[Wheatridger]

I'm just about ready to take the plunge for a K-1, but my system design concept depends on using this lens as my everyday walkaround lens. That's like what I did in my happy years with a Sony a850. A Minolta 24-85/4 was that camera's constant companion, and they covered every subject that wasn't too dim, close, wide or far away. In Pentax Land, the f 24/50 is the closest equivalent: shorter, but smaller, too.

I didn't want the weight, either. A K-1 with the F 24-50 weighs about the same (1300+ grams) as a K-3 with the DA 16-50, so the lighter lens would make up for the heavier camera body. So please don't try to talk me into a "pro" 2.8 zoom, or I'll start talking about my impending shoulder replacement surgery!

The F24-50 is a rare lens, but I've stockpiled a few of them. I plan to keep the best and sell the rest. I love the results on my K5IIs. But has anyone used this lens with the new K-1, that's the question?

[Adam]

If anything, I'd try to talk to in to the D FA 28-105mm. Not much heavier (pretty darn light for a 28-105mm with WR), really good optically, and full of the latest tech.

I haven't been particularly impressed by non-star F and FA zooms such as the 28-105, 35-70, and 35-105, but I haven't tried the 24-50mm yet.

[Wheatridger]

That's a logical suggestion, but you've just raised my entry price by $500. If the F 24-50 won't do, that would be my next step... but 28mm isn't 24mm.

Most folks haven't tried the F 24-50. There's never more than one for sale at eBay, and PF readers haven't reviewed one in years. I have an F35-105 that's terrible, but my F 35-70 meets that lens' good reputation.

Because of my Sony/Minolta background, I've been though the FF transition period before. Some of us who are financially constrained used a FF body with the best-regarded legacy lenses. Seeing how good those results were, we stopped hankering for the "best glass."

[jatrax]

I have used the F 24-50 (as well as the 35-70 and 35-105) on the K-5 and K-3. My tests with it on the K-1 indicate it is a good fit if you are primarily concerned about weight. However, the DFA 24-70 is clearly sharper and has more contrast. Like you I intended to use the 24-50 on the K-1 and likely still will in some situations but I think newer lenses will show it up. I have not tried the DFA 28-105 but Like @Adam I think that would be your best solution unless budget prevents it.

[pres589]

There's this guy, which is out of production, and I've never touched. Reviews decently, for the few reviews that are here, and there are probably other places to look; Sigma 24-60mm F2.8 EX DG Lens Reviews - Sigma Lenses - Pentax Lens Review Database

[surfar]

The F24-50mm is good as is the F35-70, as is the A 28-135 and A 35-105.Are they as good as the BIG $$$ DFAs? I cant answer that one because I'm not buying them.( budget)!
When the new 55-300 gets to OZ, i'll consider that one.Thats when the K1s video switch gets turned on!(it works, I tried it for 5 seconds!)

[Wheatridger]

I have used the F 24-50 (as well as the 35-70 and 35-105) on the K-5 and K-3. My tests with it on the K-1 indicate it is a good fit if you are primarily concerned about weight. However, the DFA 24-70 is clearly sharper and has more contrast. Like you I intended to use the 24-50 on the K-1 and likely still will in some situations but I think newer lenses will show it up. I have not tried the DFA 28-105 but Like @Adam I think that would be your best solution unless budget prevents it.

jatrax-- Does the F24-50 lack edge sharpness on FF? Mine is plenty sharp on the K5IIs. As far as contrast goes, I'm usually aiming for less overall contrast in my captures, adding back what I need in post. Or is it the microcontrast that lags?

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Last edited by Wheatridger; 08-19-2016 at 03:05 PM. Reason: terminology improved

[TwoUptons]

I have the A24-50, which I think is optically the same as the F24-50.

It's a good match for the camera in terms of focal length, and it seems a pretty decent lens, though it's not awesome wide open at 24mm, and my 50mm primes kill it on the other end.

Generally, I'd call it as least as good as any of the older 28-80s I've used where they overlap, with the 24mm bonus.

Mine's also easy to mis-focus as it doesn't always agree with the in-finder focus confirmation. I haven't used it extensively with live view, but I expect that will fix it. (As would tweaking the focus, I guess)

I'll admit that this one and my FA28-105 are only until I can afford one of the new lenses... Adam's right; the old zooms aren't as good as the new ones...

-Eric

[Driline]

If anything, I'd try to talk to in to the D FA 28-105mm. Not much heavier (pretty darn light for a 28-105mm with WR), really good optically, and full of the latest tech.

I haven't been particularly impressed by non-star F and FA zooms such as the 28-105, 35-70, and 35-105, but I haven't tried the 24-50mm yet.

That's one all around lens I'd like to get yet.

[jatrax]

Here is a test chart. Click on it to go to Flickr, I have a whole series of shots with various film glass. IMHO, there is nothing wrong with the F 24-50 but the newer glass is better. Honestly I used the 24-50 quite a bit on APS-C and it is fine. If I had not gotten the DFA 24-70 I would be using the 24-50. Anyway, check the charts and judge yourself.

[pcrichmond]

I have the Sigma 24-60 that pres589 mentioned and love it on the K-1 as a general walk around. In fact it performs much better in IQ and front/rear focus issues than it did on the K3. So if you already own the F 24-50 and liked it on FF before, give it a try. The viewfinder on the K-1 is exceptionally bright enough for f4.

[bassek]

I have the Sigma 24-60/2.8, the F35-70 and the F35-105. I prefer the F35-105 on the K-30/K-x especially outdoors but it really doesn't focus close.
The Sigma has a bit cooler colors. Which is not that cool....

Seb

[jatrax]

Thanks. That looks great to me, but I'm not the biggest pixel peeper here. Do you have a 24mm version?

If you click on the image it will take you to Flickr. There is an entire series of images from F series lenses. I shot wide open and f/8 for a range of focal lengths from each zoom. For the 24-50 I think there is 24mm, 35mm and 50mm. To my eye at f/4 the F 24-50 is a bit lacking in contrast, at f/8 it is very good. But check the test shots and see for yourself.

I prefer the F35-105 on the K-30/K-x especially outdoors but it really doesn't focus close.

I also really like the F 35-105 but I mostly do product shots and it does not focus close enough to be practical. As a walk around or general purpose lens it is very nice.

[Wheatridger]

Thanks, jatrax! That's a fine resource. After a quick look, I conclude that my experience is ratified: older 2:1 f4 zooms can be very good to excellent at every setting. More ambitious ones can be lacking. My 35-105 lens has shown some of the myopic haze shown in your test charts. I'll try stopping down.

What I'm looking for is the FF equivalent of the 20-40 Limited lens, a modest zoom of minimal proportions, sized for the sweet spot between wide and tele. A "prime zoom," as some have said, or a "stack o' primes." The F 24-50/4 seems like the perfect candidate for that.

[jatrax]

If you look through those charts you can see results from a range of older zoom and prime lenses. The F 24-50 gets good results, surprisingly the F 35-70 did not fair as well as I expected but in general the F series zooms performed better than the few FA series ones I own. Even the 'kit' F 28-80 turned in a nice result.

However these test images are only with my copy of the lens so another copy might produce a different result, especially given their age.

I was satisfied with the F 24-50, F 70-210, FA 20-35 and FA 100-300 for use on a regular basis. But since I also have newer lenses such as the DFA 24-70 and DA*60-250 these get most of the use. But you could make a very nice light weight K-1 kit with the FA 20-35, F 24-50 and F 70-210. Add a F 35-135 if you like that range. I would not hesitate to use any of these for paid work.