Pentax AutoFocus Drive
Jan 27, 2016 13:40:55 #
My Pentax K3 (under extended warranty) will be 2 years old in April. It has just required replacement of the "AF drive block" for autofocusing and related shutter curtain problems. 1) Has anyone out there had AF focus block problems with their camera,regardless of brand? 2) What would be the life expectancy of a drive block? 3) Am I correct to assume that usage contributes to drive failure - I use my camera almost daily and do use burst as well as 4-5 exposure frames when doing HDR. Thanks, for any info.
Jan 28, 2016 13:19:16 #
PAToGraphy wrote:
My Pentax K3 (under extended warranty) will be 2 y... (show quote)
Pat, I have a K-3 also, but have not experienced any problems at all.
I suspect that the AF drive block is the mechanical screw drive that is used for AF lenses that lack their own drive motor (as opposed to Pentax SDM or DC motor lenses). As a mechanical item, it will have a life expectancy that will be shortened by high usage. However, there may have been something else amiss if the shutter mechanism also needed work as opposed to a wear related failure. Unless you have a very high shutter count, I would look at the failure as an anomaly.
I would suggest that you pose this question on the Pentax Forum as you will have much better response there. Best wishes.
Jan 28, 2016 17:49:44 #
I too have had no problems with my K3, but your experience makes me glad I got the extended warranty.
Jan 28, 2016 21:00:49 #
lsimpkins wrote:
Pat, I have a K-3 also, but have not experienced a... (show quote)
Thank you this is my second Pentax with a motor problem. I need to look up my ,ens that I use most often - a tamron autofocus. All others are pentax. I do have high shutter counts and use my camera almost daily. Searched the Pentax forum and found nothing. I will try posting in it. (I have trouble finding my way around it) Appreciate your response.
Jan 28, 2016 21:02:57 #
tomw wrote:
I too have had no problems with my K3, but your experience makes me glad I got the extended warranty.
Because if similar experience with my K5, I got the extended warranty and am very glad. I wrote to pentax and asked about life expectancy and "burn out factors". Tech said they hadn't had any "memos" come through about these being a problem....I am really thinking it is high usage.
Jan 28, 2016 21:59:24 #
Jan 28, 2016 23:05:51 #
PAToGraphy wrote:
Thank you this is my second Pentax with a motor problem. I need to look up my ,ens that I use most often - a tamron autofocus. All others are pentax. I do have high shutter counts and use my camera almost daily. Searched the Pentax forum and found nothing. I will try posting in it. (I have trouble finding my way around it) Appreciate your response.
Your two Pentax lenses (assuming your signature info to be current) and the Tamron are all screw drive focusing as opposed to internal motor lenses. So the AF drive in the camera body is used for every shot.
As another poster asked, how high is your shutter count? I believe that the shutter is rated for 200,000 actuations.
Just be careful that you don't inadvertently hold (or create drag on) the focus ring on your lenses while using AF. The focus ring rotates on both the Pentax lenses - I don't know about the Tamron.
Jan 28, 2016 23:26:20 #
Martax wrote:
What is your shutter count?
Thanks for reply just checked and shutter count is 25,847 and average "expectancy" = 100,000 (Shuttercount.com)
Jan 28, 2016 23:32:58 #
lsimpkins wrote:
Your two Pentax lenses (assuming your signature in... (show quote)
My tamron is the only non Pentax and it is the one I use the most. It is an 18-200 Aspherical LD XR DiII (IF) f3.5-6.3) Macro. I thought it had an internal motor (the IF) but I am not savvy in lens lingo. It is the lens that is always on my camera and if the internal motor is the morot that drives the lens, that could be the major factor. I've caught myself with the focus rings and have to be careful. This lens has a lock and there have been times when I have forgotten to unlock it - another factor creating strain.
So, I really appreciate your comments. WIll try and post in Pentax forum tomorrow.
Jan 29, 2016 00:43:53 #
PAToGraphy wrote:
My tamron is the only non Pentax and it is the one I use the most. It is an 18-200 Aspherical LD XR DiII (IF) f3.5-6.3) Macro. I thought it had an internal motor (the IF) but I am not savvy in lens lingo.
Actually the IF just means internal focus. According to the Tamron website, only the Nikon mount version of this lens has an internal focus motor.
Jan 29, 2016 09:00:17 #
lsimpkins wrote:
Actually the IF just means internal focus. According to the Tamron website, only the Nikon mount version of this lens has an internal focus motor.
Thanks for the explanation. I thought IF (internal focus) meant it would have an internal motor. I didn't catch that when I read through the Tamron site. Really appreciate your response.
Jan 29, 2016 09:30:18 #
PAToGraphy wrote:
Thanks for the explanation. I thought IF (internal focus) meant it would have an internal motor. I didn't catch that when I read through the Tamron site. Really appreciate your response.
Internal focus::: the fact that focusing is all done WITHIN the fixed tube of the lens. In other words that lens does not physically(externally) get longer or shorter when zooming in or out. Lens length(body of lens) does not change "outside dimensions. Is that clear? I hope, clear and accurate.?? RJM
Jan 29, 2016 09:52:38 #
digit-up wrote:
Internal focus::: the fact that focusing is all done WITHIN the fixed tube of the lens. In other words that lens does not physically(externally) get longer or shorter when zooming in or out. Lens length(body of lens) does not change "outside dimensions. Is that clear? I hope, clear and accurate.?? RJM
Clear, thanks. I read, but can't always "translate" into what practical meaning - but I am learning. I find lenses confusing!
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