The design team at Pentax must have been getting really fed up with all those discussions! Maybe they've been logging on here I don't want to contradict people who have experienced no issues, everyone's view on it is valid. I feel some thought and caution is advisable, as it would be a shame to have an image affected by moire when it was not possible to reshoot.

But, yes, the K3 is a neat solution, to a problem that may or may not exist.

As I said, not everyone shares my views ! Steve, I take it then that you would regard the revolutionary new 'aa filter simulator', bought to us for the very first time by Ricoh & Pentax, as a waste of money?

I have never seen a clear explanation of exactly what camera fine tuning settings are actually interpreted and acted on by a 'third party' editor like LR. Even assuming (as I am) that your custom image settings on both cameras are identical that doesn't mean that the 'zero points' for each preset are not different on each model. There is a 'hue' adjustment slider within the custom image menu though, so its worth checking thats not different, and of course also the main WB fine tuner as well.

But, clearly, the K5 DNG shows less obvious and finer colour noise than the K3 one. This test at 1600 is contradicted by David Storms one, where he concluded that the K3 was better up to 3200, if I remember rightly?

My own view on all this, as someone who enjoys messing around with different noise reduction software, is that its not so much the starting point with noise thats important - its where you end up after processing that matters more, and the critical part of this is the detail recovery capacity of the file following noise reduction blurring. The additional pixel data with the K3 may well prove beneficial here.

Its an interesting comparison, thanks. Unfortunately I think the colour balance discrepency messes things up a bit - the magenta cast on the K5 image somewhat disguises the (mainly) yellow colour noise, so it is a bit difficult to assess confidently.

Can you reshoot the K5 image and try and match up the colour balance? I think then we could see a more valid comparison.

But, it does appear, even with the colour cast issue, that the K5 DNG has less colour noise 'out the box'.

I did say K7

I can refer you to my own research into this, which will provide a good read .... link (PentaxForums Articles).

To greatly summarise the conclusions, I saw it as coming down to two factors - the methods you use for image sharpening or detailing, and the size of output limited to the point that any sharpening or detailing will become 'degrading'.

So, I concluded that for camera JPEGs, the default sharpening effectively equalised the images. For RAW, the K5IIs had the advantage if your sharpening methods were globally applied, and you didn't isolate smoother textures to avoid artifacts as the detailing was 'cranked up'. Of course, the extent that this was significant would depend on how closely you look at the images, or how big you printed them.

If you did carry out more sophisticated, selective sharpening methods, including differing radius settings and / or micro-contrast - type approaches on targeted areas, then I did not find such an advantage to the 's' model.

There's no doubt that both K5II models should represent increasingly great value for money as the K3 beds in. For your listed photography subjects, I do feel that a risk exists of encountering moire defects, in unexpected places. But this view is not held by some others. I feel its early days yet to discover exactly how much of a problem moire will be in an aa filterless cameras, so for myself I would play safe and go for the K5II.

But in my article there is a conclusion for every situation!

Now that will be something to watch out for, definately - if I throw some bread down I might get one hopping around a bit and carry out a thorough test of the K7's AF tracking abilities!

We'll have to agree to disagree on this particular Penguin, the poor thing It seems that we are still to find a common consensus on how to define moire exactly, and how it differs from colour noise, or indeed colour iridescence.

As I said before, I'm not wanting to overplay the effect here, its not going to ruin the image except when viewed closely, but I would not want it. I see it as exactly the sort of thing that an aa filter simulator is intended to deal with. I find it difficult to accept that in real life this birds head has those colours on it.

Its the unpredictable nature of moire that is the concern - so efforts to 'induce' it may be futile, as it may well strike where we won't be looking In any case, having a few common guidelines on using the aa filter simulator would surely be a good thing. (And before anyone says it, no, I don't think we can rely on shooting without it first, then checking the LCD screen to spot problems - thats not practical in real shooting situations).

I'm sure this is right in many cases of bird feathers, but I can't believe that is the explanation for this particular case - this penguin is black, and there's nothing on its head that would produce any 'iridescence'.

I'm not trying to overplay any moire here - no doubt it could be reduced in processing (as the OP said), and at average viewing sizes may not be noticed. I'm trying to highlight and help identify where the risk exists so that there can be some method to ensuring that the aa filter simulator is activated when needed - its too late once you're checking the image on a computer screen.

Yes, the effect is a bit nausiating The eye doesn't really latch onto the leaf at all, but rather wanders uncomfortably around trying to find something else to latch onto !

A good idea to try out though.