Register Guidelines E-Books Search Today's Posts Mark Forums Read

Go Back   MobileRead Forums > E-Book Readers > Kobo Reader

Notices

View Poll Results: Does the kobo forma light flicker cause you eye strain?
yes 9 14.29%
no 54 85.71%
Voters: 63. You may not vote on this poll

Reply
 
Thread Tools Search this Thread
Old 01-10-2020, 01:01 AM   #76
Tokei
Member
Tokei ought to be getting tired of karma fortunes by now.Tokei ought to be getting tired of karma fortunes by now.Tokei ought to be getting tired of karma fortunes by now.Tokei ought to be getting tired of karma fortunes by now.Tokei ought to be getting tired of karma fortunes by now.Tokei ought to be getting tired of karma fortunes by now.Tokei ought to be getting tired of karma fortunes by now.Tokei ought to be getting tired of karma fortunes by now.Tokei ought to be getting tired of karma fortunes by now.Tokei ought to be getting tired of karma fortunes by now.Tokei ought to be getting tired of karma fortunes by now.
 
Posts: 19
Karma: 2075226
Join Date: Apr 2019
Device: Kobo Forma
Quote:
Originally Posted by jackie_w View Post
How many of these "many people" have seen an actual Forma and not just the contrived videos?
I owned a Forma for several weeks and sold it due to the PWM issue. I ultimately ended up buying a Kindle Oasis 3.

The Forma was in my view better than the Oasis in many aspects. The bigger screen while weighing the same is one or that I preferred the haptics of the grippy plastic over the pointy, cold and slippery metal of the Oasis. But I was irritated, as I wrote in a post before, by the Forma’s lighting that I perceived as less calm than a non PWM-screen. I compared the device side by side in various lighting conditions (sunlight, artificial light, lights off) and also “blind-tested” with my wife and we agreed that the non-PWM screens of the Kindle PW and Oasis are easier on the eyes.

I cannot tell you if that is my mind playing tricks on me or another factor that has nothing to do with PWM. But in the end, I didnt care because it is my own subjective perception that counts in the end when making a buying decision.

So my recommendation to all who think about the Forma is to try it out, compare it and trust your own perception and opinion. You like it? Keep it. Dont like it for whatever reason? Sell it and get a different one.
Tokei is offline   Reply With Quote
Old 01-10-2020, 05:45 AM   #77
koboyedi
Member
koboyedi could sell banana peel slippers to a Deveel.koboyedi could sell banana peel slippers to a Deveel.koboyedi could sell banana peel slippers to a Deveel.koboyedi could sell banana peel slippers to a Deveel.koboyedi could sell banana peel slippers to a Deveel.koboyedi could sell banana peel slippers to a Deveel.koboyedi could sell banana peel slippers to a Deveel.koboyedi could sell banana peel slippers to a Deveel.koboyedi could sell banana peel slippers to a Deveel.koboyedi could sell banana peel slippers to a Deveel.koboyedi could sell banana peel slippers to a Deveel.
 
Posts: 23
Karma: 3488
Join Date: Jan 2020
Device: kobo forma
I've now ordered a Libra (gets here after the weekend) and will then compare it with the Forma. I'm really curious how these two compare hands on side by side, since I'm currently super-biased in favour of the Libra while the spec sheets favour the Forma.
koboyedi is offline   Reply With Quote
Old 01-12-2020, 04:32 PM   #78
filmo
Wizard
filmo ought to be getting tired of karma fortunes by now.filmo ought to be getting tired of karma fortunes by now.filmo ought to be getting tired of karma fortunes by now.filmo ought to be getting tired of karma fortunes by now.filmo ought to be getting tired of karma fortunes by now.filmo ought to be getting tired of karma fortunes by now.filmo ought to be getting tired of karma fortunes by now.filmo ought to be getting tired of karma fortunes by now.filmo ought to be getting tired of karma fortunes by now.filmo ought to be getting tired of karma fortunes by now.filmo ought to be getting tired of karma fortunes by now.
 
