Due to the last few years, it has become apparent that the History Channel isn't what it describes itself to be. So I ask; how credible is the most recent "Gettysburg" documentary currently on Netflix compared to the Ken Burns PBS Civil War series?
I ask this as a UK resident interested in the Civil War after my granddad recommended the (what I would say) wonderfully written historical novel "Killer's Angels" by Michael Shaara; which I'm assuming was written in the fictitious way as Simon Scarrow's "Fields of Death"
Before I get too in depth into the subject, I'd like to make sure I'm at least on the right tracks in delving into this subject; and if not, could somebody point me in the right direction?
Unfortunately, I haven't had a chance to watch Gettysburg yet. But from what I do know about it I would consider it to be the tv show equivalent of Killer Angels. You are correct about Killer Angels being a historical fiction novel, as Michael Shaara is not an historian.
There has been a decent bit of criticism of Ken Burns, including a book that was put out by the different historians. This is an excellent review of the different positions the historians take regard the series.
The Gettysburg documentary... is not so good. They had some great historians working on the project, but it wasn't produced by historians, and their reliance on reenactments that were often terribly inaccurate is pretty bad.
The Ken Burns film has a lot of flaws. Don't take anything that you hear in it as gospel truth, he makes choices for dramatic purposes that are not based on historical reality. Reading the Killer Angels and watching the Ken Burns film will give you the impression that the 20th Maine's fight on Little Round Top was the most important part of the second day of Gettysburg, but in reality it wasn't that important (while the fight in the Wheatfield and along Cemetery Ridge is glossed over, and the fight on Culp's Hill is essentially ignored).
That being said, the Ken Burns film is a good entry into the subject. You'll get a decent overview of what happened, though it's biased towards the Eastern Theater of the war.
If you're looking for a good read, Bruce Catton is an excellent author for someone first getting interested. Again, it's pop history so there's more drama there than historical rigor, but these are things that get you more and more interested than you were before.
If you're looking to learn more about Gettysburg, my suggestion is "The Gettysburg Campaign: A Study in Command" by Edwin Coddington - probably the best one volume study of the campaign.
And if you can find a copy of Allan Guelzo's book about the campaign, "The Last Invasion", I highly recommend... burning it and burying the ashes.