Wondfo experts please help

The last 2 days i have gotten this VERY VERY light line where the test line should be. It is far too faint for me to be considering it a positive test so im not asking if you think it is positive i am wondering if all of the tests have this and i just havent noticed? Its almost impossible to catch with the camera and i spent like 20 mins trying to tweak to make it clearer since it is more visible in person but i am just curious bc as i said i wont be walking around thinking i am pregnant based on a line this light but i will probably not use these tests anymore if they always have it. I can see it at the 5mm but as always it became more visible by 10 mm. Please let me know if this is common for these tests or maybe i got a bad batch. Thank you! These are all the same 1 test from today the first pic is at 5mm the rest vary in time from when i took it to the 20 mins i spent trying to capture it to show you all lol