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Old 08-10-2020, 08:51 AM
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PKay (Peter)
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Resolving power Question

I am currently planning my next image, and I do have a question :-)
Sorry about the maths.

See the attached zoom into M42:
Image details are:
Scope used: 150mm APO (resolving power about 0.80 arc seconds)
Camera: 4656 X 3520 pixels
Image scale 0.728 arcsec/pixel.
Dimensions in pixels: about 1012 X 800.
Dimensions in minutes: about 9.27' X 7.3'

Now, using the 305mm f/5 Newt.
The stated resolving power is 0.45 arc seconds.

Image scale: 0.55 arcsec/pixel (using the same camera).

Now I want to zoom in using either a Barlow, or eyepiece projection.

To get the required image, I need to use a 3X barlow (or appropriate eyepiece).

This will result in a FOV of about 10 X 13 arcmin (which is ideal).

However, the image scale will be 0.17 arcsec/pixel.

So I have exceeded the resolving power of the 305mm Newt (I think).

Question is:

Will this matter?
Attached Thumbnails
Click for full-size image (M42_MergeMosaic_ABE_BN_AWT_CC_HT_CT_Crop.jpg)
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