What's in store for SLL v 3.3?

[Ain Soph Aur]

Hi Paul. What's in store for SLL v 3.3  Inquiring minds want to know 

[Paul81]

A couple of minor updates are coming in V3.3:

1. Night Vision mode - you can enable / disable dark room style colours for the user interface and can also select the video display to do the same if required (need to fix a rendering issue on OSX)
2. Mirror the display image horizontally / vertically to correct for telescope optics
3. Some performance enhancements, both in display and stacking. For example an image that took ~1.2s to stack on my machine is now ~0.4s.
4. I want to get to the bottom of this 'dark frame bug' - still trying to replicate it - if I have no success will release and continue investigation.

 

Beyond that the other things I am currently working on are the algorithms for automatic display stretching and colour balance. That would be for a V4.0 release though as its a 'major' capability update.

Paul

[jimthompson]

I wonder if it is okay to make requests wrt software features?  I have a few ideas but don't know how major an effort they would be to implement.

1.  User defined gamma:  Very early versions of LodestarLive had an extra slider to adjust gamma, but that has since been replaced by the three histogram scaling presets (linear, arcsinh & x^0.25).  Although the presets work well, I still miss being able to adjust gamma (or "grey point") manually.  On really dim objects it would be nice to push the gamma even more than what the presets allow for.  As an example the white/grey/black set point sliders on the histogram in the Infinity software works very nicely.

2.  Sharpening tools:  I can recall asking about this in the past (I just don't remember who I asked!) but am yet to see it implemented in most EAA software.  In the past I have passed my live feed through VirtualDub using its screen capture tool, then applied sharpening filters in VD.  I especially like "warpsharp" and "unsharp mask".  The warpsharp algorithm is out there in the opensource world.  I like it as it tightens up edges and makes stars less bloated, and it reduces the visibility of noise.  Unsharp mask is a classic detail enhancement tool that can greatly increase contrast in the image.  If not set correctly it will also enhance noise, so it works better on a stacked image with low noise.  I will try to generate some example images when I get home from work to show the impact of applying these two filters.  Personally I think sharpening would add a great capability for live observing.

3.  Zoom in on histogram:  When using the current histogram I sometimes find it difficult to see what is going on with the histogram since the whole 16bits of the image is being displayed, resulting in the image data occupying only a small part of the histogram.  Is it possible to instead display just the part of the histogram between the white point and black point, or perhaps a little bit on either side of these points?  This would in effect zoom in on just the image data that is presently on the screen.  Perhaps it could be an option, to choose what scaling to use for the histogram plot?

Thank you for considering my ideas.  I appreciate your hard work!

Best Regards,

Jim T.

[jimthompson]

I have put together some image comparisons to try to demonstrate the impact of sharpening tools.  I used VirtualDub and its built in Unsharp Mask and Warpsharp tools in particular.  I have gone light on the sharpening settings to have a minimum of artifacts but still see a noticeable improvement in the image.  A lot more sharpening is possible using these same tools if you don't mind the increase in noise or other artifacts.

https://www.flickr.com/photos/abbeyroadobservatory/albums/72157675420188260

I find Warpsharp works well on nebulae as it shrinks the size of stars and smooths out the remaining noise if there is any.  This leaves the nebulosity itself more pronounced and easier to see.  Unsharp mask works well on scenes already having high contrast such as globular clusters, or on images with low noise (ie. large number of stacked frames).  It is tricky to use however and not have noise overly accentuated as well.  For very soft (blurry) images, such as what you tend to get when you stack images from a small sensor or at a long focal length, you can apply Warpsharp to tighten everything up then apply Unsharp Mask on top to further enhance detail.

