Mark's Blog about Tech and Cool Stuff

Temporal Denoising Toolkit I have created a Node Group for Blender which allows you to perform "Temporal Denoising".  The Node Group is available for free from  Gumroad  and you're welcome to tweak or customise it as you wish. Temporal Denoising is where multiple frames are intelligently combined to reduce image noise.  It should be combined with the traditional Spatial Denoising provided by OpenImageDenoise . Temporal Denoising is designed for use in animations.  It's main strength is reducing flickering between frames.  Even when you crank up the number of samples for Spatial Denoising there can still be flicking since the denoiser has no way of knowing if there consistency between frames. I have a detailed video that explains how the Temporal Denoising works under the hood, and the configuration/operation. However this video doesn't provide examples showing how to combine Temporal and Spatial Denoising. Spat...

Overview It was not obvious how to easily upgrade Synology Docker containers.  The process I used to use involved manually copying settings into a new container.  However, there's a better way. The process outlined below is the easiest technique to upgrade using the GUI.  I've found it to be a reliable process, and I now use this for all upgrades. It should be possible to also perform this kind of upgrade using the command line and then execute manually as using the Task Scheduler.  I'll probably look into that down the track. Assumptions This process assumes that your configuration and data is stored outside of the docker container. Please ensure you have a backup process too. The process I'm documenting is for DSM 6.2, and I assume it is similar for later versions. This upgrade only works when the tag/version is unchanged - so would only work for a tag like latest or stable, but not a specific version like 1.2.3. Ideally confirm the version of the containerised sof...

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.

I made a YouTube video of my daughter back in 2010, and it briefly went viral.  To date it has reached 113499 views, 438 likes (6 dislikes) and 86 comments still listed. Today I received a copyright claim by "AdRev for Rights Holder".  It states that they have a copyright claim for the music "Medieval.-16004-RFR - Manuel Kempter".

Julian calendar The Julian calendar was introduced in 45BC by Julius Caesar, taking over from the  Roman calendar . Under the Julian calendar each year has 365 days, except for a leap year  every four years which has 366 days.  This averages to 365.25 days.  This however does not approximate the actual tropical year  (e.g. based on the cycle of the seasons) close enough.  Specifically the average year was slightly longer than it should have been (365.24219). So how bad is the Julian calendar? 365.25 - 365.24219 = 0.00781 days 0.00781 * 24 * 60 = 11.2464 minutes It was gaining about 11.2464 minutes per year.  Hardly consequential - right?  Well, that results in an increase of 1 day every 128 years or so.  By now (2017) it would be 13 days out.  Though after 46,766 years (or so) the Julian calendar would be correct again... Gregorian calendar The problem was (mostly) corrected with a new calendar introduced by Pop...

I have a lot of travel photos taken on my DSLR that are missing the GPS location.  Having the location is handy for friends and family to see exactly where the photos were taken from.  Over time your own memory fades too. Most of my photos are in raw format (Canon CR2), and I can use Picasa to set the GPS location, but only after the photos have been processed and saved as JPG (or TIFF etc).  If I add the location to the raw image, then it saves the location to metadata that only Picasa recognises. If I go back and reprocess the raw photo, then the new JPG will have lost the location information.  What I needed was software that could add the location to the raw photo. I looked around for alternate software, and did try a few things.  Usually they didn't work on raw files, or were just clunky to use.  Many applications are also designed for taking coordinates from GPS loggers - which I don't have. Furthermore, I don't want to have to type in GPS c...

Picasa  is a quick and handy picture viewer and organiser for all the photos on your PC. Picasa was discontinued by Google in 2016 when they chose to focus exclusively on the cloud. Even though it was discontinued, Picasa is still my preferred software for viewing, searching and managing photos. This post will explain how you can still use Picasa, and specifically integrate with the new Google Photos cloud storage. In short Picasa is still useful.  Furthermore by integrating with Google Photos, you get great cloud hosting for backup and sharing.

How to fix the GitLab 502 error Occasionally when starting GitLab, I get a 502 error ("Whoops, GitLab is taking too much time to respond").  It appears to happen when my Synology NAS has restarted after a power outage. Checking the Docker GitLab log, I can seen continual messages about trying to restart the "unicorn" process.  This also causes high CPU usage. 2017-03-27 00:35:08,892 INFO spawned: 'unicorn' with pid 27723 2017-03-27 00:35:09,896 INFO success: unicorn entered RUNNING state, process has stayed up for > than 1 seconds (startsecs) 2017-03-27 00:35:14,277 INFO exited: unicorn (exit status 1; not expected) ...

