Akastroid vs RegiStax

They do different jobs

RegiStax is used today mostly for one stage: wavelet sharpening of an already-stacked planet, usually stacked in AutoStakkert. Akastroid is the whole chain - grading, stacking, dispersion correction and sharpening - for planets and for deep sky, in one application on Mac and Windows.

So the honest comparison is narrow: six sliders you set against a sharpening strength measured from the stack.

Sliders, or a measurement

RegiStax gives you six wavelet layers and lets you take any of them as far as you like. In experienced hands that is control nothing automatic can match, and it is why the tool has outlived its own operating system. It also has no idea what your stack can support, so overdone wavelets - bright rims around every belt, a ringing limb - are the single most common way a good planetary capture is spoiled.

Akastroid measures instead: how much fine detail the stack actually holds, how much noise sharpening would amplify, and whether the limb starts to ring. The strengths follow from that, and the guard that declines to sharpen a stack that cannot take it is the part with no equivalent in a slider.

Why there is no number on this page

Everywhere else on this site a comparison comes with a measurement - see the AutoStakkert page, which reports where we lose as well as where we win. RegiStax has not been measured against Akastroid: it needs a working Wine to run here, and its wavelet step has no batch interface, so any result would depend on where somebody put the sliders that day. Publishing a number like that would be inventing one.

When a real RegiStax output exists to measure against, the number goes here, whichever way it falls.

Use both, if you like

Akastroid's stacked export is linear 32-bit data, written so another program can pick it up. Stack here, sharpen in RegiStax, or the other way round - nothing in either tool requires the whole workflow.

Questions

Is Akastroid sharper than RegiStax?

Unmeasured, so no claim is made. RegiStax sharpens with wavelets you set by hand, which means any comparison depends entirely on where somebody put six sliders - and it has no batch interface to do that fairly across captures. Akastroid measures the stack and chooses the per-scale strengths from it. Different approaches; only one of them has numbers on this site, and it is the AutoStakkert comparison.

Does RegiStax still work?

Yes. RegiStax 6 is from 2011, it is Windows-only, and its wavelet sharpening is still excellent - which is why it is still recommended fifteen years later. Being old is not the same as being wrong.

What does Akastroid do instead of wavelet sliders?

The same idea, decided rather than dialled: the stack is split into scales and each is sharpened, with the strength set from what the stack can support - how much real detail it holds and how much noise it would amplify. The Sharpness control moves all of it together in four steps, and the detailed rows are there when you disagree. What you cannot do is spend an evening on six sliders, which is either the loss or the point depending on the person.

Can I use both?

Yes, and some people should. Export the stack as a 32-bit float TIFF or a FITS master and sharpen it wherever you like - Akastroid's stacked export is linear data written for exactly that. Nothing about using Akastroid to stack commits you to its finishing.

Does RegiStax run on a Mac?

Not natively - it needs Wine, CrossOver or a virtual machine, and Wine on recent macOS has been awkward. That is the practical reason a Mac planetary imager ends up looking for something else, more than any feature.

The planetary path is described on the planetary page, and how wavelets and dispersion correction actually work is the guide behind it. Download for Mac and sharpen a capture you have already done in RegiStax - your own eyes on your own data settle it faster than any page.