Have you ever wondered whether it was possible to change the contrast ratio of your Sony Reader screen? Well, now it seems you can, though the procedure is not for the faint of heart. Igorsk pointed us (http://www.mobileread.com/forums/showthread.php?t=10756) to this (very interesting) website (http://www.msh-tools.com/ebook/contrast.html) explaining how you can adjust the screen ratio by changing the position of a specific resistor (yes, in other words, you'd have to disassemble the hardware). Whether the adjustment is for the better or worse, I don't know. Make sure to compare the screenshots.

It does not seem difference...? The contrast ratio is really an issue when reading PDFs

Yikes, well I am not going there <G>

I will not try that. My screen is good as it is and who knows what it does to the lifetime of the screen.

I'd think it probably wouldn't affect display life, actually, or they'd have the rascal hard-wired instead of a trim pot. The fact that the trim pot is there suggests (to me, at least) that there is an assembly step where somebody tweaks the thing to dial it into some sort of range.

That's a fairly common approach to such things -- if you've torn apart much in the way of e-devices (other than computers, and especially RF equipment, 2-way radios, etc.) you'll recall seeing such trim pots in them, usually with a dollop of hot-glue to physically hold them fixed once they've been set.

In fact, the absence of said glue-dollop makes me think that the pot's actual setting isn't all that critical, but that's just a guess.

I'd think that if your contrast doesn't bother you, don't mess with it. And if it does and you aren't worried about opening the case up, go for it.

Of course that's a pretty brutally obvious summation, isn't it? :mad:

All of this is just my opinion, of course, so salt to taste.

On my work we have instruments that use a monochrome LCD. That display has also pot but if you crank it up to high pixels will start to die. Of course it's a different technology but I don't want to take the risk. Also on the picture with the more contrast the ghosting is very noticeable. I don't know if there is a middle way but I don't like how it looks on the picture.

Mine doesn't ghost as much as my wife's. I'm wondering if I should open hers and have a go trying to set it to look like mine (if possible).

On my work we have instruments that use a monochrome LCD. That display has also pot but if you crank it up to high pixels will start to die. Of course it's a different technology but I don't want to take the risk.I understand completely, DiabloNL, further, I wouldn't want to encourage anyone to take any risk they weren't comfortable with. Shucks, just opening the case is a risk most folks wouldn't want to take, and I wouldn't give them a hard time over that either. :beam:

omg, this is fn awesome. wait till I write my display driver to fix the ghosting on high-contrast. ahh.... someone stole my eyeglass screwdrivers. I'm going to the store

ok, screwdrivers found.

hm.. i have trouble figuring out if this does anything that rasterfarian doesn't already do. Blacks don't really seem much darker (perhaps a little), just thicker (identical to a dilate). One issue seems to be that the white background turns darker too. The overall effect is more ghosting, thicker text, and about the same real contrast (but maybe a bit better).

My initial theory was that the black-white transition makes things very black and they don't go white again. Hence, tweaking the display driver (with more refreshes) may help. BUT, I then tried using the menu system. In the menu system, you can move the chevron causing a screen refresh without a black-white transition. If you dial up the resistor and move the chevron, the chevron appears a little darker than it was before (and than the border). But then if you keep it moving the chevron, the whole screen turns very gray even though it never went black! Restoring the resistor then moving the chevron does not make the screen white again until you do do a black-white transition.

After some more testing, it seems that a 1/8-turn counterclockwise (resistor is at 10 o-clock) improves the display a little bit without noticeable side-effects. In fact, the amount of ghosting does not seem to change at all, white doesn't turn gray, and black does become somewhat blacker. I enjoy the effect, but it's not worth it for someone who isn't the type to have already tried unscrewing the Reader (and it's only useful for PDFs).

In conclusion, I can't figure out what exactly this resistor is doing to the display or how the eInk actually functions. It seems that the resistor changes the balance between black and white. If black is negative electric field and white is positive, this perhaps change the bias or the proportions of voltages used. In short, its main function does not seem to be to change the contrast per-se.

Whatever its main function, an adventurous user who does not read PDFs can turn the resistor all the way clockwise (2 o-clock) to make the ghosting almost invisible (but if you're doing it out of OCD note that it doesn't go away 101%) and a user who does read PDFs may turn it a little counter-clockwise for a bit better legibility

Nice analysis, Alex_d. :yes:

I would throw out the slight caution to anyone who would like to try this that their resistors might not be set the same as your's initially, so they'll need to adjust what they do to them a bit accordingly. :shrug:

I'd also point out to anyone who wants to open the case that the magnets in the case are going to make putting the screws near them back in their holes a bit of a challenge. :huh:

yeah, good point about the resistor. I should have said that turning it _may improve contrast if it hasn't been dialed up (eg JSWolf's wife's contrast is probably already as high as it'll go) but it may also improve it by a rather considerable amount if it's been dialed low. Vice-versa for ghosting.

Regarding my own Reader, after so much tweaking yesterday I began to suffer from multiple-choice indecision syndrome. I have to say that when I turned it on today not thinking about what I'd done the day before, I was quite pleasantly surprised. The readability and aesthetitcs were very noticeably improved. But, again, your mileage will definately vary and don't expect anything huge. Also, there was indeed more ghosting but that doesn't bother me much.

P.S. I didn't have much trouble with the magnet. Another point for someone who'd like to try this: the trick is that after you take out all the screws you can find (one on the back, two on the bottom, two under the SD lid), you have to pull the plastic sides apart to reveal more screws.

