Blimey Pete, just how much did you sell your car for?!?

If I ever need to sell mine, I'll pass it on to you and let you have 10%, I reckon I'll still be quids in with a bit to spare for a new lens or two.


The 16-45 is better than the kit lens that I got with my istD (18-35), but crucially for me it had that extra bit of wide-angleness to it, every millimetre counts at the wider end. You'll have to decide yourself if you need that wider angle, and the slightly wider (and constant) aperture.

If I didn't already have the 16-45, and had some cash wearing a whole in my pocket, I'd definitely go for the 16-50 2.8.

Dan

Hi Ken,

I don't know why you'd get the red cast on some images, although I would take a guess that possibly the colour of the flash would vary slightly depending on how much charge the heads held when fired...? Might be that a few shots in fairly quick succession doesn't allow the heads to gain full charge, and perhaps flash with a slightly warmer tone.

I did a shoot a few weeks back, with a white background and small aperture, using flash. Perhaps I should have posted about it, because I had the same problem as you - dirt on the sensor that was invisible at 'normal' apertures. I cloned/magic brushed them out, but as it was a small shoot, it would probably have been just as quick to re-shoot, if I hadn't already disassembled my 'studio'.

Note to self: Clean sensor before shooting with flash and white background.

Regarding the file sizes, I'm guessing you saved the jpegs at 'Maximum Quality'. Try doing a couple at 'High Quality', and see if you can tell the difference. If not, then use that setting and you'll probably get file sizes of 1-2Mb.

Dan

Which is why I started with "Now I'm not saying that pixel numbers equals resolution..."

Just did a bit more maths, and came up with approx 4.25Mp as a maximum for compact sized sensors, judging by Mr. Mead's figures. Perhaps he's got a point.

I'm guessing that there are a few limitations at the moment regarding pixel count in DSLRs.

First would be noise - the compact's sensors are undoubtedly noisier than APS or 'full frame' sensors. So an advantage of a lower pixel density is lower noise.

Cost would escalate quite rapidly I would think, once bigger chips are being made with higher pixel densities.

Processing power must be a limitation at the moment - if you were getting images 4 times the size, it stands to reason that the processor would take 4 times as long to process the file, and 4 times longer to write it to the card.


Not sure I understand the question... My istD has a 6Mp sensor, but each quarter of that is 1.5Mp. It's what tends to happen when you divide something by 4. You'd probably have a bit of a job to get a seemless join between 4 sensors though...

Dan

Now I'm not saying that pixel numbers equals resolution, but just so you know, the current 10Mp compacts, with sensors approx. 7.2mmx5.3mm, have a pixel density of around 260,000/mm2.

That is 162,500,000 pixels per square inch.

I think there's still a long way to go before the APS-sized sensor is maxed-out.

Dan

You've got too much time on your hands...

Dan

As an extra consideration, just had a quick look at the Sigma, and noticed that the barrel distortion is all but gone by the time you've zoomed from 10mm to 12mm.

If this was a focal length that you needed a lot, then it this lens might give you better results from a drawing point of view than the Pentax, although that's purely based on the assumption that the Pentax will suffer from distortion at 12mm.

I am fully prepared to stand corrected!

Dan

Hi Snappy,

I've got the Sigma 10-20, and find it a nice lens - certainly very well made and solid, like the other EX lenses. No play in the lens barrel at all, and feels lovely. Focusing is quick and smooth.

Having said that, I don't use it nearly as much as my Pentax 16-45, which I got to replace the kit lens (18-35) that I got with my istD. I was used to the angle of view I got with a 24mm lens on film, which is the same as 16mm on digital.

I got the 10-20 because there were situations when I needed a wider view, but couldn't justify the cost of the Pentax 12-24, and I felt that that lens overlapped a little too much with my 16-45 too. On the occasions that I've used it, I've been more than happy with the Sigma.

There is barrel distortion at the wide end, and it is noticable on horizons (see below), but I would assume software would correct this (PTLens?), not something I've investigated.

Image below taken handheld, at 10mm, 1/1000s at f/9.5, into the sun, using the supplied petal lens hood. Enlarged areas are shown 'full size', ie the same as if you were looking at them at 100% in photoshop. RAW file converted in C1 LE (no sharpening), USM of 120%, Radius 1, Threshold 0 applied in PS.




Form the bottom left hand corner:



From middle right:




As far as drawing any conclusions from this - you can't really, other than decide whether the level of detail is sufficient for your needs, distortion is excessive etc. You can't compare it to any other pics you might see on the web as the conditions would be totally different, but as an isolated example here it is!

Hope that helps,
Dan

Worth noting that SRSMicrosystems are doing the K10D + Grip for £648 at the moment, so the grip's £99, when bought with the body (currently £549). Proper UK stock with full UK warranties.

Must get round to getting one.

Dan

Oh well, just hoping you might have made the sort of mistake I would have done!

Dan

They are fantastic. I'm not usually one for portraits, but I really like the lighting and style of these, and the rest of your work.

Think my favourites are 'hindouisme' (where do you find a model with 6 arms? ) and 'taoisme', just love the patterns made by the lights on the backdrop.

Having said that, 'orthodoxcloseup' has a real immediacy to it - feels like you've just run up close to the model and looked her in the eye.

Now, seeing as you're sponsored by Pentax, and you get to play with new toys before the rest of us , and although I feel a bit embarrassed to say it when faced with images of this quality, I feel obliged to ask:

The very top left corner of 'taoisme' - is that the edge of the backdrop?


I get very picky when faced with great pictures - it's when the competitive streak comes out in me. Just wish I could do this sort of image, at anywhere near the quality, design and style of yours.

Dan