Such thing as an evap line?

[Hellobonjourhallo]

Is there such thing as an evap line on a lateral flow test?

I've been feeling a bit down yesterday / today, so I took a test this morning (work request) nothing came up Immediately but I went back after about 25 - 30 mins and there was a line there but with no colour at all.

Done another this evening and the same thing again... barely visible until around 25 mins then a line with no colour.

Pics attached hopefully..

Looks like a positive to me

Do another today. Friends have had faint grey lines as well as my daughter. Turned pink pretty quickly on the next tests

That's positive. Evap lines are never clean and solid.

Possibly - it’s the lack of colour that’s the key but (same when you POAS) a faint line with the intended colour is a positive result.

A greyish or colourless line suggests a failed test and I would do it again in a few hours

Thank you

woke up feeling like I have more of a cold today with a slight cough, completely negative today though. Bizarre!

The instructions say that's positive if it's within the timeframe, but my son often gets grey lines on one brand of tests. Always negative when cross checked with another brand or PCR back when that was an option.