| The obvious difference in image sensors between the | | | | you go in search of extra lenses, you'll quickly learn, |
| D90 SLR and the Canon Rebel T1i is 15.1megapixels, | | | | that more megapixels usually means dropping more |
| and 12.3MP respectively. Using those specifications and | | | | money on higher priced lenses. The lenses meant to |
| applying a bit of thinking would lead most people to | | | | work with high megapixel digital SLR are designed for |
| arrive at the conclusion that the Rebel T1i is probably | | | | higher resolutions, and almost always cost extra. |
| the better deal. | | | | Strangely enough, the lens that's usually supplied (EF-S |
| Unfortunately for a information deluged camera | | | | IS 18-55mm f/3.5-5.6) by the manufacturer with the |
| purchaser, that's simply not accurate. There exist | | | | Canon Rebel T1i, is not one of those that is well suited |
| better image sensors (Canon SLR 40D) that could | | | | at managing large megapixel resolution cameras. I |
| have been used during the design stage. | | | | know it's quite a bit more money, but the Canon |
| I'm certain you've learned in some of my other | | | | 18-200mm EF-S would have been a better lens for the |
| discussions, that lots of megapixels doesn't necessarily | | | | T1i. |
| render into spectacular photographs. The image | | | | If that wasn't bad enough, you may be curious to |
| sensor needs to be designed to cope with more | | | | know, that high pixel density can degrade performance |
| megapixels. | | | | of ISO, diffraction, and dynamic range. I don't know |
| The APS-C sensor used by the Rebel SLR T1i, is | | | | about you, but I'm beginning to think, that getting less |
| actually a bit smaller than the DX type image sensor | | | | megapixels from the Nikon D90 12.3MP for more |
| used by the Nikon D90 DX. Obviously there are | | | | money, may be a better deal for my bank account. |
| different approaches to get extra pixels into a smaller | | | | A time-honored measure of image sensors using |
| sensor. Using smaller pixels, and cramming them closer | | | | RAW data, is offered by DxOMark. Dx-O-Mark has |
| than ever. What were talking about here, is basically a | | | | tested the Canon EOS 50D which employs the same |
| different measurement referred to as pixel density. It's | | | | image sensor as the T1i, and supports my earlier |
| not a spec you'll find branded in plain sight on the | | | | assumptions, that the Nikon D90 produces higher |
| Canon Rebel T1i packaging. The density for the Canon | | | | quality images. The Canon 50D test data should be |
| Rebel T1i is 4.5 megapixels per square cm, but the | | | | very close to the Canon Rebel T1i DxOMark testing, |
| D90 is 3.3 megapixels per centimeter squared. | | | | once it is presented. |
| Crowded pixels is a detractor, but there's more. As | | | | |