Do people really need 10megapixels point-and-shoot cameras?

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DBL

Platinum Member
Mar 23, 2001
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Originally posted by: Howard
Originally posted by: DBL
These cameras can resolve to their stated resolution UNDER THE PROPER CONDITIONS regardless of the size of the lens.
What are you talking about? How does the resolution change?

Take a picture at ISO 100 and ISO 800 with a 10mp p&s. While the camera will save a 10mp image in both cases, only the ISO 100 picture would be somewhat close (if the shutterspeed and light were optimal) to actually resolving to the full potential of the camera.

The bottom line is that a P&S rarely takes a picture which actually comes close its max resolution in the real world.

 

ElFenix

Elite Member
Super Moderator
Mar 20, 2000
102,402
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Originally posted by: DBL
Originally posted by: Howard
Originally posted by: DBL
These cameras can resolve to their stated resolution UNDER THE PROPER CONDITIONS regardless of the size of the lens.
What are you talking about? How does the resolution change?

Take a picture at ISO 100 and ISO 800 with a 10mp p&s. While the camera will save a 10mp image in both cases, only the ISO 100 picture would be somewhat close (if the shutterspeed and light were optimal) to actually resolving to the full potential of the camera.

The bottom line is that a P&S rarely takes a picture which actually comes close its max resolution in the real world.

no.
 

DBL

Platinum Member
Mar 23, 2001
2,637
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Originally posted by: ElFenix
Originally posted by: DBL
Originally posted by: Howard
Originally posted by: DBL
These cameras can resolve to their stated resolution UNDER THE PROPER CONDITIONS regardless of the size of the lens.
What are you talking about? How does the resolution change?

Take a picture at ISO 100 and ISO 800 with a 10mp p&s. While the camera will save a 10mp image in both cases, only the ISO 100 picture would be somewhat close (if the shutterspeed and light were optimal) to actually resolving to the full potential of the camera.

The bottom line is that a P&S rarely takes a picture which actually comes close its max resolution in the real world.

no.

That's insightful.

 

DBL

Platinum Member
Mar 23, 2001
2,637
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Originally posted by: Howard
Originally posted by: DBL
These cameras can resolve to their stated resolution UNDER THE PROPER CONDITIONS regardless of the size of the lens.
What are you talking about? How does the resolution change?

Also, I should point out that I did not actually say that the actual resolution changes just that the effective resolution changes.

 

Howard

Lifer
Oct 14, 1999
47,982
11
81
Originally posted by: DBL
Originally posted by: Howard
Originally posted by: DBL
These cameras can resolve to their stated resolution UNDER THE PROPER CONDITIONS regardless of the size of the lens.
What are you talking about? How does the resolution change?

Also, I should point out that I did not actually say that the actual resolution changes just that the effective resolution changes.
How are you defining effective resolution?
 

DBL

Platinum Member
Mar 23, 2001
2,637
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Originally posted by: Howard
Originally posted by: DBL
Also, I should point out that I did not actually say that the actual resolution changes just that the effective resolution changes.
How are you defining effective resolution?

Why is that really necessary? It's logical.

All other things being equal, effective resolution will decrease to a certain extent if
ISO increases
Pixels decrease
pixel size decreases
available light decreases
etc.

Compared to a DSLR, a p&S is more sensitive to some of these (ISO).

 

LS20

Banned
Jan 22, 2002
5,858
0
0
i dont think that youre entirely confused, but you are really skirting the true technicalities

Originally posted by: DBL
Why is that really necessary? It's logical.

All other things being equal, effective resolution will decrease to a certain extent if
ISO increases
Pixels decrease
pixel size decreases
available light decreases
etc.

Compared to a DSLR, a p&S is more sensitive to some of these (ISO).

 

Rubycon

Madame President
Aug 10, 2005
17,768
485
126
Originally posted by: ThePresence
MP = Penis size.
Didn't you know that?

MP is megapixel not megapenis. :p

Or in the case of most micropenis. :laugh:
 

Cerpin Taxt

Lifer
Feb 23, 2005
11,940
542
126
Originally posted by: LS20
Originally posted by: Garth
I'd be curious to know the actual pixel sizes on the sensor and the optical resolution of the camera's lens(es). It's conceivable (though maybe unlikely) that the optics in the lens could not resolve detail to a level that is smaller than the size of the pixels on the CCD. If that were the case, then the higher pixel count would only capture more of the fuzziness of the lenses -- but what's the point of that?

