Pure Yellow Oncidiums

I have two pure yellow 'Golden shower-type' Oncidiums.  One of them is from MH nursery while the other is from WL nursery.  The one from MH nursery can truely be considered pure yellow because there are no markings on the flower at all.

The flower above belongs to the plant from WL nursery where some greenish yellow markings can be seen on the petals.  The flower below came from MH nursery.  The plant itself is smaller in size and the flower is pure yellow without any markings.  Both of them are highly sought after for their pure color.