Quote:
Originally Posted by OzEclipse
The crop factor changes the 600 rule to the 400 rule when going from a full frame to APS-C.
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Joe, that must depend on the camera. Canon have a 1.6 crop. Sony have a 1.5 crop. I forget what Nikon is but it is a bit different again. So does 400 apply to Sony and should it be 375 for Canon?
Quote:
Originally Posted by OzEclipse
However, the crop factor does not change the focal length, it changes the FOV. When using my formula, do not multiply FL x crop factor in my formula.
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I added the chip size to my spreadsheet so it can calculate the "effective" focal length so I can use that in the FOV.
Quote:
Originally Posted by OzEclipse
Also with 24MPx, you can get away with a lot more than 4 Px of trailing. It goes without saying that these fixed tripod images usually get shown a bit smaller. Let's say you can accept 4 Px trailing at the final displayed image and you are going to scale the image to 800x1200 Px(20% scale of the 4000x6000px original).
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That's certainly true on IIS. 800x1200 is about as big as you can upload at any reasonable quality setting.
If today's predicted thunderstorms clear tonight I'll see what 80sec looks like at 14mm. (Jonathan is the one with the 8mm lens.)
The numbers show why the 150-500mm @500 has to go on my StarLapse. You don't get much light in 2.3sec.