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EAA does pixel scale matter?

EAA
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Clayton Ostler avatar
Clayton Ostler avatar
Ok 
To start out, I understand concepts like image/pixel scale and resolution and how those affect image quality in astrophotography, but……

In my opinion EAA is different because the images are not intended to be processed, but instead we hope to see something (hopefully impressive) on our screens, as quick as possible.

With this in mind, I have some questions/comments

1. Does pixel scaling matter that much? 
2. Logic says "just get the biggest pixels and most sensitive sensor possible"
3. Should I select binning over pixel scale? I mean I could 4x4 bin the camera and seemingly collect a lot of light a lot faster. 

Lets make some assumptions
1. Not going to keep the images
2. Likely short exposures (for sure under 60 seconds, but likely more like 30)
3. Any stacking will be live stacking
4. Probably wont zoom in much, mostly wide field stuff

Lets just say I want a beast of an EAA system, and I dont care to process or keep any images.  Lets pretend I live in a light polluted area, and I cant see much without EAA, so instead of having my kids and friends look into a scope and be unimpressed and disappointed, I instead build an EAA system so they can watch images form quickly on a tablet. 

Thoughts?
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Tony Gondola avatar
Tony Gondola avatar
If you want to build up an image quickly, a fast system will be what you want. Think RASA or Hyperstar.
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Clayton Ostler avatar
Clayton Ostler avatar
I agree, 
Here is where I am right now. I have a few cameras, some ZWO and some DSLR, I have a DSLR with really large pixels and could bin any of my ZWO cameras. Without buying a new scope and knowing I just want to get an image quick, 

1. Are biggest pixels best? 
2. Should I just go 4x4 binning?
3. Is the DSLR with the bigger pixels best best?
Bruce Donzanti avatar
Bruce Donzanti avatar
I did EAA for a number of years before switching over to astrophotography. 

Here are my 2 cents based on your questions......

1. Does pixel scaling matter that much?  Not really. I used a StarlightXpress CCD camera with a 4.54-pixel size but many use ASI294 (larger pixels than the current popular ASI2600, but folks use this camera as well).  Others use a DSLR.  You definitely want a camera with very low noise since you are shooting only 30 or 60 s subs. 

2. Logic says "just get the biggest pixels and most sensitive sensor possible" Sure- but don't obsess over this.  Virtually any current CMOS camera will work.

3. Should I select binning over pixel scale? I mean I could 4x4 bin the camera and seemingly collect a lot of light a lot faster.   I never did binning nor do I recall any of my friends bin the data.


Lets make some assumptions
1. Not going to keep the images- Yes- this is typical but up to you
2. Likely short exposures (for sure under 60 seconds, but likely more like 30) Yes- 30 s is the norm but sometimes 60s 
3. Any stacking will be live stacking- Yes, this is actually a key principle behind the definition of EAA. 
4. Probably wont zoom in much, mostly wide field stuff.  Why?  EAA is great for close-up shots.  My typical setup was a C11" EdgeHD @ f/7 or attach the hyperstar for a widefield.  Frankly, the close-ups are more frequently done.  

In general, EAA is short live stacks and no post-processing.  Other than these two principles, anything else goes.  The whole point of EAA is for a quick look, use it as an educational tool or entertainment for a live audience, etc.  With this said, you can get incredibly nice images of galaxies and nebulae with this approach.

Good luck- you will enjoy the ride.  

Bruce
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