Do You Need to Upgrade Your Digital Camera?
New and improved digital cameras are continually coming on to the market, so from time to time, you will want to decide whether it is time to upgrade your camera. The notes that follow, summarise my experience with upgrading digital cameras, with particular reference to the resolution of the images captured and the size of good quality prints that can be obtained from cameras with different megapixel ratings. Please read also this page in conjunction with these notes, it deals with the conditions that are necessary for obtaining high quality large prints from your digital camera. In addition, I found the comments made in this July 2009 Dyxum forum discussion to be very interesting. This discussion is titled: "Sony A900: Do you really need 24.6 megapixels?"
I started off in the year 2000 with a 3 megapixel (mp) digital camera, which produced image dimensions of 2048 pixels x 1536 pixels (4:3 aspect ratio). I was able to make excellent quality prints up to a width of 10.24 inches at 200 pixels per inch (ppi) (2048/200 = 10.24). In particular, photographs of people and flowers etc. taken at close distances were very good, but, to be honest, the details of buildings, trees etc. in distant landscapes were a little “blotchy” when looked at from very close range, but quite acceptable when viewed from a metre or more away. With some high quality 3 mp images, I was able to make reasonable quality A3 sized prints (16.5 inches x 11.7 inches).
So, when 5 mp cameras came on to the market, I hesitated about upgrading, but I was impressed with the additional fine detail captured by these cameras. My 5 mp camera produced image dimensions of 2592 pixels x 1944 pixels (4:3 aspect ratio), so I was able to make an excellent quality print with a width of 12.96 inches at 200 ppi. Therefore, in comparison with images from my 3 mp camera, the print width at 200 ppi had increased by 26.6% from 10.24 inches to 12.96 inches. With some high quality 5 mp images, I was able to make reasonable quality A3 + sized prints (19 inches x 13 inches).
When I had the opportunity to upgrade to the 10.3 mp Sony R1 camera, which has a large 21.5 mm x 14.4 mm sensor and produces image sizes of 3888 x 2592 pixels (3:2 aspect ratio), I was pleased to see that, particularly with distant objects in landscape pictures, there was a great deal more fine detail captured by the Sony R1, than was captured by the 5 mp camera. With the Sony R1, this allowed me to make an excellent quality print with a width of 19.44 inches at 200 ppi. So, in comparison with images from my 5 mp camera, the print width at 200 ppi had increased by 50% from 12.96 inches to 19.44 inches. With some high quality 10 mp images, I was able to make reasonable quality A2 sized prints (23.4 inches x 16.5 inches).
In early 2009, I purchased the full frame 24.6 mp Sony Alpha 900 camera. The dimensions of an A900 image are 6048 pixels x 4032 pixels (3:2 aspect ratio), which allows me to make an excellent quality print with a width of 30.24 inches at 200 ppi. So, in comparison with images from my 10.3 mp camera, the print width at 200 ppi has increased by 55.6% from 19.44 inches to 30.24 inches.
The resolving power of the Sony A900 is quite amazing, and the fine detail captured in images in distant landscapes is noticeably better than that captured by the Sony R1. Click here to see photographs that demonstrate the amazing resolution that can be captured in Sony A900 images. I have found that, with top quality A900 images, I can make a very good quality print that has a width of 40.3 inches when printed at 150 ppi.
But, if you do not wish to enlarge your prints beyond, say, 19 inches - 23 inches, you may question the need to upgrade from a good 10 mp or 12 mp camera, to a 24 mp camera. However, one advantage of a 24 mp camera, is that you can crop out quite a large area of an image and still make a very good large print from the smaller sized image. For example, click here to see a "portrait" of a cotton top tamarin monkey that has been cropped from the much larger Sony A900 image seen on that page.
In addition, click here to see a nice close-up image of a tiger, that was cropped from a Sony A900 image that originally had dimensions of 6048 pixels x 4032 pixels. The crop has a file size of only 3024 pixels x 2016 pixels, which is half the width and half the height of the original image. However, if this image is printed at 150 pixels per inch (ppi), it will still give a good quality print with a size of 20.16 inches x 13.44 inches. Another example is when you have taken a photograph of a group of, say six people. With an image from the Sony A900, it may be possible to make a good sized print of, say, just one of the people from the group.
Note that, if a Sony A900 image is captured using, say, a 24 mm wide angle lense, it may be possible to crop out the top and bottom quarters of an image, thus leaving in the middle of the picture, only the distant landscape. Although this may reduce the dimensions of the image to, say, 6048 pixels x 2016 pixels, it may still give an excellent quality large panoramic print, of approximately 30 inches x 10 inches when printed at 200 ppi.
It is mentioned here that an image from a small compact camera does not capture as much fine detail as an image from a digital single lens reflex camera ( DSLR), because the DSLR has a larger sensor. The larger sensor of a DSLR enables each pixel to be larger than is possible with a smaller compact camera. Therefore, the images from a 12 megapixel DSLR will contain more fine detail than would be the case with the images from a 12 megapixel small compact camera. Click here to read more about the basics of digital camera pixels.
Conclusions
Perhaps the most significant factor that motivated me to upgrade to the cameras referred to above, was the increased amount of fine detail that could be captured as the number of megapixels was increased. For example, there is a huge increase in the amount of fine detail that can be captured by a 24 mp camera, compared with that of, say, a 3 mp camera. Although it may be possible to enhance / upscale the images of a 3 mp camera so that relatively large prints can be made, the original image probably never recorded a lot of the fine detail that can be seen in an equivalent 24 mp image. This applies, in particular, to detail that can be seen in landscapes, where the scene recorded is located several kilometres away from the camera.
For example, in the second image on this page you can see individual people and can read the name on the boat, even though the camera was located on a hilltop some 4-5 kilometres away. In my opinion, it is probable that a 3 mp camera could not have recorded such fine detail. However, a comparison with a good quality 12 mp DSLR camera, may show that a lot of this fine detail was captured, but perhaps not as clearly as was possible with the 24 mp camera. Note that an image from a small compact camera does not capture as much fine detail as an image from a digital single lens reflex camera ( DSLR), because the DSLR has a larger sensor.
The maximum print sizes that you wish to make, are also a significant factor in deciding whether you need to upgrade your digital camera. For example, if you want to make quality 30-inch prints at a good resolution (such as 200 ppi), then a 24 mp camera may be very useful. In comparison with a 10 mp camera, the Sony A900 will permit you to make prints that are nearly 56% larger (6048 / 3888), given the same 200 ppi resolution. If you are thinking of upgrading from a 12 mp camera, such as the Sony A700 (which produces images with a dimension of 4272 pixels x 2848 pixels), then the Sony A900 will permit you to make prints that are nearly 42% larger (6048 / 4272), given the same 200 ppi resolution. In addition, if you enjoy working with an imaging program and wish to make large prints from only a small part of an image, then a 24 mp camera may be very useful.
In practice, the decision on whether or not to upgrade a digital camera is based on several factors, other than just increased resolution and larger print sizes. The cost of the upgrade, relative to the benefits obtained, will be considered closely by people who make their living from professional photography. To get the maximum benefit from a 24 mp camera, you need to buy top quality lenses, and these may cost more than the camera body itself.
Click here to read a more detailed discussion about the conditions necessary for obtaining high quality large prints from your digital camera.
Click here to go to an article titled "Advantages and disadvantages of cropping images to gain extra reach".
Click
here to read an article about the crop factor, and the
mathematical relationships between pixel density and pixel size (based on
both linear and area measurements).
Click here to see some pictures that demonstrate the amazing amount of detail in images taken by
the Sony A900.