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View Full Version here: : Upgrade from Andrews 30mm UWA 80 degree EP


davewaldo
23-10-2006, 02:10 PM
Hi All.

I'm keen to find out what you guys think would be a better EP than the Andrews 30mm UWA 80 degree EP. I have a F5 dob and I don't really like the level of aberations in the Andrews EP.

I havn't bought any EP's yet (I still have the basic GSO possls which came with my dob) but I think the Andrews EP is a bit expensive if I'm just going to want to upgrade latter.

I have thought about the Stratus 30mm but it only has a 68 degree field.

So is there a better EP for under $350?

Cheers

Dave.

janoskiss
23-10-2006, 02:26 PM
"... but it only has a 68 degree field." - geez talk about a bad case of FOV gluttony. :P If you want an ultrawide around 30mm that works well at f/5, you're going to have so spend considerably more than $350. The 28mm UWAN is one of the least expensive options around but even that is closer to $500. The 30mm "Andrews" aka 1rpd will give you only about 60 degrees of usable FOV.

davewaldo
23-10-2006, 02:44 PM
haha I love the emersed feeling. But I also like a well corrected image.

I am a photographer and I notice poor image quality quickly and it does annoy me. So perhaps a 30mm Stratus would be the better option. I have been quoted $245 for one of these 2" Stratus EPs from bintel.

I could always remove the bottom section and then barlow it in a UO 2" barlow (which I plan to be my second purchase).... This would then give me a wider FOV?

What do you think of this option Janoskiss?

Cheers.

janoskiss
23-10-2006, 02:57 PM
I don't know the 2" Stratuses and whether they have a removable half like the 1.25"s (but probably no).

You could always wait for John B to sell you his 27mm Panoptic as he upgrades to the 30mm XW. :whistle:

Satchmo
23-10-2006, 03:57 PM
Hi Dave

You'll have to spend upwards of $1000 for a 31mm Nagler to improve the edge performance in an F5 . At 40mm field diameter the coma and astigmatism is getting severe. But then the field of view is great, I recommend putting a cardboard mask with 7.5" hole over the front , not as much light but the Andrews 30mm will be much sharper at the edge and you'll gain all that extra sharp field at effectively F7.

Mark