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 Standard Test Scene |
To provide an impression of each image size / quality combination you will find a sample of each below.
(2272 x 1712 JPEG 5:1)
(2272 x 1712 JPEG 10:1)
(1136 x 856 JPEG 15:1) (1136
x 856 JPEG 30:1) Images below are cropped 240 x 100 area of the image magnified
200% (nearest neighbour).
| 2272
x 1712 |
 2,618 KB |
| 2272
x 1712 |
 1,268 KB |
| 1136
x 856 |
 591 KB |
| 1136
x 856 |
 275 KB |
I was VERY surprised to see the amount of JPEG artifacts visible in the
and
images. Take the 1136 x 856
image as an example, it weighs in at 591 KB. At this JPEG file size and
resolution we would expect a very high quality image without any artifacts,
yet artifacts are clearly visible. As an experiment I took one of the
2272 x 1712 images, half sized it and saved it as a JPEG from Photoshop
(quality 9). This new test JPEG was only 342 KB in size and yet
exhibits almost no artifacts.
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| 1136 x 856, 591 KB JPEG Created by the HP 812 |
1136 x 856, 342 KB JPEG Created by Photoshop (from an 812 image) |
What does this mean? In simple terms it means that you are not getting "good storage value". You are storing (on your limited size SD card) a large file size image which doesn't deliver clean artifact free image quality. Although artifacts are not visible in the 2272 x 1712 images I'm sure that what we have discovered here means that they could have been smaller (file size) and still delivered the same JPEG quality.
