Two years ago I observed it with DSLR camera (Canon EOS 600D) attached to a Sky Watcher 150/750 Newtonian. Now I made observations using cheap uncooled CMOS camera ZWO ASI120MM-S. This camera positioned as a planetary and guiding camera. It has a small 1/3" chip, which is its main drawback. Yet a field of view of the setup (~16'x22') turned to be sufficient for many interesting variables, such as T UMi, RX UMa, AE UMa, etc.
Here is a comparison of data for AE UMa obtained using ASI120MM camera + Baader photometric V filter with the data obtained using Canon EOS 600D camera.
In both cases, data were transformed: for ASI120MM+Vfilter one-filter transformation was performed (using the previously defined Tv_b-v coefficient and an average color index of the variable); for Canon EOS 600D two-filter transformation using green and blue channels was done (again, using previously defined Tv_b-v, Tb_b-v, and Tbv coefficients).
Exposure per point was 45s for ASI120MM (for each point 3 frames by 15s were stacked) and 30s for Canon EOS 600D. So integration times are roughly compatible.
It is seen that the ASI120MM camera shows better photometric performance (lesser scatter).
The data reduction process with ASI120MM is simpler and much faster.
So in cases where the wider field of view is not required, ASI120 is probably a better choice. I plan to use it in parallel to DSLR for photometry.
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