Sorry another question

[michaelg]

Do you need a laser collimator for a dob or is a Cheshire eyepiece sufficient

will I be able to align the secondary mirror with a Cheshire

thanks

[WaveSoarer]

A Cheshire is sufficient for aligning both the secondary and the primary. The secondary alignment is achieved using the Cheshire cross-hairs, which need to be aligned with the central polo mint circle on the primary by tilting the secondary. It may not be possible to see the primary mirror clips with a Cheshire as it might not be possible to rack the focuser in far enough for this, but that's the job of the Cheshire cross-hairs anyway. Aligning the secondary by viewing the primary mirror clips is for the colly cap method (a colly cap doesn't have cross-hairs). The laser can give more accurate results but you need to be careful to avoid certain alignment errors.