1.25" v's 2" accessories

For starts I will not make your mind up.

Fact #1 all eyepeices are not best used in all scopes.

Fact #2 is that what eyepiece you used depends on what you want to
look at and what scope you are using at that time.

Some basic generalities:

1) 1.25 inch eypieces are generally limited to about 55 degree field
of view max. 2 inch eyepieces can achieve higher fields of view.
Upwards to 80 degrees.

2) Generally speaking 2 inch eyepieces are heavier and cost more due
to larger diameter and thickness of the glass used in 2 inch
eyepieces.

3) Longer focal lengths are better off in 2 inch eyepieces. Generally
greater than 30 mm focal length eyepieces.

Also limiting your choice to just eyepiece diameter is limiting visual
performance. A good selection of eyepieces will have both for
different viewing conditions and objects.

The only recommendation that I can make it that you have a selection
that comprises of both. Most of you 2 inch eyepieces will be used for
low pwer and wide field of views. Most of your 1.25 inch eyepieces
will be short focal length for high magnification and specific
viewing. Even some of your eyepieces can be narrow field of view for
double stars and planetary work.

james



On 31 Dec 2005 12:16:01 -0800, "Starboard"
wrote:

+As a astro-newb and soon-to-be owner of an 8" Dob (which for those not
+familiar, can accommodate either 1.25 or 2" eyepieces & accessories), I
+am clueless as to the advantages and disadvantages between the two, and
+hence, also clueless into which size future investments should be made.
+
+I guess one could say I have put the cart before the horse in that I
+have already made purchases for 1.25" accessories, e.g. filters and
+barlow... I did this because it seemed money well spent; 5 filters and
+barlow w/ shipping for $90. In my mind, I was maximizing my abilities
+with what accessories where coming stock with the Dob.
+
+However, if 2" is "noticeably superior", then I am "destined" to resort
+to 2" (and all necessary, associated, accessories), ergo making all
+current 1.25" purchases - wasteful. Of course I could send back the
+1.25" accessories and exchange them for 2", but then I'd have to
+purchase 2" eye pieces as well; spending more money. Is it worth it?
+
+Please make up my mind for me.....
+
+Errol NOLA