Can't get good resolution on second monitors
I've tried two 24" TVs/monitors as second displays with my imac9,1. Both are sold as dual purpose--either TV or computer display--and both are HD resolution @ 1080. In both cases the perceived resolution is poor. I'd decribe it as grainy, with poor contrast, in spite of extensive adjusting and calibration of the software available with each and physical monitor settings. As televisions, both deliver a great picture, but as monitors, they are terrible.
I don't need fancy graphics or cinema, but I do need good resolution for documents--letters and numbers--that I hope would come near what the iMac delivers. I'm not knowledgeable about display technology, and I sure would appreciate some recommendations.
Thanks for any help you can give me.
iMac (24-inch Early 2009), Mac OS X (10.6.8)