I am new to all grain. Here is my question. I brewed a porter. Mashed and sparked. Before the boil took a hydrometer reading and temperature reading. Using the gravity correction chart on page 35 of Designing Great Beers by Ray Daniels I added the correction and missed my OG by .01. I added a pound of DME and boiled. I took another reading after the boil and was over my gravity by .01. My question is if I take a reading after mash and sparge, how do I know if I am going to get close to the OG? Appreciate any help!