Total of 297 posts

Herein you’ll find articles on a very wide variety of topics about technology in the consumer space (mostly) and items of personal interest to me.

If you’d like to read my professional engineering articles and whitepapers, they can be found at Control System Space

I have also participated in and created several podcsts most notably Pragmatic and Causality and all of my podcasts can be found at The Engineered Network.


I’ve been on the receiving end of failing hard drives in the past and lost many of my original podcast source audio files and more importantly a years' worth of home videos, gone forever.

Not wishing for a repeat of this I purchased an 8TB external USB HardDrive and installed BackBlaze. The problem for me though was that BackBlaze was an ongoing expense, could only be used for a single machine and couldn’t really do anything other than be an offsite backup. I’d been considering a Network Attached Storage for years now and the thinking was, if I had a NAS then I could have backup redundancy1 plus a bunch of other really useful features and functionality.

The trigger was actually a series of crashes and disconnects of the 8TB USB HDD, and with the OS’s limited ability to troubleshoot HDD hardware-specific issues via USB I had some experience from my previous set of HDD failures many years ago, that this is how it all starts. So I gathered together a bunch of smaller HDDs and copied across all the data to them, while I still could, and resolved to get a better solution: hence the NAS.

Looking at both QNAP and Synology and my desire to have as broad a compatibility as possible, I settled on an Intel-based Synology, which in Synology-speak, means a “Plus” model. Specifically the DS918+ presented the best value for money with 4 Bays and the ability to extend with a 5 Bay external enclosure if I really felt the need in future. I waited until the DS920+ was released and noted that the benchmarks on the 920 weren’t particularly impressive and hence I stuck with the DS918+ and got a great deal as it had just become a clearance product to make way for the new model.

My series of external drives I had been using to hold an interim copy of my data were: a 4TB 3.5", a 4TB 2.5" (at that time I thought it was a drive in an enclosure you could extract), and a 2TB 3.5" drive as well as, of course, my 8TB drive which I wasn’t sure was toast yet. The goal was to reuse as many of my existing drives as possible and not spend even more money on more, new HDDs. I’d also given a disused but otherwise healthy 3.5" 4TB drive to my son for his PC earlier in the year and he hadn’t actually used it, so I reclaimed it temporarily for this exercise.

Here’s how it went down:

STEP 1: Insert 8TB Drive and in Storage Manager, Drive Info, run an Extended SMART test…and hours later…hundreds of bad sectors. To be honest, that wasn’t too surprising since the 8TB drive was periodically disconnecting and reconnecting and rebuilding its file tables - but now I had the proof. The Synology refused to let me create a Storage Pool or a Volume or anything so I resigned myself to buying 1 new drive: I saw that SeaGate Barracudas were on sale so I grabbed one from UMart and tried it.

STEP 2: Insert new 4TB Barracuda and in Storage Manager, Drive Info, run an Extended SMART test…and hours later…it worked perfectly! (As you’d expect) Though the test took a VERY long time, I was happy so I created a Storage Pool, Synology Hybrid RAID. Created a Volume, BTRFS because it came highly recommended, and then began copying over the first 4TB’s worth of data to the new Volume. So far, so good.

STEP 3: Insert my son’s 4TB drive and extend the SHR Storage Pool to include it. The Synology allowed me to do this and I did so for some reason without running a SMART Extended test on it first, and it let me so that should be fine right? Turns out, this was a terrible idea.

STEP 4: Once all data was copied off the 4TB data drive and to the Synology Volume, wipe that drive, extract the 3.5" HDD and insert the reclaimed 4TB 3.5" into the Synology and in Storage Manager, Drive Info, run an Extended SMART test…and hours later…hundreds of bad sectors. Um, okay. That’s annoying. So I might be up for yet another HDD since I have 9TB to store.

OH DEAR MOMENT: As I was re-running the drive check the Synology began reporting that the Volume was Bad, and the Storage Pool was unhealthy. I looked into the HDD manager and saw that my sons reclaimed 3.5" drive was also full of bad sectors, as the Synology had run a periodic test while data was still copying. I also attempted to extract the 2.5" drive from the external enclosure only to discover that it was a fully integrated controller/drive/enclosure and couldn’t be extracted without breaking it. (So much for that) Whilst I still had a copy of my 4TB of data in BackBlaze at this point I wasn’t worried about losing data but the penny dropped: Stop trying to save money and just buy the right drives. So I went to Computer Alliance and bought three shiny new 4TB SeaGate IronWolf drives.

