Last Updated on August 22, 2021
The Pentax 645 will appeal mainly to DSLR or 35mm SLR shooters. The 645’s shooting experience is similar, the price of entry is very reasonable, and the results can be amazing for anyone just getting into medium format. Sure, a Lomography Diana is way cheaper (and admittedly a whole bunch of lo-fi fun), but for a camera you can grow into and actually use in a professional setting, the Pentax 645 is your best option.
Name and film formats: The camera produces negatives that measure 6 centimeters by 4.5 centimeters, hence the name: the Pentax 645. The camera can shoot 120 film (the most common today), 220 film (much less common), and 70mm film (not at all common now). You’ll get 15 shots from a roll of 120.
Dates: Introduced June 1984 and eventually replaced by the Pentax 645n in 1997, a commendable 13-year run. So any 645 you buy today could be as old as Metallica’s thrash masterpiece Ride the Lightning or as new as Radiohead’s groundbreaking OK Computer…which is still pretty damn old, especially for a camera. Like those albums, the Pentax 645 is still totally worth adding to your collection.
Current cost and availability: Six years ago, I paid $168 for the body, grip, and caps from KEH. A 120 film insert was $62 from the awesome used section at Roberts Camera, and a 75mm lens cost me $50 from some fellow on eBay. So all together, a complete kit in excellent shape set me back only $280. Today, the same kit could cost as much as $350 to $400, which is still an amazing bargain. Although the 645 is not as ubiquitous as Pentax’s 35mm K1000, deals definitely abound for patient buyers: you won’t have to hunt for long if you want one in good shape at a price that makes your wallet happy.
Autofocus: Nope, the 645 is a manual focus camera. If you want autofocus, pick up either the 645n or 645nii and an autofocusing lens. Those autofocusing models, however, will definitely cost much more.
Lens mount: Pentax’s 645 A mount. There are a bunch of lens options available at really good prices now, especially if you stick to the manual-focus series, the “SMC Pentax-A 645.” The great thing is that you can use those lenses on Pentax’s other medium-format 645 cameras if you decide to upgrade, even digital cameras like the 645D and 645Z.
Batteries: 6 AAs in the grip. It’s awesome that such a cheap and readily available battery is used, but they do make the camera heavier.
Weight: And speaking of heavy, yeah, the Pentax 645 is a proper chunky monkey. The body, grip, and film insert weigh 46.2 ounces or 1,309 grams or 2.88 pounds according to the manual. But with batteries and a standard 75mm f/2.8 lens added, the kit tops out at 3.8 pounds according to my scale. That’s still not impossibly heavy of course (just about the same weight as Canon’s 1DX Mark III with battery and a 50mm f/1.4 lens), but the Pentax’s large, boxy, and bulky body magnifies the overall chunk factor. If Canon’s 1D series is a sleek sports car, Pentax’s 645 is a lumbering cargo van.
Light meter: Yes, it has one—a classic center-weighted pattern that produces nice exposures. It works in all the main shooting modes the camera offers: program, aperture priority, shutter priority, and manual.
Max shutter speed: 1/1000. That max speed is pretty typical of film cameras from the ‘70s and ‘80s, but it’s quite slow compared to digital cameras today. If you are shooting in bright light with fast film, you probably won’t be able to shoot wide open. In manual mode, the shutter speed can be adjusted in whole stops only. There is something refreshingly simple about being limited to whole stops, but for serious work on slide film, you’ll likely get annoyed.
Flash sync speed: 1/60. Very slow by today’s standards.
Film advance and rewind: Both are automatic and pretty quick for an ‘80s camera. The downside is that both are also very loud, so you won’t be able to sneak any street shots.
Continuous shooting: Yes, but the 645 is not a speed demon by any means. It shoots a mere 1.5 frames a second in continuous mode. Frankly, I hadn’t tried it until I started putting this review together, and I wish I hadn’t even bothered. It’s ultimately a nightmare of noise and wastefulness. For anyone shooting landscapes or portraits (which you probably are if you are interested in this camera), just save your film.
User manual: Like all film cameras, the Pentax 645 has a number of idiosyncrasies and old-timey irritations waiting for the uninitiated. I’ll go through some of them here, but grab a PDF of the manual from Butkus when you want an even deeper dive into the camera.
