Friday, June 11, 2021

PWM, temporal dithering and headaches with newer Apple displays

iPhones

Most new smartphones use a display technology called OLED.  These displays use a technology called PWM (pulse width modulation) for dimming the display.  This creates a flicker, which while not perceptible to the eye, can cause all kinds of symptoms -- headaches, nausea, etc.  Every time I have tried the newer iPhones with OLED displays in the store, I find I immediately feel eyestrain.  This has kept me from buying one of them and I have stuck to an iPhone with the older display technology called LCD.

If you have had issues with newer phones, you might be sensitive as well.  This article sums up the problem nicely.

PWM may not be the whole issue.  There's also refresh rates (which impacts the smoothness of scrolling), addressed to some extent by ProMotion in some newer iPhones, and also temporal dithering.  More on temporal dithering below.

MacBooks

With newer MacBooks, a small, but not insignificant, number of users, including myself, have experienced really bad headaches when using them.  A few things that I did to try and mitigate the problem included turning off true tone, turning off auto brightness, and turning off dimming when running on battery.  None of these helped.

Digging deeper, I discovered that there's a feature called temporal dithering that Apple implements in order to render a larger number of colors than the display is natively capable of.  Unfortunately there is no way to turn this off using native controls in macOS.

In some of the forums, it was suggested that SwitchResX is an app that can be used to disable temporal dithering by setting the display to render millions of colors rather than billions of colors which is the default.

Another useful tool for checking various aspects of displays such as pixel inversion is the Lagom LCD monitor test pages.  Testing side by side with a Dell XPS, the M1 MacBook Air showed noticeably more flicker.

Finally, Iris is another tool attempts to get around PWM with laptops by using an app to control brightness and filtering colors in a way that makes the display experience easy on the eyes.

References

Thursday, December 10, 2020

Planning for retirement

 Placeholder for useful links for retirement planning.

Monday, April 13, 2020

Some thoughts on ZIRP/NIRP

ZIRP stands for zero interest rate policy.  NIRP stands for negative interest rate policy.  As governments and corporations are awash in debt, ZIRP and NIRP appear to have been embraced whole-heartedly by central banks.

As the federal reserve started to lower its benchmark interest rate back towards zero (it is zero as of this writing), I started to think about what this means for fixed-income investments if they decide to go from ZIRP to NIRP.

In some of the online forum discussions, folks said a drop of 0.5% in interest, e.g. from +0.25% to -0.25% is the same as, e.g., a drop from +0.5% to 0%.  To show that this is not really accurate, I presented the following example.

Lets say to have $x to invest at an interest rate of r% for a length of time t.  Then as t goes to infinity:
  • if r > 0, then the balance, x goes to infinity.
  • if r = 0, then the balance stays exactly the same at x.
  • if r < 0, then the balance x goes to 0.
In other words, with a negative interest rate, one's balance starts reducing over time and eventually goes to zero.  I hope we (the US) don't get to NIRP, but with the economy the way it is, there's no telling.  Japan and the EU have been in NIRP for a while now.  Large corporations have benefited from this.  LVMH for example had an offering of negative yielding bonds to finance its purchase of Tiffany & Co.--a case of investors actually paying LVMH to borrow their money!

The downsides of ZIRP and NIRP

Some of the down sides of ZIRP and NIRP are:
  1. It penalizes savers and those that depend on interest for fixed income.
  2. It causes people with money to speculate on assets such as stocks and real-estate. 
  3. It causes real-estate prices to rise so houses are out of reach of the middle class without taking on excessive debt and becoming house poor.  This also means that any extended dip in house prices and employment can stress banks as their loans go bad.  This is what happened during the housing crisis.
  4. It forces pension funds to speculate in stocks in order to meet their obligations.  This means that any extended dip in stocks will cause a number of these pension funds to become insolvent, putting their ability to pay out pensions at a risk.
  5. It leads to rampant financial engineering by companies where they take on long term debt to buy back their own stock enriching their stockholders and executives.
  6. It exacerbates wealth inequality in society since people that are wealthy to begin with (e.g. private equity, hedge funds, large businesses) have access to cheap money that retail investors and small businesses do not.
#3 and #4 pretty much mean that once ZIRP/NIRP are used by the central bank, the entire economy becomes dependent on frequent and larger interventions by the central banks.  At some point in time (I think we are already there now) the central banks own the entire market and there is no more real price discovery.

Proponents of ZIRP/NIRP argue that the pros outweigh the cons.

How to invest in a ZIRP/NIRP environment?

This is hard question to answer and I'm not really qualified to do it, but here are some of my thoughts.

Simple investment in savings and CDs are not likely to yield much.  I'm not a big fan of "yield chasing" where you open an account with an online bank only to have them reduce their rates a few months later.  Typical yields in a ZIRP environments are close to zero, lower than 0.1%.  That amounts to an annual return of less than $1000 on each $100,000 invested.  And then there's typically taxes that need to be paid even on those measly returns!

