英语语法分析

Improved the focusing accuracy when using the EC-20 Teleconverter.

改进了对焦准确时，用欧共体20个镜头。

Palmer made this digital photo with a 500mm lens and a 1.4x teleconverter.

帕默用500毫米镜头和1.4倍的望远倍率镜拍摄的这张照片。