Error in TLAO?

[Spec-Chum]

I've got the forth edition of this fantastic (the one in the spring binder thing) book and I think I've spotted an error on page 21 where it explains about the Longest useful eyepiece.

At the bottom of that section is mentions that M_min is around A / 7 in mm or 3.5 x A in inches. Wouldn't that be 5.3 or there abouts.

If not I dont get it lol

[umadog]

What does it say?

[Freff]

Something is missing in the post I think.

[Spec-Chum]

lol sorry Asus transformer went all weird, keyboard stopped working and then acted strange

[RikM]

It seems about right to me. Perhaps a little too wide but not far off.

For my 250px: 250 / 7 = 35mm or 3.5 x 10" = 35mm eyepiece. That would give a 7.4 mm exit pupil, which is too much for me but would be okay for some.

[Spec-Chum]

Please ignore this thread, I'm an idiot. I put 300mm instead of 200mm for A so I was using 300mm and 8 inches lol...

I was good at maths once lol