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Megapixel difference.... What do 8, 16, 20.7 megapixels actually mean?


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Old 08-12-2014, 12:28
Scrufox86
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Hi all. Right I am trying to get my first smartphone and one with a brilliant camera however I do not understand what megapixels mean or if the higher equals better etc. Could anyone give me any information to clarify what all these 8mp, 16 mp etc mean?

Does a 16mp camera mean it is better than an 8mp one just because it is a higher number or is that just a myth and a way for stores to sell higher megapixel smartphones?

Is the Galaxy s5 mini camera worse than the sony xperia z3 compact camera? (for example)
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Old 08-12-2014, 12:36
Stuart_h
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megapixels refers to the number of pixels that actually make up the image. There are lots of other things that need to be taken into account when comparing camera and image quality though so 16mp isnt necessarily better than 12mp (for example). One of the benefits of increasing the megapixels is that when you zoom in you can still maintain a good quality (for cropping parts of photos) but this quality is still dependent on the sensor, the lens, the flash etc etc.
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Old 08-12-2014, 12:37
chenks
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more megapixels in theory means better, but in reality it's not always the case.
in terms of smartphone cameras, they are what they are... ie cameras on a phone.

if you want brilliant photos then you need a proper camera with a proper lens.
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Old 08-12-2014, 13:34
clonmult
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if you want brilliant photos then you need a proper camera with a proper lens.
This really makes no sense. What counts as a "proper lens"?

If you mean your average compact camera, possibly with a large zoom range - the sensors in those is often the same/similar size as to that found in a mobile phone.

In most cases, the pixel count is meaningless. You'll often find that an 8mp sensor can give image quality similar to a 16mp sensor (ie. iPhone 6vSGS5). The only exception to this are the Nokia 808 and 1020. Both of which collate a 38mp image down to a 5mp image with greater clarity.

Nokias other pureview devices are only attempting to leverage the name, they give no advantage.
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Old 08-12-2014, 14:17
chenks
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This really makes no sense. What counts as a "proper lens"?

If you mean your average compact camera, possibly with a large zoom range - the sensors in those is often the same/similar size as to that found in a mobile phone.
the statement i made stands.
it makes perfect sense if English happens to be the first language of the person reading it.
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Old 08-12-2014, 14:21
Scrufox86
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more megapixels in theory means better, but in reality it's not always the case.
in terms of smartphone cameras, they are what they are... ie cameras on a phone.

if you want brilliant photos then you need a proper camera with a proper lens.
Hmm so the megapixel number does not always mean better? So the Galaxy S5 16mp vs the S5 mini's 8mp camera doesn't mean there's a huge difference?

The S3's 8mp vs S5 mini's 8mp is there a difference?
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Old 08-12-2014, 15:16
clonmult
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the statement i made stands.
it makes perfect sense if English happens to be the first language of the person reading it.
No, it doesn't.

What defines a "proper lens"? Anything based on a DSLR or a medium format? Some sort of compact system camera?

Something like the old Nokia 808 can readily better a typical compact camera, that some would say has a "proper lens".

A well designed prime (ie. a mobile) can give better results than a cheap compact with a large range zoom (which normally gives lousy results).
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Old 08-12-2014, 15:22
clonmult
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Hmm so the megapixel number does not always mean better? So the Galaxy S5 16mp vs the S5 mini's 8mp camera doesn't mean there's a huge difference?

The S3's 8mp vs S5 mini's 8mp is there a difference?
The majority of the time, the pixel count has no bearing on quality. It can have a bearing on resolution, but it always depends on how well the phone handles the data.