Nice analysis, Alex_d. :yes:

I would throw out the slight caution to anyone who would like to try this that their resistors might not be set the same as your's initially, so they'll need to adjust what they do to them a bit accordingly. :shrug:

I'd also point out to anyone who wants to open the case that the magnets in the case are going to make putting the screws near them back in their holes a bit of a challenge. :huh:

You opened it NatCh?

You opened it NatCh?Quite some time ago, diabloNL ... back in ... October, maybe? :nice:

Quite some time ago, diabloNL ... back in ... October, maybe? :nice:


Just to take a peek or has it got blue LED's all over the thing? :p

:laugh4: "blue LED's all over"! That's hysterical! :laugh4:

No, I didn't add blue LEDs, I actually was hoping to get a part number off the stinkin' battery at the time.

Now that you mention it though, I did recently purchase a lot of 100 self-flashing RGB LEDs ....

Those are for a specific project, though: I have a small box that I put 16 single color self-flashing LEDs on about 7~8 years ago (like the computer displays in old 1970s movies, you know -- except mine all blink separately in a psuedo-random pattern created by the duty cycle variances of the individual LEDs), and I want to make it bigger and better, of course.

Unfortunately, I don't really have a place to work on it right now (in fact, I opened the Reader on my desk at work one day), and we're getting ready to move at the end of July, so I'm not starting projects that I can't finish in an hour or so these days. On the other hand, we're getting ready to move, and I hope to have enough space to set projects up and leave them set up 'til I complete them. :smiley:

I tried this out, with the following observations:

This resistor seems to be involved with ghosting control. Too far one way, and the menu background gets darker with each pointer movement--that is, "white" voltages start to darken the display pixels. Moving the pointer then leaves white ghosts on an increasingly black background. Moving it the other way leaves dark ghosts of the pointer, with the menu background staying white. That is, the inverted "negative" image does not seem to be clearing pixels.

The best setting seems to be just at the point where the cursor leaves no ghost, or just the faintest black ghost. It may take 10 or more pointer moves to see the white ghost, as the background darkens just a bit on each move. This setting does not seem to be too sensitive in terms of resistor position, 1/12 turn is about the threshold for a noticeable difference.

I found that the optimal setting was 1/4 turn counterclockwise from the factory setting. This did result in improved legibility, but noticeably more residual image when the reader was turned off.

BTW, I also took the opportunity to remove the chrome from the top surfaces of the side strips, and paint these black. That chrome is ridiculously bright compared to the black reader and dark display with my visual problems. Scraped it off with a razor blade, stone-age technique but none of the etchants I had would touch it.

:laugh4: "blue LED's all over"! That's hysterical! :laugh4:

No, I didn't add blue LEDs, I actually was hoping to get a part number off the stinkin' battery at the time.

Now that you mention it though, I did recently purchase a lot of 100 self-flashing RGB LEDs ....

Those are for a specific project, though: I have a small box that I put 16 single color self-flashing LEDs on about 7~8 years ago (like the computer displays in old 1970s movies, you know -- except mine all blink separately in a psuedo-random pattern created by the duty cycle variances of the individual LEDs), and I want to make it bigger and better, of course.


That's really cool. Don't forget making some pictures when you start on this project. ;)

Speaking of pictures. dstampe, do you have a picture showing what you've done? :shy:

That's really cool. Don't forget making some pictures when you start on this project. ;)That'll be a while, but since you're interested, here's a short clip of the one I already have (it's in some goofy format that my Trēo uses :shrug: )

No, I didn't add blue LEDs, I actually was hoping to get a part number off the stinkin' battery at the time.
:smiley:

Is there a replacement battery available?
Is the one in there soldered in?

My battery life stinks and the unit is out of warranty :angry:

Please correct me if I'm wrong, but I thought that the warranty on the Reader was a year. No Reader is a year old yet, is it? It was only launched in - what? October?

I thought the warranty was a year, but I'd have to go look. :shrug:

@LateMarch: The battery has a connector -- it's not soldiered in -- but there's no part number visible on the thing, so while there may be (probably is) a replacement battery available somewhere we don't know what to look for. :sad:

That'll be a while, but since you're interested, here's a short clip of the one I already have (it's in some goofy format that my Trēo uses :shrug: )


That's so..so..well..spacy. :D I like it!


BTW there is a part number on the battery. Let me get it for you.

EDIT: Here it is. (http://www.mobileread.com/forums/showpost.php?p=67638&postcount=14)

That's so..so..well..spacy. :D I like it!Glad you find it amusing. They're really not too hard to do, the biggest hurdle is the cost of the materials, mostly the LEDs. That one all the LED's are connected in parallel, so the power supply has to be pretty hefty. One of the things I need to work out with the bigger one is just how many I can put in series with which power supply, so I can get away from supplying some ridiculous amount of current -- I know how to work it out, and have the tools, but no place to actually do the work at present. :sad:

Glad you find it amusing. They're really not too hard to do, the biggest hurdle is the cost of the materials, mostly the LEDs. That one all the LED's are connected in parallel, so the power supply has to be pretty hefty. One of the things I need to work out with the bigger one is just how many I can put in series with which power supply, so I can get away from supplying some ridiculous amount of current -- I know how to work it out, and have the tools, but no place to actually do the work at present. :sad:

I think the best is to make a combination of series and parallel. In that way you can put quite a lot on a decent P/S.

That's more or less where I figure I'll end up, but I have to nail down the more and less. :wink: