Megapixel theory

This recently posted article may (or may not) shed some light on the issues of sensor technology:
http://www.anandtech.com/digitalcameras/showdoc.aspx?i=3290

There's to be a follow-up article that tackles the issue of noise in more depth.

I tried to explain it in this thread

https://www.pentaxuser.com/forum/viewtopic.php?t=7487&highlight=photons

and I'm too lazy to type it out again hope it helps.

that discussion was about sensor size, but if you keep the physical size the same and increase the number of pixels the same effect applies. Smaller pixels = less light hitting each one = greater percentage error = more noise.

Chirpy & Mongoose

Thanks for those links - the AnandTech article is particularly illuminating.

Wow - that's a lot of arguments about megapixels! I agree with most, but I'm reluctant to take them all as gospel truth.

What annoys me is that people, i.e. customers, are led to believe that the compacts with their small lenses can justify the high resolution of 10-12 megapixels. No way!

Just the other day I met a phone seller at Heathrow's Terminal 5, having my K100D on my shoulder. He insisted that he could produce better pictures from the latest Nokia phone camera than I could with my Pentax. I didn't want to enter a longer argument, so my response was a polite I s'pose before walking away.

High megapixels demand better lenses. This is why, according to Pentax, the new Mk II kit lens came out, because the original 18-55mm lens did not have enough resolution to match the 14 megapixels of the K20, again according to Pentax.

I am quite happy with my K100D/6.1 megapixel camera, it seems a good tradeoff between economy and quality. I have never had the need for prints above the A4 format, and the compact file size of about 3 MByte speeds up file transfer and also makes the Photoshop Album run smooth when flipping through the pictures at full screen.

I believe the main issue is to establish ones requirements, and select the equipment accordingly. (And what's the use of the high resolution when we have to reduce the pictures to 800 pixels to post them in the forum?)

It's interesting to note that the Royal Photographic Society specifies sample images of no more than 1024 pixels along the longest side of images submitted by applicants to their Licentiate grade.

Their assessment of the images includes looking for digital pixelation.

What should we learn from this I wonder?

Just to clarify - my point wasn't that the additional pixels made the image better, it was that the newer in-camera image processors was better, and the white-balance was being calculated better, and so on, making the images sometimes seem better...
(Or maybe I'm just buying better compacts, irrespective of MP count... so my opinion here is hardly un-biased - my *MP Optio makes better images than my 4MP Kodak... )

My entry above seems to have been entered twice. How can I delete one of them?

You can delete your message by clicking on the cross top right of the message. I've done it for you.

Might this just be an administrators option? I just see 'quote' and 'edit' on my posts.

Dan

I thought you could delete your own posts, but that may not be the case. In any event, I would eventually see and delete any obvious duplicated posts. It helps to keep things tidy!

I think you can delete your own posts but only if it is the last in the thread, not if someone has posted later in the same thread.