1、在PS中,按下CTRL+N,新建文档。再从工具栏中调出圆形选框工具。
![](https://video.ask-data.xyz/img.php?b=https://iknow-pic.cdn.bcebos.com/7af40ad162d9f2d3c3b79544a7ec8a136227ccf3?x-bce-process=image%2Fresize%2Cm_lfit%2Cw_600%2Ch_800%2Climit_1%2Fquality%2Cq_85%2Fformat%2Cf_auto)
2、鼠标移到画布中,画出一个圆形选区。
![](https://video.ask-data.xyz/img.php?b=https://iknow-pic.cdn.bcebos.com/d01373f082025aaffab5cf60f5edab64024f1a91?x-bce-process=image%2Fresize%2Cm_lfit%2Cw_600%2Ch_800%2Climit_1%2Fquality%2Cq_85%2Fformat%2Cf_auto)
3、想要把这选区放大或缩小。那么,可以这样操作:鼠标移到选择菜单这里,点击,弹出下拉菜单再点:变换选区
![](https://video.ask-data.xyz/img.php?b=https://iknow-pic.cdn.bcebos.com/fd039245d688d43fba282059731ed21b0ff43b93?x-bce-process=image%2Fresize%2Cm_lfit%2Cw_600%2Ch_800%2Climit_1%2Fquality%2Cq_85%2Fformat%2Cf_auto)
4、此时,矩形选区就有了变换框,变换框上有八个节点,鼠标放在右上角的这个节点上,左手按住Shift,右手用鼠标点住再向外拖拽。即可把选区等比例放大。
![](https://video.ask-data.xyz/img.php?b=https://iknow-pic.cdn.bcebos.com/c75c10385343fbf263ac1788be7eca8064388f9d?x-bce-process=image%2Fresize%2Cm_lfit%2Cw_600%2Ch_800%2Climit_1%2Fquality%2Cq_85%2Fformat%2Cf_auto)
5、左手按住Shift,右手点住鼠标向框内推,即可等比例缩小选区。
![](https://video.ask-data.xyz/img.php?b=https://iknow-pic.cdn.bcebos.com/0b55b319ebc4b745281606bdc1fc1e178b82159e?x-bce-process=image%2Fresize%2Cm_lfit%2Cw_600%2Ch_800%2Climit_1%2Fquality%2Cq_85%2Fformat%2Cf_auto)
6、确定选区大小后,按下回车键,变换框隐藏,操作完成。
![](https://video.ask-data.xyz/img.php?b=https://iknow-pic.cdn.bcebos.com/8694a4c27d1ed21b4f369f4ea36eddc450da3f99?x-bce-process=image%2Fresize%2Cm_lfit%2Cw_600%2Ch_800%2Climit_1%2Fquality%2Cq_85%2Fformat%2Cf_auto)
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