STEP 5: Insert all three new 4TB IronWolfs and in Storage Manager, Drive Info, run an Extended SMART test…and hours later…the first drive perfect! The second and third drives however…had bad sectors. Bad sectors. On new drives? And not only that NAS-specific, high reliability drives? John = not impressed. I extended the Storage Pool (Barracuda + 1 IronWolf) and after running a Data Scrub it still threw up errors despite the fact both drives appeared to be fine and were brand new.

IronWolf Fail This is not what you want to see on a brand new drive…


So I did what all good geeks do and got out of the DSM GUI and hit SSH and the Terminal. I ran “btrfs check –repair” and recover, super-recover and chunk-recover and ultimately the chunk tree recovery failed. I read that I had to stop everything running and accessing the Pool so I painstakingly killed every process and re-ran the recovery but ultimately it still failed after a 24 hour long attempt. There was nothing for it - it was time to start copying the data that was on there (what I could read) back on to a 4TB external drive and blow it all away and start over.

Chunk Fail

STEP 6: In the midst of a delusion that I could still recover the data without having to recopy the lot of it off the NAS (a two day exercise), I submitted a return request for first failed IronWolf, while I re-ran the SMART on the other potentially broken drive. The return policy stated that they needed to test the HDD and that could take a day or two and Computer Alliance is a two hour round trip from my house. Fortunately I met a wonderfully helpful and accomodating support person at CA on that day and he simply handed me a replacement, taking the Synology screenshot of the bad sector count and serial number confirming I wasn’t pulling a switch on him and handed me a replacement IronWolf on the spot! (Such a great guy - give him a raise) I returned home, this time treating the HDD like a delicate egg the whole trip, inserted it and in Storage Manager, Drive Info, run an Extended SMART test…and hours later…perfect!

STEP 7: By this time I’d given up all hope of recovering the data and with three shiny new drives in the NAS, my 4TB of original data restored to my external drive (I had to pluck 5 files that failed to copy back from my BackBlaze backup) I wiped all the NAS drives…and started over. Not taking ANY chances I re-ran the SMART tests on all three and when they were clean (again) recreated the Pool, new Volume, and started copying my precious data back on to the NAS all over again.

STEP 8: I went back to Computer Alliance to return the second drive and this time I met a different support person, someone who was far more “by the book” and accepted the drive and asked me to come back another day once they’d tested it. I’d returned home and hours later they called and said “yeah it’s got bad sectors…” (you don’t say?) and unfortunately due to personal commitments I couldn’t return until the following day. I grabbed the replacement drive, drove on eggshells, added it to the last free bay and in Storage Manager, Drive Info, run an Extended SMART test…and hours later…perfect! (FINALLY)

STEP 9: I copied all of the data across from all of my external drives on to the Synology. The Volume was an SHR with 10.9TB of usable space spread across x4 4TB drives, (x3 IronWolf, and x1 Barracuda). The Data Scrub passed, the SMART Tests passed, and the IronWolf-specific Health Management tests all passed with flying colours (all green, oh yes!) It was time to repurpose the 4TB 2.5" external drive as my offline backup for the fireproof safe. I reformatted it to ExFAT and set up HyperBackup for my critical files (Home Videos, Videos of the Family, my entire photo library), backed them up and put that in the safe.


Looking back the mistake was that I never should have extended the storage pool before the Synology had run a SMART test and flagged the bad sectors. In so doing it wrote data to those bad sectors and there were just too many for BTRFS to recover in the end. In addition I never should have tried to do this on the cheap. I should have just bought new drives from the get-go. Not only that, I should have just bought NAS-specific drives from the get-go as well. Despite the bad sectors and bad luck of getting two out of three bad IronWolf drives, in the end they have performed very well and completed their SMARTs faster with online forums suggesting a desktop-class HDD (the Barracuda) is a bad choice for a NAS. I now have my own test example to see if the Barracuda is actually suitable as a long-term NAS drive, since I ended up with both types in the same NAS, same age, same everything else, so I’ll report back in a few years to see which starts failing first.

Ultimately I also stopped using BackBlaze. It was slowing down my MacBook Pro, I found video compression on data recovery that was frustrating, and even with my 512GB SSD on the MBP with everything on it, I would often get errors about a lack of space for backups to BackBlaze. Whilst financially the total lifecycle cost of the NAS and the drives is far more than BackBlaze (or an equivalent backup service) would cost me, the NAS can also do so many more things, than just to backup my data via TimeMachine.

But that’s another story for another article. In the end the NAS plus drives cost me $1.5k AUD, 6 trips to two different computer stores and 6 weeks from start to finish, but it’s been running now since August 2020 and hasn’t skipped a beat. Oh…my…NAS.