Tons of people started their film photography journey with a Pentax K1000 (even Drew Barrymore rocks one), but digital shooting over the past couple of decades has been dominated by Canon, Sony, Fuji, and Nikon—companies that have shaped contemporary photography with oftentimes bold and innovate gear. Pre-2000s, Pentax produced some pretty revolutionary stuff too. When the 645 camera appeared in 1984, for example, Pentax was attempting to create a new market at the intersection of image quality, automation, and affordability.
I mean, check out this particularly voluminous ad.
“One of a new kind,” Pentax insisted, but perhaps the better slogan would have been, “The best of all possible worlds.” Want great images? The 645 offers medium-format excellence. Need a camera that is easy to shoot? The 645 boasts motor-driven film advance and rewind as well as the autoexposure abilities of your dad’s 35mm camera. Don’t have a ton of cash? The 645 is way cheaper than any Hasselblad.
Even sports shooters were encouraged to get in on the goodness.
These days, shooting sports with the 645’s meager 1.5 frames a second prob seems a nonstarter, but medium-format magic combined with some still-modern conveniences? Yes, please. Take my money.
Just How Big Is the Pentax 645?
Really big. It might be the hugest huge you have ever seen in a handheld camera. Here is what the 645 looks like next to a regular old 35mm SLR.
As you can see from the pic above, the lens mount and mirror are gigantic. The area is substantially larger than 35mm film or full-frame digital sensors. It’s also larger than most modern medium-format digital sensors (e.g., Fuji’s GFX series or Pentax’s 645d and 645z).
The increased bulk and heft, however, are totally worth it if you also want giant and luscious negatives. Here is a size comparison between a strip of medium format and 35mm negatives.
Film Inserts and Loading Film
Unlike most every 35mm camera, the Pentax 645 uses film inserts that you first have to remove from the camera and then load with film. Here is the back of the 645 with the insert in place and then the insert itself removed and with no film.
These inserts are not swappable mid-roll (like with Hasselblad’s mightily awesome camera system). Once you’ve loaded an insert with film, you have to shoot the entire roll before removing it. That is a bummer for sure, but you can’t have it all at the Pentax’s wallet-friendly price point. The 120 inserts can run close to $100 each now, and each will give you only 15 or 16 shots. 220 film inserts are still pretty easy to find and are less expensive these days, but the rolls cost more to develop and scan if you aren’t doing it yourself.
The first time I loaded film in an insert, I was a total fumbling idiot. It’s not actually hard to do, but it does take some getting used to. So no worries if it ends up a mess for you too.
To begin, get your film out of the wrapper.
Then insert the roll on the side with the red S on the spool retainer.
Grab the film leader and stretch the film across the insert. Make sure the black side of the film is facing up. If you see paper instead, you’ve put the roll in the wrong way. Thread the leader through one of the slots in the spool.
Tighten up the film by rotating the silver wheel thingy shown in the pic here.
Keep rotating until the Start arrows align with the red S and the red line.
You are now ready to pop the insert back into the camera.
Lenses and Crop Factors
Pentax’s original A-mount lenses for the 645 are mechanically fantastic—super solid construction, butter smooth focus throw, and clicky aperture rings. Optically they are good too, but there is nothing faster than f/2.8.
If you grew up on 35mm film or full-frame sensors like I did, the focal lengths for medium format lenses might be mystifying at first. Multiply by 0.62 to get a 35mm equivalent. Because math sucks, here is a handy table.
|Pentax 645 Lens||35mm Equivalent|
|35mm||21mm (21.7mm actual)|
|45mm||28mm (27.9mm actual)|
|55mm||35mm (34.1mm actual)|
|75mm||45mm (46.5mm actual)|
|120mm||75mm (74.4mm actual)|
|150mm||90mm (93mm actual)|
|200mm||125mm (124mm actual)|
|300mm||180mm (186mm actual)|
|400mm||250mm (248mm actual)|
The really good news is that the old, manual-focusing 645 lenses will also work just fine on Pentax’s new digital medium-format cameras. The sensors though are actually smaller than traditional medium-format film, so multiply by 0.79 for a 35mm equivalent. Because math still sucks, here is another handy table.
|Pentax 645 Lens (on a digital body)||35mm Equivalent|
|35mm||28mm (27.65mm actual)|
|45mm||35mm (35.55mm actual)|
|55mm||45mm (43.45mm actual)|
|75mm||60mm (59.25mm actual)|
|120mm||90mm (94.8mm actual)|
|150mm||120mm (118.5mm actual)|
|200mm||160mm (158mm actual)|
|300mm||250mm (237mm actual)|
|400mm||300mm (316mm actual)|