[lesmore49]

This whole thing came about because the discussion was to get the 28-105. But I already have the 24-70 and 70-200. I couldn't see what advantage to now include the 28-105 as I could put the K1 in crop mode and achieve 105 without changing lenses. Anyways, That's what I do..for better or worse. Yep, they are both Tanks, I don't mind.

If I had the 24-70 and the 70-200 as you do, I wouldn't bother getting the 28-105. For the most part the fact that you have your full frame camera with a 24-70 while on full frame is fine. Then you have the 70-200, which I understand in an excellent portrait lens. If you're planning to take mostly portraits at a particular time, I would use the 70-200...you have a very good range of 'portraitable' (to coin an awkward phrase) focal lengths within that lens...70...to 105 and beyond...all at your zoom hand.

If your doing some general walking around at some event..or just walking around...the 24-70 is your pick. Wide angle to moderate telephoto and everything in between and yes if you want more reach at the top end, just switch to cropped frame and you have 105mm at our disposal.

Nope, I don't see any reason for you to buy a 28-105...with the 24-70 and 70-200. You've got it all in that range and both those lenses are fast F stoppers and quality lenses that cover a wide range of focal length.

[Paul the Sunman]

Yep, they are both Tanks, I don't mind.

I have plenty of DFA "tanks": The DFA* 70-200, DFA 15-30, DFA 150-450, and the DFA* 50 on order. But the "light-weight" DFA28-105 is my walk around zoom, and most used lens by far. It goes everywhere with me, the others are packed only for specific tasks. If I need wider, the 15-30 goes in the bag.

The DFA 24-70 is not on my to-buy list.

[awscreo]

I personally might rent the 24-70 and see for myself. Seems opinions differ in that lens (and the rant on conterpart), mainly regarding the corner sharpness. My 28-105 is extremely well balanced in terms of frame sharpness at f8-11 which I mainly use, so 24-70 really has to at least match that, and be decently sharp wide open for low light / portraits for me to switch to it.

[bm75]

But I already have the 24-70 and 70-200. I couldn't see what advantage to now include the 28-105 And as I could put the K1 in crop mode and achieve 105 without changing lenses. Anyways, That's what I do..for better or worse.

ok nothing wrong with that if the IQ suits your requirements. 36 mpx cropped to APS C still deliver 15 mpx images; FWIW that's a fair amount of detail remaining. But remember: it's just a cropped image , not an image taken with a lens the same FF correspondent FL. Just that.

i have the same problem: I have got 24-70 70-200 but mt preferred lens is the 24-35 f/2 sigma (for walkaround or cityscapes). My solution is a small inexpensive mirrorless with Pentax and Nikon legacy primes , I don't like switching lenses often with my primary camera body. I do that if I need a wider FOW than 24 on FF. the second camera is also useful when my primary camera is on the tripod: it acts like a scout camera, there's always something to discover when your first camera is busy or you wouldn't want to waste time fidding with lens swtiching. I found IQ pretty comparable and there's nothing to loose.

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Last edited by bm75; 12-10-2018 at 09:26 PM.

[DeadJohn]

This whole thing came about because the discussion was to get the 28-105. But I already have the 24-70 and 70-200. I couldn't see what advantage to now include the 28-105 And as I could put the K1 in crop mode and achieve 105 without changing lenses. Anyways, That's what I do..for better or worse. Yep, they are both Tanks, I don't mind.

In that context, if you already have the 24-70 there's no need to add the 28-105. The only benefits would be if you wanted a lighter lens or if you frequently needed the 70-105 range.

70mm cropped is *not* the same as 105mm. It's a similar field of view but you ignore half the pixels on your sensor. If you still have enough resolution and images are low noise enough, sure, go ahead and use crop mode and you can get good photos.

[pschlute]

This whole thing came about because the discussion was to get the 28-105. But I already have the 24-70 and 70-200. I couldn't see what advantage to now include the 28-105 And as I could put the K1 in crop mode and achieve 105 without changing lenses. Anyways, That's what I do..for better or worse. Yep, they are both Tanks, I don't mind.

One advantage is the 28-105 is a lighter lens to carry. So it could deserve a place in your camera bag based on that.

Just to be clear, on the K1 + 24-70 at 70mm putting the camera in crop mode will not give you any greater magnification. The lens produces the same sized image circle irrespective of FF/aps-c setting. You will have a narrower field of view and the image straight from the camera will show an apparent magnification, but that is only because you have "enlarged" that smaller field of view more. You would get the exact same result by using the FF mode and cropping the picture in pp.

If you feel you need the magnification of a 105mm lens there is only one way to get it...buy a 105mm lens. Given what you have already I don't think you need to.

[mikesbike]

Well, nothing beats having f/2.8 when you need f/2.8 for low light, faster shutter speeds, reduced DOF, etc. as long as quality is there. When you need it, you need it. if you don't have those needs, why pay the extra cost and carry the extra weight? Especially if the quality is still there. Additionally, I don't see much wrong in using the K-1's crop mode to achieve the same framing at 70mm that an APS-C camera body would provide, doing so conveniently without having to change lenses. This is why Pentax designed this feature into the K-1. It is a very attractive feature. I am still happy with the results I get from my K-5 IIs, and the K-1's crop mode will deliver similar resolution.

[Papa_Joe]

If you just want to know, if a 28-105 makes sense. Just grab one of the plenty leagcy lenses and try it out, at nearly no cost. You might as well try an 35 - 135 or something like this. If you do not like the results, sell the lens for the same price. Worst case is you will stick to a 28-105 for $ 99 (or less) while having those two expensive ones.

[Rondec]

The biggest reasons to get the 24-70 are f2.8 constant aperture and the 24-28mm range. The reasons to get the 28-105 are smaller size, 70-105 range, and cheaper price. Both are nice lenses. My wife shoots weddings and needs the faster aperture and I like to shoot landscapes and like having the ability to go to 24mm on the focal length.

I will say that the biggest negative to me on the 28-105 is the variable aperture. It's slower by two stops on the long end than the 24-70 and if you do much indoor photography, that could be a deal breaker -- even with the beautiful high iso capability of the K-1.

As far as the whole cropping thing, that is neither here nor there. You could just as easily say that you don't don't need a 150mm lens if buy the 28-105 because you can crop the long end to 150mm.

[niblue]

For me having 24mm is much more worthwhile than having 105mm in a walkabout lens, which is why I'm using a Sigma 24-70mm F2.8 as the walkabout lens on my K1.

I used to own a Sigma 24-135mm F2.8-4 in my film days and might see if I can get hold of one of those as I think it'd be good as a lightweight FF walk-about lens.