what exactly is a megapixel?

[SonicIce]

?

 

[JackBurton]

One million pixels.

 

[RaynorWolfcastle]

mega is a prefix for 1 million
1 megapixel = 1 million pixels, it usually refers to the number of pixels a camera's sensor can record but it can be used in any context.

 

[dullard]

Just curious, is it

A) 1000x1000 pixels = 1,000,000 pixels

or

B) 1024x1024 pixels = 1,048,576 pixels?

 

[RaynorWolfcastle]

Originally posted by: dullard
Just curious, is it
A) 1000x1000 pixels = 1,000,000 pixels
or
B) 1024x1024 pixels = 1,048,576 pixels?

Technically mega is a base-10 prefix, and that is usually used for any physical measurements, eg hard drives. The binary prefix is technically mebi but that's never used for historical reasons and that's where the confusion is from.

I'd be willing to bet that camera manufacturers use the base-10 definition.

 

[dullard]

Originally posted by: RaynorWolfcastle
Technically mega is a base-10 prefix, and that is usually used for any physical measurements, eg hard drives. The binary prefix is technically mebi but that's never used for historical reasons and that's where the confusion is from.

I'd be willing to bet that camera manufacturers use the base-10 definition.

I know the difference quite well. I like to chime in every once in a while in those "My 40 GB HD only says 37 GB" threads. They always end in a flame war with people arguing that HD manufacturers are the only computer hardware companies using the true mega (base 10) definition. I never thought of cameras, so maybe this is another thing to throw in their face (or maybe it is another thing for them to throw in my face if cameras use base 2 mebi).

 

[Kingofcomputer]

zip disk, cd-rom/r/rw, dvd-rom/r/rw, flash memory also use base 10.
storage media mostly use base 10.