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View Full Version : How many megapixels do you need in a digital camera?



gary_hendricks
12-04-2004, 09:59 AM
One of the most important decisions to make in buying a digital camera is the number of megapixels supported. The number of megapixels determines the quality of your photos. Choose too few for your needs, and your images will suffer. Choose too many, and you might be spending more cash than necessary.

If you have unlimited funds, then, by all means go for that high end 8 megapixel camera. Otherwise, you certainly don't want to waste money on extra megapixels you don't need.

Always try to remember this golden rule: more megapixels isn't always better. If your camera supports more megapixels, then each image will be larger, which in turn means more expensive memory cards and more space used up on your computer's hard drive.

If you have trouble deciding how many megapixels you need (I know I did when I bought my first digital camera), then the guide below will help. Essentially, you need to ascertain what size prints you want to get and what your budget is, before deciding on how many megapixels you want. So here we go:


* 1 megapixel or less: At this resolution, you won't be able to make a high-quality print of your digital photos. You can, however, email the photos or post them on a personal web site. This number of megapixels is typically found on smaller, inexpensive cameras or cameras in combination with other devices (such as cellphones or PDAs). I'd say you'd expect to pay $100 or less for the camera alone.


* 1.1 to 2 megapixels: I'd reckon you need at least a 2 megapixel camera to develop a 4x6 print of decent quality. However, I wouldn't recommend this number of megapixels if you want to take proper family portraits or if you really need a nice-looking print. Expect to pay about $100-150 for cameras in this range.


* 2.1 to 3 megapixels: Pretty good compromise between picture quality and low price for most casual photographers. With this number of megapixels, you can print lovely 4x6 images, decent 5x7s and, depending on the camera, might even get a good 6x9 print. You will pay around $150 to $250.


* 3.1 to 4 megapixels: At this resolution, digital images will make practically photo-lab quality 4x6s, and great 5x7s and 6x9s. You can even print 8x10 in some instances. Price range would hover between $250 to $350 for such cameras.


* 4.1 to 5 megapixels: If you want to capture images for 8x10 printouts, then you need this number of megapixels. Most professional photographers have at least 5 megapixel cameras, usually more. The quality is evident in the photos developed. Cameras in this megapixel range are around $350 to $450.


* 5.1 megapixels and up: These days, you can get 7 or even 8 megapixel cameras from the retail store. While they give wonderful image quality, their price tags will set your head spinning. In this megapixel category, expect to pay $450 and above for a camera.


Well, now you know roughly the number of megapixels you should be shooting for depending on your intended usage and budget for the camera. My general advice is, if you're just a amateur photographer, then don't buy cameras in above 5 megapixels. When you are really serious about digital photography and want to go professional, then consider buying a super high megapixel camera.

jgreve
12-04-2004, 10:25 AM
Just to point out... The number of megapixels doesn't always translate into better overall image quality...granted, pixel count is a good general guide but the actual size of the sensor makes a difference also. A smaller sensor with more information packed into it (like an 8mp sensor on a high end EVF camera) can have more noise and not necessarily "better" resolution than a 6mp DSLR with a larger sensor. That's why most DSLR cameras usually only run about a 6mp sensor (i realize that some do have more, but likely with an increase in chip size)...the extra noise generated by cramming in those extra pixels often negates any advantage gained with any increase in resolution you might see.

gary_hendricks
12-04-2004, 10:55 AM
Hi there

Yes, I do see your point. Thanks for the feedback.

Throughmyeyes
12-04-2004, 01:25 PM
Megapixel count helps out if you want to print large images, I can do great 13x19" prints from my 8Mp, however I also have seen some great 11x14" prints taken with a 2Mp, important thing is to watch the histogram to be sure you are filling as many pixels as possible with out overexposure.

Also higher Mp cams are coming down in price but the larger the Mp the larger the storage card, imho I would recommend at least a 4Mp, only because it happens to be "middle of the road" so to speak :o

sfaust
12-04-2004, 02:12 PM
jgreve got what I feel is the most important point. Its the sensor size and quality that make the biggest difference. For example, take a professional level digital SLR with interchangable lenses, 6MP, and quality lenses, and compare it to a 8MP consumer fixed lens SLR, and the image from the 6MP camera will be better in almost all occasions. This is because of the sensor they put in the professional cameras vs the smaller sensors in the consumer camera. Thats also a large part of the $2K price difference!

As case in point, take the 8MP consumer camera and the 6MP prof camera out for a trip night shooting. If the consumer even has a speed over ISO800, its not going to be very pretty. But on the prof camera, the ISO800 is going to look very good in comparison. And it probably even has a very usable ISO1600 setting where the consumer cameras usually don't even have and ISO1600, and if it does, it typically looks pretty bad and unsuable. This is due to the sensor quality, and is irrespective of the MP size. Its on of the tests I do on any camera I am considering purchasing is to test its upper ISO limits.

My little Sony P100 pocket 5.1MP camera looks awesome at ISO100. Put it up to ISO400, and it looks llike the image was made with grains of salt. Yet the ISO1600 on my S2 pro does show some grain, but it looks like film grain, which is quite acceptable. At ISO800, its pretty good all around, and at the same ISO400 where the P100 totally falls about, it looks about as good as the P100 at ISO100, which is awesome.

So think sensor size and quality together with optical lens quality as the things to watch for in image quality, and MP size as the item that determines the maximum size of quality prints you can make. A bad sensor at 22Mp will make awesomely big bad quality prints. A quality sensor at a smaller MP size will make awesome quality prints but in a smaller size. Balancing the two, and bringing into your budget range I think is the key.