Click on the "Search" link in the menu above and type in "IGF", you will come up with every post that has anything and everything about IGF. If you type in "LR3IGF-1" you won't get everything because some people add spaces, dashes, typo's , etc., but IGF is hard to typo. Then read every thread and you will have all your questions answered and become a relative expert on LR3IGF-1 yourself. There is a ton of good info on this board on the substance. The "Cycles" threads/posts have a lot of real world info in them also.