Pentax Brings Star Auto Focus to the U.S.

Updating an Old Friend If you had told me back in 2017 that I’d still be getting new firmware and features for my Pentax K1, I’d have said that was crazy talk.  And yet, twice in the last few years, Pentax has added branded new features to my eight year old camera.   The last big update included additional Astrotracer modes which unlocked the sky tracking system for bodies without a GPS module.  Now, Pentax is back with something I’ve only seen on select Olympus bodies and I am very excited.   One of the biggest challenges in astrophotography is nailing focus. Unlike daytime shooting, where autofocus systems have plenty of contrast and light to work with, photographing the night sky requires extreme precision on tiny, distant points of light. Until recently, that meant zooming in with live view, manually turning the focus ring, and hoping you got it right.   Pentax has introduced a solution: Star AF, part of the company’s Astrophoto Assist premium feature package. With Astro AF, the camera can automatically lock onto stars with accuracy far beyond what many of us can achieve reliably on our own.       What is Star AF?   Star AF is a specialized autofocus system designed to focus precisely on stars. Unlike regular AF modes, which can hunt endlessly in the dark, Star AF uses a dedicated algorithm to analyze star points in live view and adjust focus until they’re as sharp as possible.   It’s not instant—it can take 10 to 30 seconds to complete—but when it works, the result is tack-sharp stars ready for long exposures, Milky Way shots, or tracked images with Pentax’s Astrotracer.       How to Purchase and Install Star AF   Star AF is not included by default—it’s part of the Astrophoto Assist premium function available for supported Pentax DSLRs (such as the K-3 Mark III, K-3 III Monochrome, and with newer firmware, the K-1 and K-1 II).   You can read the install instructions directly at Ricoh’s website.  

1. Update FirmwareMake sure your camera has the latest firmware (version 2.20 or newer for the K-3 Mark III, or the latest available update for K-1 / K-1 II).
2. Purchase the Feature
   • Visit Pentax’s premium feature page here.
   • Pricing is $79.99 plus tax as of this writing.
   • You will receive a 2D code as an image via email in 1-7 days according to the website.
   
3. Activate with a Key
   • In your camera menu, navigate to:Setup page 5 → Limited Functions → Star AF
   • Click the green physical button to the right of your screen.
   • The camera will ask you to align the code you received via email from Pentax in the camera’s live view.
   • Follow the onscreen instructions.

                The Milky Way as seen over the Vineyard Sound in Falmouth.  In situations like this, manually focusing on the island lights can be easier than using stars.   How to Use Star AF in the Field   Once activated, Star AF appears as an option in your camera’s AF settings. Here’s the workflow.  You can also refer to Ricoh’s website.  

1. Set up your camera on a tripod with auto focus enabled on the lens.
2. Press the menu button and navigate to Contrast Detection AF > Contrast AF > STAR to enable.
3. Activate your live view.
4. Compose your shot so stars are within the AF area.
5. Press the shutter halfway or use a remote release.
6. The AF area will magnify, and the camera will begin analyzing star points.
7. Wait—focus can take 10–30 seconds.
8. Once locked, the AF box turns green. Do not adjust the lens after this point.
9. Shoot your image using a remote shutter or self-timer to avoid shake.

  If focus fails (the AF box turns red), try reframing slightly or selecting a brighter star.   Assuming you don’t plan on moving around much or your focal distance doesn’t change, now would be a good time to switch back to manual focus and then keep your hands off the lens!    As always, review every image after shooting to ensure you got the focus you are expecting.        Why Star AF is Worth Considering   Astrophotographers know the frustration of slightly missed focus—your Milky Way might look fine on the camera screen but turn out soft once you zoom in on a computer. Star AF virtually eliminates that guesswork, saving both time in the field and heartbreak later.   Benefits include:  

• Precision: Focuses more accurately than manual attempts.
• Convenience: No more endless zoom-and-tweak cycles.
• Reliability: Once locked, focus remains fixed until you reset it.
• Workflow Speed: Particularly useful when teaching workshops or when conditions (cold, wind, fatigue) make manual focusing difficult.

  At $79.99, Star AF is not cheap for a software-only upgrade. But compared to the value of sharp, once-in-a-lifetime shots of the Milky Way, an eclipse, or a rare comet, many photographers will find the investment worthwhile.       Final Thoughts   Star AF won’t replace skill—knowing how to compose, expose, and process night skies is still essential—but it’s a powerful tool to help ensure your stars are tack-sharp. For Pentax users already enjoying Astrotracer and in-body stabilization, Star AF is another example of how Pentax continues to innovate for night photography enthusiasts.   If you’ve ever lost a perfect Milky Way frame to soft focus, Star AF might just be the feature that pays for itself on your very first clear night.   Do you think this is a useful feature?  Let me know in the comments!   See you out there, after dark!  -T