What's the easiest way to check for front/back focus ?

Jason

Just done a quick sharpness check (very non scientific brick wall). This lens is very sharp wide open most of the range, but at the longer end (50mm-70mm) needs stopping down a bit to get best sharpness, especially in the corners.

Can't say I'm at all disappointed in this lens though, but will be giving it a thorough workout.

Also Bokeh seems to me to be very impressive.

Anyone with this lens confirm this is normal for it ?

Jason

I have just arrived home having travelled up to Watford to buy a Pentax 17-70mm lens. (2 Hours there/ 1 Hour return, bloody M25 !)

I have mounted it on the camera and just tried a few test shots, I like the colours and silent motor too (it was that quiet I had to double check it was working).
It also just seems to be the right size/fit to compliment the K20D with grip, not too small or too overpowering.

I will be doing some sharpness tests with it shortly to see if it is as good as I hope.

Jason

ps. Was told at SRS that prices are going up pretty soon so if you want a good bargain get in quick.

£60 + P & P ono.

Jason

I'm hoping the SDM will make up for the price difference.

I haven't used any of the lenses you have mentioned above but am in the same situation.

I think I have finally decided on the Pentax 17-70mm. My only concern is the sample variation that I have been reading about with this lens. Hopefully I will get a good 'un when I finally order it.

As long as it is reasonably sharp at f/4.0 I will be a happy bunny.

Jason

Hi

I am putting a Jessops 360AFD Flashgun (Pentax fit) up for sale. I only bought this new 2 weeks ago and have only taken it out of the box to try out once. It is in it's orignal box with paperwork.

I am selling this to fund a new lens.

I am open to offers but would be looking in the region of £60 + P & P.

Jason

I have decided to drop the price to £50 delivered (UK).

I'll give it until the weekend and then off to ebay.

Thanks

Jason

Thanks for the responses, that's just what I was looking for.

Is it sharp from f/4.0 or do you find it needs stopping down a bit ? as I understand it the 16-45mm is pretty sharp wide open.

Jason

Hi.

I have read as much info as I can about these two lenses but would like some advice from owners of the 17-70mm (I know there are a few on here).

The 16-45mm seems to be a stunning lens with not much sample variation, ie. most copies seem to be excellent.

While the 17-70mm lens seems to have some sample variation, maybe not as much as the 16-50mm but more than the 16-45mm.

If the 17-70mm is as good as the 16-45mm lens but with the additional length and SDM I would go for this lens.

So my question is:

Is the 17-70mm as good as or better than the 16-45mm ?

I know this could be sample dependant.

Thanks

Jason