Fix blue tint on MacBook Pro dedicated GPU

This post is primarily a reminder for myself on how to purge/reset the ColorSync user cache.

I’ve got a mid-2010 15″ MacBook Pro, which was the first having both an integrated GPU (Intel HD) and a dedicated GPU (NVidia Geforce GT 330M). It “dynamically” switches between the two on-demand, which means some applications (e.g. Adobe Photoshop, Google Chrome, Visual Studio Code) trigger the switch, probably because of some low-level GPU call that makes OS X decide the dedicated GPU must be used.

Now, since a while, when the MBP would switch from the internal GPU (iGPU) to the dedicated GPU (dGPU), the screen would change colour. It would change from its correct colour to a somewhat blue-ish tint. Very bad on the eyes, especially in the evening.

After googling around a lot, a number of posts on the Apple Discussions pages recommend gfxCardStatus, using which you can “lock” the MBP on the iGPU. I consider this a bad option (it’s not bad software by the way, I’ve used it in the past to monitor the GPU switching), since the dGPU is far more powerful than the iGPU and often you need that power (be it the dedicated memory or the computation power). And, when you attach an external screen (like I do most of the times), it doesn’t work at all.

I also found the recommendation to reset or purge the ColorSync user cache. I tried this and it immediately worked, removing the blue-ish tint from the MBP screen (well, after removing the ColorSync cache and restarting the MBP).

The easiest way to do this (in my opinion), is described by Topher Kessler on in his post titled “How to make ColorSync profiles stick in OS X”. It took me a while to find it because the title doesn’t immediately give away the fact that it concerns the ColorSync cache.

So, long story short, execute the following in the Terminal:

sudo rm $(getconf DARWIN_USER_CACHE_DIR)`id -u`

…which gets rid of the existing ColorSync user cache. Restart afterwards and the screen will maintain the same colour on both the iGPU and the dGPU.

I don’t know why or how the ColorSync user cache gets corrupted, but I do know how to solve it!

Remove hyphenation from WordPress Twenty Fifteen theme

After using the same WordPress theme since 2007, the time had come to switch. I quite like the default Twenty Fifteen theme, so I switched to that. I immediately noticed words in the site started automatically hyphenating. I don’t like that.

Continue reading Remove hyphenation from WordPress Twenty Fifteen theme

Verify the integrity of a flash/SD card on a Mac

Last minute camera shopping

The week before going on a holiday, I realised my old Canon Ixus 40 camera would no longer live up to my expectations. So I quickly checked for the latest and greatest compact camera’s and decided I wanted the Canon PowerShot SX240 HS. 15 Minutes later I found myself in the Media Markt with the camera in my hand (unfortunately only the silver colour was available, I had hoped to buy the black one).

I need a bigger memory card

I then realised that my existing 512MB and 1GB SD cards would no longer be large enough for the 12Mpixel photos of this new camera. A few meters down the corridor was a huge wall covered in memory cards. I decided to buy a Samsung 8GB SDHC card, which would be able to hold up to 1500 photos or an hour of HD video. When I returned home, I formatted the card in-camera, and played around with the photo and video functions. Three days later my holiday would start and I would have a good (enough) camera to capture some fine moments!

Corrupted photos

Fast-forward about two weeks, half-way into my holiday. I’ve happily been taking photos and videos with my new camera. While I’m reviewing the last five photos, the camera suddenly displays a “broken picture” image on the screen. I take another photo, review it and it’s immediately “broken” again. I’m approximately on two-thirds of the card’s capacity and it is corrupting my photos. I do what I’ve learned from experience with corrupt memory cards: turn off the camera immediately, remove the SD card, and to be sure, “lock” the card (making it read-only) using the physical switch on the SD card. At this point, I just hope for the best that only those last two photos were corrupted.