I don't like the idea of being forced to invest in stocks especially since there's an ethical dilemma where I don't want to support the kinds of financial activity that is destroying people's lives.  I know stocks will go up (don't fight the fed, as they say), but still.

Gold is an option, but one has to be careful of the pitfalls of investing in various types of gold and the possibility of price manipulation.

Treasury products such as I Bonds and EE Bonds are a possibility but you have to create and manage an account with treasurydirect.gov and some folks have reported less than desirable experiences when needing any kind of customer support.  The products also aren't as liquid--minimum holding period, interest penalty if cashed within a certain time period, etc., and there are annual limits on the amount that an individual can buy each calendar year -- $10K of each as of this writing.

If I figure something out, I will update this post.

In the meantime, this is what the chair of federal reserve thinks savers should do.  It just amazes me that the chair of the federal reserve and many politicians equate a 401(k) with risk assets.  It doesn't have to be that way.  Most 401(k)'s offer a stable value fund or money market fund as an investment option.  Those 401(k) savers are not benefitting from the federal reserve's policies.

Update 06/27/2020

The fed made a statement saying they will keep rates near zero until at least 2022.

Tuesday, December 3, 2019

Water hardness

I was trying to find out whether I would benefit from using a water softener with my dishwasher.

First, I contacted my local water supply and they pointed me to this report:
https://www.roseville.ca.us/UserFiles/Servers/Server_7964838/File/Government/Departments/Environmental%20Utilities/At%20your%20service/Water%20supply/Water%20quality%20reports/EU_WaterQualityReport_2018_DigitalVersion.pdf
The report has a line that says the water hardness is 24 ppm if coming from the lake or 90-250 ppm if coming from groundwater. Based on my ZIP code, I was also told that my area is serviced entirely from the lake.

However, the appliances measure water hardness in degrees of hardness.

So I found this calculator:
https://www.lenntech.com/calculators/hardness/hardness.htm
I plug in 24 ppm and get 1.35 German degrees of hardness.

Over to the dishwasher manual and I see a line:
"Water supplies with a hardness level higher than 4 gr/gal (4 °d) needs to be softened."
Going by that it looks like I would not benefit from having or using a water softener.

Thursday, January 17, 2019

2019 Acura RDX Tech SH-AWD review

Here's a brief review of the 2019 Acura RDX with the Technology Package and SH-AWD.  I was mostly drawn to the car for its seat comfort.  The Technology Package is one level above the base model.  I chose it mainly because I wanted parking sensors and leather seats.  Otherwise, the base model would have been adequate.

Features I like:
  • Seat comfort.
  • Headlight intensity -- illuminates the road very well.
  • Quality of materials.
  • Interior and exterior design.
  • NSX inspired shifter/center console.
  • Steering, handling, power.
  • Ride comfort.
  • Cap-less fuel filler.
  • Option to automatically reset trip computer on refuel.
Features that are OK but that could be improved:
  • The padding in the seat pan could be better so that it removes pressure from the low back.  Look at Volvo and Tesla, for example.
  • Gauges could be made less busy.  No need for km/hr and mph at the same time in a digital speedometer.
  • When switching between displays in the center, it would be better if they didn't shrink, then switch back to normal size after a delay.  And re-do the information to be less wordy.
  • Better ambient lighting.  Map lights feel underpowered.
  • Change to a touchscreen infotainment.  Existing setup is prone to hunting unless you look at the screen and at the touch pad, which means we're not paying attention to the road.
  • Better implementation of rear camera.  Currently unusable in rain, leave camera on for a few seconds when switching from R to D, more accurate guidelines (lines don't match up with the where the car's wheels are).  (Advance trim would help with rain since it has a camera washer.)
  • Move the BSI (blind spot indication) from the A pillars to the mirrors.
  • Road departure warning is overly sensitive, especially on internal roads.
  • Lane keep assist doesn't work very well.  It keeps asking for the driver to take control.
  • Lane departure warning is too sensitive and keeps buzzing even when within the lane.  I was forced to disable it.
  • Quality control issues.  Several rattles and issues with the audio system.
  • Interior could be quieter.  I registered 90+ dB on the highway using the Decibel X app on my iPhone.   The quietest cars register somewhere in the mid 60's.  (Advance trim would help since it has acoustic side glass.)
  • MPG. Fortunately gas prices are muted and will likely remain that way as more cars switch to hybrid/electric drivetrains.
  • No way to turn the headlights off when the car is moving in the evening.
  • The chrome pieces on the steering wheel, but especially on the center stack, can sometimes, depending on how the sun is hitting it, reflect blinding light directly into the driver's eyes.  Should be replaced with something non-reflective.
  • Rear visibility, especially the sides is very poor.
  • The parking sensors don't extend to the sides of the bumpers and only warn about objects directly in front of or behind the car.
  • Software updates are over the air, but map updates must be done via USB and the upgrade process is kludgy and prone to failure, causing a lot of frustration.  I discovered that the system doesn't like the USB drive to be larger than 64GB, and that is must not be a Sandisk!
  • OEM tires are noisy.
Tip: When you're on a call, the multi-information and navigation displays are covered by a message saying "call in progress".  To be able to view the displays, one has to hit the "back" button on the steering wheel.  Without that, it is not possible to view the trip computer or miles remaining, nor is it possible to view the map or access the navigation.

