Right! Finally the shims arrived today and I've fitted it and got it working correctly. It was actually really not too hard to fit. I got a bit daunted by the fact that the shim is not classed as a "user serviceable part" but it was all fine.

For me the 0.25mm shim was the right one. Apparently most k-30s come with a 0.35mm shim by default so the .25 was 2 steps down.

For anyone that needs to buy these you can get them from here:

www.johnsons-photopia.co.uk

The part numbers are:

77240.M02200A - 0.10mm
77240.M02200B - 0.15mm
77240.M02200C - 0.20mm
77240.M02200D - 0.25mm
77240.M02200E - 0.30mm
77240.M02200F - 0.35mm
77240.M02200G - 0.40mm
77240.M02200H - 0.45mm
77240.M02200I - 0.50mm

Pentax refer to them as 'washers' rather than 'shims'.

They cost me £6/shim inc p&p. I had to buy 5 in the end because I wasn't sure which one I needed.

One thing I wanted to say is that I can't say good enough things about KatzEye Optics and particularly about Rachael Katz who was incredibly helpful throughout the whole process. The focus screen was dispatched quickly and packaged well, she responded to emails really quickly and spent a lot of time advising me on how best to check the calibration of the focus screen and even assessing the photos my camera was taking to check that my calibration was correct. I'm really impressed and wouldn't hesitate to recommend them to anyone.

Thanks also to all on here who helped me out with advice.

Now very happy with my focusing - time to get out and take some pics!

Ok so results:

I tested using live view and also using the calibration testing procedure that Rachael Katz from KatzEye suggested I use (taking photos of a printed scale at fixed distance and reviewing the output).

The camera is front-focusing slightly so I think I will need to fit a thinner shim.

I think I'll start by getting some quotes from shops that might be able to do it. If it's cheap enough then I'd rather pay and get it done professionally than try myself.

Thanks! I've bought ProCapture to have a play with. Not too cheap (for an app) but it seems good so far.

This looks really good. But I don't think it lets you take photos. Just process them afterwards... as far as I could tell.

Thanks for the reply but sorry, I wasn't really clear. I meant the camera app (i.e. for taking photos on the phone) not for processing them.

Don't think you can shoot RAW on a phone sadly.

Hello,

Wondering if any of you guys have recommendations for alternative apps for Android photography?

I've got a galaxy s3 and although the photos are fine I suspect they could be better.

I'm really wondering if any apps can produce better image quality. I assume they each have different algorithms for jpeg processing...?

I don't really care about filters or effects. But it would be good to have as many manual settings as possible.

Most of the reviews online look to be aimed at which apps give you the most different filters, adding on vignetting etc. I just want the best possible image quality.

Any tips would be great.

Ok thanks!

I don't know why I didn't think of using live view. I'll give it a go.

I'm really hoping I don't have to start adjusting the calibration. I was nervous enough just getting the screen in!

Well! My Katzeye focus screen has arrived safely and I've fitted it in.

I'm concerned about the calibration though. It is really fiddly to tell if it is all right. On a Pentax AL SMC DA 35mm f/2.4 the autofocus doesn't seem to give the same result as the focus screen. The split screen is still slightly split when auto-focusing on vertical lines (e.g. corner of a door). Or is that as expected because the focus screen is more accurate than autofocus?

Jonathan-Mac - If you don't mind me asking, any tips would be great. What did you do your focus test shots on? Where did you buy the shims to do the adjustment?

I'll have a go with those tonight. Thanks!

I think I actually have a couple of panoramas that I never got round to stitching together.

And then you could have an EVEN bigger sensor...

And you end up with this:

Thanks for the tip.

I don't have either at the moment so I'll probably try to find a free / open source solution initially.