Artesky introduces the new line of APO ED refractors, the new 102mm doublet with 2 element objective, the first is a FCD1-B Ohara (Japan) element while the second is a Lanthanum element. It is possible to reduce it with a factor of 0.8x and bring it to a focal length of 570mm with factor F/5.6 or use it at full focal length with the 1x variable field flattener.