There are two parts to HDR photography:
1) Image capture & combination
2) Tone mapping

The quality of the first part varies greatly. The idea is that you take 3 to 9 shots, 2Ev apart and combine them. Some software is terrible at handling any differences between the frames (like people moving etc), some is much better. Adobe's HDR in CS2 is pretty terrible, and I use Artizen (though Photomatix is purported to be very good at handling ghosting too).

The second part is where the "distinctive look" comes from. Photomatix has only one tone mapping operator, whereas Artizen has a complete set. I find it helpful to have multiple tone mapping operators available because they handle different situations, and can produce different looks.

In fact, you can tone-map a single image to produce that "HDR look"... if you want to, of course

I did try quite a few HDR packages, and in the end plumped for Artizen. The user interface is not the slickest, but it is actually very capable. Be warned - you will need a bucket load of RAM and plenty of time to handle true HDR

When doing this I will use Silkypix to process the RAW files. Work like this: pick the shot with the most detail, and set up the parameters so it looks ok. Do NOT adjust the exposure compensation!!! Once you have the white balance, sharpness, contrast, colour etc all to your taste - copy the parameters and paste onto all the other RAW shots. Now process them all to 16-bit TIFF files. Bring the TIFFs into Artizen and produce a full 32-bit per colour pixel HDR image and then tone-map.

Extreeeeeeemely time consuming, but can produce some great results if you persist!
(Hint: after spending a looong time with HDR I've got better at recognising when you don't need HDR!!)

Matt

It's actually Professor Matt "Matic" from Fireball XL5 A friend gave me the nickname because of the specs and the love of pure maths
Matt

* Extra 2mm - it's the difference between 24mm and 28mm in film days
* Brighter. The constant f/4 makes for a lovely viewfinder image too.
* Bigger. Quite a lot longer actually (doesn't fit into the ER cases), and takes 67mm filters.

That said, the 18-55 stopped down to f/8 or so is really very sharp. Unless you are pixel peeping, or doing huge enlargements you may find it difficult to tell apart from the 16-45. But the 18-55 is mightily compact and hard to beat for portability!

I've used the 16-45 very seriously and have some great 18x12" enlargements from it. Used it with Cokin P size ND-grad filters.

So, to answer your question - it depends If you want wider, it's worth it. If you find the resolution of the 18-55 limiting, then it's probably worth upgrading.

Hope that helps!
Matt

That wasn't me... it was my son
I've updated my avatar for the time being... hope this is better! LOL!
Matt

Which camera?

The only reason I ask is that my K10D had consistent back-focus on all lenses
I see from your signature that you have the *ist-D - try it on that as well.

The wider the aperture, the more critical focus becomes!
There's some info here: https://www.pentaxuser.com/forum/viewtopic.php?t=6126

HTH!
Matt

Correction - *ist-D and *ist-DS

Don't hold out too much hope for TTL on the K20D...
Matt

But with what lens????
It can be 1 degree with the right lens - a 148mm lens according to the website
Matt

Actually I was trying it on another K10D, not my own So, alas, I don't have any images to show for it.
Matt

Had a quick go on the Sigma at the weekend...
It's very big, and heavy(ish). Wasn't too bad using hand held in sunset light on the K10D with a grip and SR. Like all the Sigma EX lenses, it's well built, and the image quality is excellent too! Focus is quick and quiet too

As has been said, it's not exactly a "walk-about" lens, and the 80-320 fills that. It really depends what sort of photography you are intending to do...

Matt

That was too cruel
Those shots look wonderful!

My only consolation was this blog I read today: http://paulindigo.blogspot.com/2008/01/technical-knowledge-is-not-that.html

(Trying to convince myself I don't need new lenses!! LOL!)

Matt