Infinity focus on 18-135
Posted 26/10/2011 - 17:40
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I can tell you the review sample I had showed no problem focusing on infinity. I wouldn't expect there to be a problem so you may have a faulty and/or damaged lens.
Best regards, John
Posted 26/10/2011 - 17:59
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I wonder if others can confirm /refute what John said above.
It can focus on clouds, but if the sky is completely blue it won't focus.
Similarly, won't focus on a uniformly cream coloured wall 6-7 feet away.
Otherwise, I can't fault the lens.
It can focus on clouds, but if the sky is completely blue it won't focus.
Similarly, won't focus on a uniformly cream coloured wall 6-7 feet away.
Otherwise, I can't fault the lens.
Discovering the joys of photography with Pentax
Posted 26/10/2011 - 18:05
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It won't focus on blue sky or on a uniform cream wall and I wouldn't expect any AF lens to do so. AF needs contrast and detail to work.
Best regards, John
Posted 26/10/2011 - 18:33
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Err
My DA 18-55 WR and Sigma 10-20 does, so did my DA*300
My DA 18-55 WR and Sigma 10-20 does, so did my DA*300
Discovering the joys of photography with Pentax
Posted 26/10/2011 - 18:44
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As John has said low contrast subjects are not the best to test the AF of a lens, at any distance. However I have a Pentax 50-135 away for repair at the moment that stopped locking on to focus at infinity. According to the repairer it worked fine on his calibration machine, but not on my K5 and K20. It has been returned again and is awaiting parts to adjust the calibration.
Barrie - Too Old To Die Young
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Posted 26/10/2011 - 19:19
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If you can wait until tomorrow I'll give mine a try. I can't say I have noticed any problems at infinity, but I tend not to try to focus on blue sky or blank walls.
Posted 26/10/2011 - 19:30
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Hmm, I have noticed that some or all of my lenses don't focus on blue sky. I however never pay attention to it and just focus on something else that has a bit of contrast. Sorry, I don't have a 18-135 to test.
Pentax K10D + Vivitar 55/2.8 macro + Super Takumar 55/1.8 + SuperMultiCoated Takumar 85/1.8 + SuperMultiCoated Takumar 135/3.5 + SuperMultiCoated Takumar 200/4 + Super Takumar 300/4
Pentax K100D + DA18-55ALII + DA55-300
Pentax K5 + FA31Ltd + M50/1.7 + DFA100WR + M120/2.8 (+ DA18-55WR at occasion)
Pentax K100D + DA18-55ALII + DA55-300
Pentax K5 + FA31Ltd + M50/1.7 + DFA100WR + M120/2.8 (+ DA18-55WR at occasion)
Posted 26/10/2011 - 21:12
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DaveN wrote:
My DA 18-55 WR and Sigma 10-20 does, so did my DA*300
I'm amazed by this. I've never had a lens that will focus reliably on featureless anything at all, be it sky, wall, cloth, or anything else.My DA 18-55 WR and Sigma 10-20 does, so did my DA*300
You're saying you actually get 'green hexagon' focus confirmation, pointing the camera at uniform, featureless, blue sky????
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Pentax K-3, DA18-135, DA35 F2.4, DA17-70, DA55-300, FA28-200, A50 F1.7, A100 F4 Macro, A400 F5.6, Sigma 10-20 EXDC, 50-500 F4.5-6.3 APO DG OS Samsung flash SEF-54PZF(x2)
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Pentax K-3, DA18-135, DA35 F2.4, DA17-70, DA55-300, FA28-200, A50 F1.7, A100 F4 Macro, A400 F5.6, Sigma 10-20 EXDC, 50-500 F4.5-6.3 APO DG OS Samsung flash SEF-54PZF(x2)
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Posted 26/10/2011 - 21:36
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As long as it works the other way round..... from blue sky
to earth it should be OK!
to earth it should be OK!
Half Man... Half Pentax ... Half Cucumber
Pentax K-1 + K-5 and some other stuff
Algi
Pentax K-1 + K-5 and some other stuff
Algi
Posted 26/10/2011 - 21:46
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Oops, actually they have a infinity hard stop which the 18-135 does not
Discovering the joys of photography with Pentax
Posted 26/10/2011 - 21:52
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DaveN wrote:
Oops, actually they have a infinity hard stop which the 18-135 does not
True, but you'll still find that with many lenses, the hard stop at the infinity end of the focus throw is actually beyond infinity.Oops, actually they have a infinity hard stop which the 18-135 does not
The green hexagon at the bottom of the viewfinder is the only way of knowing whether the camera has confirmed that it has focused.
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Pentax K-3, DA18-135, DA35 F2.4, DA17-70, DA55-300, FA28-200, A50 F1.7, A100 F4 Macro, A400 F5.6, Sigma 10-20 EXDC, 50-500 F4.5-6.3 APO DG OS Samsung flash SEF-54PZF(x2)
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Pentax K-3, DA18-135, DA35 F2.4, DA17-70, DA55-300, FA28-200, A50 F1.7, A100 F4 Macro, A400 F5.6, Sigma 10-20 EXDC, 50-500 F4.5-6.3 APO DG OS Samsung flash SEF-54PZF(x2)
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Posted 26/10/2011 - 21:56
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Actually, I use my sigma 10-20 almost exclusively on MF and hard focused to infinity
Discovering the joys of photography with Pentax
Posted 26/10/2011 - 22:26
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DaveN wrote:
Actually, I use my sigma 10-20 almost exclusively on MF and hard focused to infinity
Well yes, but the depth of field is enormous with extreme wide angle lenses.Actually, I use my sigma 10-20 almost exclusively on MF and hard focused to infinity
If you're going to use a lens as a fixed focus lens and rely on DOF, you'd be better off setting the focus to the hyperfocal distance.
Not the same thing at all as actually being focused on infinity, and nor is turning the focus ring as far as it will go.
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Pentax K-3, DA18-135, DA35 F2.4, DA17-70, DA55-300, FA28-200, A50 F1.7, A100 F4 Macro, A400 F5.6, Sigma 10-20 EXDC, 50-500 F4.5-6.3 APO DG OS Samsung flash SEF-54PZF(x2)
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Pentax K-3, DA18-135, DA35 F2.4, DA17-70, DA55-300, FA28-200, A50 F1.7, A100 F4 Macro, A400 F5.6, Sigma 10-20 EXDC, 50-500 F4.5-6.3 APO DG OS Samsung flash SEF-54PZF(x2)
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Posted 26/10/2011 - 23:53
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Probably your best target for infinity focus would be the moon?
Matt
Shooting the Welsh Wilderness with K-m, KX, MX, ME Super and assorted lenses.
Shooting the Welsh Wilderness with K-m, KX, MX, ME Super and assorted lenses.
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237 posts
15 years
In the sky
If you have this lens can you confirm if this is the same for you?