Correct, you do not want to use numbers that you used for PV 2003 directly with PV 2010. Particularly when using extreme numbers, results will be poor. You gave one example earlier with sharpening. Another one is NR. For example, suppose you shot an ISO 6400 image in the past and previously tried LR 2's NR (equiv of LR 3's PV 2003). To try to minimize color blotches, you cranked the color slider all the way up to 100. Well, due to the new methods and calibrations used for PV 2010's NR, a "Color" noise reduction slider value of 100 is likely to be way too strong. If you have an image at PV 2003 and want to see what it looks like at PV 2010, you may want to reset sharpening & NR set to their default values (maybe we should take care of that automatically when you click on the warning icon).
Some sharpening tips:
- Yes, it is true that if you crank sharpening's Amount and Detail both up, things will get crunchy and look bad.
- However, if you crank Amount up but turn down Detail, I believe that you can get very useful sharpening results. Better edge definition without texture emphasis.
- Similarly, if you crank Detail up but turn down Amount, I also believe that you can get useful sharpening results, and different from the previous (i.e., high amount, low detail). The latter in particular will accentuate texture. If you don't want to bring out texture (e.g., in skin!), keep Detail down.
This is why the slider range is there. It's not there so that you can crank up all the sliders and hope you get something useful.
As an analogy to another set of controls ... I guarantee that if you crank Exposure to +4, Brightness to +150, and Fill Light to +100, you probably won't get anything useful, either. (i.e., the image will become basically all white -- not very useful). But you can do useful things with high Exposure and low Brightness, or vice versa. The former brings out highlight detail and compresses midtones & shadows; the latter does the opposite.
One more tip:
- If you want to fine-tune sharpening in a part of the image, without affecting other areas, try local sharpening (e.g., via the brush). If you've already applied capture sharpening to an image but find it's a little too strong in a specific area (e.g., the catchlight), try using a brush with negative sharpening to "back off" on the sharpening in that area alone.