#1  
Old 08-12-2014, 07:02 PM
Hoges (John)
Registered User

Hoges is offline
 
Join Date: Dec 2010
Location: Burrumbeet
Posts: 244
Anyone use the Pentax 200mm 2.8 ?

There isn't a huge amount of lenses available for the Pentax compared to Canon and Nikon, but I've read some reasonably good things about the 200mm 2.8 Pentax lens....except for some purple fringing in high contrast areas. I can't find any astro photos done with this lens. Anyone?

Recently bought the inexpensive Pentax 35mm 2.4 which is a lovely little lens during the day, but a completely different story at night where nearly every star has a nice red circle around it. Wouldn't like to blow a grand on a telephoto lens and have it do the same thing at night.
Reply With Quote
  #2  
Old 08-12-2014, 09:21 PM
Nico13's Avatar
Nico13 (Ken)
Galaxy Hunting

Nico13 is offline
 
Join Date: Jul 2009
Location: Geelong region.
Posts: 944
Hi John,
I also have heard lots of good things about the 200mm but all pertaining to daylight.
I am a Pentax user and have a number of primes but unfortunately they all seem to suffer some aberration to some extent and also some internal reflections on brighter objects at night, some acceptable some not.
I have a rather nice first quality Sigma 24-60 that is great in daylight but suffer the internal reflections terribly at night.
Have you asked on the Pentax forums to see if anyone is doing astro with the 200? Worth a look there I would say.
Reply With Quote
  #3  
Old 09-12-2014, 10:54 AM
gregbradley's Avatar
gregbradley
Registered User

gregbradley is offline
 
Join Date: Feb 2006
Location: Sydney
Posts: 17,877
Which Pentax 200 2.8? I think there may be a few.

The 6x7 seems to do well. I have a 165 2.8 6 x 7 which is sharp wide open and no false colour.

Marc on this site has posted numerous Pentax 200mm astro shots. Perhaps look for one of them to get the exact 200mm model he used. I am not sure now if it was the 6 7 version or another one.

Greg.
Reply With Quote
  #4  
Old 09-12-2014, 12:22 PM
multiweb's Avatar
multiweb (Marc)
ze frogginator

multiweb is offline
 
Join Date: Oct 2007
Location: Sydney
Posts: 22,060
Quote:
Originally Posted by Hoges View Post
There isn't a huge amount of lenses available for the Pentax compared to Canon and Nikon, but I've read some reasonably good things about the 200mm 2.8 Pentax lens....except for some purple fringing in high contrast areas. I can't find any astro photos done with this lens. Anyone?

Recently bought the inexpensive Pentax 35mm 2.4 which is a lovely little lens during the day, but a completely different story at night where nearly every star has a nice red circle around it. Wouldn't like to blow a grand on a telephoto lens and have it do the same thing at night.
I have used a SMC Pentax M 200mm F/4 with a 2" Baader fringe killer filter and a UV/IR cut, Baader also. It did help with the fringing. LMC here. I also used it to do some narrowband and that works great. They're nice and inexpensive prime lenses.
Reply With Quote
  #5  
Old 09-12-2014, 01:20 PM
Hoges (John)
Registered User

Hoges is offline
 
Join Date: Dec 2010
Location: Burrumbeet
Posts: 244
Cheers guys. The lens I was thinking of is the PENTAX DA* SMC 200MM F2.8 ED (IF) SDM which is their latest incarnation of the lens - I think the DA's are not for the full frame sensor but could be wrong there.

Thanks for the link to the LMC pic - nice, bit of fringing but I'm probably not going to get away without some fringing in the price bracket I can afford. I've got the Sigma 70-300 (supposedly APO) that will stay at f4.5 at 200mm - I'll give that a whirl in the next week and see how it goes. No noticeable CA in the daytime shots - it's real impressive for a little over $200.
Reply With Quote
  #6  
Old 11-12-2014, 07:00 PM
gregbradley's Avatar
gregbradley
Registered User

gregbradley is offline
 
Join Date: Feb 2006
Location: Sydney
Posts: 17,877
The Pentax 6x7 165mm F2.8 is very cheap and no fringing.

http://www.pbase.com/gregbradley/image/137896676

Greg.
Reply With Quote
Reply

Bookmarks

Thread Tools
Rate This Thread
Rate This Thread:

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off

Forum Jump


All times are GMT +10. The time is now 07:14 PM.

Powered by vBulletin Version 3.8.7 | Copyright ©2000 - 2024, Jelsoft Enterprises Ltd.
Advertisement
Testar
Advertisement
Bintel
Advertisement