I was using text ads and use to get upto $.75 per click and then I tried to experiment with Image ads and i never received $0.01 per click What can be the reason for the same?
Usually ppc ads are not attractive while cpm ads are very attractive and they have good click through rates. The reason is nothing but the companies are putting ads for their revenue, not your/ours. It's the same in the case of text ads and image ads. That's why i am using CPA Gateways instead of ppc's. You can also use CPA gateways along with Google Adsense.
I have found the complete opposite. I have been experimenting with 2 ads 120x600 and a 728x90 So far the image ads are paying higher than the text ads on both which has ranged in the past two month of .25 to 1.79 clicks for image and the text ads from 3 to 54 cents now the 728x90 ads are paying higher than the 120x600 ads in both ads. I also have the 350x250 image and text which has been paying good and also on some smaller pages 120x120 text ads which do not get many clicks but not one has been under 30 cents. These ads are only on half the site which will be going on all pages soon.