Honest thoughts on the 28-105?

I'm reading a lot online about the new 28-105 and how good it is.
I've been having a few troubles with the 24-70 even using AF adjust its just not as sharp as I'd expect given the price and I'm weighing up the alternative.
I don't "need" f2.8 as I tend to be shooting landscapes and I'm sure the 28-105 would be fine for that, I would miss the 24mm end but its possible I could invest in a 15-30 if I haven't splurged as much on a 24-70!

Just wondering if anyone here has compared/tried both and how they found them?

https://www.ephotozine.com/article/hd-pentax-d-fa-28-105mm-f-3-5-5-6-ed-dc-wr-le...

https://www.ephotozine.com/article/pentax-hd-pentax-d-fa-24-70mm-f-2-8-ed-sdm-wr...

Both were excellent lenses, but I bought the 28-105mm. There were three reasons for the choice - cost, bulk and the slightly longer reach of the 28-105mm. Although the 24-70mm might be slightly better in some ways, in practice it doesn't make much difference.

Can you return it or get it checked under warranty? At the price they are it should be more than fantastic. Mind, basically the 24-70 is a rebadged Tamron whereas I understand the 28-105 is a new Ricoh/Pentax design. The 28-105 wins hands down on weight, bulk and cost (it's similar to the DA 18-135) so it depends how important the f2.8 and 24mm of the 24-70 is. Performance of the 28-105 is pretty good as is the 15-30 you mention. They do make a good pairing with a 70-200 such as that Tamron. I'd expect the Tamron to be back to around £499 after Christmas as it was for the Black Friday at SRS. It's a good, albeit heavy option.

I think twice before setting off with some of my lenses because of their weight and size, but the 28-105 I pick up without a second thought. Given its widest aperture setting, It would not be my go to lens for portraits, and for close-ups and low light photography it has limitations, however for all other purposes it serves well for a wide to short telephoto zoom. It is parked on the K-1 and never fails to delight. It may be similar to the 18-135 in style and handling, but it is far superior in terms of resolving capability and overall performance. John's ephotozine review gives a good and accurate account of it.

In short, an excellent lens given its relatively low cost: the results (especially if taken in good light) certainly do not look like kit lens photographs.

The 15-30mm I find to be an excellent clear and sharp lens, and use the 28-105mm as a great general purpose lens which is easy to carry around. The two together with a prime or macro lens in the bag are manageable and cover most situations. I have toyed with getting the 24-70mm and 70-200mm but am put off by the weight; they would force a choice as to what I would take and leave behind which is a bit pointless. Instead I am looking to a couple of primes to supplement the 28-105mm where I need more reach or wider aperture.

Thanks everyone for the feedback, I just feel that given the price for the 24-70 (although only about £860 as it was a K1 bundle), its still not really there, I don't mind the size and weight too much but it just doesn't seem sharp enough, an issue I ran into with a copy or two of the Tamron equivalent for Nikon.

I've asked SRS if I could return the 24-70 and exchange it for the 28-105, I think I'll be happier with the cheaper lens (I won't expect so much from it) and the loss of a fixed f2.8 isn't a biggie for me as I like shooting primes too so I'm adding a few key ones to my kit.

I will look at the 15-30, I tried the Tamron version on a D810 last year and was blown away (theres a reason people buy it over the fabled Nikon 14-24!)

I wasn't overly impressed with my 24-70, but now I have fine tuned the AF it is very good. I have only tried it out indoors at iso 3200, 1/250 sec, f2.8 at 50 to 70mm, but I think it should be good at other ranges. I had to give it +7 adjustment.

The 15-30 is a cracker but the filter holder plus filters will be expensive.

Yep I think I may have managed to sort it via the AF adjustment but will need to give it a proper try, I'd rather keep the 24mm end of this lens as I can't see myself investing close to £2000 for the 15-30 and filter kit, looking for a 20mm though!

Just need to decide on a prime or two now, the 50 FA 1.4 is a cracker and half tempted just to pickup the fairly cheap 35 FA 2 but I had a chance to try a 31mm Ltd and that thing is just magic, Sigma 35mm has always been a good performer too on full frame but seems to get mixed reviews from Pentaxians