這裏有一些消息
http://news.techwhack.com/1878/canon-5d-is-finally-unveiled/可以看出來Nikon也有在做FF sensor，只是目前成本的問題還沒解決。
"This camera is going to intensify the pricing pressure that
Canon’s competition faces. Nikon prototyped the full frame
sensor this year but it has not utilized it as the cost per
FF sensor is up to 20 % higher than Canon’s. The 5D has been
under consideration for a long time but Canon did not bring
together a development team to actively pursue the 5D because
the full frame sensor was very costly to manufacture and yield
rates were not high enough to incorporate this sensor into
lower price Canon bodies. Canon has met its product goals for
the 5D but yields for the full frame sensor are still causing
some internal concerns."
現在FF sensor的良率比起1Ds MarkII推出時有很大的進步。所以價錢能down
一下是應該的。但是比起APS size的良率還是太低，只有25%。如果以後可以再
提升良率，(或是用12"晶圓?) 或許FF sensor的成本還可以再進一步的down下來。
Canon manufactures its sensors from 8 inch wafers(200mm dia).
One 8 inch wafer yields 20 FF sensors(if there are no defects)
but presently yields are at 25 %. Seventy two 1.6x(22.7x15.1mm)
sensors can be made from one 8 inch silicon wafer. Yields for
1.6x sensors per silicon wafer are at 70+ %. So therefore,
with each LSI batch, there are about 5 usable FF sensors for
every 50 1.6x sensors. At the time the 1Ds-Mk2 was released,
yields were 10 % per wafer. With fewer usable FF sensors per
wafer, production costs per sensor were significantly higher
and this reflected on the 1Ds’s price when it was released.
Canon sells far fewer 1D series bodies than the 1.6x 20D and
Kiss n Digital’s. Optimizing and increasing the yields is a
slower process for FF sensors.
