Forgot Password
Pentax Camera Forums Home
 

Reply
Show Printable Version Search this Thread
08-30-2008, 01:16 AM   #1
Inactive Account




Join Date: May 2008
Location: Melbourne
Posts: 1
K20D: Getting 300 mm f2.8 to work on it

I'm thinking of buying a K20D with the intention of using my m/f Pentax 300 mm f2.8 and 500 mm f4.5 lenses. Went to local camera shop to demo it and there appears to be no communication between camera and lens. Shows "F' in top display, won't shoot. Three staff members couldn't work it out, but I think they weren't Pentax experts.

Any suggestions? Am I missing something here?

08-30-2008, 01:30 AM   #2
Veteran Member
Taff's Avatar

Join Date: Aug 2008
Location: Perth Western Australia
Photos: Gallery | Albums
Posts: 1,613
are these manual lenses?
08-30-2008, 01:34 AM   #3
Inactive Account




Join Date: Dec 2007
Location: Santa Teresa, New Mexico
Photos: Gallery
Posts: 1,130
QuoteOriginally posted by funinoz Quote

Any suggestions? Am I missing something here?
Read the manual. Pentax Imaging - Manuals & Literature
08-30-2008, 02:12 AM   #4
Veteran Member
ftpaddict's Avatar

Join Date: Jan 2008
Location: Yurp
Photos: Gallery
Posts: 4,669
If they're K or M-series (no "A" position on the aperture ring) K-mount lenses, they feature no electronic contacts on the lens mount, and therefore cannot communicate aperture information to the body.

Your K20D is not set up to allow use of aperture ring with older lenses. You can change that in your camera's custom menu.

Once you enable the appropriate setting, the camera will work properly.

Still, you'll have to twist the aperture ring manually, then press the green button (I think? I 've never owned a K20D), then fire away.

08-30-2008, 02:35 AM   #5
Senior Member
timk's Avatar

Join Date: Jul 2008
Location: plymouth
Photos: Gallery
Posts: 101
dont forget to select manual focus with the lever
08-30-2008, 02:36 AM   #6
Veteran Member
Taff's Avatar

Join Date: Aug 2008
Location: Perth Western Australia
Photos: Gallery | Albums
Posts: 1,613
you got it FTP
08-30-2008, 02:43 AM   #7
Inactive Account




Join Date: Aug 2008
Location: Cape Town, South Africa
Posts: 232
that is correct. Enable the aperture option in the custom menu to not be "Prohibited" or whatever, and set it to manual focus and try again. Im using some embaressingly old lenses on mine.
08-30-2008, 03:21 PM   #8
Syb
Veteran Member
Syb's Avatar

Join Date: Aug 2007
Location: Near Utrecht, Netherlands
Photos: Gallery
Posts: 1,224
The 300/2.8 (if we're talking just Pentax here) does not exist in K- or M-edition right? It is only in A-mode.

The thing may be that you did not switch the lens to A-mode. This, combined with the customer menu option to forbid use of aperture ring, may have caused your problem.

Don't know about the 500/4.5

Good luck!

08-30-2008, 06:42 PM   #9
Senior Member
TomE's Avatar

Join Date: Sep 2006
Posts: 299
There is not A 500mm 4.5 Pentax lens only the manual version that doesn't stop down automatically since the rear of the lens comes off to allow the use of 49mm filters.

Tom
08-31-2008, 02:11 PM   #10
Veteran Member




Join Date: Jun 2008
Location: Guatemala
Posts: 338
QuoteOriginally posted by timk Quote
dont forget to select manual focus with the lever
I prefer AF-C for focus confirmation, not sure how the k20d works though.
08-31-2008, 08:35 PM   #11
Loyal Site Supporter
Canada_Rockies's Avatar

