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Posts Made By: Tom Hole

September 11, 2003 04:03 AM Forum: TeleVue

Powermate vs. eyepiece only

Posted By Tom Hole
IMHO, you lose nothing when you put the 2.5x powermate in front of any ocular. As a matter of fact, you may actually gain something: a few extra $$$ in your wallet from not having to buy another premium eyepiece.

YMMV, my $.02 worth, in my experience, etc, etc, etc...

Clear skies,

Tom

September 13, 2003 06:34 PM Forum: Binoviewers

Re: Denkmeier (Denk) Standard vs. Denk II

Posted By Tom Hole
Drat! I'm glad you had a chance to try them out first. If you ever have the opportunity to try again, do. Can you observe without the glasses? I guess if they are for astigmatism, probably not. If they are for mismatched eyes, maybe the dual diopter adjustment on the Denk II's would allow you to observe without them. Did the Denk II's you tried have the dual diopter adjustment feature?

Clear skies,

TOm

September 17, 2003 11:47 AM Forum: Equipment Talk

High Power EP

Posted By Tom Hole
JOE,

I'd like to add the 5.2mm Pentx XL to that list (or the new 5mm XW). I think you'll find it may be one of the most comfortable high power ep's around. And, as a benefit, it has one of the sharpest, contrasty wide field views going. The Pentax XL line is my favorite ep 21mm and below.

Clear skies,

Tom

September 20, 2003 04:51 PM Forum: Chinese Optics Imports

Update from Bill, When?

Posted By Tom Hole
From the sound of it, it isn't a minor problem. As perfect as possible is fine, but the 1026 that Al has is unusable in his words. That's pretty serious. Plus the issue with the focuser and the diagonal. Not a pretty picture being painted.

I am thankful that Bill is dedicated to making it right. That's a good thing. I just wish he would talk to us. I think $100,000 gives us that right.

CLear skies,

Tom

September 20, 2003 04:53 PM Forum: Binoviewers

Yet another this vs that question.

Posted By Tom Hole
I thought the Denk FMC's were the same price as the Denk standards? I could be wrong.

TOm

September 22, 2003 12:14 PM Forum: Equipment Talk

Building a mount - Engineering Questions?

Posted By Tom Hole
Anthony,

John Davis makes custom GEM's. He has a Yahoo group that he uses for most communication:

http://groups.yahoo.com/group/Gemini-Instruments/

He is a right friendly fellow and may be able to help you out. Here's a picture of his 125 lbs capacity mount on a portable pier he made.

Tom

September 25, 2003 09:36 PM Forum: Equipment Talk

Rechargeable batteries with lxd-55 mount???

Posted By Tom Hole
Ricardo,

Return them to Rat Shack and spend the $50 on a jump start battery pack. The rechargeables might last an hour and may not work at all, even with 2 more. A weak power supply will frustrate you to no end.

Clear skies,

Tom

September 26, 2003 12:37 PM Forum: Binoviewers

Harry's new focal reducer works great

Posted By Tom Hole
Don,

Can you describe your optical train? Are you using a visual back, 2" or 1.25" diagonal (shorty or regular?), SCT crayford focuser or any other whacky extras. My perfect world would be a C9.25 with an SCT crayford focuser and a 2" diagonal and the binoviewers with star sweeper/focal reducer. But I don't think the 9.25 has enough back focus to accomodate all of that.

Thanks,

Tom

September 27, 2003 01:57 AM Forum: Binoviewers

Ranking the best Bino's

Posted By Tom Hole
Well, I don't know which is the best, but there are a few things that I have learned in the past few months with the Televue binovues.

First, 2x is too much for a corrector. I have a moderate focal length dob at 1200mm, but I sure do miss the wide field views. Even with the 24 Pans, I'm stuck at .7 degrees. This is intolerable for most deep sky work. But the 2x corrector is a marvelous piece of optical engineering and is fantastic for high power views.

The lack of a filter option is somewhat annoying. I compensate by putting one filter on one ep and leaving the other unfiltered. This has interesting results, not always desired.

The ep holders are very solid. The coatings are impeccable. The price is high, but fair.

My Denk standards with the two OCS's are in the hands of Mr. Postman and should be back tomorrow. The first thing I'm going to do is put the 2" OCS on one of the binoviewers and do some low power sky sweeping. I haven't had a chance to do that yet with the 24 Pans and I'm very excited. Then I guess I'll have to get down to the nasty job of figuring out which binoviewer I'm going to keep. I'll let you know how it goes. Tough job, eh? I have contemplated selling both and getting the Denk II. But I have grown attached to the Televues and talking to Al, so that would be a tough one.

Clear skies,

Tom


September 27, 2003 01:00 PM Forum: Binoviewers

Do I have this straight?

Posted By Tom Hole
Chris,

You have it correct, sir.

The only thing I will add is that swapping power modes on the 2" OCS at night is not as simple as it is in the garage or den. The logistics of unscrewing it, finding a place to put the binoviewers, reconfiguring the OCS and then screwing it back on the binoviewers is no simple feat. In the meantime, your target of interest has drifted well outside the FOV. Unless your 10" tracks, and even then the OTA may be off balance because you had to remove 2 lbs plus of stuff from the front end. Been there, done that. I've resigned myself to buying more pairs of ep's rather than using the high power mode of the OCS. That's my opinion, btw.

For wide field, the 24 Pans will be your widest possible true field of view. They have a field stop of 27mm. A 32mm ep has a field stop of 27mm, so it won't provide any larger FOV, just a lower magnification. The 20mm KK Widescan III has a reported field stop of 29.5mm, but I'm not sure how they do that. I didn't buy a pair of them because they were reported as poor performers at f/5. Even though I do all of my viewing with binoviewers (which equates to f/6 or so), I want my ep's to be able to perform in my f/4.7 dob in mono mode as well.

Clear skies,

Tom

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