The match was televised live by Sky television but spectators at the game struggled to identify players on both teams. Play was briefly halted but officials then decided the game should continue in the gloom.
Hunslet were looking to bounce back from a 38-12 defeat at Batley last Sunday, but Dewsbury, fresh from a free weekend, were quicker out of the traps and deserved the points.
Kyle Bibb and Josh Tonks were both held over Hunslet’s line on their backs before home winger Richie Barnett fumbled Dominic Brambani’s high kick to gift-wrap a try for second rower James Lockwood.
Brambani’s penalty, for laying on in the tackle, extended the Rams’ lead to six points and they continued to look the better side, with Hunslet making too many mistakes near their opponents’ line.
Brambani kicked a second penalty before Tommy Haughey barged his way over at close quarters on the right for Hunslet’s only points, just before half time.
The referee consulted the big screen before sanctioning Buchanan’s try in the left corner, 16 minutes into the second half, and Buchanan sprinted in again six minutes later, Brambani failing with both conversion attempts.
Substitute Aiden Faal grabbed the Rams’ fourth try, against his old club, Brambani’s successful kick making the score 22-4 in favour of Warren Jowitt’s men.
Hunslet Hawks: Kain; Ratcliffe, Kear, Clayton, Barnett; Grimshaw, P March; Yates, Haigh, Kelly, Dooler, Haughey, D March. Substitutes: Chapman, Helme, Houston, Oakes.
Dewsbury Rams: Glynn; Wainwright, Crossgrove, Bolger, Buchanan; Brambini, Wandeless; England, Blake, Bibb, Spicer, Lockwood, Tonks. Substitutes: Menzies, Horton, Walker, Faal.
Referee: T Roby (York).
Wakefield Trinity Wildcats have signed Liam Higgins from Sheffield Eagles until the end of 2012.
The ex-Hull FC prop made more than 100 appearances with Castleford Tigers before dropping down into the Championship this year.
However, Higgins, 27, has now returned to Super League and could make his Trinity debut against Huddersfield Giants on Sunday.
Coach John Kear said: “Liam is a player that we tried to sign in the off-season, a strong, powerful prop and I’m delighted he is with us now.”
Disgraced London Skolars head coach Joe Mbu, and assistant Oliver Bloom, have both been banned from the touchline for six months after being found guilty of running in and punching during a brawl that erupted against Doncaster last month.
Englishman Vinny Webb has been appointed coach of the Russian national side for this year’s European zone qualifiers for the 2013 World Cup.