NGC Thumbnails

John S. myxlflik at hotmail.com
Mon Apr 17 16:44:18 UTC 2017


Did anyone have any further input on this?  Is it worth pursuing and adding to Kstars?


________________________________
From: John S. <myxlflik at hotmail.com>
Sent: Saturday, April 15, 2017 11:00 AM
To: Hans
Cc: KStars Development Mailing List
Subject: Re: NGC Thumbnails


Here is a link to the current NGC file tarball and the rudimentary install and removal scripts.  This has only been tested on Linux Mint, but suspect it will be fine on all versions:

https://1drv.ms/u/s!AnSnRFrNRtfXviEYxBIM2pNlmuc6


Here is a link to the current IC file tarball.  Same caveats as the NGC file:

https://1drv.ms/u/s!AnSnRFrNRtfXviLmrzlp6Ru6N7KZ


The images are all of the DSS2R (Red Plate) survey only.  There is an ability to pull data into RGB using the DSS2R, DSS and DSS2B surveys (or really any other combination for that matter).  I have found that in nearly all cases, the colors needed subsequent adjustment in order to make the images look palatable.  I honestly felt the red channel ones and gray scale worked out just find overall.  I know there are some outright bad images in there and I haven't had the time or inclination to weed through the 13,000 objects I pulled to clean it up as of yet.  I can certainly do it, but it would largely depend on how strongly this group felt about it's inclusion.  I agree it should be an add-on package and not part of the base install.  We will need to make sure to credit the sources of the images as well.


One thing we may need to consider is directory management.  Downloading all of these images puts 13,000+ files in the $HOME/.local/share/kstars directory.  That's a pretty good chunk of files for a single directory.  I may make sense to compile these into some sort of database file or put them in a directory structure.  I am not a developer though and have NO skill when it comes to that aspect of this project.


John

________________________________
From: John S. <myxlflik at hotmail.com>
Sent: Saturday, April 15, 2017 10:15 AM
To: Hans
Cc: KStars Development Mailing List
Subject: Re: NGC Thumbnails

I started this project for my own personal gratification. I personally don't mind that some of the objects are subpar quality. Most of those objects are very interesting to me anyway. However, I would like to make sure that it meets certain quality levels. I am open to input for how to rectify the situation. I believe the limits of the survey itself will limit the outlet quality though. If you want I'll post the links to the two tarballs for the NGC and IC objects and you can download them a try for yourself.

John

> On Apr 15, 2017, at 9:02 AM, Hans <hans at lambermont.dyndns.org> wrote:
>
> Agreed, this is something very nice to have. And it is tedious work too.  For
> images that don't look too good I expect we'll even get negative remarks, but
> that should not inhibit this project. To me having a skimpy image is far better
> than no image at all.
>
> Is the idea to have an image library or to dynamically download them on demand ?
>
> -- Hans
>
> Jasem Mutlaq wrote on 20170415:
>
>> I'm attaching a few examples so you can see why we can't use them as is in
>> KStars.
>>
>>> On Sat, Apr 15, 2017 at 9:43 AM, Akarsh Simha <akarshsimha at gmail.com> wrote:
>>>
>>> Hi
>>>
>>> This is something very nice to have!
>>>
>>> A caveat to consider is the licensing for DSS imagery. They are not
>>> available for commercial use, so we must ship this as an add-on through
>>> KNewStuff ("Get New Data")
>>>
>>> Other sources of images are SDSS, the Hubble Legacy Archive (hla.stsci.edu)
>>> and the recently released PanStarrs 1 survey. I think the PanStarrs 1
>>> survey has a large sky coverage (possibly even all sky -- I haven't
>>> checked). SDSS has a somewhat small footprint, and the Hubble only has
>>> objects of interest.
>>>
>>> I didn't quite get what the problem involved is. The DSS is made from
>>> digitizing scanned plates mostly from the Palomar Observatory and UKSTU
>>> telescope. The result is that many plates have artefacts, and they are
>>> completely uncalibrated. Planetary nebulae and bright emission nebulae tend
>>> to be overexposed. There is no way around these problems other than going
>>> to other surveys.
>>>
>>> Regards
>>> Akarsh
>>>
>>>
>>
>>
>> --
>> Best Regards,
>> Jasem Mutlaq
>
>
>
>
>
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mail.kde.org/pipermail/kstars-devel/attachments/20170417/11e0a28a/attachment.html>


More information about the Kstars-devel mailing list