laser and cheshire ?

[rory]

theres a revelation laser collimator along with a cheshire in one sale. would it be a good idea to have the two ? or is that overkill ?

[umadog]

If the combo tools have a sight-tube that helps to position the secondary in the focuser (so it appears rounded and centered). The laser won't help you achieve this adjustment. It's for this reason that you want both tools.

[Lenny147]

Yeah i would say both are a must but its a touchy touchy subject on here

[umadog]

Well, both aren't a must simply because a combo tool measures the same axial alignment signatures as a laser. A laser is more convenient on a larger scope, but it's still quite possible to use a cheshire to adjust the primary even though you have to go back and forth between eyepiece and mirror. A laser is more intuitive because when you're axially aligned, the laser beam is on the optical axis. You can really visualise what it means to be axially aligned. In contrast, you have to think about what the view through a combo tool means. Also, with a laser you don't have to clip and LED to the spider to align in the dark. The combo tool is more simple and durable, though.

[rory]

okay ,cheers guys. although the price was pretty good, i feel a cheshire and sight tool would be fine. dont REALLY feel a need for a laser.