How many megapixels do I need?

MrsDrink

Ok so I'm looking at buying a tablet to replace my Sony ericson smart phone. I'm umming and ahhing between a Sony Xperia z tablet and an iPad of some description. Let me explain. I have always preferred Sony as phones, I like their menu system and they've always had good cameras in them (for my needs). But I also like apple and have a Mac laptop. Basically one of the deciding factors is going to be the tablet's camera. At the moment I have 2 good cameras (a digital fake SLR 12 mega pixels, and a good compact). But sometimes I need/want to take a photo on my phone (to be tablet). I'm talking about pictures to share on facebook/Flickr as well as say scenery photos to print out or put in a printed photobook. My current set up has served me well. I have good cameras for proper photos and my phone for other shots. I currently have 8 megapixels on my phone but is it needed? Would an ipad's 5 (I think) be enough (bearing in mind I print them to upto a4)?

Thanks for any advice. Sorry if I've made any typos. I'm writing this on my phone - another reason why I'd like a tablet.

wiogs

Mega pixels are only part of the story.

You could have 25 but with a horrible bit of plastic in front of it it could be worse than one with 2.5.

Try and have a look at some sites which review the tablets you are interested in to see what photos actually look like.

MrsDrink

Thanks. Of course I'll also pop in to a shop and have a play. But all else being equal would 5 megapixels print out ok upto A4? Thanks.

wiogs

I would personally prefer more, all things being equal.At least 6

paddyrg

Broadly speaking, print qualities of 300DPI and higher are what you use for print. Magazines usually allow for 300DPI quality. A4 is about 10x12", so 3000 x 3600 dots, so 10MPx. HOWEVER that is for typesetting a commercial magazine. 5MPx will work beautifully at A4 for most domestic printers. The human eye resolves to approx 3MPx if it was a camera (but it has the best image processing in the world!).

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yangptangkipperbang

http://renderinglight.com/welcome/?p=3

Johnmcl7

MrsDrink wrote: »

Thanks. Of course I'll also pop in to a shop and have a play. But all else being equal would 5 megapixels print out ok upto A4? Thanks.

Megapixels really mean nothing as it's simply the number of pixels, it gives basically no indication of the quality as you could have 5 million pixels of garbage. I have large prints from my old 5MP DSLR which are superb quality but I wouldn't print anything particularly large from my 8MP phone camera, the quality is not bad in good light but in anything less there's a lot of noticeable noise and compression artifacts in the picture.

The 5MP camera in the Ipad is the same as the older one in the Iphone 4, it isn't as good as the current crop of phone cameras but it depends on what conditions you'll be using it in as to how usable the output is. And your preference of course, it's mostly up to you how acceptable or not the quality is.

John

Johnmcl7

paddyrg wrote: »

Broadly speaking, print qualities of 300DPI and higher are what you use for print. Magazines usually allow for 300DPI quality. A4 is about 10x12", so 3000 x 3600 dots, so 10MPx. HOWEVER that is for typesetting a commercial magazine. 5MPx will work beautifully at A4 for most domestic printers. The human eye resolves to approx 3MPx if it was a camera (but it has the best image processing in the world!).

If

While it's difficult to measure and compare to camera sensors as the human eye works very differently, rough equivalents put the human eye capable of resolving between 300 and 600MP of resolution and capable of distinguishing additional detail on very high resolution prints over low resolution versions so it's not even remotely accurate to claim the human eye can only resolve 3 megapixels. (similar to the 60fps myth which is also completely false, again the human can resolve far beyond that).

John

Pinkypants

Depends on the size you what to print and how far away it'll be viewed from. An A4 print on the wall the that you view from 2 feet away probably needs half decent resolution.

But a bill board, which is massive but viewed from a great distance doesn't have to have the same resolution.

Norman_Castle

As picture quality is set by the lens and electronics is it worth using a lower quality camera at its highest megapixel setting?

Lifeforms

Using an ipad to take pictures is very cumbersome.

It's the same with cameras. it's not the megapixels, it's the sensor. High megapixels, crap small sensor isn't good. And no matter what people might think smartphones and tablets with cameras are not up to a decent digital camera/dslr.

http://answers.yahoo.com/question/index?qid=20130501162322AA4Q9Ju
I know, yahoo answers, but it does give some good reasoning and a potential choice.

I think the ipad mini camera is "good" but it's not "good" compared to my decent digital camera and find it fails in a lot of situations, and it's just plain awkward to use as a camera.

To put it bluntly. Cheap cameras have cheap small sensors that produce awful results if you are looking for high quality print outs.

http://www.digitaltrends.com/photography/image-sensor-size-matters/
This is more about digital cameras, but it does transfer over to tablet/iphone. they're all the same, they need the same bits to work:

Compare the size of a DSLR to a pocket camera or smartphone – the difference is noticeable. From this you can conclude that the larger DSLR will accommodate a larger sensor, and in turn a larger sensor will produce the better picture. This is why resolution doesn’t matter solely, because a more advanced camera with a large sensor will trump the low-end point-and-shoot with a small sensor, even if both sport the same number of megapixels. With a small sensor, the pixels can’t capture as much light, so a pocket camera will produce images that have less dynamic range and never as clean as a DSLR. A camera with a larger sensor will also produce images with less noise, especially at high ISO. Of course, the tradeoff in image quality means more convenience.

^ which doesn't really say printed out at A4 it will be terrible, but it will be different if you used a better camera..