Mark's Blog about Tech and Cool Stuff

I have succeeded in getting a Brother HL-2135W laser printer working across VLANs.  I assume this solution will work for most if not all Brother network printers.  Subsequently, I've found that the same protocols are used by an Epson WF-3640 inkjet printer and the solution also works for that printer. I quickly worked around Windows printer discovery by entering the static IP address in to the printer Port configuration. But I had struggled to get the Brother Print Services (Android) plugin working.  The solution required some firewall rules and a utility to send broadcasts between VLANs.

Easy MKV to MP4 Recently I discovered that Davinci Resolve  (NLE and Color Grading software) is incapable of reading MKV ("Matroska" multimedia container) files.  MKV files are my go-to container format simply because of the convenience, given that there are utilities provided for muxing/demuxing and it supports any video or audio formats you want to use within the container. Unfortunately the Davinci Resolve media pool just ignores files with that extension.  Shame on them, I would have expected them to adopt open standards like Matroska.  For what it's worth it looks like other NLE software like Adobe Premiere Pro does not support it either.  I guess their justification is that they only need to support the formats that cameras record in. Anyway, given I was working with H.264 video and AAC audio, I knew I should be able to put multiplex into a MP4 (or even MOV) container to make it compatible with Davinci Resolve. A quick Internet search found crazy posts an...

I've upgraded my home network to use separate VLANs for security, specifically keeping IoT devices and guests off my main network. One device that did not "just work" is the air conditioning controller tablet from Advantage Air .  While the controller device was functional, I could not get the mobile app MyPlace to connect from the source (secure) VLAN to the IoT VLAN. To figure this out I had to do some Wireshark analysis.  Not only did I figure out how to get MyPlace to work across VLANs, but I also discovered how to improve the app connection reliability.

Blogger has enabled secure browsing of blogs which are hosted at a custom domain - i.e. not at blogspot.com. As Google themselves say here : It helps check that your visitors open the correct website and aren’t being redirected to a malicious site. It helps detect if an attacker tries to change any data sent from Blogger to the visitor. It adds security measures that make it harder for other people to listen to your visitors’ conversations, track their activities, or steal their information. Importantly, Google is taking steps to give priority to HTTPS websites in search results . Furthermore, by July 2018, the Chrome browser will highlight HTTP websites as "Not Secure" . The change is quick and easy, and will not result in any downtime for your blog.  Existing links will continue to work, and can be automatically redirected to the secure pages.

GitLab has built-in backup and restore capability, but it is not immediately apparent how to use backup and restore on the Synology NAS installation of GitLab.  The following instructions may also be applicable for other Docker based GitLab installations. This post will explain how to protect your data in the GitLab repository.  This is protecting against a catastrophic RAID failure, and also accidentally corrupting/destroying the repository.  Please ensure you have backups stored off-site, and ideally multiple versions of the backup data. With any backup/restore procedures it is important that you are able to test/validate the ability to recover your data before you need to do so. TIP: Check out my quick fix if you get the dreaded GitLab 502 error .

Fitbit does not natively integrate with Google Fit on Android.  However Prevaeen Kumar Pendyala has developed an excellent open source Python based utility to perform the data synchronisation. You can read more about his utility here: https://pkp.io/blog/fitbit-to-googlefit-sync/ And download the code, and access his installation instructions here: https://github.com/praveendath92/fitbit-googlefit The code will work on any computer, and detailed instructions/video are provided for installing on Windows, MAC or Linux.  The purpose of these instructions is assist with deploying on a Synology NAS.  The benefit of using your NAS is you don't have to remember to turn on your computer.

I use a calibrated monitor for editing photos, and recently I've had photos where the colours were clearly wrong and couldn't be fixed without complex adjustment layers. The problem was most evident in portraits.  For example, this image taken in sunlight: Original image captured in sunlight Instead looked like this, where her hair has turned an orange/magenta colour, and she also has what appears as a feint orange rash on her forehead.  Note this is a photograph of the monitor, and I've tried to adjust white balance, contrast and saturation to reflect accurately the colours I was seeing. Photograph of screen showing incorrect colours What had gone wrong? Image fault on my Dell U2311H monitor Sensor problem on my Canon 7D Mark II DSLR (9 year old) ColorMunki Photo spectrophotometer could have developed a fault Photographic software playing up.