Replaced the median composition algorithms with variations on truncated mean that should result in slightly better results. Added support for 32-bit floating point output. This should improve image quality when there are a large number of input images and the noise in the input images is small. 32-bit output is off by default. It can be turned on in settings. See details online before turning it on--32-bit float data is not well supported in many image editing apps. Added support for lens distortion correction when processing RAW images. Lens distortion correction is off by default. See details online before turning it on. Bug fixes and significant internal changes to facilitate future upgrades. See full details at https://sites.google.com/site/starrylandscapestacker/new-in-version-1-10

Fixed a problem that would cause Starry Landscape Stacker to crash during the alignment phase if the image files did not have a capture time and there was not enough memory to process the images in memory. Fixed a problem in some warning messages where the “Ok” button would be hidden if a large number of image files were being processed.

Improved alignment with images that are very noisy or images with diffuse stars as might be seen in reflections. EXIF data is no longer required in the image files but is highly recommended. If there is no EXIF data several parameters describing the camera have to be guessed. Sometimes the guess is wrong resulting in poor performance. Fixed a problem that could occur when there are mutually contradictory metadata values in the EXIF data. The minimum supported OS version is now macOS 10.14.6. It was 10.11. The Apple development tools no longer support OS versions before 10.13 and recommend 10.14.6.

Update to the alignment algorithm to correct a problem with bad alignment that was seen on some M1 Macs. Reduced memory usage, particularly in the case where intermediate results are stored in a temp file instead of in memory.

Improvements have been made to the alignment algorithm so that it works better with images where the time between the first and the last image is longer than 10 minutes. Alignment is also faster in most cases now.

• The alignment algorithm has been replaced. The new algorithm works much better with images that have few sharp stars to align. It is also much faster. • The limits on the values for white balance during RAW conversion have been broadened to support the use of light-pollution filters. • Fixed some issues with saving the preferences. • Fixed a some UI issues with the image classification panel.

Built for M1 Macs. I do not have an M1 Mac and cannot test this. Please send me mail if you have an M1 Mac and experience any difficulties. Fixed a problem that could cause a crash if there was a problem aligning the images. Minor UI changes to work better with macOS 11. Other minor bug fixes and UI adjustments.

Fixing two problems with version 1.9.2. A string displayed in the user interface that was accidentally deleted has been restored. The links to documentation have been improved. New in version 1.9.0 - RAW files are now supported for a wide range of cameras. - A novel processing technique for dark frames has been added that results in very good correction of hot pixels and sensor glow with a small number of dark frames. - The workflow part of the user interface has been updated. - A problem with crashing when run on certain combinations of operating system and graphics hardware has been fixed. Full Details: https://sites.google.com/site/starrylandscapestacker/new-in-version-1-9

Fixing a bug in version 1.9.0. The radio buttons that control painting vs. erasing the mask could get out of sync. New in version 1.9.0 - RAW files are now supported for a wide range of cameras. - A novel processing technique for dark frames has been added that results in very good correction of hot pixels and sensor glow with a small number of dark frames. - The workflow part of the user interface has been updated. - A problem with crashing when run on certain combinations of operating system and graphics hardware has been fixed. Full Details: https://sites.google.com/site/starrylandscapestacker/new-in-version-1-9

- RAW files are now supported for a wide range of cameras. - A novel processing technique for dark frames has been added that results in very good correction of hot pixels and sensor glow with a small number of dark frames. - The workflow part of the user interface has been updated. - A problem with crashing when run on certain combinations of operating system and graphics hardware has been fixed. Full Details: https://sites.google.com/site/starrylandscapestacker/new-in-version-1-9

Display update for almost all tasks is much faster, especially for MacOS 10.14 (Mojave) and later. Pinch zooming is now supported. Zoom level is displayed as a percentage, and can be typed in. Undo/redo of painting and erasing of red dots is by stroke (mouse down to mouse up) rather than by individual point. This should be faster and more convenient for most users. Alignment and composition is typically more than 2x faster than version 1.7. Improved alignment where there are few stars to align (e.g., corners with vignetting). Changing images (with next/prev and arrow buttons) can be slightly slower. (This is a trade off with faster drawing in general). SLS can no longer align images where the camera moved so much that you can see movement at the horizon in the images. Other bugs fixes and UI improvements. Starry Landscape Stacker now requires Mac OS 10.10 or newer. (Was 10.8 or newer).

The steps needed to make the mask for the sky should go more quickly now. Placement of the red dots in the sky is faster and better. Finding the mask is now faster and better. There are slightly different controls for placing red dots and finding the mask. The composition algorithms have been changed. There is an option to control the trade-off between star duplication and noise at the boundary between sky and ground. Alignment is faster, typically by about 20%. The alignment results are better when there are few visible stars or a lot of noise. Variable zoom levels are now supported. Other fixes and improvements. Full details here: https://sites.google.com/site/starrylandscapestacker/new-in-version-1-7

Fixed an error that caused alignment to fail if both the time between the exposures was too large (30 to 40 seconds was probably the limit) and the EXIF data did not have the sensor resolution (many cameras include this information in the EXIF data, but some cameras and/or RAW processors do not). Starry Landscape Stacker is now more tolerant of inconsistencies in alpha channels generated by ON1.

