Have seen color, size, profile, etc matter with blackfish, especially clear water, but with whites, they'll bite dang near anything they see I think. Not talking about upper end, older year-class fish, just crappie in general. Blacks will make you beat your head against the wall some days. We get a mix of them in some of the lakes and you can just about tell on scope when a white hits. That rascal will launch from a mile away at times it seems. I hooked one near a log, hung up, broke off, he shook free, and I kept a watch on him, re-tied, and pitched back down to him and he ate. I swear if they didn't reproduce at such a fast rate they'd be extinct.