Posts Made By: William Paolini

Being no expert on the history of EPs and marketing, if I had to guess it would probably be because of the afov. Why make a 25mm 40afov when you can get 50+ deg with nearly as good correction from the Plossl design? And then it's hard for an Orthos at 40 deg afov to compete against a quality 25mm Erfle with 60 deg afov.

I would hazzard that is has more to do with marketing and user preference (i.e. market forces) rather than any optical issue.

See attached pic

See attached pic

Keep your spirits up and remember the old addage...third time's a charm!

When you call, since you've been thru all of this, tell them you want the manager to personally inspect it prior to shipping, personally over pack it for protection, to personally select one that is optically best of all the ones he has in stock, and finally to throw in a gift certificate from the store for a next purchase!

I think you've been thru enough trying to get this. And remember, when you get one that is fonally ok, the wait for 1st light will be well worth it (after adequate cooldown of course)

-Bill

Dave,

Considering all the things I know now, I would have to agree that a 6" dob is probably a best for a start - considering price, performance, capability, and size.

However, as I recall those many decades ago with my 1st scope (a refractor on an equatorial mount), I gave it up for a new scope for mostly one reason...it was just so difficult to point the thing at what I wanted and to find anything!

So even if a 6" dob is all around best, I could still see people getting frustrated because they can't find what they are pointing at. So that means a really wide field finder scope or telerad or green laser should be a MUST. Then, given all the frustrations trying to find messier objects via star hopping and the like for a beginner, I'd say put a push-to computer on it. Added expenses dor sure...so maybe we are down to a 4.25" dob?

Anyway, that' as I recall, was just so frustrating and almost made me quit. So whatever scope, frustration potential really needs to be reduced.

-Bill

Very cool. Thanks for sharing. It all begins with just one new idea...then all of a sudden (metaphoically), everything has changed. This is indeed a very interesting technology with some wide ranging potentials

Mark,

A while back I did a compare of the TV 8mm Plossl vs the 7.5mm Ultima (same as Ultrascopic) on AMart Reviews. On stellar images the Ultima was the clear winner, producing much finer star points and picking up fainter stars (I also have the UO HD 7mm and the Ultima beats it on stars). So looks like you are experiencing the same thing with the 25mm. The Ultima/Ultrascopics are a fantastic performer for stellar work, particularly globs. I think the Ultrascopics are real sleepers and if Orion discontinues them as Celestron did, I think they may be sought after in the coming years.

-Bill

Dennis,

I think a good contributor to the reason is that there really is nothing out there that is truely "perfect," especially in fast scopes. There is a compromise in every design to achieve what they do.

Another reason is like anything else, if you eat pizza every day for 2 years, pretty good bet that you'll get tired of it and move onto another food. Same with eyepieces I think, you fall in love with something, use it regularly, then find something else that does something a little different, and sell one to pay for the other.

And yet another reason is that as we observe more and spend more time, our interests and needs change, so then our choice of eyepieces needs to change. Example, if you started out primarily doing Lunar and Planetary observations, then Ortho's and Plossls with their mid-sized fields do a great job. After some years of that your interests then evolved and you are primarily a DSO person, then wide-field eyepieces fit the bill more.

Finally, some people just make wrong choices. Depending on your scope type, its focal ratio, and your observing site, some eyepieces are just wrong to use, regardless of whether they are from premium manufacturers or not. I think many people sell their stuff because they have gained experience and now realize this.

I have viewed thru (and owned) Televues, Orions, Celestrons, Meades, Sieberts, University Optics, TMBs, Burgess Opticals, Borgs, Edmunds, Russell Optics, Surplus Sheds, and some generics. While the fit/finish/build varies on all of these, all of them have units with are quite excellent when matched to the proper instrument and application. So as a rule, nothing is bad with any of them.

-Bill

Thanks Floyd!
The Hatfield Lunar Atlas is what I'm after with the reward

John Holt said:

Scope focal ratio?

I know it matters sometimes, but if people just have long fl scopes then tell me that. I have a f/5 Newt. But am still interested in their opinions for other designs and FLs.

Thx.