Frequently asked questions

Yes. Drop in a stacked FITS, XISF or TIFF from a Seestar or Dwarf, Siril, DeepSkyStacker, ASTAP, Astro Pixel Processor or PixInsight, and Akastroid does the rest: gradient removal, photometric color calibration against the star catalog, deconvolution, the stretch, sharpening, star handling and annotation. It reads the file to work out what it has been given: a 32-bit float stack is still linear, so it gets the full finishing pipeline, while an already-stretched 8 or 16-bit picture is treated as somebody's finished image and only touched up. Getting that wrong is how a stack comes out green and dark, so it is decided from the file rather than guessed from how bright the sky looks.

Point Akastroid at the folder your camera or smart telescope wrote and press Process. Nothing needs to be renamed, converted or configured first, and you do not need to know what the processing steps are. They are set from measurements of your frames and listed afterwards with the reason for each. If you would rather understand the workflow first, it is written out step by step on the How it works page.

No. If you have them, put them in folders called darks/ and flats/ next to your lights and Akastroid finds and applies them. If you don't, it says so once and carries on, and you still get an image.

No. Your frames are read, processed and written on your own machine, and nothing about them is ever uploaded. The application makes three kinds of network request, and none of them carries your images: an update check, which you can switch off under Help; a one-time report that this version opened successfully, behind the same switch; and a licence activation, only if you enter a key. With the update switch off and no key entered, it makes none at all. It works with the wifi off, and it would keep working if this website went away.

No. There is no neural network anywhere in Akastroid, no trained model weights ship with it, and nothing is downloaded at runtime. You can check the installer yourself. What it does is measure your data and do arithmetic on it: which frames are sharp, how noisy the stack is, where the sky gradient sits, how far to stretch. That is statistics and optics. It matters because AI sharpeners and star removers can add plausible structure that was never photographed. If you submit images to a competition or a survey that asks whether AI was used, the answer for Akastroid is no.

Siril is excellent and will go further than Akastroid in expert hands. The difference is the learning curve: Siril expects you to know the sequence of operations and their parameters. Akastroid works those out, runs them, and tells you what it did. Measured on the public M42 LRGB dataset against Siril 1.4.4 in October 2026, star width on the mono stack was level (1.64 px against Siril's 1.67 px half-width), as was colour-channel alignment (0.17 px against 0.18 px median). Akastroid's mono star signal-to-noise was 0.90 to 0.92 of Siril's; it stacked 46 of the 51 frames where Siril used all 51. If you already know Siril you may not need this.

Yes. Point it at the folder of FITS files the Seestar saves. It reads the Bayer pattern, exposure, gain and pointing coordinates straight from the headers. Use version 1.3.13 or later: one folder can then hold frames taken with and without the light pollution filter (LP and IRCUT), and mosaic frames, which show another part of the sky, are set aside with a note saying how many.

Yes: Canon CR2 and CR3, Nikon NEF, Sony ARW, Fujifilm RAF, Olympus ORF, Panasonic RW2, Pentax PEF and DNG among others. It reads the sensor data with the black level removed and nothing else done to it, which is what stacking needs. A normal RAW converter's white balance and gamma are wrong for a stack of 60-second exposures.

Drop in a .ser or .avi capture. Akastroid grades every frame for sharpness, keeps the best, aligns them on the planet's disc in pieces to remove the atmosphere's local warping, corrects atmospheric dispersion and sharpens with wavelet layers you control. In most workflows that takes several separate programs.

A hundred-frame DSLR session takes under a minute on an M-series Mac. A 206-frame Seestar session measured 22 seconds, and 111 DSLR raws 70 seconds. A planetary capture of twenty-six thousand frames measured 82 seconds. Drizzle is the slow part: about 1,000 Seestar frames took 29 minutes with it on, and switching it off before the run makes that much shorter.

Stacking caches every registered frame on disk, roughly width × height × channels × 2 bytes each, so a 134-frame DSLR session is about 6.5 GB. Akastroid checks before it starts and, if there is not enough room, keeps the best frames that fit and tells you rather than failing part-way.

No. Pro is one payment, yours permanently. (If you would rather spread the cost, Pro Monthly is $11.99 a month, cancel any time; it works while it is paid for and then goes back to the free allowance.) Pro covers one computer at a time and Pro Studio covers two, and neither is tied to an operating system. One key activates any build, so moving from a Mac to a Windows machine costs nothing. Another machine is a transfer, not a second purchase: deactivate on the old one and activate on the new one, as often as you like. Every future version is free, version 2 and later included. You never pay for an upgrade.

The free version has no time limit. Every feature works: deep sky, planets, the Moon and the Sun, drizzle, mosaic stitching, photometric color calibration, annotation, gift artwork and 16-bit export. It is capped at five processing runs (deep-sky or planetary) and three exports. A run that fails or that you cancel does not count (version 1.3.13 and later). A licence removes both limits. If you buy and it still isn't right, email within 14 days for a refund. That applies in every country.

macOS remembers that permission for one exact build of an app, and Akastroid is not signed with an Apple developer certificate yet, so each new version counts as a new app. Click Allow once after each update. Keeping Akastroid in Applications rather than on the Desktop also means fewer of these questions.

They are your photographs. Akastroid claims nothing.