Posts: 1,324
Karma: 1077205
Join Date: Jun 2011
Device: Kobo Touch, Sony T1, Kobo Mini
I was a motion picture cameraman. Film speed standard was 24 frames per second. That isn't fast enough to eliminate flicker so each frame was projected twice by a butterfly shutter. High speed 16mm motion picture camera with pull down claw film advance and registration pin holding film during exposure were limited to 400 fps but using rotating glass shutter much faster frame rate is possible. I,000 fps +, because film didn't need to stop for each frame exposure.
filmo is offline   Reply With Quote
Old 01-13-2020, 02:03 PM   #79
JSWolf
Resident Curmudgeon
JSWolf ought to be getting tired of karma fortunes by now.JSWolf ought to be getting tired of karma fortunes by now.JSWolf ought to be getting tired of karma fortunes by now.JSWolf ought to be getting tired of karma fortunes by now.JSWolf ought to be getting tired of karma fortunes by now.JSWolf ought to be getting tired of karma fortunes by now.JSWolf ought to be getting tired of karma fortunes by now.JSWolf ought to be getting tired of karma fortunes by now.JSWolf ought to be getting tired of karma fortunes by now.JSWolf ought to be getting tired of karma fortunes by now.JSWolf ought to be getting tired of karma fortunes by now.
 
JSWolf's Avatar
 
Posts: 56,046
Karma: 51740230
Join Date: Nov 2006
Location: Roslindale, Massachusetts
Device: Kobo Aura H2O, Sony PRS-650, Sony PRS-T1, nook STR, iPad 4, iPhone 5
How many of you who are complaining about the flicker has seen the flickrer on an actual Forma? Videos do not count.
JSWolf is online now   Reply With Quote
Old 01-13-2020, 05:16 PM   #80
koboyedi
Member
koboyedi could sell banana peel slippers to a Deveel.koboyedi could sell banana peel slippers to a Deveel.koboyedi could sell banana peel slippers to a Deveel.koboyedi could sell banana peel slippers to a Deveel.koboyedi could sell banana peel slippers to a Deveel.koboyedi could sell banana peel slippers to a Deveel.koboyedi could sell banana peel slippers to a Deveel.koboyedi could sell banana peel slippers to a Deveel.koboyedi could sell banana peel slippers to a Deveel.koboyedi could sell banana peel slippers to a Deveel.koboyedi could sell banana peel slippers to a Deveel.
 
Posts: 23
Karma: 3488
Join Date: Jan 2020
Device: kobo forma
Quote:
Originally Posted by JSWolf View Post
How many of you who are complaining about the flicker has seen the flickrer on an actual Forma? Videos do not count.
You can't see it with the naked eye but that's not the point. The point is I want a device that it as less stressful to the eyes as possible and with PWM it doesn't matter if you can see the flickering.

That's what happens when you sit in front of a computer screen and read for hours, it also doesn't flicker 'visibly' but it's still there and messes with your eyes as you read long text.


This is how your eyes normally read letters on a continuously lit display. It's one smooth motion.


This is how your eyes read letters with PWM LEDs. In staccato, the opposite of smooth.


Which display seems less stressful to your eyes?

Last edited by koboyedi; 01-13-2020 at 05:19 PM.
koboyedi is offline   Reply With Quote
Old 01-13-2020, 05:23 PM   #81
JSWolf
Resident Curmudgeon
JSWolf ought to be getting tired of karma fortunes by now.JSWolf ought to be getting tired of karma fortunes by now.JSWolf ought to be getting tired of karma fortunes by now.JSWolf ought to be getting tired of karma fortunes by now.JSWolf ought to be getting tired of karma fortunes by now.JSWolf ought to be getting tired of karma fortunes by now.JSWolf ought to be getting tired of karma fortunes by now.JSWolf ought to be getting tired of karma fortunes by now.JSWolf ought to be getting tired of karma fortunes by now.JSWolf ought to be getting tired of karma fortunes by now.JSWolf ought to be getting tired of karma fortunes by now.
 
JSWolf's Avatar
 
Posts: 56,046
Karma: 51740230
Join Date: Nov 2006
Location: Roslindale, Massachusetts
Device: Kobo Aura H2O, Sony PRS-650, Sony PRS-T1, nook STR, iPad 4, iPhone 5
Quote:
Originally Posted by koboyedi View Post
You can't see it with the naked eye but that's not the point. The point is I want a device that it as less stressful to the eyes as possible and with PWM it doesn't matter if you can see the flickering.