Problems I have had with the car
  • Crackling speakers: Intermittent problem that I noticed since the car was new.  Not fixed.
  • Squeaky tailgate: Happened around 5000 miles.  Fixed under warranty.
  • Whistling when engine starts or shuts: Happened around 7000 miles.  Fixed under warranty TSB.
  • Infotainment will prompt for update even though no update is available.  Fixed in D1.2.1.
  • Rubber lining near the tailgate lock has a gap.  Fixed under warranty by adjusting the lining.
  • Ticking sound when starting the engine.  Intermittent problem.  Fixed under warranty by adjusting the PCM bracket.
  • Numerous rattles all over the interior started to appear after about a year.  Not fixed.
  • When starting on a trip from home the infotainment system booted up and threw an error "Unfortunately, AcuraLauncher has stopped".  Did not happen again on the return trip.  Not fixed.
  • Received recall notice from Acura to replace the fuel pump motor.
  • Clock doesn't automatically adjust for daylight savings even though all clock settings are auto (detect time zone, set time, etc.).  Fixed by changing to manual mode for settings and, after some time, switching back to auto.  (Update: Continuing to occasionally see problems with the clock being off by an hour.)
  • Intermittently started to get a warning for "Drive mode change unavailable" at the bottom of the infotainment display.  Not yet fixed.
  • Parking sensors are being triggered in rain without any reason.  See video.  Not yet fixed.
Additional Info

Sunday, January 13, 2019

Being positive vs peaceful to manifest good health

I often hear well-meaning friends and relatives say "be positive", which doesn't resonate with me because I don't believe in faking it.  I recently came across this video where Deepak Chopra says:

@ 6:15
It's not that you have think positively all the time.  You have to get in touch with your emotions, you have to share them with somebody that you love, you have release them, you have to express them, because if you repress emotions that creates its own biology too.
@ 8:30
A peaceful mind is more important than a positive mind.  Because a positive mind can be working really hard at it, can be stressful to be positive all the time.  But when you're at peace, that's a wholly different thing because all the biochemistry of anxiety disappears.

Monday, December 10, 2018

BMW E46 -- The last of the ultimate driving machines

I first was introduced to the BMW brand on a trip to Germany in the summer of 1997 where I had the chance to drive an E36 316i part of the way from Munich to Berlin and back.  It had a puny 1.6 liter 4 cylinder rated at 101 hp.  It had cloth seats and manual rear windows and climate control.  The car felt great around town and handled superbly at high speeds on the autobahn.

By the end of that year, I was looking at replacing my then aging 1988 Nissan Sentra and looked getting a an E36 318ti which was the lowest spec BMW available in the US at the time.  I decided it would be too expensive for me, so I passed on it and I decided to get a 1998 Honda Civic EX instead.  The Civic was a fun car by itself but it was no BMW.

Five years later, at the end of 2002, after the Civic was damaged in an accident and declared a total loss, I decided to get a 2003 E46 325i.  This was the lowest spec BMW available in the US at the time.  I placed an order for the car in October 2002.  I ordered the base car with only a moonroof as an added option--I didn't care about luxury, but I knew it would feel a lot better than the Civic even in its base trim.  The car arrived in December 2002.  I drove that car for almost 11 years putting more than 211000 miles on it.  It was a simple car.  It was the most fun car I have owned.  I loved the design inside and out.  It was ergonomically and aesthetically perfect.  I knew somebody had sweated every little detail that brought this car together.

I don't track cars and I'm not motivated by speed or 0-60 times.  Nor am I a technophile so I don't care about cameras, heads up displays, autonomous driving capabilities, and other such gizmos.  In fact, I'd go so far as to say that I am a technophobe.  I prefer less technology because it means fewer things that can go wrong.   What did I like about the E46?  Let's start with the engine--it was a 2.5 liter inline 6 naturally aspirated engine that was silky smooth.  It made me smile every time I turned the ignition and heard it come to life.  While driving, the car emitted a wonderful exhaust note and the naturally aspirated engine offered linear acceleration.  The steering allowed the driver to feel the pavement as the car was being driven.  The suspension kept the car planted with a feeling like it was on rails while at the same time cushioning bumps.  Between the engine note, steering feel, and suspension tuning, this car felt special even crawling around at 10 mph in a parking lot.  On the highway it offered a planted feel no matter the speed.  It made me feel confident almost begging me to push the car harder.  Likewise when driving on winding roads--I could take curves much faster than I thought I could.  In fact, the sales guy had warned me at the time of taking delivery "Be careful.  If you don't watch the speedometer, you will get tickets.  It is very easy to speed in this car."  He was right.

