Denis Andrade

The BTFI, or Brazilian Tunable Filter Imager, is a new interferometer and imager being developed through a consortium of national and international institutes. This instrument will be part of SOAR telescope in Chile. The new technology employed in the equipment is extremely versatile because it introduces the concept of iBTF (Bragg Tunable Imaging Filter) and a new model of Fabry Perot which one etalon works in a wide resolution range.
The BTFI is being designed to observe faint sources and its detector will work in "rapid scanning" mode, ie, multiple fast readings are made and then summed to obtain the total exposure time needed. Through the technique of "rapid scanning", problems related to "seeing" and atmospheric turbulence in long exposures are eliminated when we calculate the average of all frames.
However, common CCDs, can't be used in this type of observation because of the readout noise of each frame would be very large relative to the signal. To avoid this problem is used a new technology in CCD, the EMCCD (Electron Multiplying CCD). The advantage of the EMCCD is to have an almost zero reading noise when working in "photo counting" mode.
Learn more about the project here: BTFI.