CMOS technology

[shawn_hooper]

I?m trying to find out what the difference is between a 10MP full frame and a

10MP ?small? frame digital body. For example Canon has the 5D (12MP) and the

Rebel XTI (10MP) respectively. How does this effect the pixels? By size? Are

they more tightly packed on the Rebel? Or less dense on the 5D? Let me know

if I need to elaborate more.

 

Thank you,

Shawn Hooper

[ellis_vener_photography]

let's see: same number of grains of sand but a smaller beach...

 

AH! the individual grains of sand must be smaller!

[shawn_hooper]

So what does this mean for the "full frame" cameras with bigger "grains"? Why don't they put the more tightly packed sensors into the bodies now? (Meaning change the size of all to full frame.) And have all full frame cameras?

Not trying to be a PITA, just trying to understand.

 

Thanks,

Shawn Hooper

[roger_smith4]

Try searching the archives for "full frame" or "sensor size."

[ronald_moravec1]

Larger grains (pixels) are more sensitive to light and show less noise and more detail given all other things are equal.

 

If you are restricting to small prints, say 8x10, there will not be much difference all other things being equal again.

 

All things being equal means you do not use the kit lens on the Rebel and an L lens on 5D and you use both at the lowest ISO setting.

 

The larger pixels allow you to boost ISO setting with less noise.

 

The full frame sensor camera are much better built and will withstand profesional use. The Rebel is a lightweight plastic camera, but will work for most amateur use over the expected lifetime.

[wigwam jones]

Shawn,

 

The differences between a larger and a smaller 10mp sensor are primarily down to these:

 

1) The larger sensor should exhibit less 'noise', since when the photosites (receptors or 'pixels') get crammed closer together, noise goes up.

 

2) The larger sensor does not have a 'crop factor' to deal with - so a 28mm lens (on a 35mm film camera) is still a 28mm lens from the point of view of field of vision. On the smaller sensor, a 28mm lens effectively becomes a 42mm (on a 1.5 crop-factor camera).

 

As to why they don't just put more photosites into the larger sensors, we're back to the digital noise problem again. I'm sure they will do so in time, when the tech gets better, which it most likely will.

[gwebster]

Shawn - take a look at this <a href="http://www.photo.net/bboard/q-and-a-fetch-msg?msg_id=00Jwae&tag=">discussion</a> and <a href="http://www.photo.net/bboard/q-and-a-fetch-msg?msg_id=00K1ui">this one</a>

<p>

Gordon

[mark u]

Here's a discussion of some of the issues:

 

http://www.cambridgeincolour.com/tutorials/digital-camera-sensor-size.htm

 

You can find more on some of the topics here:

 

http://www.cambridgeincolour.com/tutorials.htm

[john schroeder]

All things being equal the bigger the sensor the better. The problem is all things are NEVER equal. A full frame sensor needs the highest quality lenses to achieve the best image quality. Light needs to strike a sensor nearly straight on. With cheaper lenses the light at the outer edge is coming in at a greater angle and will cause pronounced edge softness and light fall off. This wasn't a problem with film only with digital. By using a cropped sensor you are only using the center of the image circle where the light is coming in straight. The larger sensor will have larger photo sites. Bigger eyeballs see better but the larger sensor costs more. The cropped sensors deliver excellent results. You will only see a difference if you are printing very large (24x36). There are lenses available that will give you the angle of coverage needed for either size sensor. The whole CMOS vs. CCD argument is just marketing whitewash. The technologies are essentially equal now. Canon pushes CMOS because thats what they build. So... If you have a bag of Canon primes and "L" series zooms, go with the 5D. If you have standard quality zooms, and don't want to upgrade your glass, then the cropped sensor will give you better results. It's a better match to your lenses. The 30D or the Rebel would be a better choice. Better glass will always give you a better picture no matter which body you put it on. It is smarter to spend money on lenses than on bodies. You will get better pictures using "L" series lenses on the Rebel than if you used cheap lenses on the 5D. Always remember the person holding the camera is the biggest determining factor. It's the cook not the pot that makes dinner!

[leicaglow]

I'm not sure a blanket answer of "larger sensors are better" is valid in this discussion. I have owned a Nikon D200 for over a year (10.2 Mp DX sensor size). I recently added a Canon 5D with some fast lenses to my arsenal. I admit I haven't done a lot of comparison yet, but here's what I see so far:

 

- The D200 seems to give slighly less visible grain on larger prints (I sometimes print as large as 44x66"). I.e. the 5D has a very slightly more pronounced grainy appearance.

 

- The D200 seems to render subtle shadow detail and colors better.

 

- The 5D is definitely better for high ISO shooting without noise.

 

- The 5D is better at rendering subjects where I want high contrast and vibrant colors.

 

- Comparing two shots together at screen resolution size and on 8x10 prints, I could not say one or the other is a clear winner. I also can not explain why my results are the way they are, but it is what I am seeing.

[shawn_hooper]

WOW! Thanks guys. (Especially Mark U., that site is impressive.) I already have "a few" Canon lenses. Some "L", some not. So I will go with a Canon, either the 5D or 1DS Mark II. But a Nikon friend was asking me this question, and, coming from the film realm, I had NO idea. So I'm "relearning" photography.

 

Thanks for all the help,

Shawn

[jimstrutz]

For many of us, the biggest difference is price. Full frame sensors raise the camera price considerably. For instance compared to the 30D, the 5D has a somewhat better autofocusing system, but it's mostly the sensor that drives the price up more than double. I'm quite sure the production costs of the FF sensor don't really justify the additional $1500, but since they have the market cornered, why not make the most of it. There are some very obvious benefits to FF, and as long as people are willing to pay for it...

 

On the other hand, there are advantages to the smaller frame cameras as well. Like all your tele lenses act 1.3 to 2 times as long. That's not what's really going on, but the effect seems to be there. The other advantage is the potential for smaller cameras and lenses, and this is being realized in some bodies and some lenses, but not all.