We are using the objective-type TIRF setup to check Cy3 signals. However, there were always some weird patterns appearing in the epi mode and TIRF mode with 60X objective only when we were using confocal dishes. We tried to replace the Cy3 filter set and Texas Red filter set, but the patterns are still there. There are no such patterns in glass coverslip or in other laser channels when using confocal dishes. Do you know about this phenomenon?

The objective we used to detect signals is Apo TIRF 60X/1.49 oil. I think it is probably because of the objective as we tried a similar test in the confocal setup with the same Cy3 and Texas red filter, and there were no patterns. If you have any ideas or comments, please let me know.

Thank you so much.