Kinda depends, generally in my experience the size of a jpeg high res image directly from, say a canon t2i, is between 5.5 and 11mb, some as much as 16mb. An estimate therefore would be approximately 2979, 1489, and 1024 pics respectively. This however is only an estimate as each picture has different information which takes up more or less space than the previous picture even on the same device. Aditionally, it's unlikely that you would be using or keeping pictures in raw, but if you are, expect considerably less than that, on average canon raw files are around twice the size and generally save jpeg as well for menu images. So it would put that average number at around 750 or so pics, but most likely less.
1 Gigabyte (Gb) is 1 Trillion bytes and a Megabyte (Mb) is 1 Million bytes. So if you did a quick calculation of 8 Trillion (8Gb) divided by 18 million (18Mb), the answer would be 444.444444 Mb (I used Google because most calculators don't have that many digits).
BUT - and here's where it gets complicated - Megabytes are not Megapixels! In fact, depending on the quality setting on your camera, most digital photos have a FILE SIZE of more than 1 Mb. For example, the file for an 18 Megapixel photo might actually be anything from around 3Mb up to 30Mb, depending on the quality setting on the camera.
SO...if you have a 8Gb memory card, you could put as many as 2730 photos (at 3Mb each) or as few as 273 photos (at 30Mb each). At an average file size of 10Mb per photo, which represents a very good quality photo - suitable for printing at the normal size or even for making enlargements - your 8Gb card could hold about 800 photos.
about 2000 pictures.
If you set your camera for 1mb each photo, it will save 300 photos. It depends on how you set your camera.
A rough estimate is 125 photos. You will probably get a few more because the camera compresses the photos to save memory.
The number of photos that can be held depends entirely upon what quality you wish to shoot the pictures at. A 5 megapixel camera, at maximum resolution, probably won't hold many photos. (25-30) As the resolution increases, the number of photos that can be held decreases exponentially. At a lower quality (say 640 by 480) you can hold between 1000 and 3000 photos on a 256 mb camera, depending upon the compression.
About 6-8 photos.
You can figure it out by dividing 2GB (2 billion) by 12MP (12 million) which works out to roughly 167 photos. The camera compresses the photo data, so you will actually get more photos (something like 200 photos I would guess)
A 128mb memory car would hold about 70 4mp photos. But it depends how many mp (mega pixels) you camera has. Hope this helps you dtracer (i would be grateful for any points given)
Depends on the resolution you have the camera set at and the size memory card. 40 MB will hold aound 26 photos at best resolution on a 3.0 MP camera.
That depends entirely on the camera, compression method (if any) and the individual photos involved. By my calculations and assuming a 10mp camera shooting RAW, the 128GB card would be able to take APPROX 8544 images.
= How many photos can 19 MB hold at 12 megapixels? =
It is recommended with a camera that is this sharp you have a minimum of a 1 gigabyte memory card. On this card you can fit approximately 56 pictures depending on the lighting and subject involved.
you don't need a card to take photos but is optional, without a SD card 300 photos can be taken, with a 1gb SD card i can take 3,000.