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Should Exposure Length Define EAA?

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#1 glend

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Posted 16 April 2021 - 08:35 PM

You only have to look back through the EAA Image Gallery thread in this forum, to find many examples of what many would regard as traditional long sub capture, masquerading as EAA images. How do we define it? If your simply using Sharpcap as a substitute for SGP, or other traditional long sub applications, and avoiding additional processing steps, is this really EAA? 

Or maybe lazy traditional imaging?


Edited by glend, 16 April 2021 - 08:37 PM.


#2 SanjeevJoshi

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Posted 16 April 2021 - 11:40 PM

Long subs or long integration time?  Subs are driven by various factors, regardless of whether you are in EAA or anything else.  How do you define long sub?  Honestly, most EAA entusiasts do not use guiding, so by definition their subs are limited by Alt Az (which many have) or unguided EQ like my AVX - I am pushing it at 20 seconds, prefer 10 to 15 max.

 

 

Native C8 F10, the Stellina at 80mm F5 etc are two good examples of optical trains that benefit from longer integration times.   In my mind, they come closer to AP than the fact that I can use a 10S exposure on RASA 8 and 183 MC Pro and get a reasonable view in 10 frames.


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#3 GazingOli

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Posted 17 April 2021 - 12:26 AM

lazy traditional imaging?

I like this expression :)

 

In the German Astronomie.de/forum there is one guy who does +120 min live-stacks (postprocessing the images after). This might be considered lazy astro imaging, but it is not, because there are lots of things to do to get decent results.

 

For me the 'live' effect of EAA is based on capturing live-stacks in a relatively short time, like mikenoname does max 10 min in his videos. I do limit my observations to 50 to 100 live-stacked exposures per celestrial object (8 to 16 sec each). But I would not insist to make this a rule for EAA (in this forum).

 

I think the rules of this forum are clear enough and sufficient to define EAA!

 

CS.Oli


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#4 Noah4x4

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Posted 17 April 2021 - 12:51 AM

Yawn, not this again....

If folk want to talk about Astrophotography matters (such as categorising the length of subs into distinct definitions), can they please vacate this Forum and head into an Astrophotography Forum. We have defined EAA simply as camera aided observing with NO post processing and it's getting tedious for the subject of what is EAA to keep repeating. Yes, we might <save> an image as a memento, but the primary objective is not photography as a form of art. I don't even consider myself a photographer!
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#5 dcweaver

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Posted 17 April 2021 - 11:00 AM

The Admins and Mods have done a good job settling this.  I had my fun the other day in the last thread.  Time to move on.  The rule is easy... no post-pantsing.

   

https://www.cloudyni...ng-–-yet-again/



#6 DSO_Viewer

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Posted 17 April 2021 - 11:42 AM

Yawn, not this again....

If folk want to talk about Astrophotography matters (such as categorising the length of subs into distinct definitions), can they please vacate this Forum and head into an Astrophotography Forum. We have defined EAA simply as camera aided observing with NO post processing and it's getting tedious for the subject of what is EAA to keep repeating. Yes, we might <save> an image as a memento, but the primary objective is not photography as a form of art. I don't even consider myself a photographer!

I will 2nd it, this topic is now a big yawn! Why don't people here is type in their question in the search area of this forum rather than rehashing it over & over!!

 

Steve


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#7 nicknacknock

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Posted 19 April 2021 - 12:59 AM

As always, the answer lies in:

 

The forum description:

 

Electronically Assisted Astronomy (EAA) is the use of an analog or digital image capturing device in lieu of an eyepiece at the telescope. Here members can talk about the equipment used, share their observing experiences, and post sketches and images captured with EAA devices.

 

and

 

The forum guidelines:

 

This forum is for the discussion of observations, equipment, software, and how to use Electronically Assisted Astronomy (EAA) efficiently to maximize the visual experience. EAA has become an important observing tool that assists in overcoming the adverse effects of light pollution and aids in sharing the experience with others at outreach events.

 

Posts with astronomical images must include:

The name and/or catalog number of the object(s) of interest in the text (preferable) or on the image. Preferable because the area surrounding an object may be of interest.

Additional information to illustrate your techniques and equipment used, to assist other members, is encouraged and appreciated.

 

Please note that post-processing of EAA images is not allowed under any circumstances. One can provide links to ones' post processed images in the imaging fora, your gallery on Cloudy Nights or from another website. This helps to maintain our focus on EAA.

 

Our view on post-processing is basically any enhancement process occurring after the capture software has saved the final image into a storage device. The key word being enhancement; image manipulation like cropping, zooming, rotating, annotating, inverting, and file size compression is deemed acceptable.


