Learning image processing

[JR]

I recently came across an article on remote imaging and was intrigued by the possibility of doing this for the enormous sum of £4 a month. Yes £4.

That figure turns out to be accurate, sort of, but nevertheless in a very meaningful way. Basically you can get data for two objects at a time, from a menu of preselected objects, taken by very expensive kit in Spain, Australia and Chile. The menu changes all the time and there's no shortage of choice. Once you have the data downloaded you can move on to select another two.

You get a limited amount of data each time however, usually two 600 second images in each narrowband Ha, Oiii and Sii, or broadband RGB. That makes a total of 60 minutes narrow band or 20 minutes RGB, but the data are calibrated with darks etc. Plus the images are taken under the best skies in the world.

The main issue is that weather and other factors prevent imaging so it can be weeks before you get what you specify, particularly from the Spanish telescopes, though it's easy enough to swap to another object from a more reliable site if you get fed up waiting.

I've found this a very useful way for getting real data to improve my use of processing packages. It's an interesting journey in itself, as the results from a given object can be made to vary enormously squared, and many images are of objects not visible from the UK. It gives a good leg up on the learning curve if someone wants to go from one shot colour to individual filter photography.

Here's an example of the downloaded Ha data (the major component) of part of NGC6188 known as the Fighting Dragons of Ara (constellation). It was taken with a Planewave CDK 24" Dall Kirkham f6.5 3974mm in Chile. These cost about $55,000 (probably plus delivery!). The data come in as more or less all black FITS frames. I have stretched a stack of two frames to show what's there. If you were to request the same narrowband data as a bespoke service it would cost you $120 (unit charges per hour vary by telescope).

My processing by combining Ha, Oiii and Sii may not be to your taste and it won't win any prizes for processing, but at least I have got to the point of moving on to improving the results, rather than wondering how to work that function or asking what on earth that does that one do. And I didn't spend $55,000 and end up depressed having wasted the money 😀

So far this resource has cost me £12 (cancel at any time) which I regard as a bargain. It's been particularly helpful following an investment in Pixinsight, that does everything and very well, but is initially totally impenetrable.

I can't say it's a rewarding activity defined strictly in astronomy terms, as you can't select the best field of view etc and you have no personal involvement getting the gear to work. On the other hand it's a way of imaging with no cold and tiring nights or outlay on equipment, struggling with heavy weights (the Planewave weighs 109kg if you can afford one), frustrating learning curves, or a house that looks like a badly organised astronomy shop, and that may appeal.

As I say, it's a boom for starting out on or homing processing skills. The data providers have many video tutorials covering a range of processing packages, a useful number of them included in the basic £4 a month.

The provider is Telescope Live. I have no connection or financial interest in the organisation. They tend to plague you with 'why not upgrade your subscription?', but a quick delete sorts that out.

[tcos...@gmail.com]

Hi James
Thanks for sharing this interesting post. I've seen adverts for Telescope Live but have not tried it out as I currently subscribe to iTelescope, another remote imaging provider. Strangely enough they've recently started offering data sets of well-known targets taken by professionals on their high-end kit for end user processing. It’s a great way of learning or honing one's image processing skills. The downside is that one doesn't really learn very much about the image taking process which for me is where more of the 'fun' lies. I always feel excitement being under a lovely starry sky and there is always a challenge deciding how one is going to image a target and the practicalities of doing so. That being said, using providers like Telescope Live is a very economical way of getting hold of good data to learn and create beautiful images, so you really can't knock it!
KR
Tim

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[William Bottaci]

I'm thinking this may interest school children, where they can't yet afford equipment, but can learn. William

On Sat, 25 Sept 2021 at 12:42, <tcos...@gmail.com> wrote:
Hi James
Thanks for sharing this interesting post. I've seen adverts for Telescope Live but have not tried it out as I currently subscribe to iTelescope, another remote imaging provider. Strangely enough they've recently started offering data sets of well-known targets taken by professionals on their high-end kit for end user processing. It’s a great way of learning or honing one's image processing skills. The downside is that one doesn't really learn very much about the image taking process which for me is where more of the 'fun' lies. I always feel excitement being under a lovely starry sky and there is always a challenge deciding how one is going to image a target and the practicalities of doing so. That being said, using providers like Telescope Live is a very economical way of getting hold of good data to learn and create beautiful images, so you really can't knock it!
KR
Tim

On Thu, 23 Sept 2021 at 15:56, 'JR' via croydonastro <croydo...@googlegroups.com> wrote:
I recently came across an article on remote imaging and was intrigued by the possibility of doing this for the enormous sum of £4 a month.  Yes £4.

That figure turns out to be accurate, sort of, but nevertheless in a very meaningful way.  Basically you can get data for two objects at a time, from a menu of preselected objects, taken by very expensive kit in Spain, Australia and Chile.  The menu changes all the time and there's no shortage of choice.  Once you have the data downloaded you can move on to select another two.

You get a limited amount of data each time however, usually two 600 second images in each narrowband Ha, Oiii and Sii, or broadband RGB.  That makes a total of 60 minutes narrow band or 20 minutes RGB, but the data are calibrated with darks etc.  Plus the images are taken under the best skies in the world.

The main issue is that weather and other factors prevent imaging so it can be weeks before you get what you specify, particularly from the Spanish telescopes, though it's easy enough to swap to another object from a more reliable site if you get fed up waiting.

I've found this a very useful way for getting real data to improve my use of processing packages.  It's an interesting journey in itself, as the results from a given object can be made to vary enormously squared, and many images are of objects not visible from the UK.  It gives a good leg up on the learning curve if someone wants to go from one shot colour to individual filter photography.

Here's an example of the downloaded Ha data (the major component) of part of NGC6188 known as the Fighting Dragons of Ara (constellation).  It was taken with a Planewave CDK 24" Dall Kirkham f6.5 3974mm in Chile. These cost about $55,000 (probably plus delivery!).  The data come in as more or less all black FITS frames.  I have stretched a stack of two frames to show what's there.  If you were to request the same narrowband data as a bespoke service it would cost you $120 (unit charges per hour vary by telescope).

My processing by combining Ha, Oiii and Sii may not be to your taste and it won't win any prizes for processing, but at least I have got to the point of moving on to improving the results, rather than wondering how to work that function or asking what on earth that does that one do.   And I didn't spend $55,000 and end up depressed having wasted the money :)

[JR]

I agree, armed with free software like Gimp if they can't access anything else, they could do a lot.

James

Sent from my iPad

On 29 Sep 2021, at 14:30, William Bottaci <w.bo...@gmail.com> wrote:



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