Additionally, if the pixel sizes are no smaller than those on, say, a 7MP chip, then the only way to capture additional detail is to magnify the image with the lens. Assuming no increase in magnification and no decreasae in pixel size, all you will acquire is a larger frame, not finer detail.

I don't really know very much about consumer or pro-sumer digital cameras, but I would be very surprised to find that the increasing chip resolutions are not due to a decreasing sizes of the individual pixels. That would seem too obvious of a marketing gimmick. I don't have much faith in the camera companies, but well... that would just be too much even for them.


sensors and lenses arent divisible into pixels and cant be described with resolution. a pixel unit is a pixel unit. youre confusing me
A CCD pixel is a sensor. A CCD array is also a sensor.

Lenses have measurable optical resolution.

 

thelanx

Diamond Member
Jul 3, 2000
3,299
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Originally posted by: ElFenix
Originally posted by: Garth
I'd be curious to know the actual pixel sizes on the sensor and the optical resolution of the camera's lens(es). It's conceivable (though maybe unlikely) that the optics in the lens could not resolve detail to a level that is smaller than the size of the pixels on the CCD. If that were the case, then the higher pixel count would only capture more of the fuzziness of the lenses -- but what's the point of that?

Additionally, if the pixel sizes are no smaller than those on, say, a 7MP chip, then the only way to capture additional detail is to magnify the image with the lens. Assuming no increase in magnification and no decreasae in pixel size, all you will acquire is a larger frame, not finer detail.

I don't really know very much about consumer or pro-sumer digital cameras, but I would be very surprised to find that the increasing chip resolutions are not due to a decreasing sizes of the individual pixels. That would seem too obvious of a marketing gimmick. I don't have much faith in the camera companies, but well... that would just be too much even for them.

actually, the lens on most consumer sub-compact cameras is outresolved by a 10 MP sensor. 6 to 7 MP seems to be about all those lenses are good for.

the pixel sites on most 10 MP cameras are physically smaller than the pixel sites on most 6 MP cameras. that is because it is cheaper to shrink the sensor (through moore's law) than redesigning a lens. most ultra compact digicams use a 1/2.5" sensor, regardless of the resolution of the sensor. if the pixels sites themselves were larger, you'd have to use a different lens to get a similar field of view.

and of course, this MP race doesn't necessarily improve image quality. as i said, most lenses are outresolved by the 10 MP sensors. one of the downsides to the ever decreasing size of the pixel sites is that the signal to noise ratio from the sites is decreasing as well. that results in more noise. so, these chips don't capture much more information, and what information there is is increasingly drowned out by noise. try explaining that to little mary jane rottencrotch in best buy when she wants a camera to party with.

part of the reason fuji's super CCD (which features an almost DSLR like noise level) has so little noise is that they use a lower MP sensor that is 1/1.7" (or about 2x the size of a typical compact). that gives it a better signal to noise ratio than its compact competitors. DSLRs have low noise for the same reason (a 10 MP crop frame DSLR sensor has about 6x the physical area of a 1/2.5" sensor)

Very nice points. I agree, I have a sd900 (10 MP compact P&S) and I would definitely trade megapixels for a larger lens.
 

potato28

Diamond Member
Jun 27, 2005
8,964
0
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Originally posted by: Garth
Originally posted by: LS20
Originally posted by: Garth
I'd be curious to know the actual pixel sizes on the sensor and the optical resolution of the camera's lens(es). It's conceivable (though maybe unlikely) that the optics in the lens could not resolve detail to a level that is smaller than the size of the pixels on the CCD. If that were the case, then the higher pixel count would only capture more of the fuzziness of the lenses -- but what's the point of that?

Additionally, if the pixel sizes are no smaller than those on, say, a 7MP chip, then the only way to capture additional detail is to magnify the image with the lens. Assuming no increase in magnification and no decreasae in pixel size, all you will acquire is a larger frame, not finer detail.

