# Problems with setMask and cacheAsBitmap

**URL:** https://forum.kirupa.com/t/problems-with-setmask-and-cacheasbitmap/277336
**Category:** flash
**Created:** [December 10, 2008, 10:23pm UTC](https://forum.kirupa.com/t/problems-with-setmask-and-cacheasbitmap/277336 "2008-12-10T22:23:02Z")
**Posts on this page:** 1
**Page:** 1

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### Author: ![madmotts](https://avatars.discourse-cdn.com/v4/letter/m/8e7dd6/32.png) [@madmotts](https://forum.kirupa.com/u/madmotts)
#### Post date: [December 10, 2008, 10:23pm UTC](https://forum.kirupa.com/t/problems-with-setmask-and-cacheasbitmap/277336/1 "2008-12-10T22:23:02Z")

</div>

Can anyone shed some light on opacity mask max width? I have discovered a max width of a movieClip that is masked using opacity to around 2800+. Masks w/o opacity don’t seem to have this problem.

holderMov = movieClip to hold stretchyMov & masker  
masker = movieClip with gradient black to black/opacity 0%  
stretchyMov = movieClip that is being scaled.[INDENT]\*\*[SIZE=2]holderMov.stretchyMov.cacheAsBitmap = true;  
holderMov.masker.cacheAsBitmap= true;  
holderMov.stretchyMov.mask= holderMov.masker;

holderMov.addEventListener(MouseEvent.MOUSE\_UP,onPresser);

function onPresser(evt:Event){  
holderMov.stretchyMov.width = holderMov.stretchyMov.width + 100;  
trace(holderMov.width); [/SIZE]**[SIZE=2]// at around 2800+ mask no longer works = no mask  
[/SIZE]**[SIZE=2] }

stop();[/SIZE]\*\*  
[/INDENT]