Which would result in power increases/decreases as I mentioned above. Remember the energy doesn't enter the field as one uniform block. With Temporal Sludge for example front enters first and slows down while the energy behind that is still traveling the same speed. This results in any energy entering bunching up which increases the power since the same energy is being delivered over a shorter timeframe.It gets slowed down to match the time dilation. So while a Flare Shooter fired at someone in a TS is faster for them when it's still outside, once it enters the TS, it'll seemingly slow down to the normal speed for those also in the TS.
The reason I bring up how magic probably means the normal logic with temporal distortions doesn't apply is because this power adjustment applies to any form of energy entering/exiting the field such as light. If you are inside a Temporal Sludge the outside should look approximately 3x brighter and significantly bluer while to an outside observer you would look approximately three times dimmer and significantly redder.