Hi Thomas,

deep optical imaging of NGC 1399 is presented in Tal et al. (2009) - but it is of the galaxy itself, rather than the Fornax Cluster.

http://iopscience.iop.org/1538-3881/138/5/1417/pdf/aj_138_5_1417.pdf

Larger portions of the central Fornax Cluster have been observed in Washington colours by Dirsch et al. and Bassino et al.

Moreover, Bergond et al. (2007) selected their intra-cluster globular candidates

from deep WFI mosaic camera at the La Silla ESO/MPG 2.2-m telescope - but I have not found any publication of the photometry itself.

Cheers,

Ylva

Try this - its old , but was pretty deep

http://adsbit.harvard.edu/cgi-bin/nph-iarticle_query?1991ApJ...376..404B

but there are several more recent CCD based surveys as well