  1. Redundancy against the failure of an individual HDD ↩︎

200-500mm Zoom Lens Test

I’ve been exploring my new 200-500mm Nikon f/5.6 Zoom Lens on my D500 and pushing the limits of what it can do. I’ve used it for several weeks taking photos of Soccer and Cricket and I thought I should run a few of my own lens sharpness tests to see how it’s performing in a controlled environment.

As in my previous Lens Shootout I tested sharpness indoors, with controlled lighting conditions setting the D500 on a tripod, set with a Timer and adjusting the shutter speed leaving a constant shutter speed of 1/200th of a second, with Auto ISO and tweaked the Exposure during post to try and equalise the light level between exposures.

Setting the back of some packaging with a mixture of text and symbols as the target with the tripod at the same physical distance for each test photo.

Nikon 200-500mm Zoom Lens

I took photos across the aperture range at f/5.6, f/8 and f/11, cropped to 1,000 x 1,000 pixels in both the dead-center of the frame and the bottom-right edge of the frame.


200mm Edge f/5.6 200mm Center Crop f/5.6

200mm Edge f/8 200mm Center Crop f/8

200mm Edge f/11 200mm Center Crop f/11

200mm Edge f/5.6 200mm Edge Crop f/5.6

200mm Edge f/8 200mm Edge Crop f/8

200mm Edge f/11 200mm Edge Crop f/11


300mm Edge f/5.6 300mm Center Crop f/5.6

300mm Edge f/8 300mm Center Crop f/8

300mm Edge f/11 300mm Center Crop f/11

300mm Edge f/5.6 300mm Edge Crop f/5.6

300mm Edge f/8 300mm Edge Crop f/8

300mm Edge f/11 300mm Edge Crop f/11


400mm Edge f/5.6 400mm Center Crop f/5.6

400mm Edge f/8 400mm Center Crop f/8

400mm Edge f/11 400mm Center Crop f/11

400mm Edge f/5.6 400mm Edge Crop f/5.6

400mm Edge f/8 400mm Edge Crop f/8

400mm Edge f/11 400mm Edge Crop f/11


500mm Edge f/5.6 500mm Center Crop f/5.6

500mm Edge f/8 500mm Center Crop f/8

500mm Edge f/11 500mm Center Crop f/11

500mm Edge f/5.6 500mm Edge Crop f/5.6

500mm Edge f/8 500mm Edge Crop f/8

500mm Edge f/11 500mm Edge Crop f/11

What I wanted to test the most was the differences between Edge and Centre sharpness as well as the the effect of different Apertures. For me I think the sensor is starting to battle ISO grain at f/11 and this is impacting the apparent sharpness. In the field I’ve tried stopping down the Aperture to try and get a wider focus across the zoom area but it’s tough the further out you zoom and the images above support this observation.

My conclusions in terms of the questions I was seeking answers to though, is firstly there’s no noticable change in sharpness from the center to the edge at the closest zoom, irrespective of aperture. The edge starts to softens only slightly as you zoom in towards 500mm, and is independent of aperture.

The thing I didn’t expect was the sharpness at f/5.6 being so consistent, throughout the zoom range. If you’re isolating a subject at the extremes of zoom then it’s probably not worth stopping down the aperture and in future when I’m shooting I’ll just keep that aperture as wide open as I can unless I’m at the 200mm end of the zoom spectrum.

It’s a truly amazing lens for the money and whilst I realise there are many other factors to consider, I at least answered my own questions.

Astronomy With Zoom Lenses

About a month ago I started renting a used Nikon 200-500mm Zoom Lens that was in excellent condition. Initially my intention was to use it for photographing the kids playing outdoor sports, namely Soccer, Netball and Cricket. Having said that the thought occurred to me that it would be excellent for some Wildlife photography, here, here and here, and also…Astrophotography.

Nikon 200-500mm Zoom Lens

I was curious just how much I could see with my D500 (1.5x as it’s a DX Crop-sensor) using the lens at 500mm maximum (750mm effective). The first step was to mount my kit on my trusty 20 year old, ultra-cheap, aluminium tripod. Guess what happened?

The bracket that holds the camera to the tripod base snapped under the weight of the lens and DSLR and surprising even myself, in the pitch dark, I miraculously caught them before they hit the tiles, by mere inches. Lucky me, in one sense, not so lucky in another - my tripod was now broken.

Not to be defeated, I applied my many years of engineering experience to strap it together with electrical tape…because…why not?

