Now moved to the correct section and the duplicated thread deleted.

Welcome to Pentax User by the way!

Don't forget the sister site to this one

www.photodo.com

which has tests and reviews of lots of older lenses from all manufacturers.

It will only make a difference if you want to use the lens very close or on bellows/extension tubes, etc. The f1.7 has a flatter field.

If you want to take low light hand geld shots then the choice is clearly the f1.4

If one of them was bought new and the other wasn't, then I'd opt for the one that was new.

Otherwise, they will both do a very fine job and i don't think you would be able to tell which design was the sharpest.

Go to Image>Image Size and enter the dimentions you want. Also enter 300ppi as the resolution. PS7 will resize your image accordingly.

The default method of resizing will be Bicubic, which is where it should stay.

Now this assumes that the proportions of your image are 16:12. If not, you can set the 16" and the other dimension will adjust automatically. For example, it could end up 16" x 11.78" if that is the shape of the picture.

If that is a problem, resize using the crop tool instead. Enter 16in and 12in and 300ppi and when you pull out the crop box the proportions will be right. This way you will have to lose a bit of the image somewhere, but that should not be a major issue. Don't forget to click the Clear box when you have finished with this dimension and want to do a different crop on something subsequently.

I am currently offering a SMC Pentax-A 50mm f1.7 on eBay....

That is so tempting, but I cannot tell a lie....

It wasn't the APO version, just the ordinary DG lens.

We like the SMC Pentax-FAJ 75-300mm because it's compact, has no silly macro switches and performs very well for its price.

It is sharp, not bitingly sharp, but the appearance of the images is very pleasing.

What needs to be watched is the fact it's a very long lens, so camera shake and atmospheric haze can easily take the edge of the image. This would equally well apply to any lens of this focal length.

In her continuing quest for a better 70-300mm lens, Sue brought home a Sigma 70-300mm f4-5.6 DG Macro today, which we set about comparing to our Pentax FAJ lens.

Again a messy switch arrangement for Macro, which I don't like, but this lens seems to be better than the Tamron tested previously.

The Sigma and the Pentax performed in an almost identical manner at a variety of distances and apertures. Absolutely nothing in it.

Thanks, Nathan, that's sensible advice.

Pricing is always a tricky thing and for most people the price they pay will depend on how knowledgable they are, or just plain luck as to where they normally shop.

Currently the original 18-55mm is available from SRS at £29, post free for forum members, which is incredible. It's also brand new from a dealer with full warranty. Forum members will be aware of this and unlikely to shop elsewhere for this item.

In this context anything over £29 is too expensive here, but on eBay it will depend on where the buyers are and what other prices they have access to. Some dealers are still charging £40, £50 or in some cases over £100. I think I'm right in thinking there was a recommended price of £199 at some time. The highest prices dealers can be non-photo sources, although I recently bought a 43mm Limited from Amazon for just £254.

The 50-200mm has also been available at some very low prices, especially the Samsung version.

These extraordinary prices make it much more difficult for us mere mortals to sell our excess items on eBay, but I guess that's life.