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jerryyyyy
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32-bit PixInsight? DOA?
      #5690536 - 02/20/13 10:06 AM

Have been looking at thius software and it seems promising, however it seems the 32-bit version is no longer supported?

I have tried to get on their forums but they do not seem to be too responsive to my attempts to sign up and get some real answers on this (A bad sign).

Good software? Any product support?


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Peter in Reno
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Re: 32-bit PixInsight? DOA? new [Re: jerryyyyy]
      #5690588 - 02/20/13 10:33 AM

PixInisght for 32 bit Windows is no longer supported, only 64 bits. Their algorithm requires lots of processing power that it was not worth continuing to use 32 bits. It took me several days to sign up for their forum. Once signed up, the support is fantastic. Also PixInisght is a fantastic software, you won't regret it.

Peter


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jerryyyyy
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Re: 32-bit PixInsight? DOA? new [Re: Peter in Reno]
      #5690639 - 02/20/13 11:06 AM

Thanks. I got into the forum. They never sent a notice.

My machine, a Dell M2400 precision workstation laptop has a fast dual processor and work through the calculations fine. I guess eventually I will go 64-bit by had a 64-bit laptop machine and there are a lot of programs that require use of the emulator for 32-bits that perform poorly.

Anyway, I tried to follow the first basic tutorial on YouTube:

PixInsight Processing Example: NGC 1808 LRGB (Part 1/2)

It worked on my own data until the Dynamic background Extraction where instead of using the actual correction calculated in the example they loaded some other data to correct and miraculously the gradients corrected. When I use my own calculated correction and execute it, nothing happens to the image. Is this just the degraded 32-bit version or what am I missing.


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Peter in Reno
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Re: 32-bit PixInsight? DOA? new [Re: jerryyyyy]
      #5690649 - 02/20/13 11:12 AM

Try this tutorial.

http://www.harrysastroshed.com/pixinsighthome.html

The DBE issue you are having should have nothing to do with 32 bits. I started at 32 bits two years ago and it was working fine. It may be operator error on your part. I like Harry's video tutorial better than PixInsight's.

Peter


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SL63 AMG
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Re: 32-bit PixInsight? DOA? new [Re: jerryyyyy]
      #5690676 - 02/20/13 11:29 AM

Quote:

My machine, a Dell M2400 precision workstation laptop has a fast dual processor and work through the calculations fine.




For small tasks, perhaps, but once you start doing things like deconvolution your processor probably won't handle the task very well.

I have an I7 x980 3.33Ghz 6 core 64bit processor with 12GB of RAM. Windows 7 see's 12 processors (Xeon) and when I run these routines I can see all processors running at nearly 100% utilization for several minutes.

I think 64bit processing is essential for programs like PixInsight.


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pfile
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Re: 32-bit PixInsight? DOA? new [Re: SL63 AMG]
      #5690688 - 02/20/13 11:36 AM

"they" is really one guy so give him a break if he can't fill forum registration orders in seconds.

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SL63 AMG
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Re: 32-bit PixInsight? DOA? new [Re: jerryyyyy]
      #5690711 - 02/20/13 11:53 AM

Quote:

It worked on my own data until the Dynamic background Extraction where instead of using the actual correction calculated in the example they loaded some other data to correct and miraculously the gradients corrected.




I also found this confusing in their video. Once you understand how PixInsight works, it becomes clear.

Basically, on the bottom left corner of every tool is a New Instance icon (arrow). Once you set parameters exactly how you want them for a given tool, you can drag this new instance icon and drop it in the process area located on the left hand side of the workspace and it will save all of the parameters you set for that tool. You can reuse those parameters any time by dragging the process icon back onto the tool or even directly to the image.

As far as DBE is concerned, I have found it works best when you increase the default sample size from 5 to around 15 and use more samples across all of the available sky background. I usually pick a value like 12-16 samples per row and let the program generate the samples. If there's too many, change the samples per row and regenerate or vice versa for too few samples.

You can use the forward and reverse buttons at the top of the tool to cycle through the samples more quickly than clicking on them. You need to scroll through them and delete any that fall onto nebulosity or your galaxy. Any that are on stars as can be seen by a group of black pixels, simply slide them off of the star so they only expose background sky. Keep in mind that for DBE to work correctly it is important that the samples only sample sky background.

That's the magic they did in the video. They had previously setup all the DBE parameters for NGC1808, set the samples where they wanted, saved the instance as a process icon and then later dragged that process icon back onto the DBE tool to set all the parameters and samples to their previously configured values. You can even set the process icon identifier name to something like DBE_NGC1808 so you can resuse it, for exmaple, on the luminance image. In fact, you can simple drag the process icon directly onto an image and it will execute the DBE tool on the image.

