These days cameras come with MegaPixels as high as 20 to 30 MP but like other cameras, you can use them in a wide range of image resolution. In my opinion, setting camera to a proper resolution value is a very important setting. Let us quickly look at the costs and benefits of using too high resolution setting.
Like many things in modern life, we believe in 'bigger the better'. So many of us, without putting many thoughts into it, use the camera in the highest resolution it offers. However we need to have a reason for choosing a 20MP resolution for a photo that you are never going to print. Most computer monitors CAN'T display more than 4 Mega-Pixels. Your smart 1080p HD-TV can show only 2 Mega-Pixels. How to choose an optimum resolution setting on your camera? Think about the biggest photo or poster you have printed so far or you see yourself printing. Most of us never print beyond 4x6 inch prints or maybe 8x10 inch prints once in a while. If that is true, a 20MP photo or a 4MP photo when printed as a 4x6 inch print or 8x10 inch print would not bring you any more sharpness or clarity in the photos printed at Costco, Shutterfly, or photo labs in most stores like Walgreens, CVS, Target, Walmart etc. Here is the resolution typically required for various prints or for viewing.
Print Size in inches | Pixels required for printing/viewing | MegaPixels in image (Rounded to nearest full number)) |
4x6 | 800x1200 | 1MP |
8x10 | 1600x2000 (@200 dpi printing (most stores print at 150 dpi) | 3MP |
12x18 | 1380x2070 (from Costco.com website) | 3MP |
16x20 Poster print | 1840x2300 (from Costco.com website) | 4MP |
Viewing a photo on a 1080p HDTV | 1920x1080 pixels | 2MP |
Viewing photos on a 22" LED monitor | 1920x1080 pixels | 2MP |
Viewing photos on a 30" LED monitor | 2560x1600 pixels | 4MP |
For many situations, like photos in some party, if you know that you are not going to print any photo in a size bigger than 8x10 inch, you can save space on your memory card, on your computer, or conserve bandwidth while emailing photos or uploading them on Facebook by setting MP to 6 to 8MP instead of using camera's maximum resolution of 16 or 20 MP. Costs of taking unnecessarily large resolution photos:
Potential Benefits of Higher Resolution photos:
1. Using High Resolution when you can't zoom in: If you don't have
a zoom lens, a higher resolution photo can come handy. If you want
to take a photo of something specific but you can't zoom in, set
your camera to the maximum resolution it supports and then crop
out the unnecessary things from the photo. This way what you wanted
in the photo is still in high resolution. So in short, a high resolution
can sometimes be useful as a zoom lens.
2. Avoid regrets: If you took a photo that came out too good and
you simply loved it. Say you want to make a life size portrait of
your kid's photo. In such situation, sometimes it is too later if
you took photo in only 6MP mode. You would regret why you didn't
take photo in highest resolution your camera offered! So it is a
choice to make. You can take a rational approach or try to cover
all possibilities and decide to take each photo in 20MP. Would you
take 10000 20MP photos to avoid one photo down the road that really
would have benefitted from 20MP!
In my opinion, if you are probably not going to print photos in print size bigger than 12x18, but want to keep options open, take photos in 10MP mode. Or depending on situation, keep changing resolution setting on your camera. When taking photos for selling items on eBay or Craigslist, I set my camera to 2MP mode. Taking photos of kids at my son's birthday party or during his soccer game, I would set camera to 6MP. For family photos and photos of friends, I set it to 10MP. When I come across beautiful landscapes or am taking portraits, I set camera to the maximum resolution it offers.