The Lunar Eclipse was visible on Saturday, 4th April 2015, 8.40pm from Singapore and Malaysia. The moon has passed part way through the earth’s shadow and was partially lit by the sun on its way back out.
There are two effects that produce the red colour.
1. Just as a sunset looks red due to the scattering of the blue light more than red light by air molecules. So mostly red light makes it through earth’s atmosphere on its way to the moon.
2. The refraction effect of light due to the different speed of light in the vacuum of space versus air.