Koopman was in charge of RKC Waalwijk's clash with Twente Enschede, and awarded Twente a controversial opener after just two minutes.
RKC keeper Khalid Sinouh's blunder in letting the ball roll towards his own net proved costly, as Koopman awarded a goal on the advice of one of his assistants.
Replays showed the decision to be wrong, which cost RKC dear, as Twente went on to win 2-1.
Koopman reviewed the incident after the game and deserves credit for admitting he was wrong, but feels the authorities could give officials a helping hand.
"I am responsible for the final decision," said Koopman. "But I followed the advice of my assistant.
"The replays show that the ball did not go over the line.
"This demonstrates the need for cameras."
Sinouh has admitted his disappointment at the events, saying: "I just wanted the ground to swallow me up.
"I cannot believe it, I could cry, but the ball didn't go in."