There is a known issue in the Dicom Standard. SOP classes related to RT can legitimately be written / transferred using several different Transfer Syntaxes. HOWEVER The length of some of the attributes associated to RT is such that they can not be represented within a 32 bit word. As such it is imposable to represent them using an explicit Transfer Syntax.

Transfer Syntax Negotiation in DICOM is relatively simple, but often misunderstood.

Transfer Syntax Negotiation in DICOM is relatively simple, but often misunderstood.

Background in earlier versions of DicomObjects (both .NET & COM), the same basic mechanism was used for selecting transfer syntaxes:

The mechanism is quite different for the simple Send methods compared to using DicomConnection

As disk space usage has always been a priority when designing/implementing DICOM applications, “What is the best practice for writing DICOM files?