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Pentax 150-450mm AF Speed


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Pentax 150-450mm AF Speed

2 Jun 2015 10:53PM   Views : 738 Unique : 444

Just a short blog today, to add a bit if information regarding the AF speed of the new Pentax 150-450mm, with and without the Pentax 1.4x AF converter.

Subjectively, it didn't seem to make much difference to the speed of AF, so I ran a test using an online stop watch. The time to focus and release the shutter was measured, with the amount of focus travel needed being adjusted after each shot so it was the same. Lots of shots were taken, so operator variation would also even out.

Obviously the actual shutter release delay will depend on many factors, but with the parameters kept the same the only difference was that the first run of shots was lens only and the second run was lens plus converter.

The result was an average delay of 0.3s lens only and also 0.3s using the converter, in other words no difference whatsoever.

The next thing to look at will be image quality with and without, but that will have to be another day. I don't like to leave a blog with no pictures, so let's see if I can find something from the lens that I didn't previously post.




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NeilWigan Avatar
NeilWigan Plus
13 17 16 England
2 Jun 2015 11:07PM
As you know John I don't have this lens but do have a Sigma 150-500 for my Pentax it would be interesting to compare the two for image quality.
johnriley1uk Avatar
2 Jun 2015 11:31PM
We can arrange that Neil, talk soon!

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