Pentax, the other side of the argument

davidpretorius · #1 21-11-2005, 09:21 PM

Ok Rob, your turn mate!!!!!!!,

For my 10" F5 dob

I have look thru naglers, but i believe them to be overpriced for what you get.

I am aiming at the tv plossls or maybe even the radians.

maybe a 7mm and a 11mm or 12mm. I will be barlowing them with say 2.5x

I want a good high power eyepiece and a medium.

I have a 2.4x barlow and want to eventually get a 2.5x tv powermate and a 5x tv powermate

What will satisfy my itch, do Pentax do a radian or plossl line? I am not all that fussed about having a gazillion degree view in a medium or high power eyepiece. I think 55 degs should be fine for planetary and closer inspections of dsos!!!

You have the floor Sir Rob

Starkler (Geoff) · #2 21-11-2005, 09:53 PM

The pentax XL was a close competitor to the radian, which is sadly a discontinued line.
65 degree field and 20mm eye relief. About $200-$210US on astromart 2nd hand.
Radians go for around $180US but the pentax is better

davidpretorius · #3 21-11-2005, 09:57 PM

i have heard about the xw's, why this fascination with such wide views in high / med power at the expense of something no doubt???

does every design have to be a nagler, is it really practical in 15mm or less????. i am starting to hear guys talk about plossls and orthos again????

i love my 30mm ultrawide, but unless there is a specific set of clusters that must be viewed at high mag, but wide view, i can't see the $$ value???

Starkler (Geoff) · #4 21-11-2005, 10:08 PM

If a plossl keeps you happy, you'l have a lot more money in your wallet

For me, having gone the widefield route, I cant go back to 50 degree plossls.

Robert_T · #5 21-11-2005, 10:25 PM

Hi David - the key question is what do you want to look at. If it's mainly planets (as with me) then there doesn't appear a lot of point paying lots more to go wide. Better to go for high quality narrow FOV with a narrower price tag. I find for planetary that the University Optics HD orthos (~$125 AU) are hard to beat and they only have a ~40deg FOV. They're nice and contrasty and expect they'd be equally good for small deep sky objects. I've also got a couple of Takhashi LE eyepieces (~$290-300AU) that have more like a Plossl fov (52 deg though for some reason it feels wider); they are brighter and seem to show star colour better than the orthos.

Anyway that's my 2c worth

cheers,

wavelandscott (Scott) · #6 21-11-2005, 10:38 PM

I've got a 7 mm XW Pentax...it is a nice eyepiece (I've got a couple of Naglers too and a Panoptic).

The colours are "cooler" (for lack of a better description) than the Naglers to me...It is sharp and on the moon/planets things look a bit crisper to me than the TV stuff barlowed...

Now don't get me wrong, I like the wider field of the Naglers when I am trying to find things and looking at DSO but the Pentax is a very good eyepiece...lots of eye relief too.

I'd encourage you to try them yourself and see...they do have a different "feel" than the TV gear. All that said, for the money, it is hard to go past a good plossl...

iceman (Mike) · #7 22-11-2005, 06:10 AM

Dave the pentax is no cheaper than a nagler, so if the naglers are overpriced then so are the pentax's.

They're both very nice eyepieces and the 7mm Pentax would make a marvellous planetary eyepiece.

#8 22-11-2005, 08:05 AM

David,

I read you post last night but didn't have time to reply, Has it been edited
since then?

Actually if you want a good planetary ep at a reasonable price you really cant
beat UO HD's I have the 18, 12, 9 and 7mm. The 12mm barlowed 2x was my
favourite planetary setup. Also I think the narrow FOV is better for planetary
where it allows you to focus on the subject. The main difference I see in say
an UO HD and the XW is FOV and in the UO HD the planets disc look slightly
over exposed than in the XW which present a cool crisp neutral feel.

In the end I would use the XW over the UO HD becuase they allow me to sit
and observe for hours with a comfortable size aperture at the eyeball end.
See image below.

Regards,CS

davidpretorius · #9 22-11-2005, 09:37 AM

Thanks rob, I really appreciate everyones input regarding these.

It will come down to how much I want to look and planets and I mean really look at planets, not just a quick couple of passes across the fov.

#10 22-11-2005, 09:37 PM

David,

Here is something else to think about, no reason why a toucam, digital or even a digi cam
cant be hooked up to it. I was thinking Planetary and solar imaging with it, not really
sure about long exposure dso though

Edit: oooop's forgot the url

http://www.pentax.co.jp/english/prod.../scope/pf-ds1/

regards,CS

RapidEye · #11 07-12-2005, 07:26 AM

I'm with Rob (mostly) on this - no suprise, I was one of the folks prodding him into getting a 10mm XW earlier this year

A couple of points:
1) Why do you want the widest FOV???
For a dob driver, that means you have to bump the scope along less often.
For a tracking scope driver, that means you can go with higher power (read more contrast) on a large object and still get it all into the same FOV.

2) The Radians are nice, no doubt about it, but I like the Pentax better for a couple of reasons.
The adjustable eyecup is awesome. I can go between wearing my contacts and/or glasses without any issues on eyeplacement
The Pentaxes are physically bigger, so they are more comfortable to use AND don't fog up quite as bad as the Radians.

I still keep my plossls for when I let the kids look through my scope, but once you go Pentax, you'll never want to look through a plossl again

Good Luck!