My Review of the Pentax HD-DFA 28-105mm f3.5-5.6 Zoom Lens.

Full frame. See 100% detail crop just below...

After looking over a fair number of images from the 28-105mm Pentax lens, when used in tandem with the K-1 body, I've come to the conclusion that it's a really good lens and if you decide to embrace Pentax's vision of a full frame camera system this might be the lens to buy. It's not the fastest of the Pentax full frame zooms being offered but it does have the most usable focal length range and it doesn't mind being used wide open, at its maximum apertures. 

Let's start with a physical description of the lens: It's small for a lens that cover the 24-36mm film gate but it feels dense, and heavier than expected, when you pick it up. It does not have an external aperture ring so you'll always be using one of the camera controls to set your f-stop. The filter ring at the front of the lens is 62mm and the supplied cap is the pinch type and it's made of thick plastic; not thin or chintzy stuff. The lens is supplied with a cloth pouch and a petal-type lens hood  that can be reversed onto the front of the lens for transportation. Please don't be a dweeb and shoot with the lens hood reversed. It just doesn't make any sense at all. If you are too lazy to use the lens hood you should just throw it away. Anything else looks lame.

There is a small, almost vestigial focusing ring positioned closest to the the back end of the lens (the camera side) and I can't imagine wanting to use it instead of the AF in one of the K series cameras. The front ring is a very long (from front to back of the lens) zoom ring which has a nice rubber grip. Focal lengths are marked on the grip at 28,35, 50, 70, 90 and 105mm. 

In deciphering the lens description from the lens barrel markings the "HD" stands for high definition and means that the lens was constructed and coated to work with high resolution digital sensors. The D-FA means it's a digital lens that covers the full 24x36mm frame. ED connotes the use of extra low dispersion glass in the optical construction while "WR" means that the lens has been made weather resistant with the application of gasketing. Finally, the lens is "DC" which means it has built in motors and doesn't depend on noisy "screw-driver" mechanical connections to the camera in order to focus.

The lens features a nine bladed, rounded aperture which generally means better bokeh, and I have found this to be the case at nearly every focal length and focusing distance. The lens weighs in at 1.33 pounds and has an optical construction of 15 elements in 11 groups. Included are two precision aspherical elements, an ED element and an anomalous dispersion element. A bit more sophisticated than a typical "kit" lens, for sure. 

I've been shooting with it in low light situations and also in bright sunlight (trying to achieve maximum performance with the lowest ISOs) and have been able to rely on the maximum apertures to delivery good to great performance (best at the wider angles but still good at the long end). I've had very little flare even in flare prone shooting situations and when I stop down one stop the performance of the lens equals that of my 24-105mm f4.0 Panasonic Lumix lens at the same f-stops; and that lens is nearly three times the price of the Lumix. The only real advantage of the Lumix lens over the Pentax is the constant aperture and a closer minimum focusing distance. 

The Pentax 28-105mm trombones (extends) as you zoom but the focusing is internal. Even fully extended, at 105mm, the barrel and extensions are tight and not at all anxiety provoking. The lens inspires confidence because it feels "right" mechanically. 

I selected this lens over the available Pentax 24-70mm f2.8 because I value the focal length range of the 28-105 more than I do the extra stop at the middle of the range or the extra two stops at the longest end. If I need shallower depth of field at the 100-105mm range I have the Pentax 100mm macro lens which is an f f2.8 and which is nicely sharp and contrasty even when used wide open. The 28-105 is just a great walking around lens for 90% of the imaging most people would do. By adding the 50mm f1.4 FA and the longer 100mm macro along with the zoom I feel like there's not a lot of general photography I can't cover well. Additionally, the K-1, at 36 megapixels, gives me room to crop and fine tune. 

The camera and lens work in concert with the camera applying lens corrections to Jpeg files and writing the corrections into the raw files. The camera is making some obvious corrects to lens geometry but once made they are largely unnoticeable and I'd rather have the camera correcting them than spend time doing it myself. Of course, I would prefer a lens that didn't require computational (my new buzz phrase) corrections but I'll gladly trade that compromise for a lens that is nicely sharp, contrasty, has great color and is fun and easy to carry around. And that's the 28-105. I'd buy it again as long as my intention was to use it with a Pentax K-1 or K-1 mk2 body. More samples below: 
100% crop from the image above the written review.

It's a smartphone world and we're now elitists photographers of the first order....

It's fun to get out of town, travel, and see how stuff gets done in public in other cities/countries. Since college students are back in school, and young families have finished with their vacations and are back at school and work, the travel scene in early October looks to be a bit.... gray. Almost geriatric. Especially in a city like Montreal which appeals to people who like to see old stuff. Which isn't all bad since the people around you at tourist sites aren't generally getting blind drunk, screaming at the top of their lungs, diving off rooftops or whining for juice boxes and attention. The crowds we encountered in Montreal; from museums to historic plazas, were mostly comprised of tourists over 50 years old and moving slowly.

In one way this seemed to tilt my usual nearly subconscious, but always running, "camera count" a bit further toward "many DSLRs" and away from "completely overrun by smartphone cameras." Up to a point the older the male person in the crowd was the more likely he was to sport at least one DSLR or mirrorless, interchangeable lens camera. Habit? Training? Taste? Or a discomfort with the operational feel of using a smartphone for a primary camera? I'm going to guess that it's a liberal helping of all four factors.