In February 2010, I purchased an 82mm Fader ND Filter (ND2 to ND400) from the official eBay store for Light Craft Workshop .  The label on the filter reads "82mm  Fader ND [W]  HL-OPTICS". The purpose of a Neutral Density (ND) filter is to reduce the amount of light, therefore allowing for slower shutter speeds.  A variable ND filter allows you to vary the amount of light by rotating the front of the filter. When shooting video, the shutter speed is normally fixed - it is tied to the frame rate giving the required Shutter Angle (e.g. 180 degrees) controlling motion blur.  When shooting video, the only way to prevent over exposure in bright light is to Stop Down the aperture.  This limits your ability to use the aperture to control depth of field. A variable ND filter is particularly useful for video, since it allows you to control exposure independently of the aperture and ISO.  Specifically you set your fixed shutter speed, choose your depth...

We've now got five chickens, having purchased another two today. This is our family of hens. "Beatrice" is a Silver Laced Wyandotte , purchased 13th June 2010. "Snowball" is a White Wyandotte Bantam , purchased 13th June 2010. "Dotty" is a Cuckoo Pekin Bantam , purchased 1st November 2009. Sadly she had to be put-down on 7th March 2011 after developing paralysis from a virus. "Edna" is an Isa Brown , purchased 1st November 2009. "Dora" is an Australorp , purchased 1st November 2009. Click here to view more photos of our hens.

Recently I wrote about how I had designed an automatic door opener for our chicken coop by modifying an alarm clock.  Refer to this post ( Building an automatic chicken door opener ) for more details of the design. The automatic door opener has been installed into the new chicken coop, here's a video of it in action. Our three hens come out in the order Dora first, then Dotty the bantam and then finally Edna pushes past. The new chicken coop is much larger than the old one. Note the chicken coop is a one-off, home-made design purchased off eBay, which we've then modified to suit our needs. There's plenty of space in the nesting boxes for our hens .  In fact it's probably too big now, so we'll definitely have to get some more girls. Plus the most important thing, I've converted my automatic door opener to suit.  Now it operates vertically, and hence why the clock is on a 90 degree angle. The operating mechanism is much less prone to error.  Specifica...

I bought a FOSCAM FI8908W wireless IP webcam off eBay recently. It has lots of features for the price. However, I've had problems with being unable to connect to the camera after a period of time (an hour or so). Power cycling the camera would fix the problem. I've tried upgrading to the latest firmware (version 11.14.2.17 is supposed to fix WiFi disconnection problems), but it did not fix my problem. Problem analysis The problem is not related to my browser or the wireless network. I've tried disabling DHCP (router based static IP). It turns out the problem is that the webcam simply ceases to respond to ARP  (Address Resolution Protocol) requests (once in this broken state). ARP is a mechanism to translate between IP addresses and device MAC addresses. It underpins all IP communications over both Ethernet and WiFi, since at the lowest level it relies on exchange of packets between device MAC addresses. The ARP protocol allows a network device to discover t...

A photographic light tent or cube is invaluable for product photography.  It allows you to light a photographic subject with soft shadows and a non-distracting background such that a photograph will look its best.  It is ideal for product photography such as when you're selling things on eBay.  These eggs were photographed using the light tent: The tent is sold in a folded/collapsed shape, but when you open the package it springs open.  It is very difficult to collapse back into the original shape - if you don't know the technique. I purchased my light tent from DealExtreme here:     http://www.dealextreme.com/details.dx/sku.5224 Many of the customer comments say that they can't figure out how to collapse the light tent for storage or transportation.  Taking note of this, I was very careful when I first opened the light tent.

Any modern DSLR camera supports (or should support) predictive autofocus tracking. While they might have this capability, there is an art to using it effectively, and therefore getting in-focus shots of moving subjects. This is actually something I only learnt on the 19th of August, 2009.  Yes, I remember the date, it's an important date.  This is after having a DSLR many years, and never being able to effectively shoot moving subjects.  I would resort to doing things like: Stopping down , therefore increasing the depth of field, such that the moving subject might still be in focus. Increasing the shutter speed ('cause clearly I didn't understand the difference between motion blur and just plain out-of-focus). Pre-focusing in front of a moving subject. These can give acceptable results, but why not get the camera do what it's supposed to do.