Deadman waved away strong penalty calls for both sides and ruled a Ricardo Fuller goal offside to leave Powell disappointed and frustrated.
"It is exasperating," he said. "For me the officials have got some big decisions wrong and that is disappointing and frustrating.
"There was what looked like a clear-cut penalty in the first half and another in the second - and if you ask Tony he will tell you that Middlesbrough might have had one as well.
"That said, I was pleased with the performance if not the result.
"We started off very well and were in a good place and maybe we let it drift a little and that left me a bit frustrated.
"It was a real shame we couldn't convert some of the really good chances we converted."
Charlton's draw means they will fall just short of the play-off places after a late surge.
"I'm pleased with the way the team have performed after coming up a league," said Powell. "It is a credit to the group and bodes well for next season."
- Sports & Recreation
- Ricardo Fuller