2D data formats are very specific (unlike 1D which most people default to the same general format).  now that the NeXUS NXcanSAS standard reduced data format has been approved, we are trying to encourage its use to avoid exactly this kind of problem.  Bruker poeple have attended some of the canSAS meetings where the standard work was discussed and now that it has been approved I encourage you to ask them to output their data in said format.  

In the meantime, for legacy reasons only, SasView also supports the NIST 2D ASCII format.  Further, as you discovered, SasView has a converter which will convert ISIS 2D ASCII format as well as the BSL/OTOKO 2D format. Question: What type of ASCII format are you getting from Fit2D? My guess is that the error is because the format is not a supported input format to the converter? I am assuming this error is being thrown when you try to convert the data? I am well aware of Fit2D but have never used it so not sure what 2D output formats it supports, but looking online I'm not sure that its two ASCII 2D outputs (Spread sheet and MCA) are compatible?  It seems like Fit2D will output a BSL 2D? which the SasView converter should be able to handle.  It also seems to output a TIFF. If all else fails you can try that and use the image converter to see if it works?  

There maybe others who know more about the Fit2D output who might have some suggestions.  Otherwise please let us know how you get on and if I have misunderstood the problem please don't hesitate to ask again.

Cheers

Paul

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