I don't really know very much about consumer or pro-sumer digital cameras, but I would be very surprised to find that the increasing chip resolutions are not due to a decreasing sizes of the individual pixels. That would seem too obvious of a marketing gimmick. I don't have much faith in the camera companies, but well... that would just be too much even for them.


sensors and lenses arent divisible into pixels and cant be described with resolution. a pixel unit is a pixel unit. youre confusing me
A CCD pixel is a sensor. A CCD array is also a sensor.

Lenses have measurable optical resolution.

And most P&S CCD's are 1/6th of an inch(very bad quality).
 

Koing

Elite Member <br> Super Moderator<br> Health and F
Oct 11, 2000
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Originally posted by: spidey07
There is never a case where more doesn't mean better.

Image noise anyone? :p

Koing
 

Howard

Lifer
Oct 14, 1999
47,982
11
81
Originally posted by: DBL
Originally posted by: Howard
Originally posted by: DBL
Also, I should point out that I did not actually say that the actual resolution changes just that the effective resolution changes.
How are you defining effective resolution?

Why is that really necessary? It's logical.

All other things being equal, effective resolution will decrease to a certain extent if
ISO increases
Pixels decrease
pixel size decreases
available light decreases
etc.

Compared to a DSLR, a p&S is more sensitive to some of these (ISO).
You dodged the question.
 

Chaotic42

Lifer
Jun 15, 2001
34,778
1,952
126
Originally posted by: Aimster
yes

I want 10MP :)

I don't print anything, but on the computer it looks great.


10? I want as many as physically possible. The sharper the image, the better.
 

AndrewR

Lifer
Oct 9, 1999
11,157
0
0
Originally posted by: DBL
Originally posted by: ElFenix
Originally posted by: DBL
Originally posted by: Howard
Originally posted by: DBL
These cameras can resolve to their stated resolution UNDER THE PROPER CONDITIONS regardless of the size of the lens.
What are you talking about? How does the resolution change?

Take a picture at ISO 100 and ISO 800 with a 10mp p&s. While the camera will save a 10mp image in both cases, only the ISO 100 picture would be somewhat close (if the shutterspeed and light were optimal) to actually resolving to the full potential of the camera.

The bottom line is that a P&S rarely takes a picture which actually comes close its max resolution in the real world.

no.

That's insightful.

A simple answer to what you're spouting, which makes no sense. The resolution of a camera's sensor does not change in some magical way based on the light sensitivity setting. I'm not an EE, but I don't see the connection. Seriously, correct me in detail if I'm wrong.

I agree with your last statement, but that's hardly a bombshell. However, the reason why P&S sensors have trouble with high megapixel count is the same reason why DSLR sensors are hitting a wall with regard to pixel count -- pixel density which causes noise as you increase light sensitivity (ISO). The resolution issues are primary from the quality of the lens. Consumer-grade lenses simply aren't capable of catching enough detail, which someone pointed out above. You can also find the opposite -- exceptional quality lenses can surpass a sensor's ability to resolve the detail they provide.

The solution for noise moves into noise reduction algorithms and sensor construction (CMOS vs. CCD -- looks like Sony might be moving to CMOS incidentally). Some manufacturers use aggressive noise reduction which reduces image noise but wipes out fine detail (Nikon likes this in some of their cameras). So, you might have a lens which can match the resolution of the sensor, but that resolution is smudged in the quest to reduce noise. Others favor higher resolution with higher noise (Sony's Alpha), which might necessitate a noise reduction program like Noise Ninja.

I don't understand it, but these algorithms/choices even affect RAW images in some way. I'd have to do some serious digging to find those discussions I read awhile back so don't ask. On second thought, I'm going to track that down to educate myself. I remember being skeptical when I read it (yes, I know RAW is supposed to capture the sensor's data unmolested). I'm getting too old to remember things that I read...

Speaking of being old, it's late, and I'm exhausted. :D
 

RaynorWolfcastle

Diamond Member
Feb 8, 2001
8,968
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Good Lord, I'll try to shed a bit of light on this topic (pun intended) since there's so much misinformation in this thread.

El Fenix and AndrewR have the basics right. I won't comment on the lens being the limiting factor on a small P&S with a 10 MP camera because, frankly, I don't know the specifics of the lenses and it obviously varies from camera to camera.

