Yes, it's better to upsize in the conversion software (especially with Capture One Pro). Interpolation is better at that stage.

That said, the upsizing in PS-CS/CS2 is very good indeed (bicubic smoother usually). Depending on the image, it may be very hard to tell the difference between RAW upsampling and PS upsampling.

With careful sharpening you can still get some seriously sharp images out of the *ist-D. I stagger to think what the Hasselblad can do with 39Mpixels! (Except completely stuff up your storage )

Perhaps I should qualify my statements above: if you are printing to photographic output, then upsample to the exact output dpi. If you are printing on an inkjet, then this is a judgement call - 250dpi properly sharpened may be great. Personally, I haven't seen anything sharper than ProAM Imaging's output at 402 dpi (for which you need to upsample to the exact size). Most definitely sharper than 300dpi from Photobox

Matt

Ordinarily you should optimise the DPI according to the output device.

If the output is 402dpi, then you're best off upsampling to A3 at 402dpi (ie 6647 x 4700 pixels). You also have the opportunity to apply some sharpening at the output resolution which will increase the perceived resolution.

I recently upsized some *ist-D images from RAW to 16"x20" at 402dpi, sharpened in PS-CS2, and the results were great!

So, in answer to your question - forget how much you are resizing by, just resize it to match the output device (because a mismatch will likely be worse, and you have no control over what happens).

Hope that helps,
Matt

Kimbo,
Erm, personally I wouldn't try one of those. The electronics inside the camera don't like high voltage discharges up 'em
In the electronics industry you go to huge lengths to avoid high voltage static discharges!
Matt

Don,
Indeed you are right. What I meant to say was that cleaning upside down when you've already got dust on the CCD probably won't help much.
Best thing is never to change the lens (though that may not completely prevent dust). Next is to change in a dust-free environment (preferably a clean-room!).
And, as has been said before, it is more successful if you clean the CCD on a tripod (pointing somewhat downwards), in a room that's free of dust (the bathroom after a hot shower being a good choice).

I did read once that someone suggested cleaning the CCD without clothes on, in the bathroom... might be safe as long as no one finds out

Matt

Gravity doesn't necessarily help
CCD are, by definition, charged (Charge Coupled Device) and hence dust tends to stick by static.

Initially the dust is hard to notice, especially if you take images of highly detailed object. The best way to check a CCD for dust is this:
* Put camera in MF mode
* Set aperture to f22 or smaller
* Manually focus to the nearest point
* Point at the sky

(You really just want an even light source and a very small aperture.)

Any dust spots now show up as dull grey splodges. And you might be surprised how many there are

Matt

If I can't blow it off with a "Rocket Blower" (never, ever blow with your mouth!!), then I have to clean properly.

That involves using Eclipse fluid and PecPads on the end of a piece of flat plastic. One drop of Eclipse, wipe across the CCD and that's clean (may need to do it twice).

The coating on the CCD isn't that delicate actually Treat it like an expensive filter and you'll be fine.
The biggest problem is getting access - it's a long way in and it's fiddly. Absolutely make sure you have good batteries, because if the power fails while cleaning the shutter will close... crunch!

As has been said, there are various kits available that make it a bit easier.

Matt

Wow! Great deal

Steve, if you need someone to relieve you of an FA50mm/1.4, then drop me a private message

Matt

Would I trade my Pentax 16-45 for something else?
No.

Resolution is astonishing, flare control unbeatable. An extremely useful and usable lens. Especially good for landscapes with some ND grad filters. I think all of my half decent landscapes were shot with this lens. (Just remember the "Riley Rule"!)

Not that I've got anything wrong with the Sigma EX range. They're well made lenses, and you can get excellent results. However, from what I've read, if you get one, check it out thoroughly first and return it if you're not happy (there seems to be a great variation in quality, even in the EXs).

Compatibility is the other issue. Sigmas often don't work correctly on newer (or older) camera bodies. Since they reportedly reverse engineer the body-to-lens protocol (rather than paying royalties) you can get issues regarding back-focusing and the like (i.e. focus on the wrong point).

Best to get a trial period
(Or a Pentax )

Matt

Agggh! Don't tell me that