7D softness - conclusions

Started Dec 5, 2010 | Discussions thread
Shop cameras & lenses ▾
ForumParentFirstPreviousNextNext unread
Flat view
Michel Savage
Contributing MemberPosts: 746Gear list
7D softness - conclusions
Dec 5, 2010

Following two recent threads on 7D softness, here are some conclusions I arrived at.

1. The perception of softness is caused by the resolution. The higher the resolution, the stronger this impression of softness.

2. The resolution of a high resolution picture is higher than the resolution of most computer screens. Therefore, the only true method to evaluate sharpness, is via print.

3. From all the posts on the subject and from my own comparisons, it appears clear that there are variations in RAW sharpness from one 7D unit to the other. These variations may be caused by faulty quality control, misadjustment caused by handling and shipping, or adjustments "within specs" that are too extreme. To remedy this, units must be returned to Canon for precise adjustments. If this situation is real, it is not acceptable.

4. RAW pics from the average 7D (some may be sharper others less sharp) require MORE sharpening both in RAW and JPEG. Phototestcenter.com suggests an amount of 7 in DPP in sharpness for the 7D - that's the maximum. Similarly, many sharpening blogs and sites suggest higher levels of sharpening in ACR or DPP for the 7D.

5. The sensor of the 7D may outresolve some lenses. This has never been proven by accurate testing. However, it may make sense that average glass produces mediocre results with the 7D where it produces acceptable results with say a 350 D. Thus, avareage glass may introduce softness and/or artefacts on RAW pics.

6. Many posters and bloggers report that with the 7D, aperture must be kept fairly wide open, say between f 2 to 4, which is contrary to classic practice where the sweet spot of lenses used to be around f 5.6 or 8.

7. ISO, speed, stability. It appears the 7D will not be very forgiving in instances of underexposure, even by half a stop, by introducing noise at sharpening. Low speeds are not forgiving either with or without IS.

Conclusion of Conclusions: if you're not sure, have your 7D inspected and adjusted by Canon, that is, by a reputedly good service center. If your 7D comes back adjusted or within specs, then it's a matter of learning how to use this small pixel sensor, the area where all difficulties arise. Small pixels, and a lot of them, equal trouble.

ForumParentFirstPreviousNextNext unread
Flat view
Post (hide subjects)Posted by
ForumParentFirstPreviousNextNext unread
Keyboard shortcuts:
FForum PPrevious NNext WNext unread UUpvote SSubscribe RReply QQuote BBookmark post MMy threads
Color scheme? Blue / Yellow