Show Posts

This section allows you to view all posts made by this member. Note that you can only see posts made in areas you currently have access to.


Topics - astrodoc71

Pages: [1] 2 3
1
General / New installation question
« on: 2019 October 01 14:09:03 »
Question is that by uninstalling the previous version, which I believe is necessary every time you install a new package (?), I will lose all of the scripts and manual additions (e.g. starnet etc) that I have added since the last version and will then have to locate and reinstall all of that? Is there any way to avoid that?
Thanks
Dave

2
General / Error loading multichannel scripts
« on: 2019 March 30 16:29:29 »
Must be something basic I am missing. Tried opening any of the multichannel scripts and I get these file not found errors. Scripts have been placed in the usual script folder and are listed properly in the multichannel synthesis drop down
Thanks
Dave

3
General / Narrowband scripts in 1.8.06?
« on: 2019 February 21 17:55:15 »
I only see the NBRGB combination script under utilities in the current PI version. What happened to HA RVB and the SHO scripts?
Thanks
Dave

4
General / Image statistics process
« on: 2019 February 02 06:20:20 »
I'm using the image statistics process to measure percent saturation of a spectrum by looking at maximum ADU for the image (see attached). This is a raw image, no dark subtraction. Since there is no calibration at all, is this going to be an inaccurate measure if there are hot pixels present? Or is this process not really affected by hot pixels?
Thanks
Dave

5
General / "Risky Temporary Folder" message
« on: 2019 January 25 05:28:52 »
I just installed the new 1.8.6 version and get this message on opening the program which I have not seen before. No idea if I need to do anything about it or not.
Thanks
Dave

6
General / Median eccentricity
« on: 2018 April 01 08:40:52 »
Just a general question on what values, in the image analysis scripts that measure this, mean more "roundness". I'm pretty sure that lower values e.g. 0.3-0.5 are "better" but just trying to understand the concept better.
Thanks
Dave

7
General / FWHMeccentricity script question
« on: 2018 February 10 07:24:11 »
Can this script confuse hot pixels with stars in uncalibrated images? Is it better to dark subtract first before measuring? I noticed an unusually low number for average FWHM and when I checked individual stars with the PSF process it was much different (way higher number). Is there another process you can use to check individual stars FWHM?
Thanks
Dave

8
General / Difficulty removing bad column
« on: 2017 April 04 06:48:13 »
Strange issue with bad column removal. I noticed it in the final image. Not glaringly obvious but it was there. So I went back and sure enough it was very subtle but present in the supposedly calibrated images. I was using batch preprocessing. Checked all of the dark masters and the bad column is most definitely present so not sure why it is not being completely removed. However, when I checked "optimize dark frames" it did improve. I haven't checked integration yet with the optimized images but I can still see the column very very faintly. Just wondering what else I can try
Thanks
Dave

9
General / Question on extract wavelet layers script
« on: 2016 January 05 16:33:37 »
Is there a way to recombine the layers after making adjustments to individual ones? Would that be just a pixel math operation adding them back and rescaling the result?
Thanks
Dave

10
General / donut disaster
« on: 2015 November 28 13:13:50 »
Just wondering if anyone has discovered a way to eliminate dust donuts after the fact, meaning after a failed calibration. I understand the right answer is to recalibrate, take new flats etc and I am working on that but curious if there is a way to fix this afterward. Unfortunately DBE does not fix them. I have tried a million permutations and combinations. Interestingly the closest I have come to fixing it is in the non-linear stage, extracting individual layers and doing pixel math on a larger structure layer, then recombining. Problem is that data is clipped with this approach. Unfortunately I believe that in my frustration I inadvertently deleted the file so I don't have it to post, but if anyone has discovered a general approach to the problem that has been effective for you I would like to know what that is.
Thanks
Dave

11
General / testing flats
« on: 2015 June 06 04:30:42 »
Unfortunately my flats need to be adjusted to work properly for this particular data setIs there a way to test your changes on a single image or some subset without going through the whole calibration process?
Thanks
Dave

12
General / Comet processing advice for longer focus image
« on: 2015 January 17 15:22:54 »
The problem is that the integrated image aligned on the stars results in a fairly bad comet smear since at longer focus there is much more movement of the comet during a 1 hour total integration time. I have no idea how to get rid of this artifact as it covers almost an entire quadrant of the image. So I need to figure out how to prepare a background star image to be used in this particular case where there is excessive comet motion at longer focus.
Thanks
Dave

13
General / Using process console info to compare integration methods
« on: 2014 December 26 16:57:08 »
Let's say you integrate with linear fit and windsorized sigma and compare. In the process console there is this parameter "SNR estimates". If WSC yields a smaller number than linear fit then that result has better signal to noise? Or is this an oversimplification?
Thanks
Dave

14
General / Using pixel math for uneven sky background
« on: 2014 June 21 15:04:32 »
I would think it would be fairly straightforward to assign one value somehow to all the background pixels? I do have light pollution where I am at and despite my best efforts with DBE, ABE etc I cannot always get rid of all the gradients. I have gotten pretty good at eliminating the color cast but there is frequently residual uneven illumination that remains.
Thanks
Dave

15
General / Preprocessing script warning regarding master darks
« on: 2014 June 01 14:08:34 »
When I run the script I get the purple message: Warning: no correlation between master dark and target frames. The script runs fine and the files appear to be adequately calibrated. Not sure what the warning is all about. Doesn't seem to matter whether the dark frames are matched in time and temperature or not. The message still appears
Thanks
Dave

Pages: [1] 2 3