Hi, first time here, I have a Convoy C8 UV 365nm and have tried using it to illuminate tonic water in slow motion at 1920 fps, the flicker is very pronounced, I would say every second or so when played back at 30 fps. Is this normal? I also have some cheap LED fairy lights that flicker sometimes but not others when changing colour, it seems random, e.g. red might flicker one time but not again when cycling through the colours.
Sure it’s not an artifact of the framerate conversion?
Dunno about the C8 in question, but if it was pwmed, it’d show up a lot more often and regularly.
Try highest mode instead?
Thank you both for the quick responses;
Lightbringer - I don’t think it is, as it’s not consistent across light sources, the fairy lights flickered sometimes but not others, there was no flicker from the LED down lights in my kitchen and another visible spectrum LED flashlight powered by a single 18650 did not flicker at all. I have two of the UV C8s and both have this flicker.
freeme - How do I do that? There is just one button, no instructions came with them.
Not sure what the UV version uses in it’s driver as far as PWM.
The normal C8 with the Guppy driver I measured from several years ago, has a 16.5KHz PWM in medium brightness mode.
If you can, try changing the shutter speed to see if that changes the flicker rate.
This might give you a clue as to what’s happening.
I suspect the UV version may have a unique PWM to keep the LED happy.
All the Best,
Jeff
You might also try lighting up a spinning fan blade with a drop of UV paint on it.
The faster the fan - the better. Computer cooling fans - CPU etc are good for this.
Then try it with a few different lights.
Not sure this will tell you anything, but it might be interesting to try.
Thank you Jeff, I’ve had a look around the web and can’t find which driver it uses. Initially I said that the flashing was about once per second at 1920fps played at 30fps, but after reviewing the footage again, it is a lot more, between 5 to 10 flashes per second.
I’m using a Huawei P40 Pro and in it’s slow motion modes you’re very limited on what you can alter, pretty much the frame rate.