you can.

Enjoy!!

[Olli]

18 minutes ago, FenlandPaul said:

The “rule of 400” is a great starting point. Keep your exposure to no longer than 400 divided by the focal length you’re using to avoid star trails. You could even push it to 500 for higher declination targets.

And worth getting to the darkest site you can.

Enjoy!!

Thank you for the advice, is there anything I have to do for focusing? Is there a certain point I should focus ? Where I live I have pretty dark skies but there’s a big field behind me which I’ll go to which seems darker!

[Olli]

53 minutes ago, jambouk said:

Have a read of this:

https://britastro.org/node/9282
 

James

Thank you for the link looks helpful will give it a proper read soon.

[Gfamily]

20 minutes ago, Olli said:

Thank you for the advice, is there anything I have to do for focusing? Is there a certain point I should focus ? Where I live I have pretty dark skies but there’s a big field behind me which I’ll go to which seems darker!

For focusing,  set your camera to Manual Focus, then set the focus ring to the infinity symbol. 

Next, mount your camera on a tripod, or equivalent, set the 'short' shutter setting (it doesn't need to be 10 seconds) and set the iso to a really high setting and take a 5 second exposure of the sky including some bright stars. 

Look at the shot just taken,  and use the image zoom to have a closer look at the bright stars near the centre. If they are tiny,  you're ok, but if they show as small circles, mske a small adjustment in one direction and repeat.

Compare the size of the star,  if larger, go the other way, if smaller, try a little  more and take another shot until it's as small as you can get. 

When done, without touching the focus ring, set the iso back to a lower level like 800 

Edited August 16, 2020 by Gfamily

[Olli]

12 minutes ago, Gfamily said:

For focusing,  set your camera to Manual Focus, then set the focus ring to the infinity symbol. 

Next, mount your camera on a tripod, or equivalent, set the 'short' shutter setting (it doesn't need to be 10 seconds) and set the iso to a really high setting and take a 5 second exposure of the sky including some bright stars. 

Look at the shot just taken,  and use the image zoom to have a closer look at the bright stars near the centre. If they are tiny,  you're ok, but if they show as small circles, mske a small adjustment in one direction and repeat.

Compare the size of the star,  if larger, go the other way, if smaller, try a little  more and take another shot until it's as small as you can get. 

When done, without touching the focus ring, set the iso back to a lower level like 800 

That’s extremely helpful, thank you.

[masjstovel]

12 hours ago, Olli said:

Thank you for the advice, is there anything I have to do for focusing? Is there a certain point I should focus ? Where I live I have pretty dark skies but there’s a big field behind me which I’ll go to which seems darker!

Which DSLR do you have? May be useful to know to be able to tip you of in what lenses to look for.
Which photos are you planning to take? Milky way? Sky only, or landscape-ish photos with "astro" backgrounds? 

If it has LiveView mode (a LCD screen with a live view): 
Turn off Autofocus, use manual focus. Point at a star, zoom all the way in on it or so far in you still can see the star clearly - with the screen zoom. This is usually + and - buttons near the screen. so NOT the lens zoom, but to zoom in on the screen.
Then you can manually focus until the star is at its smallest and its much easier to get better focus since your zoomed in. If you first going largely back and forth with the focus ring and then narrow it down, you should be able to get pretty pinpoint focus. 

As for settings; 

Run camera in Manual mode.

ISO:  depends on what camera you have, but most can do 3200 without too much grain, and some can do 6400++ with no problems. Try out test shots, zoom in on them and check. 
Aperture: Have your aperture wide open to gather as much light as you can. Still, depending on the lens, try not to go  past F/2.8 as youll get more easily bothered with chromatic abberation. I dont know your level of skill with photography, but thats F/[the lowest number you get]. 
Shutterspeed: For shutterspeed, the 400-rule/500-rule works if you dont have any trackingdevices. A Sky Watcher Star Adventurer, or Sky watcher Star Adventurer Mini could be worth checking out if youre not planning on getting a tracking mount for astronomy use. 

Other tips i find useful (again i dont know your skill-level in photography, but) :
-Always use a tripod for these kinds of shutterspeeds.
-If you dont have a remote control for shutter realease, consider getting one, or use time mode for shutter realease (ie 10 seconds) 
-Use Mirror Up mode (MUP) if your camera has it. (Then you need a remote control)
-Zoom in on your photos as you go along while on site. Alot of stuff look amazing on a 2" screen that doesnt in reality. 

Also, depending on your goal:  all good data from the photos needs to be post-processed in a post processing program like Photoshop fot example. Shoot in RAW mode to be able to process in the best possible way.

You could have more tips, but its all depending on your gear and on your "plan" ?


 

Edited August 17, 2020 by masjstovel