D500 and 200-500 Zoom on Tripod

Using this combination I attempted several shots of the heavens and discovered a few interesting things. My PixelPro wireless shutter release did not engage the Image Stabilisation in the zoom lens. I suppose they figured that if you’re using the remote, you’ve probably got a tripod anyhow so who needs IS? Well John does, because his Tripod was a piece of broken junk that was swaying in the breeze - no matter how gentle that breeze was…

Hence I ended up ditching the Tripod and opted instead for handheld, using the IS in the Zoom Lens. The results were (to me at least) pretty amazing!

Earth’s Moon

The Moon I photographed through all of its phases culminating in the above Full Moon image. By far the easier thing to take a photo of and in 1.3x crop mode on the D500 it practically filled the frame. Excellent detail and an amazing photograph.

Of course, I didn’t stop there. It was time to turn my attention to the planets and luckily for me several planets are at or near opposition at the moment. (Opposition is one of those astronomy terms I learned recently, where the planet appears at its largest and brightest, and is above the horizon for most of the night)

Planet Jupiter

Jupiter and its moons, the cloud band stripes are just visible in this photo. Stacked two images, one exposure of the Moons and one of Jupiter itself. No colour correction applied.

Planet Saturn

Saturn’s rings are just visible in this image.

Planet Mars

Mars is reddish and not as interesting unfortunately.

International Space Station

The ISS image above clearly shows the two large solar arrays on the space station.

What’s the problem?

Simple. It’s not a telescope…is the problem. Zoom Lenses are simply designed for a different purpose than maximum reach taking photos of planets. I’ve learned through research that the better option is to use a T-Ring adaptor and connect your DSLR to a telescope. If you’re REALLY serious you shouldn’t use a DSLR either since most have a red-light filter which changes the appearance of nebulae, you need to use a digital camera that’s specifically designed for Astrophotography (or hack your DSLR to remove it from some models if you’re crazy enough).

If you’re REALLY, REALLY interested in the best photos you can take, you need an AltAz or Altitude - Azimuth mount that automatically moves the camera in opposition to Earths rotation to keep the camera pointing in the same spot in the night sky for longer exposures. And if you’re REALLY, REALLY, REALLY serious you want to connect that to a guide scope that further ensures the auto-guided mount is tracking as precisely as possible. And if you’re REALLY, REALLY, REALLY, REALLY serious you’ll take many, many exposures including Bias Frames, Light Frames, Dark Frames, and Frame Frames and image stack them to reduce noise in the photo.

How Much Further Can You Go With a DSLR and Lenses?

Not much further, that’s for sure. I looked at adding Teleconverters, particularly the TC-14E (1.4x) and then a TC-20E (2x) which would give me an effective focal length of 1,050mm and 1,500mm respectively. The problem is that you lose a lot of light in the process and whilst you could get a passable photo at 1,050mm, with 1,500 on this lens you’re down to an aperture of f/11 which is frankly, terrible. Not only that but reports seem to indicate that coma (chromatic aberration) is pretty bad with the 2x Teleconverter coupled with this lens. The truth is that Teleconverters are meant for fast primes (f/4 or better) not a f/5.6 Zoom.

Going to an FX Camera Body wouldn’t help since you’d lose the 1.5x effective zoom from the DX sensor, although you might pick up a few extra pixels, the sensor on my D500 is pretty good in low light, so you’re not going to get a much better low-light sensor for this sort of imaging. (Interestingly the pixel density of the sensor between the D500 DX and D850 FX, leaves my camera with 6.7% more pixels per square cm so it’s still the better choice)

How Many Pixels Can You See?

Because I’m me, I thought let’s count some pixels. Picking Jupiter because it’s big, bright and easy to photograph (as planets go) with my current combination it’s 45 pixels across. Adding 1.4x Teleconverter gets me to an estimated 63 pixels, and 2.0x to 90 pixels diameter. Certainly that would be nicer, but probably still wouldn’t be enough detail to make out the red spot with any real clarity.

Just a Bit of Fun

Ultimately I wanted to see if it was possible to use my existing Camera equipment for Astronomy. The answer was: kinda, but don’t expect more than the Moon to look any good. If you want pictures somewhere between these above and what the Hubble can do, expect to spend somewhere between $10k –> $30k AUD on a large aperture, large focal length telescope, heavy duty AltAz mount, tracking system and specialised camera, and add in a massive dose of patience waiting for the clearest possible night too.

If nothing else for me at least, it’s reawakened a fascination that I haven’t felt since I was a teenager about where we sit in the Universe. With inter-planetary probes and the Hubble Space Telescope capturing amazing images, and CGI making it harder to pick real from not-real planets, suns and solar systems, it’s easy to become disconnected from reality. Looking at images of the planets in ultra-high resolution almost doesn’t feel as real as when you use your own equipment and see them with your own eyes.