That's what happens when you sit in front of a computer screen and read for hours, it also doesn't flicker 'visibly' but it's still there and messes with your eyes as you read long text.


This is how your eyes normally read letters on a continuously lit display. It's one smooth motion.


This is how your eyes read letters with PWM LEDs. In staccato, the opposite of smooth.


Which display seems less stressful to your eyes?
Have you used a Forma and gotten eye strain? What I want to know is PVM a real problem or is a big deal being made by what some perceive as a problem that's really not a problem.
JSWolf is online now   Reply With Quote
Old 01-13-2020, 05:45 PM   #82
koboyedi
Member
koboyedi could sell banana peel slippers to a Deveel.koboyedi could sell banana peel slippers to a Deveel.koboyedi could sell banana peel slippers to a Deveel.koboyedi could sell banana peel slippers to a Deveel.koboyedi could sell banana peel slippers to a Deveel.koboyedi could sell banana peel slippers to a Deveel.koboyedi could sell banana peel slippers to a Deveel.koboyedi could sell banana peel slippers to a Deveel.koboyedi could sell banana peel slippers to a Deveel.koboyedi could sell banana peel slippers to a Deveel.koboyedi could sell banana peel slippers to a Deveel.
 
Posts: 23
Karma: 3488
Join Date: Jan 2020
Device: kobo forma
Sorry, I've only used mine briefly since it's currently on route to be replaced because of other screen lighting issues.
koboyedi is offline   Reply With Quote
Old 01-13-2020, 05:50 PM   #83
JSWolf
Resident Curmudgeon
JSWolf ought to be getting tired of karma fortunes by now.JSWolf ought to be getting tired of karma fortunes by now.JSWolf ought to be getting tired of karma fortunes by now.JSWolf ought to be getting tired of karma fortunes by now.JSWolf ought to be getting tired of karma fortunes by now.JSWolf ought to be getting tired of karma fortunes by now.JSWolf ought to be getting tired of karma fortunes by now.JSWolf ought to be getting tired of karma fortunes by now.JSWolf ought to be getting tired of karma fortunes by now.JSWolf ought to be getting tired of karma fortunes by now.JSWolf ought to be getting tired of karma fortunes by now.
 
JSWolf's Avatar
 
Posts: 56,046
Karma: 51740230
Join Date: Nov 2006
Location: Roslindale, Massachusetts
Device: Kobo Aura H2O, Sony PRS-650, Sony PRS-T1, nook STR, iPad 4, iPhone 5
Quote:
Originally Posted by koboyedi View Post
Sorry, I've only used mine briefly since it's currently on route to be replaced because of other screen lighting issues.
When you do get your replacement Forma and you've used it enough, please let us know if the "flicker" is a problem. I want hard facts, not what some may think without really knowing.

I have not read of anyone saying they get eyestrain from using a Forma. If there is no perceived flicker, there's no eyestrain (going from what I've not read). If there was eyestrain with a Forma, I would have expected to read about it on MR by now.

The way I'm reading it, some are reading about PVM and thinking they may be seeing flicker when there is none. If they had never heard of PVM, they would not perceive any flicker.
JSWolf is online now   Reply With Quote
Old 01-13-2020, 05:54 PM   #84
koboyedi
Member
koboyedi could sell banana peel slippers to a Deveel.koboyedi could sell banana peel slippers to a Deveel.koboyedi could sell banana peel slippers to a Deveel.koboyedi could sell banana peel slippers to a Deveel.koboyedi could sell banana peel slippers to a Deveel.koboyedi could sell banana peel slippers to a Deveel.koboyedi could sell banana peel slippers to a Deveel.koboyedi could sell banana peel slippers to a Deveel.koboyedi could sell banana peel slippers to a Deveel.koboyedi could sell banana peel slippers to a Deveel.koboyedi could sell banana peel slippers to a Deveel.
 
Posts: 23
Karma: 3488
Join Date: Jan 2020
Device: kobo forma
Deal
koboyedi is offline   Reply With Quote
Old 01-13-2020, 05:55 PM   #85
JSWolf
Resident Curmudgeon
JSWolf ought to be getting tired of karma fortunes by now.JSWolf ought to be getting tired of karma fortunes by now.JSWolf ought to be getting tired of karma fortunes by now.JSWolf ought to be getting tired of karma fortunes by now.JSWolf ought to be getting tired of karma fortunes by now.JSWolf ought to be getting tired of karma fortunes by now.JSWolf ought to be getting tired of karma fortunes by now.JSWolf ought to be getting tired of karma fortunes by now.JSWolf ought to be getting tired of karma fortunes by now.JSWolf ought to be getting tired of karma fortunes by now.JSWolf ought to be getting tired of karma fortunes by now.
 