I watched this video a dozen times and there were several "tricks" they did that make it difficult for a new user to understand.

Another one that is likely to confuse you is when they use the Histogram Transformation tool to change the image from linear to non linear. They actually go out of the view of the user to disable STF (Screen Transfer Function) using the menu above the workspace and then they drop the STF new instance icon onto the Histogram Transformation tool, then drag the Histogram Transformation tool new instance icon to the darkened image (because they disable STF visualization).

I watched that many times before I figured out what they did "off screen".



Edited by SL63 AMG (02/22/13 03:08 AM)


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jerryyyyy
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Re: 32-bit PixInsight? DOA? new [Re: pfile]
      #5690723 - 02/20/13 11:57 AM

I'll be patient... looks like the software will do the job.

I have used Dell Precision Laptops for years for various purposes including a lot of C++ OpenGL programming. I believe the 64-bit with multiple processors will do the same jobs faster, but if you are in no hurry... Anyway, I am waiting for the next set of processors to come out and will get the I7 equivalent and now 64-bits... but they will not have the next generation out till later this year....

I seem to be having some problems just replicating the tutorials and the process runs quickly enough. Must be me, so will go over them again.

I am having trouble getting this Dynamic background Extraction to work. I have my own data with a messy backround to extract. Maxim and CS5 do it OK in about 27 steps...


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Peter in Reno
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Re: 32-bit PixInsight? DOA? new [Re: SL63 AMG]
      #5690732 - 02/20/13 12:02 PM

I do not like transferring STF to Histogram Transformation (HT). The "A" of STF is too aggressive to go from linear to non-linear. After I am done with processing up to just before I am ready to use HT, I disable STF so the linear image basically goes dark. Then I use baby steps in HT by first moving the mid-point slider to left, apply to the image. Then moving the left black point slider to the right until it meets the left edge of histogram graph. Repeat both steps until you are satisfied. Don't clip the black points and don't over stretch too much.

Peter

EDIT: When using HT, enable Preview so you can see the results in real time before applying to image.

Edited by Peter in Reno (02/20/13 12:07 PM)


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Peter in Reno
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Re: 32-bit PixInsight? DOA? new [Re: Peter in Reno]
      #5690755 - 02/20/13 12:14 PM

Jerry,

I had to watch both PixInsight's and Harry's video several times to understand what they were trying to say. It's the first time using PI is the hardest. Once you get the hang of PI interface, it becomes easier and very powerful. When I signed up for 45 day free trial, I learned it pretty quick thanks to video tutorials and I loved it that I bought after three days with 42 days left of free trial.

Peter


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pfile
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Re: 32-bit PixInsight? DOA? new [Re: Peter in Reno]
      #5690793 - 02/20/13 12:33 PM

by the way, learning to master DBE is one of the most nuanced things in pixinsight. Dave's advice is all good. you also have to watch out for 'bad' samples where the image is too bright or too dark for it to find the background. in this case you have to mess with the Tolerance parameter (increase it) and perhaps the shadows relaxation parameter until there are no red samples left (red = unusable sample).

also, as i mentioned in the PI forum don't forget to select a target image correction method. subtraction is what you want for sky gradients.

if you have black borders around your image after ImageIntegration, sometimes you need to crop them off before doing DBE. the borders are not actually black but very low pixel values and this throws off the statistical calculations that DBE does.

edit: every slider/box in every process has a tooltip. hover your mouse over the name of the slider or text entry box and you will get a description of what the slider or parameter box does.


Edited by pfile (02/20/13 12:35 PM)


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Peter in Reno
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Re: 32-bit PixInsight? DOA? new [Re: pfile]
      #5690899 - 02/20/13 01:27 PM

I have found that if it's difficult to differeniate between background and nebulousity coverage, I use Automatic Background Extractor (ABE) and does a nice job. I use default settings for ABE.

Peter


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Raginar
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Re: 32-bit PixInsight? DOA? new [Re: Peter in Reno]
      #5690970 - 02/20/13 02:00 PM

Everything Peter is saying. Is there some reason you can't use 64-bit PI? I've been using it on my 5 year old mac (Win7 and OSX) just fine for the last 6 months.

PI is definitely lacking on their documentation. Harry's examples above are very good; I'd sit down with the video on one screen and PI on another and just slowly go through each step as he did them. Then I just did each video.

Honestly, there isn't much tweaking required. It's just finding a flow that works and running with it.