Back at home a week-and-a-half later, it turns out I’m extremely lucky! Indeed only those last two pictures were corrupted! Continue reading Verify the integrity of a flash/SD card on a Mac

De mooiste (portret)fotografie

Kortgeleden was ik bij een nichtje van mij –Janneke Walter– om éindelijk eens de foto’s te aanschouwen die ze tijdens een reis door Bolivia had geschoten. Ik wist dat ze ondertussen redelijk had geïnvesteerd in camera en lenzen en kon zien dat dat geld goed was besteed.
De foto’s die het meest in het oog sprongen waren de portretten, krachtig, scherp, met de gezichten prachtig uitgelicht tegen de achtergrond. Ik denk dat voor elk van ons geldt dat een krachtige portretfoto veel emoties kan losmaken en haar portretfoto’s doen dat absoluut.
Ik was dan ook blij verrast toen ze me vertelde dat ze zelf ook overtuigd was geraakt van haar eigen kunnen, dat ze haar technische vaardigheden eindeloos had bijgeschaafd (ze is na de reis waarschijnlijk net zo lang bezig geweest met het verkrijgen van het ‘juiste’ beeld per foto, heel perfectionistisch, als met de reis zelf), maar vooral: dat ze haar kennis en kunde graag als dienst wil aanbieden.
Janneke werkt als optometrist en weet dus vanuit haar professie al ‘alles’ over de fysische en biologische kant van licht, de ogen en de beeldverwerking door de hersenen. Haar professionele interesse in “beeldverwerking” gaat dus gepaard met een passie voor fotografie.
Ondertussen heeft ze een aantal portretfoto’s gemaakt, zoals ook op haar website te zien is. Zelf zegt ze hierover:

“Op de één of andere manier krijg ik het altijd voor elkaar om precies dát moment te vangen, waarop iemand stráált. Soms na een paar minuten, soms na een uur, maar altijd is er een moment tussen mij en mijn onderwerp dat er uitspringt en dat ik weet te vangen!”

Volgens mij is dat precies haar kracht! Dus wilt u een prachtige, krachtige portretfoto van uzelf, met aandacht voor ú als mens, denk dan ook eens aan Janneke Walter (portret)fotografie!

Restore an Apple Partition Map

Update Nov 19, 2009
— I just came accross an open source piece of software that might do all of the manual work described below for you. It’s called TestDisk, open source data recovery software.
I haven’t used it, but it looks very promising! —

Original article, Jan 4, 2008
Say you’ve got an external harddisk in a Firewire or USB enclosure. It’s Apple Partition Map (APM) partitioned and contains a couple of HFS+ Journaled formatted volumes. You’re happily using it on your Mac and for some reason you’ve decided to hook it up to a Windows PC. You’ve installed MacDrive on it, but somehow it doesn’t recognize the volumes that are on it. You check the Disk Management tool and you notice a red stop sign on the external drive. When you right-click the symbol, you’re able to “initialize” the drive. You hesitate for a second, but decide it must mean something like “just start the damn thing up, so that it works” (later on you know that this must have been your weakest moment of that day, maybe even the entire week, but at this “moment suprême” you feel it’s the only choice). And then, disaster strikes. Cause “initialize” means something entirely else. The Disk Management tool has just overwritten the APM with a Master Boot Record (MBR) and all partition information seems lost.
That is exactly what happened to me last week. After extensive searches on the internet, the only option seemed to be to buy and use a data restore/recovery program like Disk Warrior II, which meant copying/restoring/recovering the full 250GB of info to another harddisk, which I don’t have. It seemed wrong, the only thing gone was the partition information, the data was still there, why should I spend money on: a) software; b) hardware; to recover “undamaged” data?
Then I found this post on and it made me see the light.
Before you start doing anything I recommend reading through all below-mentioned steps and then decide whether you can do this. Furthermore note that the disk I used was originally partitioned using an Apple Partition Map. Recent (Intel) Macs have been formatted using GUID Partition Table (GPT) and I have no clue at all whether this will work on GPT drives.
Continue reading Restore an Apple Partition Map

Just starting up

Hey and welcome! As you can see this site is just starting up… Guess I’ll need to put a big “Under Construction” sign here, which is of course “so 90’s”. So I won’t.
If you came here for the photo’s of the Milano furniture fair that were hosted here, too bad. They’re no longer here and they won’t be again. then here they are!

When you’re looking for the NL Weerradar widget for MacOSX, just follow this link, it’ll bring you right to it!