Forgot Password
Pentax Camera Forums Home
 

Reply
Show Printable Version Search this Thread
12-10-2007, 02:04 PM   #1
Senior Member




Join Date: Jun 2007
Location: Tennessee
Photos: Gallery
Posts: 112
Pentax 18-250 lens sliding

Hello:

I have the Pentax DA 18-250 lens and was wondering if the lens is supposed to slide out or in when you tilt the camera down or up? I've not had this happen with other makers and didn't know if I had a bad lens, or if it is supposed to be that way.

Tks!

Connie

P.S. I've got a question into PentaxImaging, but haven't rec'd a response yet.


Last edited by ctt; 12-10-2007 at 02:05 PM. Reason: spelling
12-10-2007, 02:23 PM   #2
Site Supporter




Join Date: Mar 2007
Location: Los Angeles, CA
Photos: Albums
Posts: 389
People call that "zoom creep" and it happens on some lenses. I believe the 18-250mm has a zoom lock switch to help against zoom creep.
12-10-2007, 02:29 PM   #3
ctt
Senior Member




Join Date: Jun 2007
Location: Tennessee
Photos: Gallery
Posts: 112
Original Poster
You are absolutely correct! I found it! Tks!

Connie
12-10-2007, 02:49 PM   #4
Veteran Member
ericc's Avatar

Join Date: Sep 2006
Location: Western Oklahoma
Posts: 406
It's a common feature on Tamron super-zooms. My 28-300 has the same lock. Since the DA 18-250 is a rebadged Tamron, it has the lock on it. My 28-300 doesn't creep that much. My old Tokina 28-105 was notorious about it.

12-10-2007, 06:12 PM   #5
Inactive Account




Join Date: Jul 2007
Location: London
Posts: 1,067
Hi Connie

When grabbing the camera in a hurry and quickly attempting to manually zoom-in on something, occasionally it is all too easy to forget that the switch of your Pentax 18-250mm lens has been left in the 'locked' position. If you ever feel the slightest resistance when handling the 'zoom ring', DO NOT on any account try to FORCE the 'collar' of the lens with the switch locked-on, otherwise you may do serious damage to the internal mechanism of the lens........simply stop and then check to ensure that you have fully disengaged the 'lock' switch BEFORE doing anything else !

With best regards
Richard

P.S. Has Glen Miller hit town yet ?

Last edited by Confused; 12-10-2007 at 06:30 PM.
12-11-2007, 07:06 AM   #6
Junior Member
dvdman45's Avatar

Join Date: Nov 2007
Location: Elliot Lake, Ontario Canada
Photos: Gallery
Posts: 46
Sliding

Yes I find this sliding of the lens is a "downfall"...especially when trying to focus downward.
This is my first dslr (K10D) and I love it. AND, now a new learning curve starts.
12-11-2007, 07:31 AM   #7
Pentaxian
Lowell Goudge's Avatar

Join Date: Jan 2007
Location: Toronto
Photos: Gallery | Albums
Posts: 15,400
Sliding has been a problem as long as there have been single ring zooms. That is the only real complaint I have with my Vivitar Series 1 70-210 f/3.5, and also what prompted me to get a dedicated macro, because realistically that is about the only time the lens is pointed strait down.

The other thing to watch out for, and I admit I don't know the specific lens you are talking about, is the lens weight cantilevered out from the camera body when mounting on a tripod. My Series 1 has no tripod mount and in the early 80's the lens weight (almost 2 pounds) was enough to distort many cameras causing loss of power, when mounted on the camera's tripod socket.
12-11-2007, 07:59 AM   #8
Inactive Account




Join Date: Jul 2007
Location: London
Posts: 1,067
Hi Lowell

I wholly agree with you when you said:

QuoteQuote:
The other thing to watch out for.......is the lens weight cantilevered out from the camera body when mounting on a tripod. My Series 1 has no tripod mount and in the early 80's the lens weight (almost 2 pounds) was enough to distort many cameras causing loss of power, when mounted on the camera's tripod socket.
I also own a Vivitar Series 1 70-210mm zoom fitted with an OM-mount and often used to have to remember to firmly tighten the head of the tripod BEFORE attaching this lens to the SLR body, otherwise you could almost guarantee that tripod instability would ensue !!!

