Shop Mobile More Submit  Join Login
The Megapixel Myth by likwidoxigen The Megapixel Myth by likwidoxigen
A tutorial talking about the Megapixel myth with Digital Cameras. Simplified and modified version of The Megapixel Myth by Ken Rockwell.

[link] <-Ken Rockwell, "The Megapixel Myth
[link] <- NY Times reported blows up a 5, 10 and 13mp image and no one can tell the difference.

I need to update this description. With the right skills, and the right know how I got a 3.6MP image printed at 20"x30" and it is absolutely positively gorgeous. And that's when viewed from about 6 inches away, it's stunning.
Add a Comment:
 
Hidden by Owner
:iconlikwidoxigen:
likwidoxigen Featured By Owner Oct 30, 2010
It's a comparison of linear measure and area measure.

To make a square that is twice as big as a 4x4cm square you make it an 8x8cm square because "size" of the final product (as in a photo print) is about linear measure.

An 8x8 square has quadruple the area of a 4x4 square. 64cm^2 vs 16cm^2

You would never order a 24in^2 print but you would order a 4x6 and if you wanted something twice as big you'd look to get an 8x12.

Megapixels are an area measure and MEANINGLESS with regards to the final product from photgraphy (a photo print).
Reply
Hidden by Owner
Hidden by Owner
:iconsounava:
Sounava Featured By Owner Oct 3, 2010   Photographer
A 12MP cam cannot have 8192 pixels in the long side.

12MP = 12000000pixels.

Therefore, number of pixels at the short side = 12000000/8192 = 1465 => Then the image will turn into a panorama :rofl:

3MP cams have 2048x1536 images. 1465 is even less than that :rofl:

12MP cams typically have 4000x3000 resolution. Note that 4000x3000 = 12000000.

I have no idea what the author was thinking when writing this.
Reply
:iconlikwidoxigen:
likwidoxigen Featured By Owner Oct 30, 2010
I'll get it corrected when I hook up my external but it should be 4096 or if you look at something like the rebel xsi it's 4272 on the long side

Also, no camera has exactly 12mp it's always around there, and they also have to have additional pixels on the edges that are "lost" due to interpolation of the bayer pattern on the sensor itself.
Reply
:iconsounava:
Sounava Featured By Owner Oct 30, 2010   Photographer
DSLRs have 3:2 image ratio and will not have exact 12MP but around it, like 12.3MP for example.

But Four-thirds and other point and shoot cameras have 4:3 image ratio and can have exact 12MP res = 4000x3000 pixels.

Of course when we talk about pixels we are talking about the effective pixels and not the number of pixels present in the sensor.
Reply
:iconlikwidoxigen:
likwidoxigen Featured By Owner Oct 30, 2010
Yup yup.
Reply
:iconlikwidoxigen:
likwidoxigen Featured By Owner Oct 30, 2010
Lol, that's an example of why not to use a formula in a document, because a typo of a 4 instead of a 2.
Reply
Hidden by Owner
Hidden by Owner
:iconjackyramone:
JackyRamone Featured By Owner Oct 1, 2010  Student Photographer
heheh cheers for that, i never knew the maths of the situation, but what's always annoyed me is seeing cameraphones that claim to have between eight and ten megapixel cameras when the tiny lenses physically can't make use of the area provided; they're tiny! more to the point, my SLR has 10 megapixels for christ's sake! why have a phone with the same number??
Reply
:iconb-a88:
b-a88 Featured By Owner Jan 31, 2010
That's very true that when comparing DSLR's with consumer point and shoot models. A lot of point and shoot cameras use megapixels as a sale gimmick. But once you compare same generation DSLR megapixels to DSLR megapixels your getting a better idea of what the difference really is.

But when you said you have to get a camera that is four times the megapixels to get one that is twice as large........ that's just factually incorrect. A three megapixel picture will fit into a twelve megapixel picture four times and that's because it's four times bigger. You can't look at the resolution numbers each individually in a linear manner because at the end of the day it's going to be a squared number that tells the tale.

A 6 megapixel image does fit twice into a 12 megapixel image and therefore a 12 is indeed twice the size of a 6. But when you compare the non squared resolution numbers separately and then directly to a megapixel number of a larger size your going to get confused and come up with the idea that a 12 isn't double the size of a 6 but instead it's double the size of 3.

