PDA

View Full Version : How many megapixels



Lollen
01-11-2010, 1:30pm
Hi all,

How many megapixels is your camera, and how does it affect the quality of your photos?

Are megapixels important to quality shots??

Thanks
Lauren =)

arthurking83
01-11-2010, 4:41pm
Hi all,

How many megapixels is your camera, and how does it affect the quality of your photos?

affect?.. in what way? There are many variables, effects and issues in how the number of pixels in a camera can have an impact on photos.
Too many(for a given sized sensor), can produce more noise, ultimately capture less light, cause diffraction... show up imperfections in lenses previously thought to be perfect.. etc, etc.


Are megapixels important to quality shots??

Thanks
Lauren =)

The way I see it, is that the ONLY reason you'd want more pixels is for reproducing larger displays of the image, on any medium.
Two common outcomes of this reasoning is larger prints.. where, as a rough example(and not taking the figures as exact and implicit facts) say you have a 6Mp camera, and that realistically allows you to print a 1meter wide image, once the file has been finalised. You'd then assume that a 12Mp camera may allow you to then print a 2m wide print.. but it's not so simple!
A 6mp camera may have 3000 pixels across the sensor, whereas a 12Mp camera may only be 4800 pixels across. For the same era of technology, the 6Mp cameras pixels can (or should!!) be able to allow the capture of higher quality light. The smaller pixels in the 12Mp camera will struggle to capture the same quality of light.
With good software, you can stretch those larger pixels(in the 6Mp camera) using a process called interpolation, which can render the effective pixel count as much as 50% higher.. but lets deal with a more conservative figure of 33% instead(and easily achieved from what I've read about and seen.
So with your standard 6Mp camera, you can print up to 1 meter. Common wisdom would dictate that the larger 4800pixel wide 12Mp camera should then be able to print at up to 1.6 meters wide.. being 60% wider(the height ration is assumed to stay the same).
If you can interpolate the original 6Mp camera to 33% more with absolutely no loss in quality, then you can effectively print the 6Mp camera's images to 1.33 meters.
We're talking very large prints here now!!
The smaller pixels are much harder to effectively work with compared to the larger sized pixels(remember for the same level of technology!!)
The higher quality of the larger pixels is more of an advantage in many cases of say low light, or pushing the quality of the captured light.
Where the higher number of smaller pixels comes to the fore is in displaying more detail or allowing one to crop the image more heavily to display more detail.

Your goal in photography should dictate why you want more pixels or not.

The main method of judging the quality of images by a dedicated group of photography enthusiasts is not about the actual quality of the pixels in the image. It's more about the image's personal properties, such as how the photographer composed the scene, the exposure levels, the artistic expression, the type of lens used is more important to the 'quality of the shot' than the what camera was used. It's the operator's initial ability that makes the most difference tho.

For me.. given the choice of a 5yo 4Mp DSLR, over tomorrow's high tech, 16Mp super slick, current technology compact camera(with all the fruit).. I'd take the lower 4 MEGA pixel camera any day! :th3:

Lollen
01-11-2010, 5:06pm
Uhm ok...?

Rattus79
01-11-2010, 5:14pm
All of that said, I can visibly see the difference betweeen my *ist DS (6mp CCD pentax) and my K10d (10.2 CCD Sensor) when shot side by side using the same lens. I did the test, and the K10's images are far superior.

Choosing a camera is more a case of what type of photography versus the budget you have.
It's the old addage of better body vs better glass.

arthurking83
01-11-2010, 5:47pm
confusing huh, Lollen! :D

Greg! I'm assuming that the *ist DS is older technology than the K10.

To understand what I'm talking about, see Canon's recent semi pro compact series called the G11. This particular series of camera from when it started has had a steady increase of pixel count.. all the way up to the penultimate incarnation(G10) where it eventually ended up with something like 15Mp (or more??). Life started out fine for the G2 at 4Mp(and remember these things have very small sensors compared to a DSLR!) and ended up at 14.7Mp with the G10. But Canon got smart and decided that the newer better G11 only needs 10Mega pixels. Reason is that as pixels become smaller, they struggle to produce better results. But that's when you maintain the same level of science behind the camera's underlying technology.
Increased technology levels in the camera.. digital to analogue conversion, more powerful CPU's and more of them(Nikon D3 series) and so forth. They allow the manufacturer to extract more from each pixel, so that they can then squash more of them onto the small sensor chip.

More pixels are handy to have.. as you can have more to play with.. but that doesn't necessarily give you higher quality images.
In Canon terms.. I'd rather have a 5D with its (what?.. 12 or 14Mp) rather than the 7D with it's 18Mp.. and again, I'd prefer the 5D mk II with it's 19Mp over both as the underlying technology in the camera will always give either the same quality or higher images in the end.(choose your lens wisely tho!). With Nikon.. I'd rather have the 12MP of the D3s over the 25MP of the D3x. I'd also prefer the 6MP crop aspect of the D700 over the 12MP of the D300 any day, but I like the deeper DOF that the D300 allows in being an APS-C camera for most of my shooting. This is for my purposes tho!!
You haven't specified your reasons for the question.
Someone that specifically shoots small birds from far away, or macros of infinitely small bugs, or that routinely prints images like really really big, will always want more pixels.

