Eyepieces for PST

iceman (Mike) · #1 14-03-2010, 10:29 AM

Do normal eyepieces work just as well in a PST?

I've got a 20mm one that came with it, but will my other eyepieces work equally as well, or is there something special in the coating that makes it work better/worse in a PST?

Cheers

UniPol · #2 14-03-2010, 11:34 AM

The Coronado Cemax eyepieces are supposed to be enhanced and matched to the their series of scopes and I have been happy with the 18mm. Tele Vue Radians work very well in the 12mm to 18mm range however in my opinion you try as many EP's as you can until you are comfortable with. One eyepiece I used the most was a 15mm TV Panoptic but for some inexplicable reason I sold it

.

Cheers, Steve

trent_julie · #3 14-03-2010, 12:20 PM

Mike,

I have the same scope, I prefer a 14mm Radian for the sun disk, or a 6mm Radian for features.

Cheers,

Trent and Julie

casstony · #4 14-03-2010, 12:24 PM

Any decent eyepiece is fine, but zooms are convenient since you don't have to carry extra bits and pieces out with the scope. If you don't have a zoom and want to purchase one I'd recommend the Lunt 7-21 zoom; it's a re-badged nikon. The Vixen zoom is also good apart from the 8-10mm settings where it is noticably soft.

I'd also recommend Sirius Optics for new solar gear - I've been very happy with their service and prices.

h0ughy (David) · #5 14-03-2010, 01:11 PM

meade 5000 15 is ok, or a nagler 9.......... the 17 is ok. But your going to have a DMK stuffed down its throat so whats the problem

sheeny (Al) · #6 14-03-2010, 06:10 PM

I have a set of Cemax EPs and, like Unipol, I like the 18!

But I've also used my 13mm Nagler T6 and it's pretty good too.

Al.

OneOfOne (Trevor) · #7 14-03-2010, 07:16 PM

I generally use my Pentax XW10 as it gives a wider view and larger scale than the one that comes with it, but the image fills around the same percentage of the field...so it looks similar, but bigger...if you get what I mean.

iceman (Mike) · #8 14-03-2010, 07:44 PM

Thanks for the replies.
It's a shame I sold all my good eyepieces

I've still got my 5mm TMB, but that's about it

Like h0ughy said, hopefully soon the DMK will take the place of an eyepiece

GrahamL · #9 14-03-2010, 08:05 PM

I've only looked through a pst once and it was with an... XW 10
While I don't have any idea how other eyepieces measure up It was a
wow of a view .. one for sale here Mike if you want to try one of these great eyepieces

http://www.iceinspace.com.au/forum/s...ad.php?t=58226

Paul Haese · #10 19-03-2010, 09:29 AM

9mm Nagler is what I use. I don't use the Cemax 25 that came with the scope. The TV EP works really well.

psyke777 · #11 10-09-2011, 05:49 PM

I hope this is the best place to continue discussing PST eye pieces.

My Coronado PST came with the Kelner 20mm (I assume that is what K20 means).
But when I used my Orion Edge-On Planetary 9mm the clarity improved dramatically.
Then I experimented with a polarising filter not expecting much but was even more surprised and pleased to see even more details on the sun disk (at the expense of seeing prominenses). Keep the eye piece in the scope loose and rotate it to the best contrasting view.

Since the 9mm eye piece does 44x magnification, and the PST can go up to 80x or 90x, I want to try and get about 60-70x.

I was hoping to find a 1.5x Barlow lens but these seem rare or non-existent.
My plans are to see if I can piece together a 2x Barlow lens with shorter parts to make an ~1.5x.
Another idea is to try a 1.5x Erecting eye piece.

Any thoughts on if I should try for 60-70x and the cheapest best way to get there?

Merlin66 (Ken) · #12 10-09-2011, 07:33 PM

Under average seeing you'll probably find something around the 9-10mm focal length gives the best views.
I use a Pentax 8-24 Zoom which is very handy.

sheeny (Al) · #13 10-09-2011, 08:57 PM

Quote:

Originally Posted by psyke777

I was hoping to find a 1.5x Barlow lens but these seem rare or non-existent.
My plans are to see if I can piece together a 2x Barlow lens with shorter parts to make an ~1.5x.
Another idea is to try a 1.5x Erecting eye piece.

Any thoughts on if I should try for 60-70x and the cheapest best way to get there?

If you have a 2x barlow you could try unscrewing the barlow lens and screw it on the end of the EP. Not sure what magnification you'll get but it will be less than 2 for a standard barlow.

Al.

mozzie (Peter) · #14 10-09-2011, 09:47 PM

iv'e a baader 8-24 zoom and it,s perfect..

psyke777 · #15 10-09-2011, 10:40 PM

Quote:

Originally Posted by sheeny

If you have a 2x barlow you could try unscrewing the barlow lens and screw it on the end of the EP. Not sure what magnification you'll get but it will be less than 2 for a standard barlow.

Al.

Doesn't fit on the "Orion Edge-On Planetary 9mm" but it can on others if I remove the spacer/end(?) from the bottom of eye piece. The threads don't match otherwise. But the eye relief on the others were problematic.

I am pondering some plumbing pipe to make a customised Barlow

for use with the 9mm. (2X Barlow is too much for the telescope and 9mm eye piece at 89x mag)
Hopefully a cheap way to test higher magnifications.

psyke777 · #16 11-09-2011, 11:44 AM

I've done some more experimenting and searching on the net and the formula:

Maximum useful magnification = Aperture in mm * 1.2

looks right. So the best lens is a 8-9mm. Beyond that things get grainy.

jamespierce (James) · #17 11-09-2011, 09:09 PM

10mm Ethos is perfect (if perhaps overkill)... I suspect a 9mm Nagler would be ideal also... There is nothing magical about solar observing as far as I can tell.

cookie8 (Vincent) · #18 11-09-2011, 11:48 PM

John Wilkinson has written a EP review for PST in the Equipment Review section:
http://www.iceinspace.com.au/42-630-0-0-1-0.html
He reckoned a Meade 15mm Plossl is best value for money.

Osirisra (Ken) · #19 12-09-2011, 01:04 PM

Quote:

Originally Posted by mozzie

iv'e a baader 8-24 zoom and it,s perfect..

Me too, it the only one I use on the PST and you are so right it's perfect and super easy to put a camera onto.

psyke777 · #20 01-03-2012, 07:01 PM

A final update on my use of the PST.

My 9mm was not the best choice due to small eye relief 6.5mm and exit pupil 0.9mm, which made keeping my eye in the right place more difficult.

Instead I use a 2x Barlow and a 20mm plossl, 4mm exit pupil and 29mm eye relief, 40x mag. Past 48x is blurry so this is a good comfortable compromise.