Up until the last decade, if you needed a wide angle prime for your Pentax 645, there was only one game in town...the legendary 35mm f3.5. It can be had in either manual or auto focus variations. With the release of Pentax's digital line of the 645, modern offerings of 25mm super wides became available. Though, both iterations were quickly, and mysteriously, discontinued. Only rumors from supply chain failures to poor construction circulate on the web. These lenses are now rare and expensive, and besides, 15mm equivalent focal length is a bit too wide for most field applications. For a complete summary of the film vs digital focal lengths, check out my conversion chart.
There are also zooms that can cover the wide focal range, such as the 28-45mm, but there are people that like the advantages a prime offers and will never want the zoom (you all know who you are).
Even though the third generation of this lens just came out, I decided to go with the used manual version. I find that auto focus doesn't add enough to a wide angle used primarily for landscape work. Manual focus, on the other hand, adds the benefit of an infinite focus stop. This can be very useful in low light and night shooting. I'll admit, this is a feature I miss on my modern Nikkor glass.
THREE GENERATIONS OF 35's:
- Pentax-A 35mm f3.5 - Manual Focus
- Pentax-FA 35mm f3.5 - Autofocus
- Pentax-D FA 35mm f3.5 - Autofocus w/Updated Elements
- 9 Elements | 8 Groups
- Filter Ø = 77mm
- Min Focus = 0.3m
- Weight = 470g
- Length = 67mm
First thing you notice is that this lens is well built. There is heft, solid construction, and smooth actuation of all moving components. The focus ring is fluid and precise. There is nice damping, but since the barrel is stout, focus glides easily in and out. Overall, this is a true work of cosmetic and mechanical perfection.
In practice, this lens is a joy to use. It's perfectly balanced on the 645 body making it comfortable to hand hold. It also uses a standard 77mm front filter thread. Future iterations of this lens increased this to 82mm, which drives filter prices sky high. I've used a variety of filter combinations, including the lee filter holder and 105mm polarizer at the end with no vignetting.
Resolution is outstanding. The 100% crop of sunrise over Johnson Lake, Great Basin National Park shows this. Scanned on the flatbed Epson V850 with sharpening setting at low. Shots have came out with crisp, with great color rendering. I do not have any frames drum scanned (yet), but scans have been rich in detail.
Distortion has not been a problem either. Pretty spectacular performance for such a wide field of view.
I can not recommend this wide angle enough. It definitely has lived up to it's reputation. I've enjoyed it's performance so much, that I use it on my Nikon bodies as well! It is a bit shocking how well a retrofocus lens this wide handles. Images shot on medium format have a nice 3D rendering that are similar to my Schneider 47mm Super-Angulon XL on 6x9. For traveling in the mountains, there's not much that this little prime and the 120mm macro can't handle together. I was worried I would be left wanting something wider or better with Pentax's newer lenses, but this lens's abilities have put this concern to rest.