The C11 telescope was send to Ralf Ottow for check and improving the collimation and optics. He checked the optics and he said that this C11 was better then C11 median telescopes and one of the better C11 telescopes he has seen in his hands. He is an expert in the field of optics and cassegrain telescopes, he checked the optics and mechanics and did several improvemnets. After that and was send back, i could check the telescope i have now visual nice sharp stars. Thank you Ralf Ottow!