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pfile
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Re: 32-bit PixInsight? DOA? new [Re: Raginar]
      #5691034 - 02/20/13 02:39 PM

oh - i should also say that due to UI quirks, changing the DBE parameters does not immediately update the color of the samples. if you want to see if you've taken care of the bad samples, click in the "sample size" box and without changing the number, click update. that will cause the sample colors to update.

and yeah, you really want to be running the 64-bit versions.


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neptun2
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Re: 32-bit PixInsight? DOA? new [Re: pfile]
      #5691317 - 02/20/13 04:48 PM

I do not use Pixinsight but can comment on the 32 and 64-bit versions of windows vista/7/8. In fact 32-bit programs work as good on 64-bit windows as on 32-bit. This is because 64-bit windows uses something called WoW (windows on windows) which is like running 32-but windows on top of the 64-bit core and drivers. This causes performance penalty but the usage of 64-bit core and drivers on 64-bit hardware in fact unlocks some more calculation power from the CPU itself which compensates for that. I have tested that and found that for 32-bit programs performance is the same and for 64-bit programs you will see only improvement. So if you have drivers for 64-bit windows for all your hardware (you can't use 32-bit drivers on 64-bit windows) do not worry to upgrade.

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WadeH237
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Re: 32-bit PixInsight? DOA? new [Re: pfile]
      #5691329 - 02/20/13 04:55 PM

I can't help but clarify a couple of misconceptions about 32 bit versus 64 bit.

First off, 64 bit is not faster than 32 bit. Actually, in many (or most) cases, 32 bit is a little faster on the same hardware. The benefit to 64 bits is that you have a much larger addressable memory space. This is a huge benefit to applications that manipulate large amounts of memory - like an image editor. So if you could compare 32 bit PixInsight side by side with 64 bit PixInsight, the 64 bit would get the job done quicker. But it's not a result of faster execution. It's a result of much more efficient memory usage.

Second, 32 bit software does not run in an emulation layer - at least not a software emulation layer. The CPU can run both 32 bit and 64 bit code natively.

I would guess that the PixInsight guys dropped 32 bit support because it makes their code cleaner, more efficient, and easier to maintain.

All that said, if you stick with PixInsight and learn to use it, you will not be sorry. It is absolutely first rate software with first rate support.

-Wade


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Charlie B
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Re: 32-bit PixInsight? DOA? new [Re: jerryyyyy]
      #5691337 - 02/20/13 05:02 PM

Quote:

I believe the 64-bit with multiple processors will do the same jobs faster, but if you are in no hurry...




Speed is not the biggest factor in using 64-bit processing, memory is. 32-bit processors can only address 4 GB of memory. 1GB of address space is reserved for IO processing, leaving only 3GB available for programs. I have both a 32-bit and a 64-bit laptop running Pixinsight. My biggest problem with the 32-bit processor is that the batch preprossing script crashes because it runs out of memory. When using image integration, I needed to reduce the buffer size to 8 MB and the stack size to 512 or 128, depending on the number of images being stacked, which did slow down the stacking. However, most processes run as fast with 32-bit processors if everything can fit in the available program memory.

My 64-bit laptop has 8 GB ram, all of which is available for programs.

Best regards,

Charlie B


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pfile
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Re: 32-bit PixInsight? DOA? new [Re: Charlie B]
      #5691454 - 02/20/13 06:14 PM

the 3GB limit is not IO processing, it's kernel address space, but yeah. i think most versions of win32 only allow 2GB of userland address space unless you compile the program with some special flags.

in theory the 64-bit machines should be slightly faster due to the addition of extra registers and the 64-bit native word width. in practice though the difference is small because the hardware has many more registers than are exposed in the ISA and juggles them behind the scenes.

plus with all this multithreading (hyperthreading) stuff the hardware has multiple register contexts. but you get that on the 32-bit versions as well.

rob


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Charlie B
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Re: 32-bit PixInsight? DOA? new [Re: pfile]
      #5691546 - 02/20/13 07:00 PM

Quote:

the 3GB limit is not IO processing



Not what I said. 1GB is reserved for memory mapped IO, leaving 3GB for programs.

Charlie B


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pfile
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Re: 32-bit PixInsight? DOA? new [Re: Charlie B]
      #5691689 - 02/20/13 08:23 PM

i meant "for IO processing"

but okay, have it your way. the kernel does not need any address space.


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jerryyyyy
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Re: 32-bit PixInsight? DOA? new [Re: pfile]
      #5691733 - 02/20/13 08:48 PM

Sorry to have set off a bit of a computing firestorm today.

So, bottom line is that I ran PI in 32-bit all day and I seem to have survived. It does peg the dual processors at 100%, but I never ran out of memory or used virtual memory. It does not seem to me to be worse than some processes I have had to run in Maxim.

