Download the caps instead of saving them one at a time from the gallery:
Note: For some reason the dvd files are a lot smaller than regular dvds, which means the caps are a lot smaller than the rest (and the quality isn't as good).

Season 1:
1x01 - The Journey Begins (1)
1x02 - Stranded (2)
1x03 - More Than Human
1x04 - Nectar
1x05 - Cave of Fear
1x06 - Salvation
1x07 - Bloodlust
1x08 - Out of Time
1x09 - Paradise Found
1x10 - The Beast Within
1x11 - Creatures of the Dark
1x12 - Tribute
1x13 - Absolute Power
1x14 - Camelot
1x15 - Unnatural Selection
1x16 - Time After Time
1x17 - Prodigal Father
1x18 - Birthright
1x19 - Resurrection
1x20 - Prophecy
1x21 - The Chosen One
1x22 - Barbarians at the Gate


Season2:
2x01 - All or Nothing
2x02 - Amazons
2x03 - Tourist Season
2x04 - Stone Cold
2x05 - Divine Right
2x06 - Skin Deep
2x07 - London Calling
2x08 - The Prisoner
2x09 - The Games
2x10 - The Source
2x11 - Trophies
2x12 -Voodoo Queen
2x13 - The Guardian
2x14 - Under Pressure
2x15 - The Outlaw
2x16 - Quality of Mercy
2x17 - Mark of the Beast
2x18 - Survivors
2x19 - The Pirate's Curse
2x20 - The Visitor
2x21 - A Man of Vision
2x22 - Into the Fire


Season 3:
3x01 - Out of the Blue
3x02 - The Travellers
3x03 - Eye for an Eye
3x04 - True Spirit
3x05 - The Knife
3x06 - Fire in the Sky
3x07 - Dead Man's Hill
3x08 - Hollow Victory
3x09 - A Witch's Calling
3x10 - Brothers in Arms
3x11 - Ice Age
3x12 - The End Game
3x13 - Phantoms
3x14 - The Secret
3x15 - Finn
3x16 - Suspicion
3x17 - The Imposters
3x18 - The Elixir
3x19 - Tapestry
3x20 - Legacy
3x21 - Trapped
3x22 - Heart of the Storm