I don't have much soldering experience. I soldered 5 level converters, they seem to work and look about the same as this STM32 as I soldered.
However, after a closer look I see not all pens 'shine' and some don't have a good form. Probably used too much soldering, because it was quite hard to determine (using too less cause nothing but heating pins which I also wanted to prevent more than needed).
How can I best test if all soldering connections are ok? I don't have any STM32 experience, so I don't know if there is a general way to do this except for writing programs/testing for each pin?
Or is it visible directly from the pictures that this will not work (I hope not).
(btw it's hard to make pics, they are all from the same STM32, the first pic shows soldering connections which are much darker than the second, the second looks more like the real thing).
Edit: I think I know what I did wrong ... since I didn't have much space the solder tip and solder tin sometimes might have touched directly, also during that the pin itself might not have been heated enough. Next time I really should make sure the tin and tip are on opposite sides of the pin.
Update: Used aceton/alcohol
I used a mixture of 50% 96% alcohol and aceton and got the following results: It seems to leave some white residue ... wondering if that is a problem.