Another thing that uses pixel resolutions are computer monitors and tv's...... In computer monitors and tv's a lot of people don't look at the resolution though but instead look at the size. What your trying to say is something like this, that 15 is only half the size of a 30 inch monitor or tv.......... now what I suggest is looking at that kind of difference in the real world, you could hardly look at a 19 inch tv or monitor and say that a 37 inch tv/monitor is less than double the size. If you went and looked at them in real life sizes you'd find that a 37 inch is nearly four times the size of a 19 inch.

So what your saying is to disregard completely the area of the images you'll be creating with a camera but instead look at the diagonal size compared to each other. When you do that then yes you'll find that a 3mp resolution is only twice the size of a 12mp when comparing the diagonal measurement but what your failing to see is the power of squared area. There are many other examples that tell the tale of area, like property ownership but I think the monitor comparison works quite well here........
Reply
:iconlikwidoxigen:
likwidoxigen Featured By Owner Feb 12, 2010
There are no factual inaccuracies in my math provided you read it as it is written.

MP= L * W
(4MP) = (2L) x (2W) for equivalent aspect ratios.

To double each of the linear dimensions (Length & Width) you need to quadruple the area. This is why there is an insignificant difference between a 6mp and 8mp image. The linear dimensions are very close.

You apparently conceptualize "size" based on area, which can be proper depending on venue. However, if I have a 4x6 photo and I want to print it at twice the size that would be 8x12 not 5.6x8.49 despite the fact that the 5.6x8.49 has twice the area (MP).

I am in no way mentioning or caring about diagonals which are meaningless in the photo world. Strictly linear dimensions Length and Width. When we do this we find that after we double length and then double the width of a 3MP image we end up with 12MP of total area. Which is what I stated throughout the article. I apologize for any confusion.
Reply
:iconb-a88:
b-a88 Featured By Owner Feb 12, 2010
But that's the thing, 8x12 is four times the size of 4x6, yeah sure the length and width only appear to be two times the size but in fact if you actually put a 4x6 on-top of a 8x12 you'd find that it would fit four times into that.

What I'm getting at is that your saying there is some myth or some sort of scam in megapixel numbers but there just isn't because math doesn't lie, it's incapable of doing such a thing......... the only thing happening is people comparing things that aren't comparable.

I mean I see what your saying but the reason people falsely look at megapixels and print sizes is what's behind that problem to begin with. It's because people are comparing one squared number to two non-squared numbers. Maybe megapixels isn't a good thing to look at when your thinking of print sizes. This might be where a fictional diagonal pixel number would come into play because it'd be on the same sort of level as linear print sizes, rather than comparing an exponential megapixel number to linear print sizes. The only thing people would have to do to take a diagonal into consideration would be to take the square root of the megapixel number, so then if you want to "double" the print size you'd have to get double the diagonal amount of pixels which would be four times as many total pixels. That's why area comes into play because there needs to be four times as many pixels to cover that area and that's why the cost of higher megapixel cameras goes up in exponents over the lower MP's.
Reply
:iconlikwidoxigen:
likwidoxigen Featured By Owner Feb 12, 2010
That's exactly what I said.... 4 times the area is twice the length and width. Because no one cares about the area it's about doubling print sizes, which are what you use with photos. And to double a print size you double the length and width.


Yes the megapixel math is infact a lie and a scam. It is comparing a worthless and unusable measurement (area) to print sizes which are length and width based (you ever order a 24sq in print?). Which is exactly why the 8MP vs 6MP is a worthless comparison because there is virtually no functional difference with regards to printing.
Reply
:iconroxysweetie7:
roxysweetie7 Featured By Owner Jan 29, 2010  Hobbyist Photographer
Men are such horrible creatures, spreading these lies! =p And they say all us girls do is gossip! Very useful info! Thanks for sharing!
Reply
:iconinjato:
Injato Featured By Owner Jan 28, 2010   Photographer
YES! Thanks! Hope you set some people right.. So tired of people yelling about the Nikon D3s only having 12.1 MP. "Isn't it a professional camera?!" Thanks!
Reply
:iconoriontrail:
oriontrail Featured By Owner Oct 22, 2009   Photographer
Wow, nice!

