Do you have software to write synthetic raws in some known raw format?
I would like to do some raw converter tests.
The short story is that I unfortunately probably do not have the program you need for your testing
The full story is this; I contribute to RawTherapee (open source project) where I've made some key contributions to support medium format gear, and I'm also one of the developers making the commercial software Lumariver HDR, which does high class merging, tonemapping, and flatfield (LCC) correction and supports raw-in-raw-out workflow, primarily native-raw-in-DNG-out. The commercial value of supporting MF gear is not exactly big, but as I'm a MF shooter myself and need those features myself we do it anyway.
Anyhow, Capture One is popular among MF shooters, and Capture One happens to be poor at tonemapping (good for us) but also quite poor at dealing with DNG files (bad for us), which cripples Lumariver HDR's raw-in-raw-out workflow. The solution to this problem was to take the most popular MF format, Phase One's IIQ, and make a format writer for that. So then you can take your Phase One native IIQ raw, import that to Lumariver HDR, LCC-correct (crosstalk cancellation feature coming), tonemap, and then export to an IIQ raw which you then open as any normal raw file in Capture One. (This feature has not yet been released.)
As a side effect of having an IIQ writer it's also possible to import say a Hasselblad H5D-50c or Pentax 645z file and write an IQ250 IIQ file. It will only work color-wise if sensor CFA matches, and since Capture One ignores lots of its own IIQ tags and just goes on the model id tag, sensor size must also match an existing Phase One digital back model. The IIQ writer is not part of my open source effort so I can't just give it away. The feature is intended for Phase One digital back owners, so in the released product we will most likely not enable the possibility to import another format and write an IIQ (it won't work in most cases anyway for the reasons described).
I'm myself very curious about comparing these three cameras though, so if anyone provides raw files to me I can convert them so people can play around with it.
If you with synthetic raws means synthetic image data content it's not adapted to do that (ie the raw image data must come from a raw file). It's quite easy to add such a feature though, but we've had no reason to do so so far. The two raw formats we write is DNG and IIQ, and as said the only reason we write IIQ is because Capture One's DNG support is not satisfactory, at least not yet.