JSWolf's Avatar
 
Posts: 56,046
Karma: 51740230
Join Date: Nov 2006
Location: Roslindale, Massachusetts
Device: Kobo Aura H2O, Sony PRS-650, Sony PRS-T1, nook STR, iPad 4, iPhone 5
Quote:
Originally Posted by koboyedi View Post
Deal
Thank you. It will be good to have some hard data.
JSWolf is online now   Reply With Quote
Old 01-13-2020, 06:17 PM   #86
DNSB
Bibliophagist
DNSB ought to be getting tired of karma fortunes by now.DNSB ought to be getting tired of karma fortunes by now.DNSB ought to be getting tired of karma fortunes by now.DNSB ought to be getting tired of karma fortunes by now.DNSB ought to be getting tired of karma fortunes by now.DNSB ought to be getting tired of karma fortunes by now.DNSB ought to be getting tired of karma fortunes by now.DNSB ought to be getting tired of karma fortunes by now.DNSB ought to be getting tired of karma fortunes by now.DNSB ought to be getting tired of karma fortunes by now.DNSB ought to be getting tired of karma fortunes by now.
 
DNSB's Avatar
 
Posts: 6,964
Karma: 32272951
Join Date: Jul 2010
Location: Vancouver
Device: Kobo Forma, Clara HD, Nexus 7 HD, iPad Pro, Tolino epos
Quote:
Originally Posted by JSWolf View Post
Have you used a Forma and gotten eye strain? What I want to know is PVM a real problem or is a big deal being made by what some perceive as a problem that's really not a problem.
I haven't noted eyestrain from reading on my Forma nor have I noticed flickering. Given that the Forma uses a 1kHz cycle and even in saccade, no one has reliably claimed to be able to notice flicker with the naked eye when a >400Hz rate was used, I'm not worried about PWM being a problem.
DNSB is offline   Reply With Quote
Old 01-13-2020, 06:26 PM   #87
Maritimer555
Member
Maritimer555 began at the beginning.
 
Posts: 17
Karma: 10
Join Date: Oct 2014
Location: Nova Scotia
Device: Aura One Kobo Glo, Kobo Touch, Sony T1 and prs 350
Hi All,
I picked up the Forma at Coles before Christmas. I have been reading on it everyday since mid Dec. my previous reader was the Aura One. I have noticed zero screen flickering issue nor have I noticed any eye strain vs the Aura One.
Maritimer555 is offline   Reply With Quote
Old 01-13-2020, 06:40 PM   #88
JSWolf
Resident Curmudgeon
JSWolf ought to be getting tired of karma fortunes by now.JSWolf ought to be getting tired of karma fortunes by now.JSWolf ought to be getting tired of karma fortunes by now.JSWolf ought to be getting tired of karma fortunes by now.JSWolf ought to be getting tired of karma fortunes by now.JSWolf ought to be getting tired of karma fortunes by now.JSWolf ought to be getting tired of karma fortunes by now.JSWolf ought to be getting tired of karma fortunes by now.JSWolf ought to be getting tired of karma fortunes by now.JSWolf ought to be getting tired of karma fortunes by now.JSWolf ought to be getting tired of karma fortunes by now.
 
