Different people use Photoshop in different ways, but here&#x27;s some feedback with respect to curves vs levels:<p>Curves can do everything that levels can do, and more. If you understand curves, you really shouldn&#x27;t need to use levels, and you certainly don&#x27;t need to use both right next to each other, applied to the whole image. I cringe a little bit whenever I see people use multiple levels and&#x2F;or curves adjustment layers in succession. Not only is it unnecessary, but you&#x27;ll be <i>throwing away</i> color information. You&#x27;ll see evidence of this in histogram combing and color banding. Of course, it may make sense to have several local curves adjustment layers that apply to isolated areas of an image (e.g. with masks), but it&#x27;s generally a mistake to use multiple global curves (or levels) adjustment layers in succession.<p>It&#x27;s probably not much of a problem for illustrations with flat colors, but you&#x27;ll definitely notice it in gradients and photographs.