Two more front ends

with regards the WR/dust ingress situation why can't they be labeled with an IP rating , at least we could all check the level of protection to a given scale.

That would mean testing and certification at an accredited independent testing facility. An expensive exercise indeed. You could approach such an establishment and get a quote for testing but be warned, they will test to failure to determine the highest protection levels.

Best regards

I have a DA* 50-135 and a Sigma 135-400. While the IQ of the 50-135 is slightly classier I've never once felt the 135-400 was lacking becuase of it's IQ. It only cost around £300 as well. You can bet a DA* 135-380 would be well over a grand

Fair point but I have a bit of a fixation on dust and weather sealing which rules the Sigma out for me

If they did bring out a DA* 135-380 I would definitely consider swapping the 60-250 especially if it was constant f2.8. I can dream can't i

I've used my 135-400 in duty and moderately rainy environments without problems. As Gary Cabstar says all the Pros bung on a plastic cover anyway. I wouldn't use anything in a sandstorm or storm without external cvoering


A DA* 135-380 constant 2.8 would probably cost about £10,000

My next trip is into the hinterland of Iceland for 2 weeks including, dusty roads, waterfalls, geysers, volcanic ash and a whale watching trip on a boat. In 2015 I'm hoping to drive the Southern Algeria to the centre(ish) of the Sahara desert.

Although a cover would be beneficial at times I need an ongoing degree of dust resistance even when stored in the vehicle (Land Rovers aren't renowned for their dust resistance:blush.

Thanks for the info though


As I said............I can dream

The answer is that build quality is variable. I have rejected three examples that had unacceptably wobbly barrels and sloppy focus rings (and plenty more examples of this have been reported elsewhere and even demonstrated online) but no doubt others will report that their 17-70s have tight barrels and perfectly damped rings. IMHO Pentax lens QC still has room for improvement - but that's a different thread.

Best regards

Jim

Thanks Jim. I confess my 17-70 zoom creeps as I carry it which is a source of annoyance.
Regards,
Ian.

The build quality of my 17-70 is excellent, as is the image quality, no complaints at all regarding this. I would also say the build and IQ of all the Sigma lenses I own is also excellent, although I'm not a fan of the finish that Sigma employ as it's too prone to marking and scuffing.

I think Pentax are well capable of releasing a DA lens with excellent IQ, they have proved this with the 17-70 and the 18-135, both of which seem to suit most of their owners in IQ terms. I too suspect the lens will not be FF capable, not a big issue for me. My suspicion is that if and when Pentax go FF, it will not be with a DSLR. BTW, I base that not on any known facts, just a gut feeling.

Regards
David