Usage
The Bin module is operated with just a single parameter; the 'Scale' parameter. This parameter controls the amount of binning that is performed on the data. The new resolution is displayed ('New Image Size X x Y') , as well the single axis scale reduction, the Signal-to-Noise-Ratio improvement and the increased bit-depth of the new image.
When to bin?
Data binning is a data pre-processing technique used to reduce the effects of minor observation errors. Many astrophotographers are familiar with the virtues of hardware binning. The latter pools the value of 4 (or more) CCD pixels before the final value is read. Because reading introduces noise by itself, pooling the value of 4 or more pixels reduces this 'read noise' also by a factor of 4 (one read is now sufficient, instead of having to do 4). Ofcourse, by pooling 4 pixels, the final resolution is also reduced by a factor of 4. There are many, many factors that influence hardware binning and Steve Cannistra has done a wonderful write-up on the subject on his starrywonders.com website. It also appears that the merits of hardware binning are heavily dependent on the instrument and the chip used.
Most OSCs (One-Shot-Color) and DSLR do not offer any sort of hardware binning in color, due to the presence of a Bayer matrix; binning adjacent pixels makes no sense, as they alternate in the color that they pick up. The best we can do in that case is create a grayscale blend out of them. So hardware binning is out of the question for these instruments.
So why does StarTools offer software binning? Firstly, because it allows us to trade resolution for noise reduction. By grouping multiple pixels into 1, a more accurate 'super pixel' is created that pools multiple measurements into one. Note that we are actually free to use any statistical reduction method that we want. Take for example this 2 by 2 patch of pixels;
7 7
3 7
A 'super pixel' that uses simple averaging yields (7 + 7 + 3 + 7) / 4 = 6. If we suppose the '3' is anomalous value due to noise and '7' is correct, then we can see here how the other 3 readings 'pull up' the average value to 6; pretty darn close to 7.
We could use a different statistical reduction method (for example taking the median of the 4 values) which would yield 7, etc. The important thing is that grouping values like this tends to filter out outliers and make your super pixel value more precise.
Sensor resolution may be going up, but the atmosphere's resolution will forever remain the same - buying a higher resolution instrument will do nothing for the detail in your data in that case!
Binning and the loss of resolution
But what about the downside of losing resolution? That super high resolution may have actually been going to waste! If for example your CCD can resolve detail at 0.5 arcsecs per pixel, but your seeing is at best 2.0 arcsecs, then you effectively have 4 times more pixels than you need to record one 1 unit of real resolvable celestial detail. Your image will be "oversampled", meaning that you have allocated more resolution than the signal really will ever require. When that happens, you can zoom in into your data and you will notice that all fine detail looks blurry and smeared out over multiple pixels. And with the latest DSLRS having sensors that count 20 million pixels and up, you can bet that most of this resolution will be going to waste at even the most moderate magnification. Sensor resolution may be going up, but the atmosphere's resolution will forever remain the same - buying a higher resolution instrument will do nothing for the detail in your data in that case! This is also the reason why professional CCDs are typically much lower in resolution; the manufacturers rather use the surface area of the chip for coarser but more deeper, more precise CDD wells ('pixels') than squeezing in a lot of very imprecise (noisy) CCD wells (it has to be said the latter is a slight oversimplification of the various factors that determine photon collection, but it tends to hold).
Binning to undo the effects of debayering interpolation
There is one other reason to bin OSC and DSLR data to at least 25% of its original resolution; the presence of a bayer matrix means that (assuming an RGGB matrix) after applying a debayering (aka 'demosaicing') algorithm, 75% of all red pixels, 50% of all green pixels, and another 75% of all blue pixels are completely made up!
Granted, your 16MP camera may have a native resolution of 16 million pixels, however it has to divide these 16 million pixels up between the red, green and blue channels! Here is another very good reason why you might not want to keep your image at native resolution. Binning to 25% of native resolution will ensure that each pixel corresponds to one real recorded pixel in the red channel, one real recorded pixel in the blue channel and two pixels in the green channel (the latter yielding a 50% noise reduction in the green channel).
There are, however, instances where the interpolation can be undone if enough frames are available (through sub-pixel dithering) to have exposed all sub-pixels of the bayer matrix to real data in the scene (drizzling).
Fractional binning
StarTools' binning algorithm is a bit special in that it allows you to apply 'fractional' binning; you're not stuck with pre-determined factors (ex. 2x2, 3x3 or 4x4). You can bin exactly the amount that achieves a single unit of celestial detail in a single pixel. In order to see what that limit is, you simply keep reducing resolution until no blurriness can be detected when zooming into the image. Fine detail (not noise!) should look crisp. However, you may decide to leave a little bit of blurriness to see if you can bring out more detail using deconvolution.
