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New PST - familiar question

Started by kins, 04/24/2006 10:57PM
Posted 04/24/2006 10:57PM Opening Post
I just received my brand new Coronado PST and what a wonderful treat. I have been involved in astronomy for almost 3 years now, but on Sunday the 23rd of April it was like I was starting all over again.

Anyway, I used three eyepieces with exceptionally great results, as would be expected. A Nagler 12mm T4, a Nagler 9mm T6 and finally a Tak 7.5mm LE. I figured I was covered for more power when I reached for my TV 1.25 2X barlow, but it was too long to reach focus.

Question: Is there a shorty barlow that will work, or should I just go for a Radian 4mm or something to that effect?

I have posted this question on the Coronado forum as well.

Thanks to all who respond,

Steve
Posted 04/25/2006 08:06AM #1
My Celestron Ultima 2x Barlow lens works fine but I rarely use much more than a 6mm focal length (67x) with my PST. I can almost always employ a focal length of 8mm (50x). Most of the time my 8-24mm Vixen zoom eyepiece is all I use.

Dave Mitsky

Chance favors the prepared mind.

De gustibus non est disputandum.
Posted 04/25/2006 09:37PM #2
I HAVE A 2 MONTH OLD PST. AS SHIPPED THE CORONADO EYEPIECES ARE BETTER INCLUDING THE BARLOWS. I HAVE THE 18 12 & WITH BARLOWS ADDS 9 & 6. I HAVE COMPARED THESE TO THE 12 NAGLER T 4 16 NAGLER T 5 5 & 3.5 NAGLER T 6 & 9 NAGLER T 2. WITH THIS MANY GOOD NAGLERS I DID NOT WANT TO BUY ANY MORE BUT I DID. AT .1 ANGSTROM THE CORONADOS SIMPLY ADD MORE CONTRAST.I HAVE TRIED THE CELESTRON ULTIMA BARLOW & IT WILL COME TO FOCUS.I ASLO RECENTLY ADDED THE DOUBLE STACKER FOR THE PST. THE IMAGE IS BETTER FOR CONTRAST ON SURFACE ALTHOUGH DARKER.THE CORONADO EYEPIECES ARE NOT THAT MUCH DIFFERENT WITH .6 ANGSTROM AS IT IS WITH .1. 6MM IS A STRETCH WITH THE STACKED PST

GOOD LUCK

BOB
Posted 04/25/2006 10:14PM #3
Hi Steve,
I've had a PST with Double Stack filter for a year+ now. Having tried about ever eyepiece manufactured with the combination I have similar feels to Bob. The Coronado eyepieces are hard to beat. The next best tend to be simple design (fewer elements) eyepieces. Think 'Planetary'. Interestingly my Zeiss Abbe Orthos do not seem to preform as well as my Pentax SMC EPs. Don't know why but a couple people have done a direct comparison and made the same remarks.
Generally I've found anything below 12mm in an Ortho/Kellner only gives you a portion of the Sun, anything less than about 8mm starts to loose detail depending on conditions even at high altitude (Above 6,000'). I tried my Zeiss Barlow once for fun and it worked fine. I have on occasion been able to use a 5 or 6mm when transparency allowed but not often.
To be honest, except for FOV, I've found little difference between a good 6mm ortho and a 6mm Radian. The ortho has maybe a bit more detail.
Just for fun, try any decent plossls, orthos, or Kellners you may have handy. The results may just surprise you.
Clear Skies, Bill