Image forming apparatus

An image forming apparatus comprising:

• a first carriage having a first recording head to eject black liquid droplets and movable in a main scanning direction;
• a second carriage having a second recording head to eject color liquid droplets and separatably dockable with the first carriage;
• a position detector comprising a positional reference marker provided to the first carriage and a position reader provided to the second carriage to read the positional reference marker, the position detector detecting a position of the second carriage relative to the first carriage in a state in which the first and second carriages are docked with each other;
• and
• a landing position corrector to correct landing positions of liquid droplets ejected from at least one of the first and second recording heads, the landing position corrector holding the position, obtained by the position detector upon correction of the landing positions, of the second carriage relative to the first carriage, as a reference position of the second carriage and adjusting a correction amount for correcting the landing positions based on an amount of shift between the reference position and a present position of the second carriage relative to the first carriage docked with the second carriage for image formation.