Download
One ZIP archive contains Windows, macOS and Linux versions of StarTools. Do not download StarTools from anywhere else but startools.org. We do not allow distribution of StarTools by any other party, on-line or off-line.
Please consult the FAQ section about configuring your system properly.
macOS notes
Users may have to "unquarantine" StarTools, before the OS allows it to run. Alternatively StarTools can be launched via control + clicking (right clicking) on the application, Show Package Contents, navigating to Contents/MacOS and clicking on the application.
The following two commands unquarantines StarTools on macOS 13 Ventura and later;
sudo xattr -d -rs com.apple.quarantine StarTools.app
and then;
sudo xattr -d -rs com.apple.provenance StarTools.app
The following single command unquarantines StarTools on macOS 12 and earlier;
xattr -dr com.apple.quarantine StarTools.app
Please see the screenshots for more information, or download this detailed guide.
Download stable
StarTools 1.8.527 Maintenance Release 3 for Windows, macOS (Universal Binary with native M1 support), and Linux
Latest version released 2023-11-15 (YYYY/MM/DD), size 6.8MB
Download bleeding edge
StarTools 1.9.565 Beta 7 for Windows, macOS (Universal Binary with native M1/M2 support), and Linux
Multi-language support EN, DE, ES is available via config file
Latest version released 2024-03-24 (YYYY/MM/DD), size 7.1MB
Please note beta versions may still exhibit some flaws or instabilities. Documentation may be incomplete. Please use at your own risk.
Unofficial English manual
Unofficial English StarTools 1.8 Manual (164MB), last updated 2022-09-30, improved with extra tips, tricks and information from various sources.
Many thanks to J. Scharmann for putting together this excellent work, as well as its German translation.
Unofficial German manual / Inoffizielle Deutsche Anleitung
Inoffizielle StarTools 1.8 Anleitung in Deutsch (164MB), letztes Update 2022-09-30.
Vielen Dank an J. Scharmann für die ausgezeichnete Übersetzung.
Unoffical Spanish manual / Manual en Espanol
Manual de StarToolsBasado en la versión 1.8 al español (19MB). Ultima actualizacion 2022-03-09.
Muchas gracias a C. R. Guixé por la excelente traducción.
English manual
StarTools uses AIFE.AI for content management and digital footprint. This means that the website content doubles as a printable manual and vice-versa. This content is also available as a smartphone/tablet app, virtual flipbook, virtual reality (VR) experience and more. This content will always be up-to-date with the latest information.
The minimum specifications to run StarTools, increases with the resolution of the dataset you intend to process.
StarTools works on all modern versions of Windows, Linux and macOS.
StarTools is display-device agnostic, but can be configured to display its GUI at a 4x higher resolution to accommodate high-DPI devices and 4K displays.
If StarTools appears to be unstable on your older (up to 2014) macOS device, particularly when using bigger datasets, then this may be due to an underpowered iGPU solution. Particularly the second and third generation Intel-based macOS devices are equipped with minimal GPU acceleration.
If your older or lower-powered GPU or iGPU appears to be unstable on your Windows operating system in StarTools, and you think it may be struggling with any larger datasets you give it, then the issue may be caused an unsuitable Timeout Detection and Recovery (TDR) allowance.
If you find StarTools sometimes crashes under heavy load in demanding modules like SVDecon, this may be due to your Operating System being incorrectly configured to provide enough virtual memory.
Some less reputable virus scanners such as BitDefender, Norton and SpyBot may falsely report StarTools as a Trojan or Potentially Unwanted Program (due to malware that carries a similar name). Despite multiple users going through the lengths of getting StarTools white listed, the same problem pops up every 6 months or so.
StarTools uses all your CPU's cores to speed up processing in situations where it makes sense. As of 1.7, however, StarTools will offload suitable, heavy arithmetic to your GPU as well.
As of version 1.7, StarTools offloads suitable, heavy arithmetic to your system's GPU.
StarTools supports virtually all modern GPUs and iGPUs on all modern Operating Systems.
StarTools is a completely native, self-contained application that does not require any further installation of helper libraries or run-time frameworks.
StarTools is a unique piece of software that keeps track of signal evolution and noise propagation. The data it needs to store and access may grow to many gigabytes. As such StarTools uses your storage memory (hard drive or SSD drive) to store this data. If StarTools is unable to write this data, a message may appear alerting you to this.
If you had bothered to read the 'buy' page, you would have learned that you could spare yourself the effort of writing a keygen or crack - if you can't afford the license fee and you are a genuine enthusiast, we're happy to work something out!