I don’t know diddly about resolution/pixels/yadda yadda. But I do have an idea about how to settle this matter once and for all, if Jim Robinson is so inclined:
I will send via certified mail to Jim the certified, embossed copy of my birth certificate (which is an abstract, as is Obama’s), the postmarked envelope in which it was sent from the Hawaii State Department of Health, and the receipt that was included for the purchase of this duplicate under the agreement (which he and I can arrange privately) that only limited info that I agree on is released if he chooses to post it. I live in CA now, but Fresno is too far for me to drive to make a delivery. Jim already has my personal info because I am a donor, so I am not worried about him revealing the info on my BC. I don’t know if Jim even wants to get into this, but the offer is open.
To paraphrase what opendna said, this is roughly the equivalent of trying to determine if a particular bank note is valid by looking at a .jpg of it posted on a web site.
With glaring differences between the Decosta BC and the BHO BC we could be sure that one is a fake. Since your known good document is much closer to the BHO BC than the Decosta BC, I must conclude that the Decosta document is fake. In the absence of examining the paper BHO document, I can't conclude that the BHO BC is valid, but the case for it is much stronger than I thought when I got up this morning
At this point, I'm content to accept the BHO BC as genuine, pending further information.
This doesn't mean I think he's qualified to be President! It just means I think he probably meets the minimum Constitutional requirements for the job.