Start posting MD5s of your DC42s
BLU 0.10
MD5 (BLU010.dc42) = fd526ea9e045d2024f832c45b7929d29
Xenix 2.3 Twiggies
MD5 (Xenix1of5.dc42) = 1fac4eafbc3567bc50ef5f3a826581d3
MD5 (Xenix2of5.dc42) = 003b436f821c715e57c0ec8d5d61f2fc
MD5 (Xenix3of5.dc42) = 40f71ac5d01e625d384ef51c23362452
MD5 (Xenix4of5.dc42) = 59bdcf071539b610032cb119d9e9f1ea
MD5 (Xenix5of5.dc42) = 40682b206e02b38b3759ad750ac36c28
Modified for X/ProFile per
http://sigmasevensystems.com/xpf_xenix.htmlMD5 (Xenix1of5Mod.dc42) = fda0c629208de4d812c06878c20cab5b
MD5 (Xenix2of5Mod.dc42) = a7da78e7eff741b473c05903a1b78cba
The Xenix images checksummed above were created with BLU 0.07 (which appears in the DC42 header), so another image of the same disk with a different version of BLU will have a different MD5.
Hence the suggestion to MD5 only the data portion of the DC42, eg:
hexdump -v -e '"%X"' -s 84 -n 871424 Xenix1of5.dc42 | md5 = 1c5935aa5eb3aec6b32d160a2349d97d
hexdump -v -e '"%X"' -s 84 -n 871424 Xenix2of5.dc42 | md5 = e3ab77488bb12de3ecd68fb0e9d56d32
hexdump -v -e '"%X"' -s 84 -n 871424 Xenix3of5.dc42 | md5 = 4fe11fefe374e319b1a0552f0e190202
hexdump -v -e '"%X"' -s 84 -n 871424 Xenix4of5.dc42 | md5 = 90251cf641728321277f3b15ce0b948c
hexdump -v -e '"%X"' -s 84 -n 871424 Xenix5of5.dc42 | md5 = 6dfac516dc2b0ddd49ab01ad939478ca
where "-s 84" skips the first 0x54 bytes (the DC42 header) and "-n 871424" considers only the 0xd4c00 bytes of data (excluding the tags).
the md5 is performed on the hexdump, which I used only for the convenience of it having -s and -n parameters.
The decimal number of data bytes in a non-sparse DC42 image are
Twiggy 871424
400k 409600
800k 819200
edit: added hexdump suggestion example