Join Date: Nov 2007
Location: Sparwood, BC, Canada
Photos: Gallery | Albums
Posts: 9,554
QuoteOriginally posted by nixcamic Quote
I prefer AF-C for focus confirmation, not sure how the k20d works though.
You get focus confirmation in MF mode as well. All three of my Pentax bodies give me confirmation. I tend to use snap-in-focus with my M series lenses at times. Catch the subject as it goes through the focus point automatically if you set the camera to MF.S and hold down the shutter button while keeping the centre focus point on the subject.
08-26-2009, 07:13 AM   #12
Senior Member
trishytee's Avatar

Join Date: Jan 2009
Location: Mandurah Perth
Photos: Gallery | Albums
Posts: 221
Yes I had the same problem. A bit embarrassing really as like you I asked at the local camera shop, and rang a big firm, but it was a PS teacher who told be what was going on. As the lens you are using will be manual you will be actually turning the 'ring' to get the F stop you want. therefore you won't have to see it in the window, it will always be F.......Do what Marlin says and all will be fine. It just won't work automatically.
08-26-2009, 10:05 AM   #13
Site Supporter
pentaxmz's Avatar

Join Date: Dec 2008
Location: Seattle
Posts: 659
QuoteOriginally posted by funinoz Quote
I'm thinking of buying a K20D with the intention of using my m/f Pentax 300 mm f2.8 and 500 mm f4.5 lenses. Went to local camera shop to demo it and there appears to be no communication between camera and lens. Shows "F' in top display, won't shoot. Three staff members couldn't work it out, but I think they weren't Pentax experts.

Any suggestions? Am I missing something here?
I don't think anyone specifically told you the exact place to change this setting, so here you go:

1. Press menu
2. Right arrow to Custom Setting (C)
3. Scroll to page 7/7 or custom setting #36 Using aperture ring
4. Set #36 to #2 Permitted

That's all.
08-26-2009, 10:27 AM   #14
Senior Member
xGene's Avatar

Join Date: Apr 2008
Location: Toronto, Ontario
Posts: 151
QuoteOriginally posted by wlank Quote
What is this?
I find it alarming when someone, especially a Moderator of this forum, takes such a stance. The OP is a new member, seeking advice for an issue that obviously could cost him a pile of cash; takes the time to post in this forum with a legitimate and well articulated request for information...(unless I am mistaken, this forum should be a source for such technical advice), and what he gets in return, from a MODERATOR, no less, is a "...Read the manual..."

What is this???? wlank, whoever you are, is this the way you really want to "moderate" this forum??? Having a bad day??? What kind of first impression this OP will get from this? (in case you don't know, first impressions ARE important...). If this is your "style", maybe you should "moderate" something else.

funinoz, on behalf on the members of this forum, I apologize. Not all Moderators are like this one, on the contrary.

Gene
08-26-2009, 11:02 AM   #15
Pentaxian
Mike.P's Avatar

Join Date: Mar 2008
Location: South Coast .. UK
Photos: Gallery
Posts: 1,758
QuoteOriginally posted by xGene Quote
What is this?
I find it alarming when someone, especially a Moderator of this forum, takes such a stance.
I quite agree, a pretty poor attitude for anyone to take .. never mind a moderator.
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!
camera, dslr, f2.8, k20d, mm, pentax, photography
Thread Tools Search this Thread
Search this Thread:

Advanced Search


Similar Threads
Thread Thread Starter Forum Replies Last Post
How does AF Adjustment work in K20D? brucestrange Troubleshooting and Beginner Help 2 05-08-2010 12:15 PM
8G SD card with K20D... work? janosh Pentax DSLR Discussion 23 06-28-2009 03:04 PM
P67 300/4 EDIF for closeup work? surfotog Pentax Medium Format 11 03-20-2009 10:13 PM
K20D Won't Work with my 50mm SMC 1.7! HELP! PentaxForums-User Pentax SLR Lens Discussion 2 03-08-2009 12:06 AM
DA55-300 + Sunny Day = PhotoBreak at Work! applejax Pentax SLR Lens Discussion 12 06-12-2008 07:16 PM



All times are GMT -7. The time now is 01:11 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