This is likely due to the way the lens is being held due to muscle memory from using the 90D! The Digital Wide Field has different glass and coatings than the classic lenses and also has a different optical design, so it takes slight adjustments to get used to it. Try tilting the lens slightly to find the right sweet spot to give you a glare free view and you will see a significant difference. Alternatively, you can also have the slit lamp illumination tower at a slight angle if you prefer to direct the reflections in a different direction. Lastly, the Digital Wide Field has a shorter working distance than the classic lenses, so make sure you get closer towards the cornea (~5 mm) to get the full field.