The DNG format allows for JPG thumbnails to be embedded for quick display. Pulling apart a DNG off a K20D it contained both 4672x3104 JPG and a 640x480 JPG. The first of these adds substantially to the size. The PEF, on the other hand, contains a 640x480 JPG and a 160x120 one. When you use something like Photoshop to convert the PEF to a DNG it only carries these smaller thumbnails across and doesn't create a new humoungous one, hence the smaller size. I've not investigated a DNG from the K-5 yet, but I'm guessing it no longer contains the full size JPG.

Paul

I used PEF till I upgraded to the K-5. It seems the K-5 uses a slightly different version of PEF that my aging copy of Photoshop doesn't recognise so I've had to move over to DNG. I've found no difference* in doing so.

Cheers,
Paul

[*Erm...that's no difference from my old workflow rather than no difference from something that doesn't work.]

Strictly speaking, they need at least some level of release to back up their servers, migrate them to new hardware etc. It may be that they're trying to cover their backs for ill-defined stuff they might possibly do in future rather than have to issue new T&Cs each time.

I wonder whether you could use this for focus stacking...?

I think that's what I was trying to say, but you've done it more succinctly.

Cheers,
Paul

You raise a couple of points here, PentaxExpert.

Firstly, there's the question of artistic expression not always being technically perfect. While there's an element of truth in that, the 'rules' (which are, admittedly, just guidelines - cue piratey voice) have evolved because people have found them to work well. For example, think of five poets who write metric verse. Now think of five who write blank verse. Which was easier? Alternatively, think of five tonal composers. Now think of five atonal ones. Again, which was more straightforward? Generally speaking, the even the ones you remember are those who have proven themselves in a structured environment first - this allows them to plausibly say "I'm not sticking to the rules because they're daft" rather than "I'm not sticking to the rules because of my lack of proficiency".

The basic rules of composition aren't onerous - here's a good summary to which I'd add an extra one of checking your histogram to make sure you've not blown anything out. A couple of years ago I had the startling realization that although it is possible to take a striking image while completely ignoring them, bearing them in mind ups your hit rate considerably.

As to your comment about not seeing beyond the end of a DA* lens, I'm aware that I'm no longer in a strong position* to comment on that, but in my previous reply I did mention some staggeringly good photos taken on a cheap plastic cameraphone lens. The manufacturer's price point for those is normally less than a quid.

Paul


[* Though that's only a recent change. Most of my learning experience was with a K100D and a Sigma 18-200. I'm not sure the upgrade of kit has made my photos substantially better, though I'd be lying if I didn't say it's made the process a whole load more fun.]

I've had really good results from the Sigma 18-200, though I'm aware most people don't rate it highly. Perhaps I have a particularly good copy but I found that it was pixel-sharp on a K20D.

Example at wide end: http://www.flickr.com/photos/pm107/2360608311/ (not sure why the EXIF reports two such different focal lengths!)

Example at long end: http://www.flickr.com/photos/pm107/3494447578/

Cheers,
Paul

I like #5, particularly the contrast of the finger with a blingy ring holding a copy of Socialist Worker...

A while back there was a series on BBC4 where three photographers were given wildly different cameras (usually a digital medium format, a top-of-range compact and a mobile phone) and given a project. All the photos were shown at the end of the programme and the mobile phone guy turned in far better photos than I could take with my DSLR.

OK - this may tell you that I'm a rubbish photographer (but improving ) but it also shows that someone with a good eye can still take really good images even with a pre-smartphone mobile camera.

Sent PM re the 15mm.

Paul