Binarize the image for character recognition

I am trying to recognized characters from the images taken from mobile camera at 72dpi resolution with in 2-2.5 secs with complete processing. Can be found in the following link

Tickets for OCR

Ticket contains

    little bit bad light
    Non-text area
    less resolution

I tried to feed the image direct to tesseract API and it is giving me 70% good results in 1 sec average. But I want to increase the accuracy in noticing the time factor So far I have tried

    Detect edges of the image
    Blob Analysis for blobs
    Binarized the ticket using adaptive thresholding

Then I tried to feed those binarized images to tesseract, the accuracy reduced to less than 50-60%, though binarized image look perfect. I also tried to look in to few research papers

http://www.vincent-net.com/luc/papers/10wiley_morpho_DIAapps.pdf

http://citeseerx.ist.psu.edu/viewdoc/download?doi=10.1.1.193.6347&rep=rep1&type=pdf

http://iit.demokritos.gr/~bgat/PatRec2006.pdf

http://psych.stanford.edu/~jlm/pdfs/Sternberg67.pdf

but no luck. Kindly help me in this and sorry if my question is so basic.