And there were other aspects of the car like the full size spare in an era where almost all manufacturers were offering a compact spare.

E90 -- Polarizing styling but still drives like the ultimate driver

The E46 was succeeded by the E90.  By then BMWs had been subject to polarizing styling by Chris Bangle.  Both the exterior and the interior were impacted.  The interior lost its ergonomics with the center console no longer tilted towards the driver.  The cupholders were flimsy pop-outs.  The gauge cluster lost its coolant temperature gauge.

But all of these design flaws were forgotten once you got behind the wheel.  The sublime inline six, the steering feel, and the suspension were all intact with this generation.  The only thing that BMW meddled with from a driving dynamics standpoint was the introduction of run-flat tires.  This was premature on BMW's part.  While the goal was noble -- to have tires you could drive on even with zero tire pressure to get to safety in times of a flat -- the technology wasn't ready.  The first and even second generation of run-flats were too harsh and too noisy.  (BMW's best driving cars, like the M3, continued to offer regular, go flat tires.)  This made the uninformed customer incorrectly think that BMW's suspension was too harsh.  Word in BMW forums was "swap out the run flats, and you have a car that drives like a BMW should."

Also in terms of specs, when the E90 was introduced, it was a better car in every way than the E46 that it replaced, with the exception of size and weight.  For example, BMW went from offering a 10-speaker audio system that was standard in the E46 to a 12-speaker system that was standard in the E90.

E90 de-contenting

Starting around 2009, BMW started de-contenting their E90s.  A number of features were silently removed.  Many enthusiasts who thought they were getting a similar car to their older E90 were disappointed to find many missing features.  In some cases were able to get BMW to buy the car back because it fell so far short of their expectation.  A few examples of the de-contenting -- The stereo system went from 12 speakers to 6.  The flashlight in the glove box was gone.  The storage nets behind the front seats was removed.  The pad under the hood was removed.  While BMW had, in the past, provided extremely detailed specs for every aspect of the car, they no longer provided that information.  In fact, it even became hard to get an answer for "how many speakers does the car have" even from the dealer!

This is perhaps the biggest reason I decided to forego the E90 and just kept maintaining my E46 even though it was very expensive to do so as the miles kept climbing beyond 150,000.

F30 -- The ultimate marketing machine

The F30 had a rushed introduction.  Instead of the normal 7 year cycle, the E90 had a shorter, 6 year run, with the F30 being introduced a year early as a MY2012 car in early 2012.  The car was the polar opposite of the E90.  The design was gorgeous inside and out but it had none of the driving attributes of a BMW.  The engine was a turbo 4 with an uninspiring exhaust note.  The engine was responsive, but being a turbo it lost its linear power delivery and offered more of a slingshot feel.  The steering was an electric power steering that was more numb than even a pedestrian Honda.  The suspension was either too floaty (giving the driver a feeling of bouncing at highway speeds) or too hard (sending shocks up the spine at even the mildest of imperfections) and had completely lost its planted, "riding on rails" feeling.  The run-flats carried over from the E90, but they were improved 2nd generation run-flats and rode a little less harsh.  In terms of driving dynamics, the only thing that remained from BMW DNA was the rear wheel drive and near 50:50 balance.  The car could be packed to the gills with technology and BMW would charge an arm and a leg for it.  Their implementation of technology is good, but nothing special compared to that offered by other luxury marques.

BMW had a whole bunch of ads touting it to be the ultimate driving machine.  I think of it as the ultimate marketing machine.  I fell for it.  I owned 2 of them.  First a no line which cause me severe buyers remorse but which BMW bought back because of recurring problems.  Then an M-sport which I hoped would provide an improved driving experience, which it did compared to the no line car, but was still no match for the E46 and E90 in terms of steering and suspension.

I finally realized BMW had changed from building a car that excites to building a car purely for profit while capitalizing on their brand.   I am no longer a BMW owner and probably never will be.  I find their recent styling borders on gaudy, flashy, and gimmicky.  There are many better choices for the enthusiast now, e.g. the Alfa Romeo Giulia or the Jaguar XE.  In a recent comparo by Motortrend magazine, the F30 placed 7th out of 8 cars tested.  This from a car that simply could not be beat year after year no matter how hard the competition tried.

Their most recent car designs border on gaudy.