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hermitcrablast Wednesday at 7:41 PM1 replyview on HN

What sort of magnification do you need to get photos like that?


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js2last Wednesday at 11:41 PM

The Redcat scope FL is 250 mm. The Askar scope FL is 1000 mm. The camera has an APS-C sensor (23.5 mm x 15.7 mm) giving it a crop factor of about 1.5x compared to 35 mm film (where 50mm is considered 1:1 human vision field of view).

So:

Redcat: 250 / 50 * 1.5 =7.5x magnification

Askar : 1000 / 50 * 1.5 =30x magnification

This is deep sky photography. Doesn't require lots of magnification. What it does require is dark skies and lots of exposure time.

I wish he had more info on his site about his capture process, but it sounds like some of his captures are over multiple nights? I'm not entirely clear on the terminology here:

Integration: 17h 50′

Hα: 30×600″ (5h)

OIII: 31×600″ (5h 10′)

SII: 37×600″ (6h 10′)

RGB Stars: 30×60″ each channel (1h 30′ total)

https://www.instagram.com/p/DToHq5sk_6r/?img_index=1

I may be wrong with all of this. I haven't done any astrophotography since I was a teen and that was just a 50 mm Nikon SLR on the back of a Celestron 8" CST with motorized manual tracking from highly suboptimal skies (Miami, FL). Still, got some decent shots of the Orion nebula.

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