How is everybody today
I just got time to try out my 50 nifty with kenko Extension tubes,, and yes they costed me less than Canon 100mm macro and really got close to the objects with the built in flash ! although i have the 580 flash but used the built-in flash to proove how cheaply you could build your macro gear 
in the test i used Canon 500D
will start with some Spider pic's, here i only used 36mm+20mm tubes ! that makes up to 1.24X according to kenko standards, which is pretty decent i quess
this is a very small jumping spider about 6mm !!
1:
HTTP response: NOT FOUND | MIME changed to 'image/png'
2:HTTP response: NOT FOUND | MIME changed to 'image/png'
These two pic's where taken at F22,, yes guys try this out and trust me you'll love the results,, open up the build in flash, then set the camera to manual and try some thing like F22, 1/200 sec which is max for flash sync, iso 100-200 no need for more 
since the object is very close
Good luck and im here for any questions, i'm still a beginner in macro but i hope i could help anyone