For a comparison, you can use the gsmarena camera comparison tool ;

http://www.gsmarena.com/piccmp.php3?...&idPhone3=6378
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Old 08-12-2014, 15:38
tdenson
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In my opinion once you get to 8MP you start to reach the law of diminishing returns and any picture quality difference is down to optics and software. There is one benefit of high mega pixel count i.e. what has already been said - you can zoom in to a degree without sacrificing quality. However, there is also a big disadvantage to high pixel count which is large resulting file sizes of the images. I've lost count of the number of times I've had to explain to people why their emails with multiple pictures are failing to send, and then having to explain how they can reduce the size.
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Old 08-12-2014, 15:52
corf
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In my limited experience, megapixels mean nothing - and hardware quality means everything.
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Old 08-12-2014, 16:00
d'@ve
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In my opinion once you get to 8MP you start to reach the law of diminishing returns and any picture quality difference is down to optics and software.
Even moreso.

I had a 6 megapixel DSLR ten years ago and the best pics it produced were of better technical quality than any and all cameraphone pictures taken these days, irrespective of the pixel count. In difficult conditions (very bright, dark, fast moving, distant etc. etc., the differences are even more dramatic.

But of course, it isn't only technical quality that makes a good photo, though for any given photographer, it usually helps.
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Old 08-12-2014, 23:01
clonmult
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Even moreso.

I had a 6 megapixel DSLR ten years ago and the best pics it produced were of better technical quality than any and all cameraphone pictures taken these days, irrespective of the pixel count. In difficult conditions (very bright, dark, fast moving, distant etc. etc., the differences are even more dramatic.

But of course, it isn't only technical quality that makes a good photo, though for any given photographer, it usually helps.
I'd be interested to compare your 6mp DSLR against an 808 in 5mp mode. Its probable that the 808 will equal your DSLRs basic imaging - obviously lenses will give you a greater range of flexibility.

I only say this having compared the 808 against my old DSLR (10mp, Sony Alpha), and it was a pretty even match between the two.

And those difficult conditions will be difficult for an older DSLR; mine sucks in low light/no flash conditions. I've made great use of an external flash at times (indirect, diffused, etc.), but when it came to taking shots of my son at an indoor karting track ... I was aching for a newer model with improved low light capabilities.

In my opinion once you get to 8MP you start to reach the law of diminishing returns and any picture quality difference is down to optics and software. There is one benefit of high mega pixel count i.e. what has already been said - you can zoom in to a degree without sacrificing quality. However, there is also a big disadvantage to high pixel count which is large resulting file sizes of the images. I've lost count of the number of times I've had to explain to people why their emails with multiple pictures are failing to send, and then having to explain how they can reduce the size.
Interesting points ....

I always hark back to the 808, but that is still pretty much the only mobile that can truly replace a dedicated compact camera. The sensor on it is huge - iirc each individual pixel is larger than anything in the iPhone or SGS. The 1020 isn't bad, it just isn't as good as the 808 - camera startup too slow, shot to shot is too slow, colour balance is still slightly out of kilter. Pureview, at least in those two variants, does allow for a usable amount of zoom (or cropping, depends on your point of view) without major loss of quality.
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Old 09-12-2014, 10:12
grumpyoldbat
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This article might help to understand the things to look for in a smartphone camera:

http://mobilementalism.com/how-to-bu...-camera-phone/
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Old 09-12-2014, 10:38
clonmult
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This article might help to understand the things to look for in a smartphone camera:

http://mobilementalism.com/how-to-bu...-camera-phone/
That is an OLD article! Photos of the old N73 and Sony Idou .... so whilst some of the text is accurate, the figures quoted are definitely not right.
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Old 09-12-2014, 17:14
grumpyoldbat
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That is an OLD article! Photos of the old N73 and Sony Idou .... so whilst some of the text is accurate, the figures quoted are definitely not right.
Yes, but as you say, the principles are the same. Quality of sensor, type of flash, lens/aperture size... essentially what has already been said - megapixels are not the key. I just wanted to find something that would help the OP by explaining a little of the theory of photography.
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Old 09-12-2014, 17:39
Scrufox86
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Ok so taking all the information you have all kindly given I am getting that there is not much difference between the z3 compact camera and the galaxy s5 mini's even though the z3 has a 20.7mp versus the s5 mini's 8mp camera?

