There are two versions of DCA for Swarovski ATM/STM telescope, namely DCA-fixed (model number 49306) and DCA-zoom( model number 49206). The former is for its 20X, 30X & 45X eyepieces, while the latter is for the zoom eyepieces. However, with the popularity of using the zoom eyepieces in the telescope and less people using the fixed eyepiece, Swarovski stopped the production of DCA-fixed a few years ago.
However, if you use the scope for taking photos and you ask for the better image quality, the 30x eyepiece is still the best among the eyepieces that Swarovski produced. Unfortunately, if you fit the DCA-zoom to a 30X eyepiece, there were a lot of problems. The most obvious is that the upper half of the DCA will not slide all the way down to the proper locking position on the bottom half of the DCA. The end result is that the eyepiece ocular opening is not on the axis with the opening of the upper half of the DCA. To solve these problems, our friend Chan C-fu modified the upper half of the DCA by replacing it with a longer tube so that the DCA upper half can now slide all the way down to the locking position . The whole system is now working properly on the 30X eyepiece as the old DCA-fixed system.
Anyone who need this
modified tube for their DCA-zoom , please PM me, I understand Chan C-fu still has four units in stock. Of course, you have to pay for it.