So I’ve enjoyed playing around with this but not because I was trying to get amazing photographs. It’s been a chance to push the limits of the gear I have with me to see a bit more of our Solar System, completely and entirely on my own from my own backyard. And that made astronomy feel more real to me than it had for decades.

The stars, the moon, the planets and a huge space station that we humans built, are circling above our heads. All you need to do is look up…I’m really glad I took the time to do just that.

Solo Band

Apple’s new Apple Watch Series 6 was released with several new bands, of which the two most controversial are the Solo Braid and Solo Sport Loop bands. Whilst the braided band might look nice, my instant reaction was “that’s going to catch on everything” and I’ve heard a few anecdotal reports floating around the internet recently of threads being pulled on these bands as some evidence to validate my ultimate choice not to get that one.

Whilst I applaud Apple’s “Create Your Style” watch and band selector, the fact you STILL can’t select a Nike band or a Hermes band with your new watch. (I know right? No Hermes? I guess there’s always a Hermes store for that…the bands are next to the riding helmets I hear…)

Per Apple’s directions when ordering, I dutifully printed out the measuring tape/paper cutout measurement implement to find my wrist size was between 6 and 7 - exactly half way. I opted for a 7 when I ordered, plain white then attended the Chermside Apple Store to pick it up at a scheduled time through their door / COVID19 “window” for pickups.

Once in hand I opened and hastily put it on the watch and my wrist only to find it was too loose. Logic being that this was going to probably stretch over time, I went back to the “window” to swap it for a Size 6, one size down. After attempting to return just the band, and failing, then trying multiple times to return the entire watch, just to swap the band, after nearly 45 minutes I had the right fitting band and was on my way.

I’m not sure I’m complaining exactly as everything is relative. There are other parts of the world where Apple Stores are still closed due to local COVID19 lockdown restrictions, so I had it good…for sure.

Solo Loop Edge Gap

The gap at the edge is quite small and tight, which is how I like to wear my watches. (I hate loose watches)

Solo Loop on Wrist

The band to the untrained eye looks just like a traditional White Sport Band.

Solo Loop Underneath

The giveaway is underneath where there is no pin, and ultimately the reason that I like this band so much more than any of the existing sport bands. On standard two-piece sport bands, the pin isn’t so much the issue, it’s the slide-under segment through the hole that pulls out arm hairs on the way and places pressure on my carpel tunnels after many hours of wearing. (Sure I could wear it more loosely, but refer above - I hate doing that)

Feel and Comfort

The solo loop band is softer than my White Sport Band and is elastic but firm. The rubber-like texture is balanced with a smooth finish so it doesn’t grab your arm hairs too much like a rubber-band would when you take it off or put it on.

Beyond this I’ve found that like the other sport bands it’s the best option when you get it wet as it’s quick and easy to dry.

I Really Wanted A Nike Sport Loop Though

I’ve been a huge fan of my nearly two year old Blue Sport Loop band so much so that I’ve worn it more than any other band during that time and it’s frayed at the loop-back buckle and generally a bit worse for wear.

I had secretly hoped that when Apple released the Series 6 they would open up the selector to include Nike bands as options, alas they did not. So after wearing the Solo Loop for a week, I went back to the Apple Store and grabbed the band I actually wanted: the Spruce Aura Sport Loop.

Solo Loop and Sport Loop Outside

Side by side the Pure White of the Solo Loop contrasts with the subtle Green weave of the Nike Sport Loop.

Solo Loop and Sport Loop Inside

The Nike Loop is made from the same material and is just as comfortable as my previous favourite comfortable band with the bonus of being a pleasant light colour that’s reflective in the dark.

Concerns with the Solo Loops

Much has been written about the Solo Loop being a bad customer experience and certainly with so many Apple Stores not functioning as they used to due to COVID19 restrictions, finding the best fit is more difficult than it otherwise would be. That said, were they open the truly best way to get a feel for the band comfort isn’t wearing it in the store for two minutes - you really need serious time with it in general use for a few days or weeks to know for sure if it will work for you in that size.

Notwithstanding this the other issue is resale. Previously you could sell your Apple Watch or hand it down to other family members but now the variable of “will it fit their wrist” needs to be considered. If not, you’re up for another solo band that fits the recipient or one with flexible sizing that fits anyone.

If you can look past these issues, then the solo sport loop is comfortable, simple and I think better than the other Sport Bands on offer. That said…I’ll be sticking with my recommendation for the Sport Loops as the best all-round band for the Apple Watch.