With that said, assuming all else is constant, if the size of the sensor stays constant and you increase the sensor's resolution, you end up with a noisier image. This is due to several reasons which include sensor noise, amplifier noise, the nature of light and many more. Since amplifier and sensor noise have only a very weak relation to sensor size, you can assume that they're more or less constant in the event of a photoreceptor size reduction. However, as the photoreceptor size is reduced, the signal it detects is smaller (fewer photons hit each receptor) and so the noise appears larger relative to the signal and you get a noisier picture.

Related to this, the ISO setting on a digital camera will change only the amount of analog amplification of the photoreceptor's signal. Thus when high ISOs are needed (low light) there are few photons that hit the photoreceptor and you have to amplify it a lot. As I said earlier, the noise from the sensor and the amplifier is roughly constant regardless of the input signal. It is therefore entirely possible that the signal is swamped by noise and is completely unusable. Note that in this whole description, nothing about resolution has changed; a 10 MP sensor will be noisier than a 6 MP sensor of the same size assuming all else is equal.

To counter this high ISO noise, camera manufacturers add DSP algorithms in camera which attempt to remove the noise and retain only the signal. This is effective only to a certain extent and will often remove detail as well as noise as explained by AndrewR.

Anyhow, the bottom line is that higher resolution sensors are generally noisier although there are some techniques which attempt to get around it (for example, using 4 actual photo-sensors and considering them a single super-photoreceptor at very high ISO settings, which produces an image with 1/4 the sensor resolution but with less noise).

As an aside, AndrewR, I believe you are right that RAW images relate the sensor data directly without any post processing at all. Heck, RAW image haven't even gone through demosaicking!
 

everman

Lifer
Nov 5, 2002
11,288
1
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I don't understand why megapixels is still important. If you look at the cameras on the mars rovers they are only 1MP, but due to their design they take amazing pictures. Is image quality in consumer level cameras even really increasing measurably anymore even while the pixel count increases?
 

AndrewR

Lifer
Oct 9, 1999
11,157
0
0
Originally posted by: RaynorWolfcastle
As an aside, AndrewR, I believe you are right that RAW images relate the sensor data directly without any post processing at all. Heck, RAW image haven't even gone through demosaicking!

There is something which does affect even RAW image quality with regard to noise reduction. There is no post-processing on a RAW image, but I remember reading on DPReview about some issue which does affect them -- I think it was related to Nikon though applicable to others. I'll dig it up and see if I'm crazy or not.
 

GTaudiophile

Lifer
Oct 24, 2000
29,767
33
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Originally posted by: Pacemaker
Originally posted by: Excelsior
If it means that hot college girls take even better pictures of themselves being naughty that I have to scroll in all directions to even be able to see the whole thing, then sure.

Fixed.

Nominated: Post of the Week!!!
 

RelaxTheMind

Platinum Member
Oct 15, 2002
2,245
0
76
I have this new software integrated into my browser and photoviewer that lets me see the entire picture and blow it up when I choose to. With higher res pics I can crop what I need.

Kind of neat to have for a P&S camera with all the on-the-fly snapshots...

 

DBL

Platinum Member
Mar 23, 2001
2,637
0
0
Honestly, you guys are not really claiming anything different from me. Perhaps my terminology was confusing but I was stating the the "effective" resolution is reduced. I realize that regardless of any setting and/or conditions that a 10mp camera at full resolution will still put out a 10mp image. I was just trying to get at why a 10mp image from a DSLR would be superior to a 10mp image from a 10mp p&s.

I was trying to simplify all the various reason by stating that the "effective" resolution (resolving power) of all 10mp sensors are not created equal. There is a certain "average" that could be determined through some testing and research but it's pretty evident from looking at various pictures from both a p&s and a DSLR of equal resolution, that the DSLR will on average, produce a better picture with finer detail (effective resolution).

Perhaps the one thing I disagree with is those who state that the lenses on these small cameras are being out resolved by the high mp of the internal sensor. While this may true in real world situations (where most pictures are taken), in samples that I have seen which generally include optimal studio lighting, the good small sensor cameras can resolve to their stated resolution. For instance, all else being equal and in optimal conditions, a 10mp p&s will resolve more detail than an 8mp p&s. Doe this mean that a 10mp p&s camera would be beneficial to you? Probably not as the amount of pictures taken in optimal lighting is likely pretty small compared to the total number of pictures taken.