Need some help with flats in Maxim please

[Revs]

Hi guys. After getting some data the other night I finally have something to play with in Maxim, but I'm having a bit of fun. The problem is as follows;

I have 5 lights, 5 darks, 10 flats and 10 bias'. I've sussed out how to set them up in calibration but whenever I use the flats, the resulting image is almost totally black, with only the brightest bits show at all.

If I calibrate the image with just the darks and bias' it's fine, but add the flats and it kills it. I suspect the process is subtracting the flats from the lights instead of using them to balance out the brightness, but I'm not sure. Anyone have any ideas as to what I might be doing wrong?

TIA

[Revs]

Just found this thread... http://stargazerslounge.com/imaging-image-processing-help-techniques/149453-how-do-you-subtract-darks-flats-using-maxim.html .... where Steve says...

Select the FLATS group in the top window and set attribute of Combine Type 'median' and tick the 'apply boxcar filter' box

I think I've been using the 'average' setting and wasn't applying the filter. I'll have another go at this tonight with these settings.