Starry Sky Stacker is astrophotography stacking app for macOS written by Ralph Hill. It has multiple functions for creating good quality stacks for further processing: Combining single exposures using different algorithms (you can choose which one you want to use) - median, mean, max, or min Aligning your subs if they were not tracked accurately.

'Bonsai Rock Under The Stars' is a 5-image stack with Sequator to reduce noise in the sky ~ © Michael Ver Sprill‎ (this is a cropped version - original can be seen on the NightScaper Facebook group)

Starry Landscape Stacker is a nice program if you do astrophotography with some terestial objects in the foreground. Normally it will swallow about 15 images.after that, it tends to give problems when trying to stack. Deep Sky Stacker.nice but old software.
In this vid I'll be showing the difference between stacking images in photoshop & Starry Landscape Stacker (only available for Mac).Music: https://www.youtub.

Sequator is a free Windows / PC software which can track stars on multiple images, align stars and stack them. According to Michael Ver Sprill, it is the first PC software he has found that favorably compares to Starry Landscape Stacker for the Mac! Stacker

“I typically use my iMac for editing stacked images and a program called Starry Landscape Stacker which really helps reduce noise and maintain sharpness. However it is for Apple computers only until I came across SEQUATOR. This program is very similar to SLS. The results were practically identical and this seems to be a great alternative for PC users,” says Mike.
“This program is very similar to SLS. The results were practically identical and this seems to be a great alternative for PC users.”
Mac

Video Tutorial: Mike has put together a YouTube tutorial that will help you properly install and use Sequator.
Sequator vs. Fitswork:Ralf Rohner has done a nice job comparing Sequator with Fitswork, another popular Windows based star stacking program. He highly recommends Sequator to process an untracked image sequence. 'On Windows, it is by far the easiest to use and fastest stacking software for nightscapes and produces very good results. Even beginners can immediately produce excellent results. There are no excuses anymore for noisy single shot nightsapes,' says Ralf.
Landscape

Ralf found Sequator “...really easy to use and it took me less than 5 minutes to produce the result, while my normal workflow in Fitswork takes about 3 hours to arrive at the same stage…The only point where I disagree Mike, is that for better sharpness and less no burned highlights, I recommend to use HDR instead of Auto Brightness.”

For a more detailed comparison, refer to Ralf's Flickr post ~ © Ralf Rohner

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Starry Landscape Stacker Mac Review

Starry Landscape Stacker For Mac