However, on the Dynamic Background Extraction (DBE), there must be a lot of secret sauce involved here. I have some vignette images and it was very hard to get anywhere with them, so I cropped them and ran as TIFF files after cropping in CS5. This worked better, but would be nice to have some best practices for DBE like:

1. How many points are optimal?
2. Is there an optimal pattern?
3. Do you target noisy areas?
4. Can you run it multiple times without a problem?

Anyway, I am learning and probably will buy the software as I need all the help I can get.

PS I have an SSD on my computer so if I run into virtual memory it is hardly noticed...


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pfile
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Re: 32-bit PixInsight? DOA? new [Re: jerryyyyy]
      #5691756 - 02/20/13 08:59 PM

see my reply on the PI forum.

re: SSD that makes paging fast but you still have this hard 2GB/3GB limit that effectively forms a 'jail' for PI. it just can not allocate more memory past that point and memory intensive processes (like imageintegration) can fail.


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neptun2
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Re: 32-bit PixInsight? DOA? new [Re: pfile]
      #5692151 - 02/21/13 02:59 AM

One last reply to Wade's post - 64-bit windows uses emulation layer to run 32-bit applications. Here are more details:

http://en.wikipedia.org/wiki/WoW64

The CPU can execute both 32-bit and 64-bit code but not simultaneously so when you use 64-bit windows the core of the OS and drivers are 64-bit and CPU works in 64-bit mode so the WoW emulation layer is needed for 32-bit programs to run.


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WadeH237
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Re: 32-bit PixInsight? DOA? new [Re: neptun2]
      #5692471 - 02/21/13 10:20 AM

Wow64 is a set of 32 bit Windows libraries. Most of them are the same dlls that ship on the 32 bit only version of Windows. Wow64 also provides thunks for calls into the 64 bit kernel. These thunks are a translation layer to provide interoperability between user mode 32 bit code and 64 bit kernel code. The term "emulation" technically could describe this thunking layer because it makes 32 bit calls from user mode look like 64 bit calls to the kernel, and vice versa. It is not software emulation of the x86 instruction set, which is what was implied at the start of this thread.

On Itanium, Windows includes IA32Exec, which actually does software emulation of 32 bit x86. On this platform, 32 bit code does run slower than 64 bit code because of this emulation.

On 64 bit Intel CPUs other than Itanium, and on all 64 bit AMD CPUs, 32 bit code is executed natively. I have done substantial work with benchmarking code compiled for both 32 and 64 bits. In cases where there is no memory address advantage, 32 bit code frequently runs a few percentage points faster than 64 bit code on the same hardware for these CPUs.

My direct experience is with the previous generation of CPUs and compilers My expectation is that, at some point, we'll see parity in execution performance between 32 and 64 bits, or maybe a slight advantage to 64 bits, due to optimizations for 64 bit.

At the end of the day, though, the advantage to 64 bit is in memory addressing. Actual execution speed will remain very close between them, because they both run natively on the CPU.

And to tie this in some way to the topic, PixInsight benefits greatly from the 64 bit memory address space. It makes perfect sense to me that they would want to focus on that environment. Similar software, like CCDStack and Photoshop also run much better on 64 bit.


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jerryyyyy
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Re: 32-bit PixInsight? DOA? new [Re: WadeH237]
      #5692523 - 02/21/13 10:59 AM Attachment (9 downloads)

I agree with what Wade says and use the 64-bit machines in my lab for the severe data crunching that is memory intensive.

To return to image processing for a bit, I am having some problems determining if the crud I am seeing in my images recently is due to poor flats or skyglow. PixInsight has led me to try to make that distinction.

This shot is of M80 from early this AM. It is stacked in maxim using flats from Sky Flats Assistant. When I use these flats with narrow band images there is no crud at all. But with LRGB you see this and I think it is skyglow because I am in a Red Zone just south of San Francisco.

The screen shot is of my attempt to do DBE. I am pretty sure this is skyglow because it is not exactly centered on the image (the flats are) and that probably reflects some sort of gradiant across the sky.

Anyway, opinions cheerfully received and appreciated. I still need to clean up these images one way or another.

Finally, to reduce skuglow I am trying to use CCDComander to just take images as high as possible in the sky, i.e. only when obejcts is above 45 or 55 DEG. I had to take M80 at above 25 DEG since it is low in the sky... was the last object on my Messier list.


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pfile
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Re: 32-bit PixInsight? DOA? new [Re: jerryyyyy]
      #5692735 - 02/21/13 01:11 PM

have the flat subs been calibrated before making the master flat?

