My equipment ¤ TEC 140

After some problems with customs finally I became an owner of a nice apochromatic refractor made by Telescope Engineering Company - TEC.
I ordered the scope in the US and I was waiting for picking it up from August 2004 till April 2005.
It seems that it paid off. TEC 140 is sold with a high quality focuser Feathertouch 3545 manufactured by Starlight Instruments.

Technical specification:

Aperture: 140 mm
FL: 980 mm
Resolution: 0.8 arcsec
Weight: ca. 8.5 kg
Length (dew shield out): 140 cm
Length (dew shield in): 100 cm

Lens of this refractor are 140 mm large and it is a triplet design with ED glass.
The surfaces between glasses are filled in with special oil (oil-spaced lens). Such a design enables to have only two surfaces to be coated in comparison to air spaced design where there are 6 surfaces to be coated.
The more surfaces the more light loss as even best coated surfaces will reflect some light and lens' efficiency goes down. It translates into a loss of contrast.
Oil spaced lens were used in the highest quality apochromats - Zeiss APQ.
Lens of this design are coma free and are called - Aplants.