Pixels - Are You Getting Enough?

Finn said:
I'm not sure I understand this.

Jagged edges are a symptom of aliasing, where your sample rate is too low for what you are sampling. For instance if you have a smooth edge at an angle one pixek is inside the edge, one outside so you get a jagged "stairstep" effect instead of the smooth edge. One technique to get rid of the effect is super-sampling. Where effectively you take a much higher res picture and resize it down so the final output pixels rather then just being "inside" the edge and "outside" the edge, end up a blend of the 2 colours.

When you set your camera to a lower res thats exactly what the camera is doing. It doesnt change the size of the sensor, the sensor still captures at the exact same size the camera just resizes that image down before storing it to the memory card. The same operation that you would do on the PC to resize for web. The only advantage of doing it on the camera is that the image gets smaller sooner so you can fit more on the card. Hoever you can get more advanced algorithms for the PC than the camera can manage to you could actually get a better output result than the camera can do.
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Hi Finn, sounds like you do know your stuff.
I guess my own "thing" regarding this jagged effect came about when I ran off a series of test shots a couple of years back using a Fuji S5600. One at high resolution, at mid and at the lowest. All of them pictures were resized using the same resize settings (800 x 600) and then sharpened and the mid-resolution picture appeared to have come out looking the best. And with that in mind, it became like a "personal obsession" from there onwards. :D I'm just being a little old fashioned and funny when it comes to things like this.
Like for instance, I also think about how much space that could be freed up on a memory card. But then agan, with today's cards and how cheap they are, they could still store thousands of high res pictures in any case!
 
Well there is a lot to be said about a multi-stage resize process, eg not going to the final destination size in one step but having one or more intermediate steps. It would have been interesting to have repeated your test taking the highest res image, resizing it (on PC) down the the same size as the medium version and then to you 800x600 destination size.

Given your resizing down for the "final print" the differences in how you do it are going to be largely negligible and rather subjective at that. If your happy with your process then by no means change it I just didn't agree with the claim that a resize in camera is somehow different to a resize on the PC :)
 
We live in a world where everything has a pound/dollar sign slapped onto it. To get YOUR hard earned cash, the products have to be more attractive than the competitors. That's the ONLY reason cameras are getting larger mega pixels - it sells products in a highly competitive environment.

Pro's have been using up to 12 MP cameras for a long time, producing for large print with no problems whatsoever. For the very rare, billboard sized prints, inter/extrapolation software such as Genuine Fractals are used to increase the scale of the image. As long as the sensor retains high IQ, you can scale to, quite frankly, ridiculous sizes.
 
russbates said:
With the added bonus of an unbreakable body, a few more frames per second and a camera that actually auto focuses!!!! :p

(Yeah i used a 5D for a bit)
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Yeah, 5D AF and frames rate is a bit slow sometimes but you surely must WANT to break it. :D
 
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