Too Many Megapixels

[TCav]

AndyfromVA wrote:

Hawgwild wrote:

I'm gettin' it all right. But I can't say I really understand it.

I'm saying that I agree with you. Higher pixel densities result in more noise.

But, at higher resolutions,the individual pixels contribute less to the final image. The noisy pixels get drowned out by the accurate pixels. In order for the noise from an errant pixel in a 6 MP imageto have the same impact on a 24MP image, 4 adjacent pixels must all be equally noisy. That won't happen.

Even if there are proportionally more noisy pixels in a 24MP image than in a 6MP image, the noisy pixels are less apparent in the 24MP image, because the individual pixels are less noticeable.

If you were to take a photo with a Nikon D40 using a 100mm lens, and then, from the same vantage point and pointing in the same direction,take a photo with a 24MP APS-C dSLR using a 50mm lens, and crop it to 50%, the second image would contain more noise (all other things being equal.)

But why would someone do that?

[fldspringer]

I think we need to step back and look at the original post. Its 12.4 million pixels on a 1/2.3 sensor with a lens wide open at the long end of f5.8, and yes, its too many MP and I don't think the arguments apply. Can the lens resolve anywhere near that level? How far into diffraction limits is f5.8 when the sensor is 1/2.3 with nearly 50mp/sq.cm.

Yes, too many MP. ISO 6400? Only thing missing is 24x zoom. Oh, that's the X70.

The camera would be a better camera with half than number of pixels. I disagree with anyone that says differently.

Greg

[peripatetic]

More pixels cause more noise at the per-pixel level, so when you view at 100% you see more noise, but that is NOT comparing like-for-like. When you compare like for like you do not see more noise e.g. a set web resolution or the standard print size of 8x10 viewed at 25cm.

Read the DXO links again.

It is not too many pixels.

http://theonlinephotographer.typepad...be-enough.html

Additionally, by putting so many pixels on the sensor the need for an AA filter goes away. Just because you are diffraction limited does not mean that additional detail cannot be captured. It can. Diffraction limitation is not a wall beyond which nothing can pass. It is a point beyond which you suffer degradation the further you go; but if you can improve other areas of the imaging chain then overall quality can still be improved.

The camera would be a better camera with half than number of pixels. I disagree with anyone that says differently.

I don't understand. Are you are simply saying that you disagree with anyone who has a different opinion to you? (See http://en.wikipedia.org/wiki/Tautology_(logic)) Or are you are saying that you have made up your mind and are immune to evidence, reason and argument?

Read down to the bit that starts: "Are smaller pixels.."
http://www.cambridgeincolour.com/tut...hotography.htm

[fldspringer]

peripatetic wrote:

I don't understand. Are you are simply saying that you disagree with anyone who has a different opinion to you? (See http://en.wikipedia.org/wiki/Tautology_(logic)) Or are you are saying that you have made up your mind and are immune to evidence, reason and argument?

Read down to the bit that starts: "Are smaller pixels.."
http://www.cambridgeincolour.com/tut...hotography.htm

I'll start with this:

http://c.img-dpreview.com/0106942-01.jpg


I'll assist you in your understanding.

I would not buy that camera. You may put theory after theory before me, but it isn't theory, but application.

This is a camera I can buy new for $150. How good is the lens for $150. How good is the camera at getting 12mp of data off chip onto card for $150. ISO6400 on a 12mp 1/2.3 sensor at what dynamic range? What is the DR at base ISO? BTW, what happens to DR as pixel size decreases.

The bottom line is the camera would be more functional with fewer pixels. A bit more DR which would be needed. Quicker shot to shot due to less data, and IMHO, you will not be able to tell a difference in print/display at half the resolution. Theory is theroy, but where rubber hits the road in the real world, this cheap camera is beyond the point of diminishing returns.

Next, why not 50mp in this camera? How about 100mp? How do you think write time would affect the camera? Do you REALLY think there would be a positive change in IQ? For the record, I do not think it would be functional at 100mp. I think the only difference to IQ would be the lower DR.

Bottom line is, for ME, the camera would be better at half the resolution. It would be more functional, and you would be hard pressed to see ANY difference. I will not be convinced differently, even with another dozen articles.

The photo above is the 4.9 MP E-1 and it won one of the DPR challenges. Would it be better with 10mp? Yes, but you would have to have yournose right against the print to see it.

Greg

[fldspringer]

peripatetic wrote:

It is not too many pixels.

http://theonlinephotographer.typepad...be-enough.html

The article mentions 400mp.

I don't see a need, but interestingly, the camera mentioned in the OP has a density of 42mp per sq cm.

If that was multiplied out over the area of a FF sensor, that sensor would have 368mp.

Greg

[Hawgwild]

I always said if I could learn just one thing a day, I would be happy. Well, thanks to this thread, I'm good for about a year.LOL..

You still there, Andy??

[fldspringer]

Hawgwild wrote:

I always said if I could learn just one thing a day, I would be happy. Well, thanks to this thread, I'm good for about a year.LOL..

You still there, Andy??

I guess we could just say that there is some difference of opinion, Andy.

Greg

[AndyfromVA]

Hawgwild wrote:

I always said if I could learn just one thing a day, I would be happy. Well, thanks to this thread, I'm good for about a year.LOL..

You still there, Andy??

Yeah and I still have my doubts about 12 mp's in a tiny sensor.

[Alan T]

I may have missed it in this thread, but let's not forget that you need both a good sensor and a good lens for a good result.

Smaller cameras have very great variability in lens quality, that isn't automatically directly correlated with price. If your image isn't particularly sharp to start with, the sensor doesn't matter so much. Conversely, an excellent lens will allow you to get away with fewer pixels. In the highly competitive mass market for small cameras at low prices, clearly compromises on both will be made.

For fussy people like me, my local camera shop keeps a huge folder of giant enlargements on the counter, printed by them from their recommended cameras' images, so that customers can see for themselves.They place more emphasis on lens than on pixels in making their judgements.

[TCav]

Alan T wrote:

I may have missed it in this thread, but let's not forget that you need both a good sensor and a good lens for a good result.

Smaller cameras have very great variability in lens quality, that isn't automatically directly correlated with price. ...

Since the discussion has broadened into the area of lenses, let's also remember that lenses for P&S digicams are simpler and cheaper to design and manufacture, and, coorespondingly, simpler and cheaper to make well. Making room for the mirror box makes the design and manufacture of SLR lenses more expensive and more complicated. Compare the Tamron 18-270 VC (35mm film equivalent focal length on a Canon dSLR: 29-432mm) ($599) with the Canon SX10 IS (35mm film equivalent focal length: 28-560mm) ($355) (That's $355! Not just for a lens, BUT A WHOLE CAMERA!)

Once again, the problem with this discussion is that all things are not equal.