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iPhone XS Max iPhone XS Max brightness adjustment not smooth transition...

Mbman81

macrumors member
Original poster
Jun 5, 2010
92
2
When adjusting brightness (either manually via slider or auto brightness adjustment) around ~20% there is a big jump up/down in brightness. It's not a smooth transition, visually noticeable and very distracting. Looks like a flash (when it jumps up) or a idle phone screen dim (when jumps down).

To test: Just slide the brightness bar really slowly from about 30% to 10%. You will hit a point where brightness jumps dramatically instead of smoothly. You can go the other way to from 10% to 30%, too. Should see brightness jump/dim somewhere around 18-20%

Edit: Just realized you need to have Night Shift on and True Tone or it doesn’t do do it. Make sure those on.

Both my phones do it. Anyone else experience this? Can I ask a few others to test this?
 
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Mbman81

macrumors member
Original poster
Jun 5, 2010
92
2
Doh. Surprised if both mine and wife’s do it and not others around here. Anyone else try it out?
[doublepost=1538452564][/doublepost]Second note! Just realized you need to have Night Shift on and True Tone or it doesn’t do do it. Make sure those on.

Adding to main post.
 

Mbman81

macrumors member
Original poster
Jun 5, 2010
92
2
Anyone else mind testing? Might run to the Apple Store and test out too. Will report back if I get there.
 

JD92

macrumors 6502a
Apr 14, 2005
934
31
Anyone else mind testing? Might run to the Apple Store and test out too. Will report back if I get there.

My XS Max does this. I guess it’s just the way the curve is set in the software.
 

derangedwolf

macrumors newbie
Oct 2, 2018
2
0
Anyone else mind testing? Might run to the Apple Store and test out too. Will report back if I get there.
I can confirm mine does it, I got mine launch day and when the brightness would reach a certain point it would jump to it quickly instead of lowering the brightness smoothly. I hope it's a software issue

Also~ Disabling True Tone stops this from happening. this leads me to believe it's a software issue because it doesn't happen without it being on and if it was hardware it would do it all the time.
 
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Mbman81

macrumors member
Original poster
Jun 5, 2010
92
2
Thanks for update.
FYI: I went to apple store tonight and every iPhone XS and XS Max does it. I looked at 9 phones in total all did it.
 

mppn

macrumors regular
Feb 22, 2016
226
172
Montreal, QC, Canada
Can confirm mine does it too (Xs Max)

After my tests, you need either night shift or true tone for it to happen. Both disabled is the only way to not have the bug.

I know you said it in your post but my understanding of your post was that they needed to be both enabled for the bug to happen
 

itsmilo

Suspended
Sep 15, 2016
3,985
8,709
Berlin, Germany
I noticed today during my day at the beach that I could read everything perfectly at first really bright but then it would auto adjust to something much darker however if I pulled it all the way up manually it wouldn’t get as bright as it was initially. Very strange
 

leftcoastnomad

macrumors newbie
Oct 3, 2018
12
1
Can confirm mine does it too (Xs Max)

After my tests, you need either night shift or true tone for it to happen. Both disabled is the only way to not have the bug.

I know you said it in your post but my understanding of your post was that they needed to be both enabled for the bug to happen
I think you are correct. I actually thought this might be due to a bad batch of phones and asked Apple about it. They said they hadn't heard of this and stated it was a hardware issue and replaced the phone immediately. The new one does the same exact thing. Its hard to believe that a bug like this still hasn't been fixed 2.5 months after launch? Wow. I don't ever remember Apple products being this rough when they launched.

I'm surprised more aren't complaining about this. I think if you use your phone in brighter areas its not as noticeable.
 
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