AF Adjustment AF Defocus AF Predictor in the Pentax exif - meaning?

yucafrita · 09-20-2020, 05:31 AM

Simple question: what do AF Adjustment, AF Defocus, AF Predictor in the Pentax exif stand for?

I imagine AF Adjustment is clear but Defocus and Predictor?

I struggle to find an satisfying explanation on the forum or the web for it.

Thanks!

SharkyCA · 09-20-2020, 08:40 AM

Hi Yucafrita, you may be able to find the answer here!
ExifTool by Phil Harvey

yucafrita · 09-20-2020, 09:37 AM

Well, it lists the tags but doesnt explain them

stevebrot · 09-20-2020, 10:35 AM - **1 Like**

Originally posted by yucafrita

Well, it lists the tags but doesnt explain them

There are no actual tag names in the makernotes, just values. The tag names were assigned by the ExifTool developers* and are their best guess as to a value's purpose. Many of the tags in the Pentax makernotes remain fairly cryptic with opaque significance. I too have wondered about the AF Defocus and AF Predictor tags, but have not been curious enough to do a deep dive. You might be able to get an answer by joining the ExifTool forum and posing the question there.

Steve

* As a result, there is some variance between ExifTool and software that uses ExifTool and the labels attached by other products such as Pentax DCU.

leekil · 09-21-2020, 10:12 AM - **2 Likes**

Originally posted by yucafrita

Well, it lists the tags but doesnt explain them

You could mess around with it and try and figure it out.

It's discussed here, but no definitive conclusion AF Info in EXIF useful for anything?

09-20-2020, 05:31 AM	#1
yucafrita Veteran Member Join Date: Oct 2015 Posts: 459	AF Adjustment AF Defocus AF Predictor in the Pentax exif - meaning? Simple question: what do AF Adjustment, AF Defocus, AF Predictor in the Pentax exif stand for? I imagine AF Adjustment is clear but Defocus and Predictor? I struggle to find an satisfying explanation on the forum or the web for it. Thanks!

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09-20-2020, 08:40 AM	#2
SharkyCA Pentaxian Join Date: Sep 2017 Location: Carleton Place, Ontario, Canada Photos: Gallery Posts: 806	Hi Yucafrita, you may be able to find the answer here! ExifTool by Phil Harvey

09-20-2020, 09:37 AM	#3
yucafrita Veteran Member Join Date: Oct 2015 Posts: 459 Original Poster	Well, it lists the tags but doesnt explain them

09-20-2020, 10:35 AM - 1 Like	#4
stevebrot Otis Memorial Pentaxian Join Date: Mar 2007 Location: Vancouver (USA) Photos: Gallery \| Albums Posts: 42,007	Originally posted by yucafrita Well, it lists the tags but doesnt explain them There are no actual tag names in the makernotes, just values. The tag names were assigned by the ExifTool developers* and are their best guess as to a value's purpose. Many of the tags in the Pentax makernotes remain fairly cryptic with opaque significance. I too have wondered about the AF Defocus and AF Predictor tags, but have not been curious enough to do a deep dive. You might be able to get an answer by joining the ExifTool forum and posing the question there. Steve * As a result, there is some variance between ExifTool and software that uses ExifTool and the labels attached by other products such as Pentax DCU.

09-21-2020, 10:12 AM - 2 Likes	#5
leekil Pentaxian Join Date: May 2016 Photos: Albums Posts: 2,003	Originally posted by yucafrita Well, it lists the tags but doesnt explain them You could mess around with it and try and figure it out. It's discussed here, but no definitive conclusion AF Info in EXIF useful for anything?