End Cap

[davidlf]

Hi...Ive got a Tasco 302012 reflector which i bought 20yrs ago and have just started using it again. Ive bought new lenses for it and collimated it with a laser. All in all it seems a very well made telescope even to the extent of taking .96 EPs and 1.25 EPs with the removal of an adaptor that came with it. My question is what, is the difference between viewing with the end cap off or viewing with the complete end open. I have tred this morning and with the whole end tube open the image seems brighter and sharper, but will this be a benefit at night?

Thanks for any replies I get

[NGC 1502]

Do you mean that the end cap has a smaller removeable section ? As your

scope is a reflector, I would use the scope with the whole cap removed.

Some use a smaller opening to "stop down" the aperture in poor seeing, but

only with a large scope, and many will debate the wisdom of doing that.

With refractors, some do the same to reduce chromatic aberation. But with

a modest aperture reflector, I would remove the whole end cap, unless you

are using a solar filter over the smaller hole, which is usually placed " off axis"

ie to one side, to avoid the secondary mirror and spider supports.

By the way, welcome to SGL !

Best regards, Ed.

[davidlf]

Thanks for the reply and the welcome. Yes it is a smaller removable section...somehow i think ive been using it wrongly all this time , your reply make alot of sense...thank you

[glowjet]

Hi David,

A very warm welcome to SGL, Ed is on the ball with the answer to your question and, just in case, its not to assist viewing the Sun under any circumstances, I am sure you were aware of that but some of our new members just starting out, who have the same type of lens cap, may not be,