For certain sharpening is a matter of personal preference, but I think it is a very important tool to have.

cheers,

Jim T.

p.s.  Another SLL improvement that I forgot to mention is fixing the red bleeding artifact around bright stars and yellow image tinge when using the Ultrastar C (see attached image)

[HiloDon]

Hi Paul,

Jim's image above reminded me about the green stars that appear when using the DPR tool both with the Ultrastar and Lodestar.  It's works great, except for the green stars.  Hope you can improve that as well in the next update.

Your efforts are well appreciated and everyone I teach loves Starlight Live.

Thanks,

Don

[Ain Soph Aur]

This is an awesome thread if I may say so myself.

I am working on the Astronomical League Flat Galaxies and ARP programs using SLL, and I suddenly realized how nice it would be if SLL offered an inverted display option. This, along with the possible 'auto-stretch' feature mentioned by Paul for 4.0, would be very nice!

[Ain Soph Aur]

Reading Jim's last post more closely, thumbs up about the red bloat. Since I strictly use multi-spectrum for color images, I have spent lots of time trying to minimize this with the best results with 5-10% less integration time on red. That does help some on the red bloat, but changes the star colors. I am using Astrodon filters, and per their web site the RGB filters should be very balanced on 1:1:1 exposures.

[Paul81]

I must look into the DPR green stars at some point :-)

With regards to sharpening, I am planning on adding a new tab 'Enhancements' which primarily has wavelet based denoise and sharpen controls. Ultimately this will replace the filters drop-down on the stacking tab (which is something I think doesn't really get used?). I can also add an invert there too - thats a simple one to implement in comparison!

[Dom543]

We were taught that kids, who wish fewer gifts from Santa receive more.

But since Paul himself said that he is working on night mode skins, I wish that there were at least two different such skins. Or one of their components could be user selectable. The other night I was running three separate versions of StarlightLive simultanously with three different cameras. It would have been nice to have some visual cue to indicate which camera's window I saw in the foreground. Even just a colored dot in the title bar would be sufficient. Anything simpler than going to the Exposure tab and trying to remember which camera corresponds to PID 0189.

Thanks,  --Dom

[Robrj]

Dom,

I can't recall for certain without it in front of me but if I remember correctly, when you set the name of the object (for file export) it contains that name in the title bar of the window.   I noticed that when I was trying to do the screen capture method with Stalight Live.  To grab that window, Astrotortilla has to match the name shown in the title bar (or you can use wild cards).   So if you set that at the beginning of your capture, it could be set to distinguish which is which (e.g. target name = X2 M51).

Then you can hover your mouse over the taskbar icon of running SLLs and see the titles for each window.

[Dom543]

Rob,

Thank you, you are right. In my particular case, I had three telephoto lenses on a cross bar aiming at the same object and I was also swapping three filters between the three cameras in the dark. So there were many things to pay attention to at the same time. Initially I tried to use the same file names for the same objects. Then later, as you see on the posted images, I did prefix each file name with the respective sensor's ICX number. I am not very good at paying attention to different things at the same time and I thought that it would have been nice to have some obvious visual cue to distinguish the windows. Even just different colored text in the title bar would have been sufficient.

But this may not be a typical case. I don't know how many people use several cameras at the same time. Even, if there is just one new night light skin, I could use that with one of the cameras and the old day time skin with my AstroRed windows theme for the other. Three cameras is probably more than what I would want to manage simultaneously with the short ~1 minute exposure times anyway.

Clear Skies!  --Dom

[Paul81]

I can add a simple command line parameter to add an extra string to the window title - this seems quite logical given the command line usage to enable multiple cameras at once. Its also fairly simple to add :-)

[Paul81]

I raised this as issue #2 and have added an additional command line parameter  '-prepend-title-text <TEXT>' to allow a user specified string to be prepended to the window title bar such that it allows multiple sessions of the application being used concurrently to be easier distinguished.

A test build with the new functionality is available - see https://bitbucket.org/Paul81/starlightlive/wiki/Home

Let me know how you get on!

[Bill S]

Very good! And I've learned a new word 'prepend'. I only knew 'append' until today.