How to Modify the DA* 60-250mm F4 for Full Frame

By bdery in Articles and Tips on Nov 5, 2017

Pentax’s K-mount has one of the most comprehensive APS-C lens lineups on the market. On the other hand, the digital-era full frame line-up is growing but still small. With the release of the Pentax K-1, many users have taken to testing APS-C lenses to see if they can, in fact, be used on full frame.

With its zoom range, fixed aperture and excellent image quality, the Pentax DA* 60-250mm F4 is a lens that many photographers would have liked to see working on full frame. Sadly, using it in full frame mode without modification leads to dark corners at the wide end and fully black corners at the tele end, as you can see here.

The culprit is a flange on the rear baffle of the lens. Easily accessible, this baffle can be removed, modified or replaced to allow full frame operation.

In this article, we present a step-by-step method to modify the lens, as well as various options to replace the baffle. We also test thoroughly the lens’s optical performance after the modification to evaluate the impact of the change.

Is the modification worth it? Can the 60-250mm be used reliably in full frame mode? Read on to find out!

Modifying the DA* 60-250mm F4 for Full Frame

Mobile Photo Editing: Snapseed for Beginners

User friendly photo-editing app for your phone or tablet

By Jeff Lopez in Articles and Tips on Oct 5, 2017

Snapseed is a user friendly photo-editing application currently developed by Google. It has a very comprehensive layout, which at first handles very differently to other popular photo editing apps, but in time you will probably begin to like it a lot. Although it's not up to the magical prowesses of desktop imaging editors, like Adobe Lightroom and CaptureOne, it certainly holds up it own in terms of versatility and power to these, and I would say it is the best mobile photography editor in Google Play. This article does not pretend to be a full tutorial, it is mostly focused on a beginner's approach to it, yet there will be some examples that explore some really good "pro" wise features that will be useful as we learn to use it. Before anything, I must mention that this review is based on the Snapseed Android version, (Samsung Galaxy Note 4, Android 6) and the examples will be JPG. Recently Snapseed added basic RAW support (as of version 2.17), but RAW file management is very poor. It needs some very complicated workarounds which I prefer not to discuss inside the article.

Guide: DSLR Lens Resolution Testing at Home

Using freeware programs and charts

By beholder3 in Articles and Tips on Sep 21, 2017

Many enthusiasts spend a lot of money on camera gear and then want to know how good it is. While every experienced photographer can tell the optical qualities of a lens from fitting sample images there are ways beyond subjective quality evaluations. These are about testing lens sharpness and resolution using either an optical bench (which costs more than the average new car, so not really a good fit for "homegrown" testing), or shooting test charts and analyzing the results mathematically.

The article is about the latter: resolution testing at home using freely available test charts and software to analyze it.

DSLR Guide for Shooting Sports II: Horse Racing

How to set up autofocus and other DSLR settings

By beholder3 in Articles and Tips on Sep 11, 2017

Horse Racing

In our second article on how to shoot sports type subjects with Pentax gear we will again try to showcase one way to approach a certain type of subject scenario. The previous article can be found here: Guide to Camera and Autofocus Settings for Shooting Sports.

Again this is intended to get interested users going quicker and to provide an easy reference for you, regardless if you use a Pentax, Canon, or Nikon DSLR. Most of the tips in this article should help you out with shooting sports, perhaps after converting some Pentax-specific terms.

Astrophotography Part 6 of 6: Reducing Image Noise

Tips for Reducing Noise

By K David in Articles and Tips on Aug 11, 2017

High-quality digital cameras with good high-ISO performance combined with fast, high-quality optics from makers like Pentax, Samyang, Sigma, and Tamron are taking astrophotography out of the enclaves of astronomers and putting it in the hands of hobbyists, too. This six-part series examines various elements of astrophotography.

This article looks at ways to reduce noise in digital images. Using best capture practices, software, and editing techniques, a significant amount of noise can be removed from overnight photos.

To revisit the rest of the articles in this series, here are links and their subjects:

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