I must say that this new model (the *ist DS) is a cracker, and easily the leader in the low-priced SLR group. As a result, the *ist D does look expensive by comparison. Although the D would still be the camera of choice for serious photographers, the quality of the DS, and the much lower price, would be very tempting.

I suspect the D will get an upgrade fairly soon.

Pentax have recently announced some new macro lenses for digital. Might be worth waiting.

Look here for advice on Pentax brand lenses:

http://stans-photography.info/

The SMCP-F 70-210 f4-5.6 is generally considered pretty good for a slowish zoom. The fast ones cost much more, and if price is a factor, they should be ignored.

If you can do without autofocus and shutter-priority, the SMCP-M 70-150 f4 is very good and very common. They go for around £30-£40.

George

Prices for 50mm lenses on Ebay are very low. I recently picked up an excellent SMCP-A 50mm f1.7 for £15.00. M lenses can go for as little as £12.00. However for the MZ-M, the A lenses will give the most functionality.

Where are you based? I have a perfect one for sale, in the UK.

The SF7 was called the SF10 in the USA. It is well-made by modern standards

£70 is not especially cheap for this camera/lens combination. You might be able to do slightly better on Ebay, though if you can see and handle the camera before buying it, that is worth something.

George

Thanks, John.

Don't go to any trouble. I was hoping you might be able just to point me to something. I've been looking, but can't see anything that gives a clear side by side example.

John

Do you have any side by side examples you can point to on a web site?

Same position, same subject, same aperture, same field of view, different focal lengths and different frame sizes so as to give the same AOV?

There's just too much optical theory to absorb for an old brain, and much of what is written doesn't address the question of what happens when you use different frame sizes with the same AOV.

Do you know of any sites that demonstrate this phenomenon with pictures?

I am not wholly convinced by the DOF argument, and would be interested to see two pictures side by side of the same subject shot from the same position at the same aperture with lenses that have an equivalent field of view on the two cameras (35mm and APS-size). A 77mm and a 50mm would probably be near enough.

One reason why the apparent depth of field on a long lens is shallow is because in fact it is covering a much greater distance. Put a smaller focal length lens on a camera with a smaller frame size, and I don't see why you won't get the same depth of field.

George

The smaller "format" of digital will mean a narrower angle of view. I don't see how it can affect the depth of field.