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Messages - drmikevt

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General / Re: Batch Preprocess fails in integration step
« on: 2017 August 02 06:42:44 »
Have you ever had a successful integration using files in the Dropbox folder?  Have you tried moving the files out of the Dropbox folder?  Maybe Dropbox itself is the offending application....? 

Might be worth a try.... no idea if this will help.


I think the problem is that you are asking questions that you can answer yourself by looking at the associated documentation within in the program.  Check out chapter 3.11 of the Histogram Transformation documentation.  You can see it by clicking the 'browse documentation' button on the bottom bar of the process window. 

General / Re: Question on Creating Masks
« on: 2017 July 23 20:27:19 »
Most likely, things are happening correctly - they just look different then you expect.  When you say, "I just get a common curve", are you referring to the top graph in the Hist. Trans. window?  A normal looking curve would be expected there because that is what the result will look like.  Do this:
Select your linear image so that the top bar is blue. 
Hit the 'auto-stretch' button on the STF process window
Drag the triangle icon from the STF window onto the bottom bar of Hist. Trans.
Now drag the triangle from Hist Trans onto your image - don't worry about what the graphs in Hist Trans look like.
Your image should now be totally white (more or less).
Hit the reset button (the one on the bottom all the way to the right) on the STF process and your image should now be non-linear and look the same as if auto-stretched. 

Let us know if that works

Gallery / Re: NGC 7822 / Ced 214
« on: 2017 July 23 07:01:16 »
Another reprocessing.   Certainly, there are issues, but the purpose was to work on star removal, dynamic compression and color balance/hue.  Star were removed for the SHO images but added back with a synthesized Lum.

I also have sometimes struggled with 'What is the correct background?', esp in busy images.  Often, I will create 3-5 previews in different areas and run each through Background Neutralization to see which one yields the most neutral result.  Sometimes, the best results are found by taking those 3-5 previews and using the Preview Aggregator script to, well, aggregate them and use then use that resultant image as the background.

I don't know if this is overthinking or not, but sometimes the images are quite different in terms of neutral tone.


Gallery / Re: Moon
« on: 2017 July 16 21:02:40 »
+1 to everything above - please share!

Gallery / Re: NGC 6823 HaSHO
« on: 2017 July 14 15:55:08 »
What did you do to go from the 'neon' one to the last one?  Don't be afraid to be detailed.

General / Re: Process JunoCam Raw with PI?
« on: 2017 July 13 13:06:32 »
Yes - this processing took about 2 minutes.  I'm sure others could do a better job - I have no experience at all with planetary data.  How do you color calibrate, anyway?  I've just used curves and a few contrast enhancement processes.

General / Re: Question about Subframe selector script...
« on: 2017 July 13 08:39:36 »
Yes, it is a weighting expression.  However, perhaps we should note that the author of Image Integration (perhaps he's biased) feels strongly that the default parameters are well designed to create the highest SNR image possible from the data, and that individual weighting of subframes does not yield much to any benefit.  Here is a copy/paste from the 'tips' section of the documentation of ImageIntegration:

Unless you have a strong reason to do otherwise, use the noise evaluation weighting method. In all of our tests this method consistently leads to the highest SNR improvement in the integrated images.

I use SFS to remove the outliers in FWHM, Eccentricity and SNR.  I used to weight all the images, but abandoned that approach after experimentation showed me it made no difference.  You will get a bigger and better impact on SNR by carefully tweaking the high and low pixel rejection parameters, to only allow rejection of the truly problematic pixels and nothing else.  Certainly there is a lot on the web about weighting images, and some people have proposed some pretty complicated expressions, but - has anyone shown it actually makes a difference if the subs themselves are well culled through? 


General / Re: Process JunoCam Raw with PI?
« on: 2017 July 13 05:13:51 »
I looks like it is already separated into R,G,B images.  Combing them with Channel Combine seems to work well, and then applying curves gets you some nice color.  Cool!

General / Re: Process JunoCam Raw with PI?
« on: 2017 July 13 05:06:17 »
I'm not quite sure what I'm looking at yet, but here is the link to the raw data:

Gallery / Re: NGC 6823 HaSHO
« on: 2017 July 12 08:11:01 »
Very nice - I like how 'natural' your image looks for a NB image. 

Gallery / Re: NGC 7822 / Ced 214
« on: 2017 July 12 08:04:10 »
Yes, I have been doing a lot of thinking about how to represent NB data.  More or less, you have a choice between trying to represent the data in the most 'true/scientifc' way, in order to show how the data from different filters differ, or you choose to make a pretty picture and decide to let go of differential color information. 

But, this assumes we agree on what a pretty picture is.  As I've said, I think the first pic is quite nice and I like the full range of colors (despite it having a number of sig. processing issues).  However, I'm also excited that I've figured out how to get to the gold/blue palette that is so popular (and pretty). 

I should say that I think I have noticed that SHO to RGB mapping goes best (for me) when there is very little data manipulation prior, which is to say there is no attempt to match the channel intensity, and the combination is in the linear stage.  You just deal with the raw data (assuming, of course, that you have reasonable data from all 3 filters).  However, when going for the blue/gold palette, it seems quite important to first stretch the 3 channels to a similar level before combining, and then I've seen the best results (so far) with the SHO-AIP script using about 50/50 S/Ha for red, 50/50 Ha/O for green and 120% for O3 in blue (with a pre-made, combined Lum) (and then following that with various Color Masked curves).  My workflow is evolving quickly and I hope to post instructions for achieving blue/gold using only PI soon.


Gallery / Re: NGC 7822 / Ced 214
« on: 2017 July 09 19:34:58 »
Here is a complete re-working of the data using quasi tone-maps and the SHO-AIP script followed by Color Mask and non-masked curves.  I was shooting for the elusive blue/gold palette which seems to be a struggle for most without using that other program.  Start to finish processing in PI.   Some of the stars have a bit funky and I plan to eventually replace them with RBG stars.  The down-scaled version below is a bit darker than the larger one on A-bin,


General / PI takes minutes to quit on Mac
« on: 2017 July 08 07:03:48 »
This came up in a workshop I went to a little while ago.  Most Mac users there had noticed that PI can take multiple minutes to quit.  The application seems to quit, but the little dot in the Dock stays active for quite a while, then eventually quits entirely. 

I can only assume this has come up before?   Is this a known issue or is there a fix?


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