Posts Made By: Dennis Freeman

I've read this and similar posts with interest since I just purchased a 10" XTi. While looking to purchase Left Turn at Orion, I noticed one review which made me start thinking (a sometimes dangerous proposition). Does the sketches in this book reflect the reversed view of a neutonian or the correct image of a refractor?

Thanks everyone for your advice. It's greatly appreciated.

Using something disposable sounds like a smart idea. I'll try the Q-tips with a disposable lens cloth as a backup. (Floyd, do you know the supplier for the lens cloth you mentioned?)

FYI, I just bought a waterproof case for the eyepieces and misc. equipment I'm acquiring. My plan is to keep the eyepieces in the case with caps on unless I'm actually using one so moisture/dirt shouldn't be a problem, even in storage.

Floyd, you're right that is a great price for a battery system and sure beats anything made specifically for 'scopes. The one thing I would remind you of is that a jump start battery will be optimized for cold cranking amps and have thin plates. I.E. it will wear out considerably faster because you won't get as many recharges out of it. To maximze your usage, keep the discharge to a minimize (under 10% would be best).

Of course, when the time comes you can always replace it with a better, deep cycle battery which is designed for discharges of up to 80%. And then you'll have one great system for a great price.

Thanks for the advice. I have a better idea now of the practical effects. Nagler's article was a good primer.

Reading the thread to this points made me realize I have to make to corrections.

I have a 7mm UO Ortho and the Barlow is the Shorty Plus.

Thanks for your comments/suggestions.

Thanks everyone for the info. so far. I do seem to remember reading that barlows do affect the eye relief. Does anyone know a formula to assess this impact or do only the manufacturers know for sure?

The reason I started thinking about this is that I have a 35mm Panoptic and plan on getting the 27mm as well (24mm and 19mm eye relief respectively). Right now I don't have any wide FOV mid-range eyepieces between a 21mm Stratus and an 8mm Hyperion. I do have an 8-24mm TV zoom that will help fill the gap temporarily until I can afford better. I've been thinking of getting a Televue Big Barlow instead of discrete EPs.It will in effect be two for the price of one.

Anyone with practice experience on this? Is the extended eye relief an issue where I would want to go with a Powermate?

I lean toward wide field, because I have an 10" XTi (1200mm, f/4.7)and, of course, it's easier to keep the subject in view. My goal is eventually to end up with UW (@80 degrees) EPs over a period of years.

BTW, both my wife and son have astigmatism issues which is why "the family" EPs have longer ER. Some of you may recall that I have a 7mm OU ortho and 7mm T1 for myself.

Last query. Can anyone recommend a good primer (as in beginner) book on optics so I can begin to understand how all the factors interrelate?

Thks. in advance

If you do a search of the forum for cleaning, you'll find all sorts of useful advice.

I believe the FOV is 65 degrees.

Floyd,

It looks beautiful. Like a work of art or some kind of laser cannon to deflect asteroids.

I'm curious, how long do you think it will take you to set this up?

Dennis

Before anyone could even attempt an opinion, they would need more information. Like:

What is condition of scope?
What EPs are included?
Is a tripod included? If so cg-3, table top, etc.
Does the drive motor work? Hand controller incl.? Power cord incl.?

Perhaps a better suggestion is to do a search on the classifieds and see what the pricing is for what you get and then you can make up your own mind.