This is really helping me decide on a smartphone. I had narrowed it down to three choices and recently ruled out the htc one mini 2 due to various things like non-removable battery, known overheating issues and not water or dust proof plus apparent lagging with apps. I am now down to Z3 compact and S5 mini and the only thing really halting my decision is the camera on the phone. As I will hopefully be having the smartphone for at least 2 years I would like a decent camera on the smartphone.

All the megapixels stuff didn't really mean anything to me and the little I had read was that the more mp then the better the camera but this is not the case. Also I think I read somewhere that Nokia smartphones had 41mp camera which to me was a bit "wow must be brilliant" then I heard from someone I know that apparently it is a let down as the phone really takes pictures as 5mp not 41mp. I am guessing it is similar with the Z3 compact and that the pics are somehow reduced to lower megapixel pictures so maybe 5-8mp? In that case it would not be better than the S5 mini in this area. I am very close to a decision now. Thank you all for your help.
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Old 09-12-2014, 18:01
Gigabit
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It's all about finding a balance.

The iPhone 6 'only' has an 8MP camera but the optics are excellent so the photos produced are fantastic.

Whereas the Samsung Galaxy Note 4 has a 16MP camera but the optics are worse then the iPhone so the pictures produced are worse. However, you can crop more of the image without losing as much quality as the iPhone's photos.
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Old 09-12-2014, 19:38
Rodney McKay
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Ok so taking all the information you have all kindly given I am getting that there is not much difference between the z3 compact camera and the galaxy s5 mini's even though the z3 has a 20.7mp versus the s5 mini's 8mp camera?

This is really helping me decide on a smartphone. I had narrowed it down to three choices and recently ruled out the htc one mini 2 due to various things like non-removable battery, known overheating issues and not water or dust proof plus apparent lagging with apps. I am now down to Z3 compact and S5 mini and the only thing really halting my decision is the camera on the phone. As I will hopefully be having the smartphone for at least 2 years I would like a decent camera on the smartphone.

All the megapixels stuff didn't really mean anything to me and the little I had read was that the more mp then the better the camera but this is not the case. Also I think I read somewhere that Nokia smartphones had 41mp camera which to me was a bit "wow must be brilliant" then I heard from someone I know that apparently it is a let down as the phone really takes pictures as 5mp not 41mp. I am guessing it is similar with the Z3 compact and that the pics are somehow reduced to lower megapixel pictures so maybe 5-8mp? In that case it would not be better than the S5 mini in this area. I am very close to a decision now. Thank you all for your help.
As others have pointed out the mega pixel issue is just one element. Think of a racing car, it's not just the engine, but the brakes, the steering and the suspension that all add to the overall performance.

But also, a racing car will be designed for specific things be it endurance, race tracks or rallying.

What sort of photography are you into, for example is a good built in flash essential? Good low light performance, do you mostly display images on a TV screen or print them out?

Do you own any current 'traditional' cameras and if so what features do you value in those?
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Old 09-12-2014, 20:06
jonner101
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It's all about finding a balance.

The iPhone 6 'only' has an 8MP camera but the optics are excellent so the photos produced are fantastic.

Whereas the Samsung Galaxy Note 4 has a 16MP camera but the optics are worse then the iPhone so the pictures produced are worse. However, you can crop more of the image without losing as much quality as the iPhone's photos.
I can't compare it to the Samsung, but the camera on my iphone 6+ is surprisingly good, especially compared with my nexus 5. The focusing performance is excellent. It also makes a good video camera as it has excellent optical stabilisation.

I think the optics and processing are more important. In fact in some cases more megapixels can make things worse as it can lead to more noise in low light.

dxo mark is one the most highly regarded digital camera tests, so go here to see where your phone ranks.