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#8 Stargazer3236

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Posted 19 April 2021 - 10:40 PM

Exposure length has nothing to do with EAA. The main factor is that EAA is defined by the "No Post Processing" rule. You can expose for  many minutes if you like, but you cannot do post processing. You can do live stacking processing, like histogram stretch, color adjustment, flats, darks, etc., that is adjusting the output of the stacked image at the time of acquisition, but you cannot adjust the image after you save the image to your laptop.


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#9 nicknacknock

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Posted 20 April 2021 - 12:01 AM

Exposure length could define EAA, just not here on Cloudynights, where members and staff see eye to eye on this matter.

 

Specifically, feel free to take any action to enhance images (histo stretch, calibration frames) WHILE viewing and save what you viewed to share, but no post-processing as then the image you present, has nothing to do with what you were actually viewing.


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#10 Stargazer3236

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Posted 20 April 2021 - 08:46 AM

If you tweak the images while you are stacking them, you can get some very good results, like playing with the histogram, adjusting the colors on the fly, darken the background with black levels, add darks or flats to make your image really shine.

 

Depending on the object I am viewing, like planetary nebula, based on POSS images through a downloadable catalog for planetary nebula and specifically Abell planetary nebula, you can get a sense of what wavelength that particular nebula reacts to. Like OIII (blue/Green) or Hydrogen Alpha (red), you can adjust your color sliders to bring in more blue green to enhance the OIII levels or adjust for more red for the Ha levels. Then you just use the slider to increase or decrease saturation to bring the object out more. I typically will play with the color sliders, get the best throughput of light emitted and then decrease the saturation to black and white so I can get a better image while stacking.


Edited by Stargazer3236, 20 April 2021 - 08:51 AM.


#11 Cliff Halliwell

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Posted 29 April 2021 - 09:23 AM

Another way to define EAA, not that we need a lot more debate, is exposure lengths that keep the people you invited to observe (think outreach) from getting bored.  

 

Exposures are long enough to reveal what you want to show but short enough that they don’t start asking when they will see it.  

In particular, one must never park guests in front of a screen for 30 minutes at the end of which you tell them the image is ‘cleaner’ now.  



#12 DSO_Viewer

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Posted 29 April 2021 - 11:21 AM

Another way to define EAA, not that we need a lot more debate, is exposure lengths that keep the people you invited to observe (think outreach) from getting bored.  

 

Exposures are long enough to reveal what you want to show but short enough that they don’t start asking when they will see it.  

In particular, one must never park guests in front of a screen for 30 minutes at the end of which you tell them the image is ‘cleaner’ now.  

Everyone has their own way of doing EAA and there is nothing wrong with spending time studying an object for a certain amount of time. For me a cleaner image means I can see/reveal more detail by removing the noise.

 

Steve


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#13 cnbilbo

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Posted 29 April 2021 - 11:45 AM

It takes as long as it takes to "see" what you want to see. No observers going to waste time on anything that takes too long when we have a universe full of marvellous things to look at and so little time to do it

 

Steve



#14 DSO_Viewer

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Posted 29 April 2021 - 01:26 PM

It takes as long as it takes to "see" what you want to see. No observers going to waste time on anything that takes too long when we have a universe full of marvellous things to look at and so little time to do it

 

Steve

Yes true, and I guess with so many rainy/cloudy days in the UK you are limited.

 

Steve



#15 cpl43uk

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Posted 30 April 2021 - 03:00 AM

My approach is the opposite! I’m currently like a kid in a sweetshop. There are too many things to look at while the weather permits and so it’s more about how LITTLE time i need for imaging before i can move on to the next target! OK i know i will soon slow down and revisit these beauties with more care and respect but after years of “faint fuzzies” it’s transforming and i can’t yet sit still....


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#16 jdono

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Posted 02 May 2021 - 01:41 PM

Initially I thought I was more into astrophotography than EAA as I definitely do like having a good image at the end of the day. And I still do like astrophotography and I do some processing afterwards. 

 

But once while framing the whirlpool galaxy I just slid the gain slider way up  and there it was staring at me right away, and it definitely was quite a thrill seeing it there immediately. 



#17 Noah4x4

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Posted 03 May 2021 - 12:29 AM

I am sure some folk get enormous enjoyment from post processing an image to as closely as possible replicate a Hubble image. That is Astrophotography as an art form. EAA is about near live observing. If we capture the image as a memento it is coincidental to the primary objective which is beating light pollution to see more that faint fuzzies through an eyepiece. However, EAA software and techniques have advanced so much it has become an easy path to credible AP, but will never mirror long exposures on a £15,000 mount. I feel we are comfortable with the simplest definition....no post-processing.
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#18 Mikehuerto

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Posted 03 May 2021 - 05:54 AM

I think you can have have your cake and eat it. 

- Adjust as best you can in Sharp Cap before saving image - and post in EAA forum. 

- Save RAW files or FITS file  to produce AP in program(s) of your choice and post in AP forums. 

 

Generally I've started only post-processing my best EAA outputs .




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