The answer to your question of are megapixels are important to quality shots therefore becomes both yes and no. It'll depend on the requirement of the shoot.
(I'm assuming that the question is actually asking .. are MORE megapixels are important to quality shots)

ZedEx
01-11-2010, 9:10pm
I point I try to make to all my customers is thus: In this day and age, pixels do not matter for 99% of camera buyers out there. I have people snob their noses at 10mp cameras now, and some even turn their noses at 12mp cameras!
When people were comparing 6mp to 10mp, that was quite a jump (almost twice as many pixels). But from 10-12 and from 12-14 the increase in resolution is minescule. Unless camera manufacturers are also increasing the resolving power of the lenses attached to compact cameras, then it is 100% marketing hype.
In SLR's, you won't notice much (if any) difference between 10mp and 12mp. By any means, 10mp can be interpolated to 12mp no quetsions asked. To 'out resolve' say a 12mp sensor, you're going to need some exceptionally good lenses. So what I mean here is that a Canon 7D (18mp) with a kit lens off say a 350D (8mp) may not be any clearer. Sure, there are more than twice as many pixels on the sensor, but if the lens can't actually physically be that sharp, then there is no point. I have done 30x40inch prints from a 10mp dSLR with an ok-ish lens which to me was just pushing the limits. Now, with better lenses, I could achieved something bigger still. Ask yourself: how often do you print THAT big?

Now more than ever, consumers should consider the implications of investing in better lenses rather than chucking out 'yesterdays technology' in favor of a new body.

Tannin
01-11-2010, 9:11pm
Hi Lollen,

Congratulations!

If you want to be given a vast amount of interesting information about pixel size and image quality, you could not do better than ask Arthur. Asking Arthur about megapixels is like asking Billy Graham about Islam and Christianity, or asking Lenin about the merits of communism, or asking Torquemada about the rules of evidence and the role of human rights in judicial inquiry - you will always get an opinion, you will get a lot of interesting information, and you certainly won't ever be bored .... but one or two people might disagree with the information provided!

How important is the megapixel count? Is more better? Or is this a case of less is more?

The answer - and too hell with what Uncle Arthur says, I'm giving you the real answer now - is a very firm, very clear "it depends". Remember that - it depends - it's the answer to nearly every photographic question. And the reason this is so is that nearly every photographic decision is a trade-off. Which is better, fast shutter speed or low ISO? It depends. Would you rather have a fast , heavy lens or a cheap light lens? It depends. What is the best brand of camera? It depends. How many megapixels should I have? It depends.

Tell us what you have, what you do, and what alternatives you are thinking about. Post that here and someone will be along to make some recommendations and provide you with advice. Will that advice be any good? Well, it depends!

kiwi
01-11-2010, 9:17pm
It depends.......on how much you crop.

ricktas
01-11-2010, 9:23pm
MP are only one part of an entire equation. Yes they are important, but not as important as the advertising would make you believe. They marketers saw it as a way to impress the public for quite a few years and it worked, so they repeated the formula. Offer more MP and the public will lap it up.

So as AK and Tannin both say, it depends. MP are important, but so are all the other components..right lens for the job, good quality lens etc. In the end choosing the wrong shutter speed and getting a blurry photo, it doesnt matter if you shoot with a 5MP or 21MP camera, it is still going to be blurry.

Kym
01-11-2010, 9:30pm
KISS...
1. Today all current digital camera's have enough MP for 99.9% of photographers needs. (in fact more than enough)
2. The quality of lenses is a much bigger factor in getting great images (although even kits lenses work well within their limits)

Re: 1. ... If someone want to give me a 40.1MP 645D - I'll quite happily use it ;) :D

hoffy
01-11-2010, 9:33pm
MP does not mean Mega Pixels. MP means Marketing Ploy!

farmer_rob
01-11-2010, 11:18pm
I bet Lauren wasn't expecting all this for a simple question!

I'm quite intrigued by the MP (and implicitly the pixel density) issue. Lets make 2 assumptions: No Cropping - so you are comparing apples with apples; and the lens is of sufficient quality to make no difference regardless of sensor (big assumption, but it only really fails at d3x sensor sizes).

Most people here resize their images to display on the web (or their monitor) - either explicitly or implicitly (hands up those with a monitor > 3872 x 2592 pixels: D40x native size, 10MP). Very few people print - and even then it is mainly for the good/great shot, or personal purposes. I get the light gathering bit of larger pixels (simpler CMOS techniques for lower crosstalk and noise) which makes quality high ISO easier to achieve on FX cameras. But my key stumbling block is:
a) take a picture in good light at ISO 100, RAW
b) process to your heart's content and save as high quality jpeg.
c) resize it to 1024 pixels on the longer edge
d) Regardless of camera, I bet you can't tell if it came from a d3x (25MP) or a d40(6MP) - or the canon equivalents.

I'd say in this day and age, 10MP for a DSLR less than 2 years old will give you a sufficiently high quality picture for all non-large-print usages *unless* you need low light capabilities (ISO 800+). (And I don't accept AK's argument that he *needs* an FX camera to fix his DOF fetishes issues.)

BTW larger prints have different issues: viewing distance is all important. Have a look at a billboard really close and tell me that that they really get that fine grained detail when you are 30cm away - or what MP and frame format they shot at.

Oh, and bird photography is different (before Tannin pecks my head off.)