A decent DSLR though with a good lens will blow away any mobile phone camera, if you use it properly.
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Old 09-12-2014, 21:20
The Lord Lucan
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Bigger is better.. Ie DSLR is bigger than a phone. It wins.
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Old 09-12-2014, 22:33
Anika Hanson
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I can't compare it to the Samsung, but the camera on my iphone 6+ is surprisingly good, especially compared with my nexus 5. The focusing performance is excellent. It also makes a good video camera as it has excellent optical stabilisation.

I think the optics and processing are more important. In fact in some cases more megapixels can make things worse as it can lead to more noise in low light.

dxo mark is one the most highly regarded digital camera tests, so go here to see where your phone ranks.

A decent DSLR though with a good lens will blow away any mobile phone camera, if you use it properly.
The nexus 5 had a crap camera. I've not had the chance to put the camera on my 6 plus through its paces yet so I don't know how it compares to the S5 overall. So far I've only tested it indoors in well lit places. It takes better pictures than the S5 in those situations, but outdoors it remains to be seen. I'm really eager to see how it does outdoors because the S5 was really good. So far I've been impressed with the few pictures that I've taken.
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Old 09-12-2014, 22:47
d'@ve
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I'd be interested to compare your 6mp DSLR against an 808 in 5mp mode. Its probable that the 808 will equal your DSLRs basic imaging - obviously lenses will give you a greater range of flexibility.

I only say this having compared the 808 against my old DSLR (10mp, Sony Alpha), and it was a pretty even match between the two.

And those difficult conditions will be difficult for an older DSLR; mine sucks in low light/no flash conditions. I've made great use of an external flash at times (indirect, diffused, etc.), but when it came to taking shots of my son at an indoor karting track ... I was aching for a newer model with improved low light capabilities.
No, there is no comparison except at computer screen sizes, and even then a DSLR clearly wins. A Spanish site did a comparison between two 40MP cameras: the Nokia 808 and the Pentax 645D DSLR, released in early 2010.

Google Translated comparison

Here are two photos of the same scene, different in coverage only because the lens focal lengths were not quite the same but when viewing them at full size, the differences are dramatic.

808 photo 40MP

645D photo 40 MP

I copied both photos into my photo editor and reduced them to 6 MP. The differences are still dramatic. Then, I equalized their sizes so they covered exactly the same angle of view and reduced them to 1.5 MP (less than HD video resolution) and there is still a (smaller) difference between them, with the Pentax again winning.

Chalk and cheese - but obviously, for full frame snapshots on computer screens (no cropping) it may not matter too much. My old 6MP DSLR definitely took clearer sharper and more contrasty photos than the 808 does and that ignores the benefits of having things like fisheye, other extreme wideangle, long telephoto lenses, depth of field control and low light shots. But to be fair, you couldn't stick it in your shirt pocket, send text messages, make phone calls or go on the internet with it... phone cams definitely have their place!
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Old 10-12-2014, 08:30
chenks
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The nexus 5 had a crap camera. .
does it?
i've got a nexus 5 and the camera certainly isn't "crap".
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Old 10-12-2014, 08:33
chenks
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I can't compare it to the Samsung, but the camera on my iphone 6+ is surprisingly good, especially compared with my nexus 5. The focusing performance is excellent. It also makes a good video camera as it has excellent optical stabilisation.
that's not really a fair comparison though.
to make it fair you'd need to compare the 6+ with the nexus 6, as they are both the current flagship models.

an valid nexus 5 comparison would be the iphone 5s.
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Old 10-12-2014, 12:33
Batch
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In my opinion once you get to 8MP you start to reach the law of diminishing returns and any picture quality difference is down to optics and software.
Agreed. There is also the factor of what most people do with camera phone images.

Most of mine are straight onto facebook, a few get 6x4 printed and one or two larger prints. Yes when cropping and zooming its nicer to have more resolution (detail), but I really don't do a lot of this. I bet I could have a good 4 or 5 megapixel camera phone and it would make no difference to the way I use the 8MP I have now.

For more "up close" zooming I use a compact camera with high optical zoom anyway. Its good enough usually.
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