These visualizations were generated by compositing the small field-of-view, high-cadence closeups of Venus with the full-disk, low-cadence imagery from Solar Dynamics Observatory (SDO). Two different instruments are used: the Helioseismic and Magnetic Imager (HMI) which sees light in the visible range, and the Atmospheric Imaging Assembly (AIA) which sees light in several wavelengths in the ultraviolet range. To find out more information about these instruments, check out The Atmospheric Imaging Assembly Tutorial.
Some artifacts may be visible from the compositing, but you have to look pretty closely to see them.
The color table threshold was raised for these images, reducing the amount of noise visible in the images.
Note: There is an interesting artifact worthy of mention and clarification, and that is as Venus crosses the solar limb, the limb appears to be visible through the planet in some of the imagers (most notably the ultraviolet channels). Discussion with the scientists who built the imagers suggest this might be 'crosstalk' between the readouts of the four CCD panels that make up a complete image. It is an artifact of the imaging system.
GCMD keywords can be found on the Internet with the following citation:
Olsen, L.M., G. Major, K. Shein, J. Scialdone, S. Ritz, T. Stevens, M. Morahan, A. Aleman, R. Vogel, S. Leicester, H. Weir, M. Meaux, S. Grebas, C.Solomon, M. Holland, T. Northcutt, R. A. Restrepo, R. Bilodeau, 2013. NASA/Global Change Master Directory (GCMD) Earth Science Keywords. Version 188.8.131.52.0