indeed not, it's a chinon. I had the F1.9 version at one point, not a bad lens but not as good as the Pentax equivalent. I replaced my Chinon 1.9 with a Pentax F2 and was happy. Later I got a Pentax A series 50 F1.7 and was happier still.

as far as I'm concerned, the default position for SR should be "on", only turning it off when on a tripod.

HERESY!!!!! BURN the HERETIC!!!!!!

PEFs will preview at full size in both directions, that is the K10 can read *ist ones and more surprisingly my *istDL2 can preview K10 PEFs.

You can only preview at full size though, not zoom in. Presumably this is because the full size preview comes from the embedded JPEG while the zoomed in version is created from the PEF itself.

I would love the second and last of those above if the eyes were in focus. When you're playing with the 50 1.4 your DOF is razor thin and it's very possible to have part of the face in focus and part out. The eyes are the most important bit, if the eyes are good almost everything else is forgiveable, without the eyes the photo will always lack punch.

the Kiron 105 is a cult classic macro lens. It is regarded by some to be the best ~100mm macro ever made by any company. I have one which has a fault with it's focusing but it is optically stunning, when I can scrape the cash together I plan to have it repaired.

If it goes for less than £100, snap it up.

I reckon it goes

18-55
FA 50
Sigma
DA*

how close am I?

Just in case you have missunderstood Matt, I think it should allow speeds above 1/180th with the ISO forced to anything, not just 1600.

Basically, the camera doesn't like doing flash above 1/180th because even with HSS it still looses guide number by doing this. Thus, if you give the camera any degrees of freedom at all it will try to keep the shutter speed bellow 1/180th of a second. For example

you set Av, F8 and Auto ISO. The camera determines 1/180th and ISO 200 for this shot. You then change to F5.6, the camera has two options. It can push the shutter to 1/360 or drop the ISO to 100. The former requires the camera to engage HSS and loose half its flash power, so it will judge the latter a better option and drop the ISO rather than increasing shutter speed.

The K10D has such easy ISO adjustment that I keep it on manual all the time. I have Av, Tv and Sv set to use the front dial for ISO. I find this way I am much less likely to get home and realise it took that great sunset on ISO 1600 (or at least if I do it's my fault!)

not really relevant, but just FYI

with Sigma lenses DG means full frame coverage with digital optimised coatings, DC means reduced (1.5x) frame coverage.

DC/DG makes no difference to the focal length and crop factor, it just means that DC lenses can't be used on full frame

as yourself this question:

Why do I need to upgrade?

what is wrong with your current system as far as you are concerned?

what shots are you yerning to get which the K100D + 18-55 can't give you?

If you can't answer this question then I would suggest that you do not need to upgrade anything. If you can, then the answer will probably lead to which component is holding you back.

feel free to post the answer here and we will help you as to what you can do about it.