I have not done many clusters but gave this one a good go. Nine doublings of exposure gives a dynamic range of potentially 20+ bits.
Large Image 1.5MB
http://members.optusnet.com.au/~fmlee/NGC3532_2.jpg
Details
Canon 5DH. 100ED with AP FR/FF f/6.7, Hutech LPR filter.
250ISO 5x(7s, 15s, 30s), 500 ISO 5x( 30s, 1m, 2m, 4m), 1000ISO 5x(4m, 8m) with fridge at 4C. Converted from RAW to TIFF and corrected for flats with images plus. Aligned with Registar and generated an LDR from this data with EasyHDR.
I have put up a better version.
Bert