The Level 10 setting for JPEG quality produces the highest image quality level for
in-camera JPEGs, while Level 1 yields the highest compression ratio. The higher the
compression ratio, the greater the potential for image quality degradation, and vice
versa. Therefore, when preservation of fine detail is important, we recommend shooting
RAW files or high-quality JPEGs. The camera's default setting for JPEG quality is more
than adequate for most applications, but we suggest that you try some of the other
settings to determine your "comfort level."
Another aspect of selecting JPEG quality settings is their effect on the maximum number
of shots that can be taken in a continuous burst. With the Mark II cameras in particular,
buffer performance improves substantially at lower JPEG quality settings due to smaller
file sizes.
In-Camera Sharpness,
EOS-1 class digital SLRs have additional image quality settings including sharpness,
Contrast, Saturation &
contrast, saturation and color tone, which can be applied to all images. In the case of
Color Tone Control
RAW files, these settings can be overridden in post-processing. However, it is very
important to understand that sharpness settings in particular can have a significant
effect on the appearance of in-camera JPEGs, i.e., images that are shot as JPEGs in the
camera as opposed to RAW files that have been converted to JPEGs in your computer.
Before getting into a detailed discussion of sharpening in-camera or on a computer, it's
important to realize that pictures taken on overcast days or taken indoors with only
natural light look softer than pictures taken on sunny days or indoors with direct flash.
Why? Because overcast day/indoor natural light pictures have less contrast than the
sunny day/direct flash pictures, and pictures with less contrast look softer than
pictures with more contrast. Knowing that, the contrast of a somewhat softer image can
be boosted in-camera or in an image-editing program, giving the appearance of a
sharper picture.
Speaking of soft images, lens flare can cause even a picture taken on a sunny day to
look soft. Another cause of an apparently soft image (or more commonly a soft area of a
picture in this case) is over-saturation. When an image or image area is over-saturated,
it loses detail and looks soft. This can often be corrected by reducing the saturation
in-camera or in an image-editing program.
Sharpness: To satisfy a wide range of photographers, EOS Digital SLRs vary significantly
in terms of range and default settings for sharpness, which is more correctly referred to
as in-camera sharpening. Entry-level and advanced amateur models such as the EOS
Digital Rebel, 10D and 20D use a 5-step sharpness scale from -2 to +2, with default
settings typically at 0 (mid-scale) or +1. This is a noticeably higher level of in-camera
sharpening than the default settings for EOS-1 class Digital SLRs, and may cause some
concern for photographers who use both cameras. On the other hand, the default
setting for sharpness level on EOS-1 class Digital SLRs is 0 on a scale from 0 to 5. This
lack of in-camera sharpening was intentionally chosen by Canon to preserve as much
III. IMAGE QUALITY SETTINGS
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