www.Starry-Night.nl | Wang | Activity

Wang started the topic Thoughts about multiplicative+additive+nonlinear normalization in the forum Astro Pixel Processor Beta

Sat, 13 May 2017 06:02:52 +0200

Hi,

We talked about this in the previous thread. I think it’s better to open a new thread for this topic. The method I am going to suggest was once used in my old image processing. So it should work to certain degree.

The idea is to identify overlapping regions between two registered frames. Suppose the pixel brightness in one frame is I1(x,y),…[Read more]

Wang replied to the topic Error: java.lang.NegativeArraySizeException in the forum Astro Pixel Processor Beta

Thu, 11 May 2017 04:47:03 +0200

Hi Mabula,

Thanks for the reply. It is very fun to try APP and I see lot of potential.

I know that my Milky Way panorama is very challenging. At this moment, no any other programs can go as far as APP has. So even though the results above are not good enough yet, APP has already been far more successful than any other program. It is rea…[Read more]

Wang replied to the topic Bug report: crash after switching between screens in the forum Astro Pixel Processor Beta

Thu, 11 May 2017 04:16:44 +0200

Does APP automatically send you (or save locally) a crash report every time it is crashed or forced to terminate? It should be useful.

Wang replied to the topic Error: java.lang.NegativeArraySizeException in the forum Astro Pixel Processor Beta

Tue, 09 May 2017 15:08:55 +0200

More attempt. This time, the brightness/contrast different between panels seem to reduced. I had used the advanced and multiply-scale options for normalization. I am not sure whether this combination of parameters is responsible for the improvement.

On the other hand, the registration is still terribly wrong. I increased the detected stars to…[Read more]

Wang replied to the topic Bug report: crash after switching between screens in the forum Astro Pixel Processor Beta

Tue, 09 May 2017 04:41:27 +0200

Sorry. Further tests show that it has nothing to do with moving APP’s window from one monitor to the other. Even if it stays in the same window, just shutting down the other one can trigger a crash.

Wang started the topic Bug report: crash after switching between screens in the forum Astro Pixel Processor Beta

Tue, 09 May 2017 04:28:36 +0200

I have two monitors connected to my Mac. The two have different resolutions. Dragging APP between the two monitors is OK and would not cause troubles.

On the other hand, APP would crash when I turn one monitor (the one with APP) off and the system forces APP to move to the monitor that’s on. The forced movement between monitors works totally fine…[Read more]

Wang replied to the topic Error: java.lang.NegativeArraySizeException in the forum Astro Pixel Processor Beta

Mon, 08 May 2017 15:43:20 +0200

Hi Mabula,

Thank you. The new system warning should be very useful. 700 MP is already slightly larger than the largest mosaic that I had ever built:

http://www.astrobin.com/250543/?nc=user

Is 32bit floating point the internal data format for APP? Does relaxing it to 16bit floating point allow for 1.4 GP images without significant rebuilt of…[Read more]

Wang replied to the topic Error: java.lang.NegativeArraySizeException in the forum Astro Pixel Processor

Mon, 08 May 2017 03:43:20 +0200

A new kind of error message pops up. This time I tried to mosaic a subset of panels to see if I can avoid the out of memory error. Then I saw this new error message soon after I initiated the stacking procedure.

Wang replied to the topic Error: java.lang.NegativeArraySizeException in the forum Astro Pixel Processor

Mon, 08 May 2017 03:28:34 +0200

More to report.

This time I used a different computer and allocated 80 GB of RAM to APP. It still shows an out of memory error. What’s funny is that I once successfully stitched all the panels together using a computer with just 16 GB of RAM. Then I couldn’t reproduce the success on the same computer and on the more RAM-rich computer: al…[Read more]

Wang replied to the topic Error: java.lang.NegativeArraySizeException in the forum Astro Pixel Processor Beta

Sun, 07 May 2017 17:15:24 +0200

Looks like Registar can deal with both additive and multiplicative terms simultaneously. Unfortunately I have no idea how that was achieved. It can even handle images that are not linear. (It was produced during the film era.) So it may be doing more than simple multiplicative+additive calculations.

In my own data processing for large t…[Read more]

Wang replied to the topic Error: java.lang.NegativeArraySizeException in the forum Astro Pixel Processor Beta

Sun, 07 May 2017 16:30:57 +0200

Ideally, we will need both additive and multiplicative. As you mentioned, the sky brightness can change with time during the night. So an additive term is needed. At the same time, a multiplicative term is also needed to account for the change in sky transparency, even if the photographer did not mix different ISO. And of course, in add…[Read more]

Wang replied to the topic Error: java.lang.NegativeArraySizeException in the forum Astro Pixel Processor Beta

Sun, 07 May 2017 14:38:04 +0200

I am still a bit confused by the difference between add-scale and multiply-scale. Let’s say the images were taken under different sky brightness (strong light pollution and less light pollution). So obviously there is a need for an additive term. Also, for some reason, the images were taken with different ISO. So a multiplicative term is als…[Read more]

Wang replied to the topic Error: java.lang.NegativeArraySizeException in the forum Astro Pixel Processor Beta

Sun, 07 May 2017 13:01:44 +0200

Looks like equirectangular is more suitable for a Milky Way pano. I always hate to see a rectilinear projection. The distortion is just too severe.

The 2pi sky pano just cover half of the whole sky, or a hemisphere. Looks to me a fisheye or a stereographic projection would be more suitable.

Another question here. In the normalization page, one…[Read more]

Wang replied to the topic Error: java.lang.NegativeArraySizeException in the forum Astro Pixel Processor Beta

Sun, 07 May 2017 04:29:04 +0200

For the orientation, now I can see why the image in the previous screen shot is tilted. Among all the panels, one is tilted relative to the Galactic plane, and that one happened to be picked by APP as the reference.

My OS is MacOS 10.10.5. The machine is a 3.4GHz i7 iMac with 16GB of RAM. The OS and apps are all stored in a 1TB-SSD*2 RAID0 e…[Read more]

Wang replied to the topic Error: java.lang.NegativeArraySizeException in the forum Astro Pixel Processor Beta

Sat, 06 May 2017 17:01:25 +0200

Hi Mabula,

I will try with your recommended parameters tomorrow. Here are a few additional related and unrelated points.

1. I believe I used equirectangularProjection instead of the standard rectlinearProjection. I might be wrong.

2. I also did try a small subset of the panels to start with. APP can process them successfully. Please see the…[Read more]

Wang replied to the topic Error: java.lang.NegativeArraySizeException in the forum Astro Pixel Processor

Sat, 06 May 2017 15:01:52 +0200

This is the full screenshot when that error happened. The composition mode is indeed set to full. And yes, the mosaic is larger than 120 deg. It’s a 360-deg pano of the Milky Way.

Wang started the topic Error: java.lang.NegativeArraySizeException in the forum Astro Pixel Processor

Sat, 06 May 2017 11:05:18 +0200

Hi,

I am trying to create a mosaic. After the registration stage, I saw an error message during the image stacking. Please see that attached image.

Unfortunately my experience with APP is still very limited. This is pretty much the first time I use it. I can’t guess what might have caused this.

Cheers,

Wei-Hao

Wang became a registered member

Wed, 08 Mar 2017 23:32:23 +0100

Wang joined the group

Wed, 08 Mar 2017 16:09:14 +0100