I had 10 megapixel Canon 400D and sold it, and buyed 15 megapixel 500D. :)
Reply
:iconkevenaar:
Kevenaar Featured By Owner Aug 12, 2009  Student Photographer
this is why a digital point and shoot 3mp makes way better photos then a 7 mp camera phone! its the lens and quality of the image sensor! not the amount of megapixels :)

my camera has "only" 10 megapixels but had a great noiseless image sensor (fuji finepix s1500)

grtz
Reply
:iconlikwidoxigen:
likwidoxigen Featured By Owner Aug 29, 2009
You're quite right! There are tons of factors that go into Digital image quality!
Reply
:iconkevenaar:
Kevenaar Featured By Owner Aug 29, 2009  Student Photographer
;)
Reply
:iconpost-sanity:
post-sanity Featured By Owner Jun 18, 2008
I have a two megapixel phone which produces images not as large as my 7mp camera... I dont understand?
Reply
:iconlikwidoxigen:
likwidoxigen Featured By Owner Jun 19, 2008
Give :thumb45967268: a re-read and that should help figure it out.

Cellphone cameras are really just gimmicks and can't be used for serious photography.

The size of the images has nothing to do with quality. A nikon d50 at 6mp will take better pictures every time than a 12mp point and shoot for example.

I don't really see where you're going with this, can you be more specific?
Reply
:iconpost-sanity:
post-sanity Featured By Owner Jun 20, 2008
Oh I see now! I get it.... but a 12mp image... will it be bigger then a 6mp image? (without any re-sizing)
Reply
:iconlikwidoxigen:
likwidoxigen Featured By Owner Jun 20, 2008
Well sure it'll be bigger! but bigger isn't always better!!!

Think of the difference between a 12mp image from a point and shoot and a 6mp slr. The picture from the slr is much higher quality (lower noise, greater dynamic range, sharper lens and sharper sensor). Therefore the "smaller" image can be enlarged much more than the "bigger" image. Does that help make it a bit clearer?

I have a 6mp image that is printed at 20"x30" and it is stunning.
Reply
:iconumbreon17:
umbreon17 Featured By Owner May 9, 2008  Hobbyist Digital Artist
i'm horrible at math, or so it seems D:

if you compair 12 mp with 6 mp you get this right?
[link]

so how is 12mp not twice the size of 6mp?

ohw and my mom want's to buy this camera: Olympus Mju 1010 Midnight Black
do you know if it is good? cuz i can't find anything on the image quality.
Reply
:iconlikwidoxigen:
likwidoxigen Featured By Owner May 9, 2008
Megapixels are a measure of area as in width X height.

A canon rebel had 6MP with measurements 3072 x 2048
The brand new XSI has 12 MP with measurements 4272 x 2848

Area is a number that is very easy to increase with little actual increase in dimensions. They are only adding 1021pixels of width and 800 in height. They are not actually doubling it.

To get truly double the 6mp sensor of the original rebel (double the length and width) you'd need a sensor of 6144 X 4096 which is about 25MP of raw pixel size.

Does that make more sense now?

And I really don't know how that camera actually performs. It is also called the stylus 1010 I checked DPreview.com and coudln't find any sample images. I couldn't even find any after checking flickr. Sorry!
Reply
:iconumbreon17:
umbreon17 Featured By Owner May 9, 2008  Hobbyist Digital Artist
ah thnx it makes sense now. i started with a different definition ^^;

oh i got a link here:
[link]

gives alot of specs too. and i'll go check that site.

thanx for your help ^^
Reply
:iconlikwidoxigen:
likwidoxigen Featured By Owner May 10, 2008
not a problem! Good luck with the camera hunt!

One of my strongest recommendations for a point and shoot is the canon SX100 IS. Give that one a look see too if you'd like.
Reply
:iconumbreon17:
umbreon17 Featured By Owner May 10, 2008  Hobbyist Digital Artist
thnx, i'll give it a good look ^^

*continues camera hunt*
Reply
:iconlikwidoxigen:
likwidoxigen Featured By Owner May 10, 2008
Good luck! and most of all Have Fun!!!
Reply
:iconkajuah:
Kajuah Featured By Owner Apr 8, 2008   Interface Designer
"I got a 3.6MP image printed at 20"x30" and it is absolutely positively gorgeous."


