How important is collimation accuracy?

[AndyWB]

I had a chat with Moonshane at SGL9 about this; I was determined to collimate my scope within an inch of it's life.

He said essentially that for visual, it doesn't have to be spot on. You won't notice the difference between perfect and good. He then went on to make some fairly significant adjustments (I wasn't being brave enough with the secondary) to my dob.

Despite some big adjustments, it made no difference at the eyepiece.

I have since experimented - decollimating the primary a bit to see if I could spot much difference. I couldn't. Maybe I wasn't brave enough to thoroughly decollimate my scope enough to make a difference.

That said, all that's for visual use - imaging does take collimation to another level, I believe.