Pentax 645z Part I

Gear / February 28, 2018

Growing up in the film age I learned photography basics on a Canon AE-1 my father had used many years before. A child of the 80’s I quickly jumped aboard the path to auto winding film, auto exposure and auto focus as quickly as I could. This all seemed like the path to the future until I picked up my first medium format camera a Mamiya RB67. It was love at first sight, the perspective it offered, the quality it offered even the way it made you work and the pace you had to dedicate yourself to.

The digital age came soon after and I abandoned the dark room and the RB for Canon digital cameras, as happy as I was with the digital workflow even back in the late 90’s, I didn’t even look back to see what I was missing for many years to come. Digital advancement in those early years was amazing and we quickly went from 6MP to 12P to 24MP and I loved the quality bumps along with the mega pixels bumps as the years went on.

It was about four years ago that I started having that hankering for medium format quality and feel again but with the astronomical price of medium format digital back in 2013 there was just no way it was going to work for me, $30k was too steep a price. It took a year or so until my hope for medium format stated coming alive with news of the Pentax 645Z and about another year until It was released and I had sold off all of my Canon gear to scrape enough cash up to pick one up.

Say hello to the Pentax 645z so many good things in such a big package. I seem to have an odd obsession with doubling megapixels 6,12,24,51 and let me tell you 51 is a pretty sweet spot but by itself it’s not enough, you need good dynamic range, great high iso support and great lens selection. The Z delivers on a lot of these things you need in order to hold up the promise of 51MP image greatness and a full camera system.

Sensor Quality

Dynamic Range

The Z has been tested to about 15 stops of dynamic range but that only tells half the story, the Z for it’s great range on a properly exposed file really excels when you accidentally under/over expose an image and you have to recover your mistake. So long as you do this on a RAW file which I will assume you all to be doing you can pretty easily recover workable images with a 3-5 stop over/under exposure on a normal image. Highlights and shadows may clip as is natural but you’ll have something workable and with very little abnormal noise. This is truly amazing!

High ISO

The Z has some big advantages here sensor size divided by megapixels gives you bigger pixel size, bigger pixels capture more light, more light results in less noise. With the Z I’ve been able to shoot with ISO 12,800 and 25,000 with printable results, head and shoulders above anything else I’ve ever had the ability to shoot with.

Lens Selection

The third leg of the tripod for any great camera system are the lenses, this is unfortunately where we start to fall down with the Z. 51MP requires great modern lens selections and Pentax has left us with but a few good choices along with many of the old Pentax 645 lenses from the film systems of past. I’ve built my system with a mix of old and new and get great results but I feel let down by the lack of new, waterproof, silent motor modern digital lenses.


The Z in my opinon shines in this area in most ways, firstly it’s not designed to be a new camera style where it’s design over function. Buttons are the best thing on a camera, something tactile you can find in the dark of night shooting the stars and something you can gain muscle memory in finding the setting you need without taking you eye off the subject. Using the camera is the biggest part of this, but there are other things to consider too, weight, size, ergonomics in the hand etc. The Z is good in most of these ways, it’s buttons and dials are smart (mirror lockup dial) and many many buttons that you can customize. It’s also a relic of a past age where you had to have a huge dimension from lens mount to sensor to get the optics to work out. Pentax for all the good they did here didn’t update the camera to enter the 21st century and it shows in many many ways.

Stay Tuned for Part II