10" Dob - 6.7, 14mm, 28mm - next eyepiece?

[SpoonyPizzas]

Good morning all,

I've saved up some money and am wondering what I should perhaps go for next in terms of EPs?

So far I have:-

1.25" 6.7mm ES 82 degree

1.25" 14mm ES 82 degree

2" 28mm ES 68 degree

I was thinking about a 30mm 82 degree (heard good things re: 30mm 82 for a 10" dob) or 34mm 68 degree?

Cheers,

Spoony

[Mark at Beaufort]

Hello Spoony

I assume your Dob has a focal length of 1200mm and therefore is f4.7.

I would have thought that the 28mm ES would be your maximum - exit pupil with this EP is 5.9 and to go further you are wasting light. The 30mm EP - exit pupil is 6.35 and the 34mm is 7.26.

Personally I would buy something between 18mm and 20mm - the 18mm ES would give a mag of 67, exit pupil of 3.8 and a FOV of 73 arc minutes.

[SpoonyPizzas]

Thanks Mark

[Paul73]

I agree with Mark. 20 or 22 would be good options. I'm awaiting delivery of the ES82° 30mm as we speak. It might be a tad ambitious on the exit pupil. But many seem to get on with it fine so I'm giving it a whirl (and post a report).

The 24mm is my most used eyepiece but it is very close to the 28mm.

As for the 34mm. Don't go there. The view will be washed out and rubbish.

Paul

[SpoonyPizzas]

Thanks Paul,

Would appreciate the report - can you drop me a message possibly when you post your report?  Enjoy! :-)

[Paul73]

Thanks Paul,

Would appreciate the report - can you drop me a message possibly when you post your report?  Enjoy! :-)

Will do!