Light frames may now have alpha channels. This is important for users of RAW converters that always include an alpha channel even if there is no mask. (For example, ON1 and Photos alway include an alpha channel). It is strongly preferred to use tiff files without alpha as the files are 33% smaller and more than 33% faster to read. There is a new restriction—if all of your images have an alpha channel and you want to supply a mask that marks the whole image as sky, that mask file must be a monochrome bit map. Fixed some problems with handling of the boundary between sky and ground. Image quality in this area is much better. Fixed some errors with computing and reporting required temporary file space. Fixed a problem dealing with incomplete EXIF data from some older cameras.

- Fixed an error that could cause a crash when processing certain images using temp files. - Reduced the maximum amount that exposures can very within a group of images before warning the user. The maximum was set too high, occasionally resulting in artifacts in the final image without first warning the user.

- Very large numbers of images can now be stacked on computers with little memory because temporary files will be used instead of memory, if necessary. - Improved alignment and composition at the boundary between sky and ground. - Improved alignment under a wide range of conditions. - If the focal length of the lens is not found in the EXIF information the user is required to type in the focal length of the lens.

- Fixed errors in reporting of errors in input files that could cause a crash. - Other bug fixes.

- If you have an image where you like the way the stars are lined up with things on the ground you can select this image to be the one that the others are aligned with. - Four different compositions are computed and can be saved. This makes it easier to include satellites and meteors in a final image created with an image editing tool. - There is a check box at the bottom of the open panel to force classification table to be displayed. - In the classification table, clicking on a column heading now changes the classification of each image that can be change to that classification. - Improved efficiency of memory usage--typically more than a 50% reduction in peak memory usage. - Performance improvements--typically more than 2x faster alignment than SLS 1.4.5. - Huge improvement in redraw performance resulting in much faster scrolling, zooming, painting, erasing and adjustment of viewing parameters. - The alignment algorithm is much more tolerant of widely varying sensor and lens characteristics. - Other minor improvements and bug fixes.

The automatically generated file name for the image with the mask has been changed to ...-mask. It was ...-sky. I made this changed because sometimes you will generate a file with the stars in the sky aligned and another file with the stars in the reflections aligned. The old naming made it difficult to name the image files and the mask files unambiguously. Starry Landscape Stacker will now refuse to align images where the elapsed time is greater than 20 minutes as attempting to align these images requires huge amounts of memory and usually exceeds system resources. Alignment is now faster when there are more than 5 light frames and there are regions of sky that are difficult to align due to fog, clouds, etc. Peak memory usage during alignment has been reduced at least 20%. In some cases, such as images that are difficult to align or taken over a long period of time, the reduction can exceed 50%. (Processing 14 images of 50Mpixel each that are easily aligned now uses a maximum of 14.3 Gbytes. Processing the same files with version 1.4.4 requires over 21 Gbytes). More detail is provided in the progress reporting during alignment.

Improved alignment when the time between images is large (> 25 seconds). Fixed two errors that might cause crashes under rare circumstances.

- Added compensation for the color shift with dark frame subtraction when using cameras with a strong color cast to the dark frames. - Improved image classification when there are strong bursts of light in some light frames such as a car driving through the scene illuminating trees. - Improved image alignment in cases of low contrast or small areas of sky (e.g., gaps through trees or bridges). This improvement comes at the cost of increased time to align images with low contrast (e.g., fog, haze or very bright sky) or few stars (less than 100 visible). In extreme cases the time to align the images can increase by a factors of as much as 5. This cost is likely worth it as it can make the difference between an unusable image and a usable image. In the typical case there is no change in run time.

- Fixed a problem in the image classifier that would cause some light frames with large bright areas to be classified as dark.

- Improvements to the classification of light and dark frames based on feedback and samples from users. - Changed the size of the table used to view/correct the classification of images so that it was not exactly 6 rows tall. Because it was exactly 6 rows tall, it was easy for the user to not know that there was a 7th (or 8th...) row to check or correct. - The "Make" tag has been removed from the EXIF information to try to work around a bug in Affinity Photo. The information from the "Make" tag is embedded in the "Description" tag that is added by SLS. - Fixed a problem where it was possible to cause a crash by failing to load any images. - Changes to some error and warning messages to try and improve clarity. - Other bug fixes.

- Added ability to make and use master flat-field frames. - Better classification of light, dark and flat-field frames with fall back to manual classification. - Better handling of pre-made masks, in particular a file saved from Starry Landscape Stacker with a mask can be used as a mask in a later invocation of Starry Landscape Stacker. - More accurate alignment in a range of difficult cases. - Faster alignment in general but particularly noticeable when when the time between images or total time between first and last image is large. - Reduced memory usage during alignment. - More thorough checking of input files for consistency and correctness. - Better progress indication. - Bug fixes.

Added a popup menu that appears at the "Adjust Stars" stage that allows the user to select from 4 densities of red dots, from "Many dots" to "No dots". The red dots represent automatically detected stars. By choosing the best dot density the time spent hand-editing the red dots or the sky mask can be significantly reduced. Changed controls for brush sizes to make it easier to control small brush sizes without using the "[" and "]" keys. This is particularly useful for users who do not have "[" and "]" keys on their keyboard. Fixed some issues with consistency of brush size when zooming in and out. Fixed an error that would cause a crash when attempting to align some images that are difficult to align. Fixed a problem where undo did not behave as expected after clicking on "Adjust Sky".