JSWolf's Avatar
 
Posts: 56,046
Karma: 51740230
Join Date: Nov 2006
Location: Roslindale, Massachusetts
Device: Kobo Aura H2O, Sony PRS-650, Sony PRS-T1, nook STR, iPad 4, iPhone 5
Quote:
Originally Posted by DNSB View Post
I haven't noted eyestrain from reading on my Forma nor have I noticed flickering. Given that the Forma uses a 1kHz cycle and even in saccade, no one has reliably claimed to be able to notice flicker with the naked eye when a >400Hz rate was used, I'm not worried about PWM being a problem.
Quote:
Originally Posted by Maritimer555 View Post
Hi All,
I picked up the Forma at Coles before Christmas. I have been reading on it everyday since mid Dec. my previous reader was the Aura One. I have noticed zero screen flickering issue nor have I noticed any eye strain vs the Aura One.
Thank you both for hard data.
JSWolf is online now   Reply With Quote
Old 01-13-2020, 06:40 PM   #89
NiLuJe
BLAM!
NiLuJe ought to be getting tired of karma fortunes by now.NiLuJe ought to be getting tired of karma fortunes by now.NiLuJe ought to be getting tired of karma fortunes by now.NiLuJe ought to be getting tired of karma fortunes by now.NiLuJe ought to be getting tired of karma fortunes by now.NiLuJe ought to be getting tired of karma fortunes by now.NiLuJe ought to be getting tired of karma fortunes by now.NiLuJe ought to be getting tired of karma fortunes by now.NiLuJe ought to be getting tired of karma fortunes by now.NiLuJe ought to be getting tired of karma fortunes by now.NiLuJe ought to be getting tired of karma fortunes by now.
 
NiLuJe's Avatar
 
Posts: 9,992
Karma: 17701112
Join Date: Jun 2010
Location: Paris, France
Device: Kindle 2i, 3g, 4, 5w, (PW) & PW2; Kobo H2O & Forma
FWIW, I'm sitting in front of a (rather large, 32") monitor with a rather "scary" barely above 300Hz PWM frequency, and I'm still alive.

And, no, I don't notice it with the naked (well, myopic & astigmatic ;p) eye. It's readily visible through any half-decent phone camera, as it is on the Forma. Where it also doesn't bother me one bit.

(And neither did I just after switching from my old, no PWM monitor).

Last edited by NiLuJe; 01-13-2020 at 06:48 PM.
NiLuJe is offline   Reply With Quote
Old 01-13-2020, 08:39 PM   #90
davidfor
Grand Sorcerer
davidfor ought to be getting tired of karma fortunes by now.davidfor ought to be getting tired of karma fortunes by now.davidfor ought to be getting tired of karma fortunes by now.davidfor ought to be getting tired of karma fortunes by now.davidfor ought to be getting tired of karma fortunes by now.davidfor ought to be getting tired of karma fortunes by now.davidfor ought to be getting tired of karma fortunes by now.davidfor ought to be getting tired of karma fortunes by now.davidfor ought to be getting tired of karma fortunes by now.davidfor ought to be getting tired of karma fortunes by now.davidfor ought to be getting tired of karma fortunes by now.
 
Posts: 18,614
Karma: 30757200
Join Date: Jul 2011
Location: Sydney, Australia
Device: Kobo:Touch,Glo, AuraH2O, GloHD,AuraONE, ClaraHD, Libra H2O; tolinoepos
Quote:
Originally Posted by NiLuJe View Post
FWIW, I'm sitting in front of a (rather large, 32") monitor with a rather "scary" barely above 300Hz PWM frequency, and I'm still alive.

And, no, I don't notice it with the naked (well, myopic & astigmatic ;p) eye. It's readily visible through any half-decent phone camera, as it is on the Forma. Where it also doesn't bother me one bit.

(And neither did I just after switching from my old, no PWM monitor).
My wife suffers from severe and frequent migraines. And has some other eye issues. Flashing can trigger her migraines. If anyone was going to be affected by this, I would expect she would. But, she has been has been using the Forma for the last year or so without any issues.
davidfor is offline   Reply With Quote
Reply

Thread Tools Search this Thread
Search this Thread:

Advanced Search

Forum Jump

Similar Threads
Thread Thread Starter Forum Replies Last Post
screen flickering and pixelated ejseeks Kobo Reader 4 01-10-2017 07:52 PM
KT Screen Flickering Fahd Kindle Developer's Corner 11 05-29-2013 09:08 AM
Screen flickering/blinking islandmixed Amazon Kindle 2 12-22-2012 09:28 PM
Flickering Screen? luqmaninbmore Nook Color & Nook Tablet 2 01-11-2011 12:47 PM
Screen flickering and color blotches? ozero Nook Color & Nook Tablet 12 12-06-2010 03:19 PM


All times are GMT -4. The time now is 05:19 PM.


MobileRead.com is a privately owned, operated and funded community.