beginner software advice

[graham.hobart]

Hello Team!
I am after some advice for processing software. I have been using nebulosity up till now. I downloaded StarTools but it seems to run terrifically slowly on OS X. I do have access to a vista computer.
I am after something not as expensive as photoshop which I saw would cost nearly $1000. I have heard of GIMP- anyone any advice about that?
Also can you use astronomy specific add ons in GIMP like in photoshop?
I don't mind buying the licence but preferably not a grands worth!
TTFN
graham

[garymck]

Try Iris, its an extraordinarily powerful program, but with a quirky interface, and it's free.

http://www.astrosurf.com/buil/us/iris/iris.htm

If you have some dollars budgeted I would suggest ImagesPlus from:

http://www.mlunsold.com/

It is very easy to use, and deceptively powerful. Makes it easy to get nice results. Arguably ot as good as if you are a Photoshop expert, but I'm not so I like it!

FWIW
Gary

[graham.hobart]

That sounds like a plan- thanks
will investigate Iris first I think

[irwjager]

Hi Graham,

The GIMP is great for bright objects such as planets, so by all means, give it a try! I would especially recommend the GMIC plug-in (amongst other things it does deconvolution which is virtually a must for planetary imaging!). However, for now the GIMP only supports 8-bit images, which is insufficient for deep space objects, which typically require much higher signal resolution (due to them being so faint). Level stretching faint objects will result in severe banding and rounding errors, making most results pretty much unusable.

One of the biggest hurdles in using generic image processing packages such as the GIMP, PhotoShop, PaintShop Pro, Krita, etc. etc. for astro work, is getting your head around the things that you shouldn't do. As a beginner, destroying your data early on during processing is unfortunately all too easy using these programs. Tutorials will help you here though. Dedicated astro packages (mostly) dispense with any signal destroying functions and focus much more on retaining your signal fidelity and making the most of any faint signal you may have lurking in your data set. The latter is usually where 90% of the hard work is!

You can't really go wrong with most of the astro-specific programs out there. AIP4WIN (Windows only though) is rather interesting as well - it comes with a well written book that touches (in depth) on all subjects relating to astro-imaging. If you think you can deal with the steep learning curve and (IMHO) everything-and-the-kitchen-sink interface, PixInsight is worth considering, very capable and still much cheaper than a a PhotoShop license.

By the way, if StarTools does not perform to satisfaction (even after using the trial version), I'm happy to give you a refund! :) One of the first questions in the StarTools FAQ on the website is "Why is ST so slow?". The answer is that all of its modules/functions perform multiple algorithms and steps at once in the interest of signal fidelity and automation. It's totally possible to bring the latest Quad Core i7 CPU to its knees.

The philosophy in ST is that, if you want to make the most of your signal, it's better to perform as many functions as possible in parallel at once, rather than sequentially. Less tweaking means a better signal fidelity (less rounding errors) and getting to your final image quicker (it's easier to evaluate more what-if scenarios and avoid 'overcooking' your image - a common beginner mistake). The automation takes a bit of CPU power as well, but it means you're not going to have to worry about evaluating histograms, signal clipping or even things like local stretching/masking and (coming soon) local sharpening. Most other software does not provide any advantage to people with modern CPUs and/or multiple cores - they just perform the same old algorithms (which mostly haven't changed since the 90s) a bit faster but don't offer any other benefits.

Hope this helps!

Cheers,