Inky wHAT ghosting and lighter red than expected

Hi everybody…long time listener, first time caller.

I’ve been playing around with our fancy new red Inky wHAT and am having some disappointing results.

I wanted to use the wHAT to show some business metrics, and have adapted the name badge example to show how many orders we have taken. Right now it is flipping between our two businesses every 5 minutes, and as it does so, we are getting some ghosting and lighter than expected coloration.

The pics below should speak for themselves, but I will also note that when we first boot the Pi, the red is much darker. It seems to become lighter as we go.

More images since the forum will only allow me to post 1 image at a time.

And here’s an image running the name badge example after the first two.

I have the same problem.
Ghosting from previous images in my case text.
I have tried over writing the whole image with a white rectangle between updates but this doesn’t help.
In one are I am writing white text onto a red background. The red gets lighter ever update and previous text characters burn in as darker regions.
Is this a fault? … or am I doing something wrong?

I know it won’t help but maybe Pimoroni will notice : I have the same problem, the red ink is very light and shows a lot of ghosting.
I’ve tried to run the “clean.py” sample and that almost cleared the ghosting, but the red is still not what it should be.

FYI, after running the “clean.py” sample for about 200 times, the ghosting is gone. But the red is still not as red as it should/could be.

Hi I am having the same issue with the Inky Phat, it is only a mono version so no colour but I still get ghosting and half images. I thought it may be a power issue but after trying various well rated (current) power supplies I still get the same issues. most of the time it works ok and then goes wrong when you are showing someone how cool it is! I have it switching between the calendar, name badge and the weather. It seems to be better after a reboot so I have the pi reboot every hour using cron.
My wife’s Kindle doesn’t have this problem!

Seeing the same issue here, and I’ve a 4.2" Waveshare/Goodisplay to compare it to (left, Inky wHAT on the right):

This was taken immediately after updating both of them, and the Inky wHAT is definitely a lighter red. Like with the other posters, the Inky wHAT seems to fade to a coral color within a few hours, whereas the Waveshare/Goodisplay unit retains its color.

Is this a software issue (LUTs?) or are these panels just not as red as others?

And here’s it looking much too coral, especially in contrast to the other display:

I have this too. Brand new screen and the red looks faded with lots of ghosting :(

It looks like an update was pushed to the inky library last week that tweaks how reds are displayed. I pulled out my badge to try it out. It’s not available through the installer yet, but you can remove the current version 0.0.4 and install the new code directly with git clone https://github.com/pimoroni/inky.git; cd inky; sudo ./uninstall.sh; sudo ./install.sh

The new red color is darker than the competing display! There is still ghosting with repeated changes. I don’t think it’s still getting lighter with repeated changes, but I’ve only tested a handful of changes, not every five minutes all day like @chicagoedist.

A regular three-pass cleaning cycle run with ./clean.py -t what -c red appears to remove the ghosting, not two hundred passes as @yannick had to do. (One pass alone doesn’t, but two passes with ./clean.py -t what -c red -n 2 gets pretty close!)

I’ll have to leave it alone for a bit to see if it fades much over time, but I’m looking forward to this change hitting the installer!

24 hours later and the color’s really held up! Competitor display on the left, Inky wHAT on the right, same as my picture a few posts ago, both 24h after display updates.

👍