I am very much interested in seeing this picture. Can you upload or cite me to it, please? I assume if you can cite the NYtimes then it wouldn't be a problem in the slightest..
Reply
:iconlikwidoxigen:
likwidoxigen Featured By Owner Apr 9, 2008
Are you looking for the image as the full size jpeg or a picture of the print? Either way it won't give you a sense of it because you'd actually have to see the print.

Regardless, it was taken as a second shooter and so the primary photographer has control of distribution of the image and I'll have to check with them.
Reply
:iconkajuah:
Kajuah Featured By Owner Apr 9, 2008   Interface Designer
I see.

Don't bother.
Reply
:iconkuschelirmel:
kuschelirmel Featured By Owner Mar 28, 2008  Hobbyist Digital Artist
I really like the part where you give your viewer a size comparision through the images - that drives home a point in itself :nod:

what I think should be pointed out a bit more clearly though is that there is a difference between letting professionals handle your image resizizing and trying to blow it up yourself as well as the difference that the original images quality has on the success of blowing a pic up.

I come from the photomanip crowd, and some just don't seem to get that you can't take any pic and enlarge it in Photoshop (there are way better enlargement softwares with better algorithms out there I've been told) by any amount you like and still get a clean image. If the original image is of rather bad quality meaning it's grainy cos the camera itself was crap or over/underexposed you can't blow it up like that, not even a professional could. On the other hand, the same dimensions and resolution, but with a clear image (from a good point and shoot) can certainly be printed bigger than the dimensions would make you think.
Reply
:iconlikwidoxigen:
likwidoxigen Featured By Owner Mar 28, 2008
Yeah, creating the image references was a pain in the butt too, lol.

I wasn't getting into image sizing with that. Image sizing by professionals would be covered in a tutorial on Understanding Print Quality. I agree it needs to be discussed so i'll probably be adding a tutorial with the conspicuous name of "Understanding Print Quality".

Yeah, you really need a good source to start with for manips. For example I have a super high quality 3.6MP picture that I got printed at 20x30 and it enlarged fine and looks totally gorgeous. The real advantage to having more megapixels (like in the 8-10 range) is for cropping room to re-compose the image.

I'm actually working on re-doing this tutorial for my next re-submit and I'll definately include the quality aspect in there as well as the room to crop benefit.

Thanks for the comments they are definately welcomed and super appreciated!
Reply
:iconkuschelirmel:
kuschelirmel Featured By Owner Mar 28, 2008  Hobbyist Digital Artist
:hug: I appreciate your tuts very much - I read them all after catching your DD today ;)
and I do hope you do that print quality tutoral - I'd pimp it for sure :D
Reply
:iconlikwidoxigen:
likwidoxigen Featured By Owner Mar 28, 2008
:hug: That's fantastic! Feel free to always leave ideas/questions/suggestions if you have them! I looove feedback!
Reply
:iconwildefae:
wildefae Featured By Owner Mar 10, 2008  Hobbyist General Artist
I totally agree; I got a Nikon D40 for my birthday and while I was at first upset because I'd asked for a 10mp (it's a 6.8, I think), I was assured by a clerk at Murphy's that really, there isn't much of a difference.

I've seen a lot of pictures since by friends with 10mp cameras and to be honest, I can tell that the quality differences have more to do with our relative experience in photography than our technical cameras. The D40 is amazing and I'd recommend it to anyone over a more expensive but less user-friendly or customizable point-and-shoot 10mp.
Reply
:iconlikwidoxigen:
likwidoxigen Featured By Owner Mar 11, 2008
Heh, I'm glad you agree. I usually never trust clerks at camera or computer stores, they're rarely knowledgeable, but it's nice to find the ones that are pretty good.

I've got a 3.4 or so MP picture printed at 20x30 and it is totally gorgeous. And all the math works perfectly so it's really impossible to argue with. SLR's are on a whole nother level all together.
Reply
Hidden by Owner
Hidden by Owner
Hidden by Owner
Hidden by Owner
Hidden by Owner
Add a Comment:
 
×
Download JPG 792 × 1030

:iconlikwidoxigen: More from likwidoxigen





Details

Submitted on
December 31, 2006
Image Size
250 KB
Resolution
792×1030
Thumb

Stats

Views
6,896
Favourites
72 (who?)
Comments
136
Downloads
241

License

Creative Commons License
Some rights reserved. This work is licensed under a
Creative Commons Attribution-Noncommercial-No Derivative Works 3.0 License.
×