The leaves CAN be a lighter green, but if the plant is producing flowers, it's happy.
If it's not, think about how to provide it with just a little more bright - not direct - light.
The light spot that you have may be from trauma to the leaf (a sharp edge or something). It doesn't look like a fungus, virus or sunburn to me.
Others please jump in with opinions.
It recently finished blooming. I dont remember anything hitting it but you never know. I thought Catt's could handle direct sun. It gets a good few hours of morning to midday sun, but the leaves still seem a bit dark to me.
Most "cattleyas" cannot take full on sun...the majority prefer bright indirect light. You'll know if the lighting is right if your plant starts to get a purple tinge to the leaves and bulbs. If your leaves are turning yellow or have yellow spots on them, my guess would be that it's getting direct light through a window - the window then turns into a magnifying glass so-to-speak. Midday sun is usually not advised as it is very intense at that time of day and you could run the risk of burning your plants.
Last edited by CoolPhrog; 02-28-2009 at 10:54 PM..