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Mike Wiles
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Re: 32-bit PixInsight? DOA? new [Re: jerryyyyy]
      #5692762 - 02/21/13 01:25 PM

Quote:

To return to image processing for a bit, I am having some problems determining if the crud I am seeing in my images recently is due to poor flats or skyglow. PixInsight has led me to try to make that distinction.

This shot is of M80 from early this AM. It is stacked in maxim using flats from Sky Flats Assistant. When I use these flats with narrow band images there is no crud at all. But with LRGB you see this and I think it is skyglow because I am in a Red Zone just south of San Francisco.

The screen shot is of my attempt to do DBE. I am pretty sure this is skyglow because it is not exactly centered on the image (the flats are) and that probably reflects some sort of gradiant across the sky.




When you apply the DBE process what correction method are you using? Division? or Subtraction? The gradient looks more like skyglow from light pollution - which would benefit from subtraction.

With DBE if you're trying to correct skyglow gradients, use subtraction.

If you're trying to correct vignetting or flat field issues - use division.

Mike


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jerryyyyy
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Re: 32-bit PixInsight? DOA? new [Re: pfile]
      #5693320 - 02/21/13 06:46 PM

Quote:

have the flat subs been calibrated before making the master flat?




Thanks for the comment but I do not know how to do this. I just use the standard settings in maxim for Callibration Settings. It does create a master flat. I am going to collect a fresh set tonight and start from scratch to make sure it is not a flats issue.


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jerryyyyy
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Re: 32-bit PixInsight? DOA? new [Re: Mike Wiles]
      #5693325 - 02/21/13 06:50 PM

Quote:

Quote:

To return to image processing for a bit, I am having some problems determining if the crud I am seeing in my images recently is due to poor flats or skyglow. PixInsight has led me to try to make that distinction.

This shot is of M80 from early this AM. It is stacked in maxim using flats from Sky Flats Assistant. When I use these flats with narrow band images there is no crud at all. But with LRGB you see this and I think it is skyglow because I am in a Red Zone just south of San Francisco.

The screen shot is of my attempt to do DBE. I am pretty sure this is skyglow because it is not exactly centered on the image (the flats are) and that probably reflects some sort of gradiant across the sky.

When you apply the DBE process what correction method are you using? Division? or Subtraction? The gradient looks more like skyglow from light pollution - which would benefit from subtraction.

With DBE if you're trying to correct skyglow gradients, use subtraction.

If you're trying to correct vignetting or flat field issues - use division.




I believe it is skyglow and am using substraction. The image does improve with substraction, but is not perfect. I seem to get as good if not better results in CS5 with Gradient Eliminator plug-in. I first tried division and that did little if anything I could see.

Mike




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pfile
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Re: 32-bit PixInsight? DOA? new [Re: jerryyyyy]
      #5693376 - 02/21/13 07:24 PM

Quote:

Quote:

have the flat subs been calibrated before making the master flat?




Thanks for the comment but I do not know how to do this. I just use the standard settings in maxim for Callibration Settings. It does create a master flat. I am going to collect a fresh set tonight and start from scratch to make sure it is not a flats issue.




i have never used maxim so i just don't know what those standard settings do.

flats have to be calibrated with at least bias frames. fixed offsets have to be removed from the flat since the flat will be multiplied by some factor 0..1 in order to properly remove the vignetting. if the bias is left in the flats this can mess up the computations.

you can also make dark flats which are darks that have the same exposure length as your flats. those will also contain the bias signal. with cooled CCDs the amount of thermal noise in a typical flat (2-10s or so) is so low that calibration with a master bias will suffice.


while DBE has extracted something that looks like a sky gradient, the original images really look to me like incorrect flat subtraction was done. you've really got to get your flats in order before trying to subtract sky gradients. you've got an artificial gradient in there that should be removable with good flats.


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jerryyyyy
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Re: 32-bit PixInsight? DOA? new [Re: pfile]
      #5695259 - 02/22/13 05:44 PM

Thanks for all the information, which I will process carefully. I am making progress. I am running the files also through Deep Sky Stacker to compare the results... have to say they look better than Maxim with the default settings. I am pretty sure it is skyglow and have various countermeasures for that... mostly careful cropping to minimize the gradients.

BTW, I am on travel for a week. Does anyone know if PixInsight works offline? Or do you have to be on the internet. Tried to process some files while on my lastr flight and got an error about connecting.

Does this go away with the paid copy?


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pfile
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Re: 32-bit PixInsight? DOA? new [Re: jerryyyyy]
      #5695368 - 02/22/13 06:42 PM

that message goes away with the paid copy for sure. i think the trial just wants to phone home to keep the trial from somehow going on forever...

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