I'm going to get a short 80 mm scope, and I currently only have 1.25 accessories. With a 480 mm scope, the max field is about 3.25; with a 600 mm (ED80), the max field is about 2.6. Will I be wanting a wider field? I know some of the open clusters won't fit in this field. A wider field might negate the need for a finder, but it's a pretty big price jump to 2". No photography, just visual.
2" mandatory?
Started by hemismith, 07/19/2005 08:20PM
Posted 07/19/2005 08:20PM
Opening Post
Posted 07/19/2005 10:56PM
#1
Well, if you have 1.25" diagonal, try the scope out in 1.25inch mode, and you'll figure out soon enough if you want something wider.
For an ST-80, I wouldn't bother; with the ED80, I would. That's me.
On the other hand, if you need to buy a diagonal, get the 2inch now, even if you only use 1.25" eyepieces for now. If you ever want to get a 2inch ep, or you get a different scope with a longer focal length, you'll have the option.
For an ST-80, I wouldn't bother; with the ED80, I would. That's me.
On the other hand, if you need to buy a diagonal, get the 2inch now, even if you only use 1.25" eyepieces for now. If you ever want to get a 2inch ep, or you get a different scope with a longer focal length, you'll have the option.
Posted 07/19/2005 10:57PM
| Edited 07/19/2005 10:58PM
#2
The 2-inch format is certainly not necessary. Unfortunately, none of us can predict whether or not you'll be wanting a wider field. (If I had that kind of foresight, I'd be rich! 
) However, I can offer my own personal experience and perspective.
I have three refractors in the f/5-f/6.7 range. Two of them are 2-inch capable (75mm Pentax & 80mm Stellarvue), but I've never felt the need to maximize either scope's field of view. I have had the opportunity to feed both scopes with 35-40mm wide-field 2-inch eyepieces; and yes, the views were indeed wonderful. However, when I want expansive views of star fields and clusters, I always seem to reach for one of those handheld "twin refractor" systems, otherwise known as binoculars.
15x binoculars with 70mm objectives and ~4.5-degree fields are easy to find and fairly inexpensive. Even wider fields can be had (albeit at 10-11x) in the 50-70mm aperture range. Several 10x50s yield 6.5-degree fields. Sure, some refractors can yield fields a little wider in the 10-15x range, and they can yield a little more magnifcation at similar fields of view, but that slight advantage can end up costing a pretty penny (depending on scope &/or eyepieces).
For some folks, a good pair of wide-field 70mm binoculars is just the ticket. -And, as a bonus, they allow the use of both eyes.
Cheers & best wishes.
-Dan
) However, I can offer my own personal experience and perspective.I have three refractors in the f/5-f/6.7 range. Two of them are 2-inch capable (75mm Pentax & 80mm Stellarvue), but I've never felt the need to maximize either scope's field of view. I have had the opportunity to feed both scopes with 35-40mm wide-field 2-inch eyepieces; and yes, the views were indeed wonderful. However, when I want expansive views of star fields and clusters, I always seem to reach for one of those handheld "twin refractor" systems, otherwise known as binoculars.
15x binoculars with 70mm objectives and ~4.5-degree fields are easy to find and fairly inexpensive. Even wider fields can be had (albeit at 10-11x) in the 50-70mm aperture range. Several 10x50s yield 6.5-degree fields. Sure, some refractors can yield fields a little wider in the 10-15x range, and they can yield a little more magnifcation at similar fields of view, but that slight advantage can end up costing a pretty penny (depending on scope &/or eyepieces).
For some folks, a good pair of wide-field 70mm binoculars is just the ticket. -And, as a bonus, they allow the use of both eyes.
Cheers & best wishes.
-Dan
Posted 07/20/2005 12:14AM
| Edited 07/20/2005 12:46AM
#3
I also love the wide field views. My choice is a pair of WWII German 10x80 flak binoculars.
I have them mounted on the original steel tripod & they give wonderful views. They were made primarily by the companies--Moeller, Leitz, & Busch.
My pair was made by Busch & with the giant prisms & big Erfle eyepieces they have a FOV of 7 degrees 32'. It really does almost take your breath away.
I bought mine in May of 2002 from Charlie Orzech of NC.(Hi Charlie). You can find them fairly easy for $700-$800 I think. I got mine on Astromart. Also, Texas Nautical Repair in Houston (Takahashi) has a reconditioning & repair service for them.
If you have ever looked through a pair of the big 10x80's you wont forget it!
I would really like to hear from others about their experiences using them for wide field viewing.
I have them mounted on the original steel tripod & they give wonderful views. They were made primarily by the companies--Moeller, Leitz, & Busch.
My pair was made by Busch & with the giant prisms & big Erfle eyepieces they have a FOV of 7 degrees 32'. It really does almost take your breath away.
I bought mine in May of 2002 from Charlie Orzech of NC.(Hi Charlie). You can find them fairly easy for $700-$800 I think. I got mine on Astromart. Also, Texas Nautical Repair in Houston (Takahashi) has a reconditioning & repair service for them.
If you have ever looked through a pair of the big 10x80's you wont forget it!
I would really like to hear from others about their experiences using them for wide field viewing.
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Posted 07/20/2005 07:44AM
#4
Thanks for the advice. I've heard wonderful things about those big binoculars, but I've never had a chance to look through any. I met one guy who has a pair of military 100 mm apochromatic binos and he says the view is truly spectacular.
Unfortunately for now I need a single multi-purpose scope, which on my budget will have plenty of limitations. I've always loved wide-field photos, but I would also like to be able to view the moon and planets, as that's what my kids are more impressed with. I was initially thinking Stellarvue/William-Optics and ruled out the ED80 because I thought it was too big to take on a plane, but Jon says the shield can be removed. It seems for my money the ED80 would be the best choice if I want to see anything of the planets, but the field is a bit narrower than the others. I do have a pair of Pentax 7x50 binos which may suffice for the widest views. I already have a decent 1.25 diagonal -- I wish I would have gotten a 2" but couldn't justify it at the time. I thought about just getting it and trying it out, but William Optics has some package deals with 2" diagonals that are making me think twice about the ED80 if I'm going to end up wanting a 2" setup. So hence my post. Of course, a 2" inch setup will be more important with the ED80, so it's kind of backwards. The ED80 isn't as good a deal if I need 2" accessories for it but not for the others.
Unfortunately for now I need a single multi-purpose scope, which on my budget will have plenty of limitations. I've always loved wide-field photos, but I would also like to be able to view the moon and planets, as that's what my kids are more impressed with. I was initially thinking Stellarvue/William-Optics and ruled out the ED80 because I thought it was too big to take on a plane, but Jon says the shield can be removed. It seems for my money the ED80 would be the best choice if I want to see anything of the planets, but the field is a bit narrower than the others. I do have a pair of Pentax 7x50 binos which may suffice for the widest views. I already have a decent 1.25 diagonal -- I wish I would have gotten a 2" but couldn't justify it at the time. I thought about just getting it and trying it out, but William Optics has some package deals with 2" diagonals that are making me think twice about the ED80 if I'm going to end up wanting a 2" setup. So hence my post. Of course, a 2" inch setup will be more important with the ED80, so it's kind of backwards. The ED80 isn't as good a deal if I need 2" accessories for it but not for the others.
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