The 5 Lens Autofocus Drive Types Explained

Pentax AF technologoy overview and comparison

By beholder3 in Articles and Tips on Aug 19, 2018

Camera lenses today use many different technologies to facilitate autofocus.  Under the hood, there needs to be some way for the camera to move elements inside the lens, which in turn changes what's in focus.  In this article, we'll be taking a look at the different types of focusing implementations currently in use by Pentax.  In addition, you'll learn more about some of the terminology used by Pentax and other manufacturers.

Pentax users currently have access to both manual focus lenses and lenses with one of 5 different autofocus drive technologies. 

These have evolved over many years, and as almost everything in life, each comes with its pros and cons.  For example, fast focusing in single autofocus mode (AF.S) is not the same as fast continuous autofocus (AF.C).  In-lens motors can fail.  Gears in drive mechanisms can shatter.  Powerful motors take up space.  Modern, larger drives allow more torque.  The list goes on!

It is important to stress from the very beginning that many of the designations given to the drive types (e.g. SDM or DC) are generalizations. Different lens models can have different autofocus implementations even if they go by the same name.  Ultimately, this can mean that a drive type that is commonly known to be fast may actually appear slow in a certain lens and much quicker in another.

Pentax Astrotracer Guide and GPS Feature Comparison

A look at the O-GPS1 versus in-camera GPS

By K David in Articles and Tips on May 10, 2018

Pentax cameras offer GPS functionality in two ways: either through the built-in antenna found in the Pentax K-1, K-1 II, and K-3 II, or through the O-GPS1 accessory, which works with most other DSLRs since 2010.

Sample 78-second star photo taken with the Astrotracer

GPS data unlocks another unique Pentax DSLR feature: the Astrotracer.  With the help of location information and the Shake Reduction system, the camera can track stars by turning the sensor to match the stars' movement.  This allows you to more than double the exposure time of astro photos without introducing star trails— which can result in more detailed starscapes!

While this is great, it gives rise to a number of questions:

  • What are the practical exposure time limits of the Astrotracer?
  • How do you optimize the Astrotracer's performance?
  • What is the difference between in-camera GPS functionality and cameras using the O-GPS1?
  • Can I use the O-GPS1 on GPS-enabled cameras?

We answer these questions and more through a series on hands on tests.  Read on for the answers!

Pentax Astrotracer Guide & O-GPS1 vs In-camera GPS Comparison

Weather / Storm Photography Tips and Tricks

By Black Mesa Images in Articles and Tips on Mar 26, 2018

In the Northern Hemisphere, springtime is right around the corner.  Here in the High Plains of the United States, that means thunderstorm season.  Due to the nature of weather photography, it can be confusing for the beginner.  Here are some of the tips and tricks that I have learned over the last several years capturing thunderstorms.

Polarr, a Mobile Editing Alternative - Part 2

A look under the hood - including a few surprises

By babywriter in Articles and Tips on Mar 21, 2018

In Part One, we did a quick walk around of the Polarr app. This photo editing software, available for virtually every major computing platform, promises a full-featured experience, even on mobile devices. But does it deliver on that promise? Let’s go under the hood and find out.

Polarr, a Mobile Editing Alternative - Part 1

A photo editor for all seasons - and platforms

By babywriter in Articles and Tips on Mar 7, 2018

Adobe’s Lightroom/Photoshop combination are the undisputed market leaders in photo editing and organizing on the desktop. Both are extremely powerful and versatile, have a devoted following, and online tutorials and enhancements are legion.

Sometimes, however, that kind of power is overkill. Increasingly, photographers are editing on the go with a phone or tablet, and posting straight to an online service like Instagram. Adobe has recognized this change and has fielded mobile versions in response, but their caution in this space - and their insistence on a Creative Cloud subscription for full functionality - has opened up the field for other, more nimble competitors. The app stores of MacOS, iOS, and Android are filled with ambitious editing applications, many of which give Lightroom Mobile a run for its money.

Polarr Photo Editor (or, more simply, Polarr) is one of these.

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