File Size Question

[WendyB]

I have a Canon S2 IS - new to me - it is a 5 megapixel, 12x zoom camera. Aside from a few - ok several - operator errors in photography, I'm very happy with the camera. However, I'm very curious about file size. When I put the photos on my computer and see them in file name/detail list, it shows the file size and some are over 2000 kbs, some are around 400 kbs and some are at any point in between. What makes the file size go from 400 kbs in one shot, and 2851 kbs in another? Does it have to do with the zooming? If I zoom alot, does it make a larger file size? I suppose this is not crucial information, but I'm curious. Is the file size an option that I'm choosing as I make menu selections for a specific photo? Any info will be much appreciated. Thanks all. Wendy

[koppelman]

This post from Wendy about 2 years ago never received any replies.

I find myself with the same question. Setting file size to large should, according to the manual, generate images with 2592x1944 pixels. That is the equivalent of 5 Megapixels. I would love to generate files that large. The largest file that I have generated using this setting is 3 megapixels, and in fact I do not consistently generate that size of a file.

This issue is of relevance to me as I would like have my photos occupy the entire viewing area on a 32 inch computer monitor. The apple cinema screen would require an image to have 4 megapixels in order to occupy the entire viewing area of the monitor.

Thanks
koppelman

[hokeyguy]

This post from Wendy about 2 years ago never received any replies.

I find myself with the same question. Setting file size to large should, according to the manual, generate images with 2592x1944 pixels. That is the equivalent of 5 Megapixels. I would love to generate files that large. The largest file that I have generated using this setting is 3 megapixels, and in fact I do not consistently generate that size of a file.

This issue is of relevance to me as I would like have my photos occupy the entire viewing area on a 32 inch computer monitor. The apple cinema screen would require an image to have 4 megapixels in order to occupy the entire viewing area of the monitor.

Thanks
koppelman

I set my S3 to "Large" and "Superfine" which gives me a resolution of 2816x2112. The actual file size varies depending on the data and the compression. The image is always 2816x2112 pixels though.

[jonalta]

Yep. Setting the S3 (or S2) to "Large" then "Superfine" would render the maximum resolution.

[griptape]

Pictures can also vary greatly in file size depending on the subject. Take a picture that's nothing but white, or nothing but black and it will be a very small file size. Take something with tons of different colors and contrasts and you'll end up with a much larger file.

[Visual Reality]

The maximum resolution on a 30" LCD monitor is 2560x1600, for a TV with 1080p it is 1920x1080p. A 4-5mp camera will be needed for the monitor and 2-2.5mp camera would be needed for the TV. If its a 720p set, you only need 1366x768 size images which is only just over 1mp.

[truflip]

has somebody mentioned that the more colours in the picture, the larger the file? Also images with darker shades tend to be larger as well.

[griptape]

Pictures can also vary greatly in file size depending on the subject. Take a picture that's nothing but white, or nothing but black and it will be a very small file size. Take something with tons of different colors and contrasts and you'll end up with a much larger file.

^Yep. A couple posts above you.

[koppelman]

The maximum resolution on a 30" LCD monitor is 2560x1600, for a TV with 1080p it is 1920x1080p. A 4-5mp camera will be needed for the monitor and 2-2.5mp camera would be needed for the TV.

Thanks for your replies!
May I submit a follow up question?
You mention that a 4-5 mp camera will be needed for a 30 inch monitor. However if that 4-5 mp camera takes a photograph that has a file size of 2.3 megapixels, isn't it true that this image will not fill the entire screen of a 30 inch monitor?

Many thanks
koppelman

[griptape]

^If you change the megapixels, it's no longer a 4-5 megapixel camera. It becomes a 2 megapixel camera, and no, a 2 megapixel image will not fill that resolution.

[Visual Reality]

That's right, if you take a smaller picture it won't fill the whole screen.

[David Metsky]

File size does not equal image size. All these cameras are doing JPG compression, which will reduce the file size without changing the dimensions of the images. Unless you are shooting RAW, the final file size isn't directly representative of the image size.

[koppelman]

Thanks once again for your patience with me. I now understand my confusion. I have been equating megapixels with megabytes.

When I saw that my photos had a file size of 2.5 MB, my brain equated that to 2.5 megapixels. Now it makes sense to me.

koppelman