Best regards
Richard


Last edited by Confused; 12-11-2007 at 01:25 PM.
12-11-2007, 11:53 AM   #9
Forum Member
TheWengler's Avatar

Join Date: Nov 2007
Location: Brisbane, CA
Posts: 79
QuoteOriginally posted by ctt Quote
I have the Pentax DA 18-250 lens and was wondering if the lens is supposed to slide out or in when you tilt the camera down or up? I've not had this happen with other makers and didn't know if I had a bad lens, or if it is supposed to be that way.
I've heard of this problem before. However, I've also seen many reviews where users say that there is no creep at all and the zoom lock isn't needed. There must be some inconsistency there in production.
12-11-2007, 12:09 PM   #10
Pentaxian
Lowell Goudge's Avatar

Join Date: Jan 2007
Location: Toronto
Photos: Gallery | Albums
Posts: 15,400
QuoteOriginally posted by TheWengler Quote
I've heard of this problem before. However, I've also seen many reviews where users say that there is no creep at all and the zoom lock isn't needed. There must be some inconsistency there in production.
try hot and cold also, we are dealing here with the consistency of lubricants as well! I have had 2 absolutely identical and totally different behaving single collar zooms in the past. Don't sweat it. if it has a collar lock, use it it is good practice, because you can be sure it will really slip the one time you don't want it to
12-11-2007, 01:18 PM   #11
Inactive Account




Join Date: Jul 2007
Location: London
Posts: 1,067
Hi TheWengler

Re your point:

QuoteQuote:
I've also seen many reviews where users say that there is no creep at all and the zoom lock isn't needed. There must be some inconsistency there in production.
If you support or 'cup' this lens in the palm of your hand, keeping it fairly level horizontally (with the lock-switch 'off'), I've found that lens-creep doesn't happen. However, if you let the camera & lens dangle from your neck under it's own weight with the lock-switch 'off', that's when problems may occur. In this instance, just slide the lock-switch into position and lens-creep disappears. You just have to get into the habit of using the switch !

Bst regards
Richard
Reply

Bookmarks
  • Submit Thread to Facebook Facebook
  • Submit Thread to Twitter Twitter
  • Submit Thread to Digg Digg
Tags - Make this thread easier to find by adding keywords to it!
k-mount, lens, pentax, pentax 18-250 lens, pentax lens, slr lens
Thread Tools Search this Thread
Search this Thread:

Advanced Search


Similar Threads
Thread Thread Starter Forum Replies Last Post
Pentax K-x: something inside sliding when tipping the camera 90 degree up-right? yuwlyuwl Troubleshooting and Beginner Help 15 01-16-2011 12:38 AM
Is the Pentax or Tamron 18-250 a parfocal lens? BobG Pentax SLR Lens Discussion 7 01-11-2009 08:45 PM
Comments on K20 with Pentax 18-250 lens Human Pentax DSLR Discussion 0 07-12-2008 12:53 AM
Pentax Problem with Flash and lens 18-250 spmarion Pentax DSLR Discussion 3 03-22-2008 04:55 AM
Lens decision: Pentax 16-45 and 50-200 combo OR 18-250? sweetpapa Pentax SLR Lens Discussion 30 12-07-2007 02:12 PM



All times are GMT -7. The time now is 02:50 PM. | See also: NikonForums.com, CanonForums.com part of our network of photo forums!
  • Red (Default)
  • Green
  • Gray
  • Dark
  • Dark Yellow
  • Dark Blue
  • Old Red
  • Old Green
  • Old Gray
  • Dial-Up Style
Hello! It's great to see you back on the forum! Have you considered joining the community?
register
Creating a FREE ACCOUNT takes under a minute, removes ads, and lets you post! [Dismiss]
Top