Stacking v long exposure

[Rogerw]

Ive just joined this forum and thought I would start with a question.  What to people think is best for wide field shots of the milkyway etc lots of short exposures, say 20 sec x 40 images or one exposure of equivilent time approx 10 mins.  I have a Nikon D5300 which has one of the newer sony low noise sensors I believe, but I was considering getting a Star Adventurer if it would give better results than what I have been doing up to now which is stacking in DSS .

Roger

 

[wxsatuser]

Exposure depends on a few things, sky brightness, optics and tracking ability spring to mind.

IMO we should first look for the correct exposure, the correct exposure will give the length of exposure.
Just because we can take a 10minute exposure does'nt mean it's correct or right to do so.

Breaking an exposure into subs is perfectly ok, remember, it's total exposure that counts.
Do remember, very short subs won't match longer subs no matter how many you stack.

I have found here that correct exposures in the range of 2 to 5minutes with a total exposure in excess
of 2hours will give pretty good results. You can of course go over or under this, depending on the quality
of image you want or expect.
 

[hjw]

Hi Roger and welcome to the forum!

I think it is very much depending on what you want to achieve. If you are after a milky way panorama shot stacked short exposures are fine. But if you are interested in the different structures of the milky way the process is closer to a standard DSO. I have jsut started a project which I intend to go over the next few month - taking a mosaic of the milky way from Carina past Sagittarius. Here is the first panel taken with the Pentax K-30 and a DA 50mm f/1.8 lens stepped down to f/3.2. 30 frames of 180sec each at ISO400. It's a 1 1/2 hour exposure time and I was hoping for more contrast between the dust clouds and the background. So, 90 minutes might not be enough... I also think I can do a bit more in terms of processing.

Good luck and clear skies!

HJ

 

[Rogerw]

Very nice image , lots of colour and definition.

Here is one of my attempts, taken in South Island New Zealand My first attempts at astro photography with this camera and I was amazed at what the modern cameras can do.  This was about 30 images at 20 sec stacked in DSS and mainly processed in Light Room.  Nikon D5300 with std. 18-55mm lens at 18mm.

Nothing like what can be done but I want to keep the kit light so I can travel with it.

[hjw]

I think that's a great picture. I especially like the Large Magellanic Cloud in the top right :). Incidentally, it is the same part of the Milky Way as my shot and highlights well the difference in approach. My setup was definitely NOT  travel friendly.

Cheers

HJ

[Scott]

It's always nice to get as long as is reasonably possible but why stop at 1  . if you can get a 10 min sub, get 10 or 20 or 30. A couple of years ago, I was on hols in france and it was the first time I was able to get 10min (or was it 15) subs so I did about 3hrs and whilst there are dodgy star due to itbeing a cheap lens, its my best attempt imho. It's no winner but it made me happy

[Damphir]

Hello! Rogerw, please tell me what settings you had for taking the pictures (iso, f/?, etc.). I have the same Nikon D5300 with the same 18-55 lens and I want to start taking photos of the night sky. Thank you!

[ollypenrice]

Find the optimal exposure time by experiment and then take a lot of them! The brightest parts will become a little brighter still in the stacking so leave a small margin to allow for this.

Obviously the longer expsures will go deeper but this can mean your skyglow can start to set an upper limit. Also you'll need to track to take longer subs. Using a very short FL lens at my dark site I helped some guests with DSLR Milky Way shots. They were running unguided on a humble driven EQ3 but this allowed stacks of 5 min subs to be combined with tight stars and a good reach into the deep objects. Be aware that focus is ultra critical. If you don't have something like FWHM to help you than the very expert Melsky, on here, suggests zooming into a star right to pixel scale and getting it as small as possible that way. Seems like a sound idea. 

Olly