The Firing Line Forums

Go Back   The Firing Line Forums > The Skunkworks > Gear and Accessories

Thread Tools Search this Thread
Old January 16, 2011, 08:26 AM   #1
Senior Member
Join Date: July 19, 2010
Posts: 192
Parallax Adjustment question

I see some scopes have a front of the tube adjustment for the objective lense and some have a side knob to adjust the objective lens.

I have also read that the front adjustable objective will be clearer and brighter than the side knob adjustable(assuming the same glass) due to fewer lenses and such inside the tube.

If so, how much brighter and clearer.

I am thinking that with my diabetic eyesight, I might get a good scope with adjustable objective. Looking at all options at this point.

What would be advantages/disadvantages of either.

Thanks in advance.

Last edited by dontcatchmany; January 16, 2011 at 08:36 AM.
dontcatchmany is offline  
Old January 16, 2011, 12:55 PM   #2
Bud Helms
Join Date: December 31, 1999
Location: Middle Georgia
Posts: 13,155
I am told the side knob adjustment had a "finer" adjustment to it, but the front ring type locks down more solid, and has fewer parts. 'Haven't actually ever handled the side knob type, so I haven't been able to personally compare them side-by-side.
"The irony of the Information Age is that it has given new respectability to uninformed opinion." - John Lawton, speaking to the American Association of Broadcast Journalists in 1995
Bud Helms is offline  
Old January 19, 2011, 11:45 AM   #3
Senior Member
Join Date: August 7, 2000
Location: Floating down the James River in VA
Posts: 2,599
Bud is right, except that adjustable objectives typically have a finer adjustment than side parallax/side focus adjustment. I've owned both,and have never had a problem with adjusting either.
Also, side focus/side parallax adjustments allows a smaller objective bell diameter for the same size lens,allowing you to mount the scope slightly lower, and they allow use of flip up Butler Creek type scope caps, which a rotating AO makes difficult to use..

Typically the brightness difference between the two types isn't a practical issue,because most scope makers sell either AOs or side focus in a given line, rather than both types,preventing a direct comparison. Get the scope that looks brightest to you.
Poodleshooter is offline  
Old January 19, 2011, 12:40 PM   #4
Senior Member
Join Date: July 19, 2010
Posts: 192
Thanks folks.

Looking at Zeiss Conquest 4.5-14x44 AO MC with Rapid Z 600 reticle.
dontcatchmany is offline  
Old January 20, 2011, 11:37 PM   #5
Senior Member
Join Date: January 27, 2010
Location: AR
Posts: 1,390
I find the side adjustment very convenient looking down the barrel, particularily if the scope is rather long. I have grown to like them.
chiefr is offline  
Old January 24, 2011, 09:04 PM   #6
Senior Member
Join Date: May 14, 2009
Location: colorado
Posts: 281
I bought the zeiss myself just over a year ago. Although others seem to have better results than I did I was very upset with it in low light. It gets dark quickly and almost seems to get blurry. In full light it is the finest scope I have ever owned.
I pulled it off and went back to the Leupold VXIII 3.5x10 I was using before.
On the plus side it gave me an excuse to get a new rifle and now sits on a .270WSM dedicated to antelope hunting where low light is not usually a problem.
I have the Z800 that matches perfectly with that round.
liberty1 is offline  

Thread Tools Search this Thread
Search this Thread:

Advanced Search

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 -5. The time now is 10:20 AM.

Powered by vBulletin® Version 3.8.7
Copyright ©2000 - 2017, vBulletin Solutions, Inc.
This site and contents, including all posts, Copyright © 1998-2017 S.W.A.T. Magazine
Copyright Complaints: Please direct DMCA Takedown Notices to the registered agent:
Contact Us
Page generated in 0.05331 seconds with 9 queries