In my experience preprocessing the image is extremely important before feeding it into Tesseract. I tried to do the same as OP on a rainy afternoon but shelved

In my experience preprocessing the image is extremely important before feeding it into Tesseract. I tried to do the same as OP on a rainy afternoon but shelved the project after it became more of a imagemagick research task than about creating a database of my receipts. I got Tesseract to recognize about 80% of the text but it was still missing some letters from slightly worn-out receipts.