Women over 50 in the crowd seemed equally likely to be sporting either a phone or a traditional camera, and sometimes both. One with which to shoot for posterity and the other for immediate visual communication with family, via Facebook, et al.

I've got to say though that there were a few times when I tried to get a perfect shot with my traditional DSLR camera, got frustrated because of things like a contrast range wider than the Grand Canyon, and ended up pulling out my iPhone XR to see if it could do a better job. In cases like dark interiors with vaulted ceilings the phone won; hands down. Why? Its processor is making calculations so quickly that it seems to be pulling some exposure components for the shadows and some to control for highlight burnout. It's creating images that are almost like HDR without even being set to HDR. That, and the fact that the image stabilization in the phone is phenomenal. There is some computational magic going on in the newest phones that allows them to punch far beyond their weight and into "Wow!" territory.

With a big exterior shot with lots of detail, the full frame, 36 megapixel camera was a clear winner. And the look of the files was......visually sexier.

It's true that the iPhones and decent Android phones have more or less taken the place of point and shoot cameras (with the exception of Belinda and her G15) and they've done so for the same reason that mirrorless cameras are becoming more and more popular = the user can see exactly what they will be getting when they make the exposure by looking at the rear screen. It's an image that has all the settings baked in and set. All the user needs to do is like the image and actuate the "shutter." Chances are the final result will match their pre-chimped image very closely. And that's a comforting thing. Pre-shot-previewing is faster and more sure than the old way of praying you'd get a shot right, reviewing it after the fact and then hoping you'd get another chance to do better. Added to this is the fact that the screens on the newer phones are bigger, brighter and much more detailed than the cameras most user are transitioning from.

We'll keep shooting traditional gear for most stuff but...the writing on the wall is becoming clearer all the time. When sensors in phones get bigger it's armageddon for traditional camera makers.... At least for the use case of travel and tourism. I know, I know, you're the one guy out of a million who shoots sports and can't work without a 1200mm lens on a full frame body that shoots at least 10 (mechanical) frames per second. You'll have to wait for the next generation of phones....

The man in the center was both tour guide and the person who would quickly take each person's cell phone, line up a shot with the phone's owner in front of a cathedral and snap a few shots. 
He is doing it factory style, grabbing for a new "camera" with his right hand while handing back the "camera" just used. It's efficient; I'll give him that...

one of each.

And we complain that cameras are too big?

My favorite photography location in Montreal. Of course it would encompass food and (unrecorded) coffee.

There is a food market in Montreal that I found to be very much fun to visit, look at, photograph and play in. We took the Metro to the Jean-Talon stop on Tuesday morning, then walked a few blocks more to find the outdoor market. As the weather was still in the 50's and the day was sunny and nice, there were no winter walls up, no space heaters, no big coats to lug around. The whole market was wide open, breezy and top lit by hard daylight diffused through the white tent tops. As I understand it, the market at Jean-Talon is the biggest (and nicest) open air market in the city. Regular people flock here to buy the freshest produce, specialty foods, and things like maple syrup candies. The place is spotless, welcoming and a wonderful riot of color. 

We got to the market around 9:30 in the morning and started walking slowly through row after row of produce, flowers, and cheeses. I was hesitant at first to just snap away with my camera so I slid into my picture taking slowly to gauge how welcome or unwelcome it would be. In the markets in San Antonio there are even signs at vendor stalls attempting to forbid photography. It was definitely not the case in Montreal, at Jean Talon. I felt welcome everywhere. Especially so if I took the time to greet the vendor and smile. We struck up conversations with a young man who grew up in Calgary and suggested a car trip from Calgary through the mountains to Vancouver (sounds great). Belinda chatted for a while in Spanish with a vendor who moved to Canada from Guatemala about 20 years ago. He gave us hot peppers to take home (coals to Newcastle?). We spoke to a women who came from the south of France to follow her fiancé. They're moving back to France after he gets his degree... We spoke to the shopkeeper who made me one of the finest cappuccinos I've ever had. The conversation was universal; all about how friends change and vanish after they get married and have kids.

Each person we engaged with gave us samples, told us stories and suggested interesting places to see. I should have taken notes so I'd be prepared on our next trip back.

My camera and lens choice of the day was predictable: the only camera I brought was a Pentax K-1 (no back-up!!!!!) and I had a choice of only two lenses. I brought the 28-105mm for the day and it was beyond perfect. I'm just getting a handle on how sharp and snappy that zoom lens is. It's one of the best performing standard zooms I've used. I can see that the camera is making some big corrections for distortion and vignetting but with a 36 megapixel sensor there's a lot of information available to manipulate and I haven't seen a downside to the "computational" correction of the lens's few faults. 

Everything in this post was done with that lens. From close ups to more distant shots, it just flat out works. After spending the two previous days with this particular camera in my hands I find I've gotten used to it much more quickly than I anticipated. Pentax offers some weird controls and weird features but you don't have to use them. You can use the camera in the most straightforward fashion and never get bogged down with menus.

I actually gave up being a control freak for a while and used a mode setting that's marked, "TAV." It's essentially the same as having Auto-ISO in manual mode. You set the aperture you want and the shutter speed you think is best and the camera attempts to change the ISO to provide correct exposures. It's fun and mostly accurate but I often find myself wanting images that are darker than normal so I can mess with them without them breaking down in post production.

So, without further ado, here is my small gallery of initial takes from the Jean-Talon market. 

Belinda achieves mastery of the Canon G15. I tried to get her to 
take along the Fuji X-E3 and the 18-55mm but she says, 

It's too big.