One of my lenses doesn't focus well

Tex · 01-16-2011, 07:56 AM

I have two bodies (K20 & K100DS).

I shoot sports with the K20 so I keep a Tamron 200 on it all the time. It shoots sharp images.

My K100 is my daily all around camera. I alternate between a few lenses. It always shoots sharp images.

I have a Sigma 20-40 f/2.8 that I use when I need a fast wide lens. It is a good lens and has always shot well on the K100.

The last couple of times I have used it on the K20 the images just aren't sharp.

The lens moves, so the AF is working. It seems to try and focus.

This is the only combination that seems to produce OOF images.

As my K100 gets older it will probably get retired and the K20 will move down and make room for a new body. So having all my lenses work well is important.

Is there something obvious that I am missing?

I have not tried to adjust the focus on the K20. Does it link to just one lens or affect all lenses?

JeffJS · 01-16-2011, 09:36 AM

It's possible that the camera needs an adjustment. Without seeing the photos in question, that's about the only thing I'm going to come up with.. You can do it for up to 20 different lenses. As long as you are adjusting a Single lens (both sliders show) and not apply all it will only be applied to that lens. IF the camera (this is an assumption) the camera thinks another lens is the Same lens, it will apply the settings to that lens too.

01-16-2011, 07:56 AM	#1
Tex New Member Join Date: Jan 2009 Location: Texas Posts: 14	One of my lenses doesn't focus well I have two bodies (K20 & K100DS). I shoot sports with the K20 so I keep a Tamron 200 on it all the time. It shoots sharp images. My K100 is my daily all around camera. I alternate between a few lenses. It always shoots sharp images. I have a Sigma 20-40 f/2.8 that I use when I need a fast wide lens. It is a good lens and has always shot well on the K100. The last couple of times I have used it on the K20 the images just aren't sharp. The lens moves, so the AF is working. It seems to try and focus. This is the only combination that seems to produce OOF images. As my K100 gets older it will probably get retired and the K20 will move down and make room for a new body. So having all my lenses work well is important. Is there something obvious that I am missing? I have not tried to adjust the focus on the K20. Does it link to just one lens or affect all lenses?

Similar Threads
Thread	Thread Starter	Forum	Replies	Last Post
10 Reasons why manual focus primes are better than those new auto focus zoom lenses	JoepLX3	Pentax SLR Lens Discussion	188	07-25-2012 03:28 PM
Do you use only manual focus lenses?Do a lot of folks use only manual lenses?	heralu	Pentax DSLR Discussion	12	01-05-2011 04:06 PM
K5 Focus Confirmation with MF Lenses	martin s	Pentax K-5 & K-5 II	1	11-12-2010 07:23 AM
How can different lenses have different focus adjustments?	GregK8	Pentax DSLR Discussion	11	08-19-2010 10:01 AM
Using trap focus with AF lenses.	barondla	Pentax DSLR Discussion	3	09-11-2006 09:28 AM

01-16-2011, 09:36 AM	#2
JeffJS Inactive Account Join Date: Aug 2008 Location: Michigan, USA Photos: Gallery \| Albums Posts: 7,484	It's possible that the camera needs an adjustment. Without seeing the photos in question, that's about the only thing I'm going to come up with.. You can do it for up to 20 different lenses. As long as you are adjusting a Single lens (both sliders show) and not apply all it will only be applied to that lens. IF the camera (this is an assumption) the camera thinks another lens is the Same lens, it will apply the settings to that lens too.