TL;DR – WiFi on cameras is crap because cameras have low performance processors and low performance WiFi modules and the interface between the two is slow. On top of that software is very lacking. No, it does not look like it will change in the near future.
The WiFi connection on most dedicated cameras sucks big time. It is slow, terribly slow. And it seldom lacks automation: I have not found any DSLR/MILC camera that can pair with an app on your computer and whenever both are in range of WiFi you can have the pictures automatically transferred in the background without any intervention. And when the automation is there, is is highly unreliable.
Just think how easy it is to get photos taken from your phone to be on you PC by using any of the numerous cloud services. There must be years since I hooked up my phone to my computer with a cable to download a picture.
My own experience I have dealt with cameras from the 250 euro EOS M10 to expensive items in the 1000-2000 range like the Nikon D7500, Nikon Z5 and Sony A6400. None have usable WiFi.
What I want and what I get
Scenario 1: go out and take few pictures. Ideally, when I come back, my camera will find the WiFi network, find my computer and upload the pictures without me having to get it out of the bag. Scenario 2: I go on holiday and I can pair the camera to my phone over WiFi so all pictures land in my phone automatically. This works for backup and as a simple way to avoid taking a picture with the phone just so I have a way to send it.
- In both cases, the data should be transferred automatically when possible, but this does not work. Many cameras don’t do any automated stuff, and the one I have that supports that (Nikon Z5) does not work reliably.
- In both cases, i want the data to be transferred reasonably fast, take not more than a couple of seconds per full size image. In reality most cameras can barely do 1-3 MBps, resulting in times as long as 30 seconds for an image.
- I also want this to be energy efficient, a full battery should be able to transfer many thousands of images, but in practice I can barely get a few hundred from a charge.
Its a common problem and a vicious circle
The problem is common, not just for the models I mentioned. I have done a lot of searching for a camera for both me and a couple of other people who wanted the same thing and there is none, at leas in the sub 2000 EUR price.
The situation seems to create a vicious circle: without speed and automation, WiFi on cameras is so bad that people don’t use it. And because people don’t use it, manufacturers think they don’t have to invest in it so it sucks. It ends up being just a label on the camera box about a feature that nobody uses.
I am sure most people, especially amateurs, would prefer an automated, set-and-forget system that delivers the pictures from the camera without intervention, reliably and with good speed and efficiency. Until that is achieved, WiFi on cameras is just a bad joke of a feature the manufacturers
Its possible to have it better – Phones, laptops
With my current camera I barely get a bit over 1MBps, so let’s be generous and say the data rate is 10Mbps (notice the B and b difference). My laptop’s WiFi 6 card supports up to 2400Mbps or 240X faster. My phone can do 800Mbps, or 80X faster. So there is plenty of room for improvement!
Why is it so bad though ?
Finding out why things are bad was not so easy. You my think it is just cheap and uninterested manufacturers, but I was not happy with this answer.
The camera processor
So I started digging around to understand how cameras are build and what is inside. One of the most interesting components is the processor. If you think that is a rather standard part that you might find in a computer, you are wrong. The camera manufacturers have different names for them Expeed, Digic, Bionz etc and what is inside is a closely guarded secret. But we can get some pieces of information from around the internet.
The processors in cameras are not generic processors because processing so much data from the sensor one operation at a time, would require massive general purpose processors to do in a short amount of time. Instead, they use complicated SoCs (system on chip) which contain a lot dedicated hardware which is specialized at doing some operations in a parallel and fast way. Specific information is sparse, but rumors are that the Nikon Expeed processors used to be made by Fujitsu and called Milbeaut. Here’s what is inside one of the earliest ones called M4 from 2005, aimed at SLR cameras. Possibly what was in my old Nikon D90.
Here is a bit of explanation of what is inside: the left half of the block diagram contains dedicated hardware functions for processing images and turning the data from the sensor into images that can end up in the SDRAM memory (top, external) and then in the media card (top right). The bottom right section is dedicated to displaying information on the external screen and camera LCD.
And sandwiched there somewhere in the middle of the right side is the CPU (FR80) 132 MHz bloc which is the general processor. The CPU is likely a general purpose FR80 RISC processor which runs software from the NOR flash memory of the camera. The CPU is the conductor of the whole system and reads the buttons and instructs the whole SoC what to do, like take a picture, process it, store it in the RAM and then move it in the memory card. But because everything intensive happens in the dedicated hardware, the CPU is rather weak, only 132 MHz.
Just to give you an idea, 2005, the same year this was made saw the introduction of the first dual core processors for computers running at 2.4 GHz. So very roughly speaking, the processor in the camera is about 36 times less powerful than a contemporary computer processor.
It is very likely this trend has continued and the situation is valid for current cameras: the processing is done in a SoC which contains dedicated hardware for the imaging processing functions and low performance processor for controlling everything.
The camera WiFi
Next I tried to find what sort of WiFi chips are there in cameras. Teardowns are hard to find, after all, cameras are expensive things which are hard to disassemble and assmeble again. My search is based on the very beautiful Nikon Z6 and Nikon Z7 teardown photographs. The WiFi module on the Z7 is more clearly visible in one of the pictures, it’s the white rectangle and the cable is going to the antenna somewhere else. Here is a crop:
Image source: https://kolarivision.com/nikon-z7-dissasembly-teardown/
The SS8510012 written on it is not a part number, but the M logo indicates this is a Murata WiFi and Bluetooth module. I dug through some datasheets and the SSxxxx seems to be how the serial number is labelled on the modules. I don’t know if the part number is missing because Nikon asked for it to be removed or if it is just removed in the photographs in the teardown.
WiFi modules are subsystems themselves, which contain their own processor, memory and radios and have code running on them. That way they can offload the complicated intricacies and real time operation of WiFi and Bluetooth and allow the main processor in the system to deal only with high level data exchanged over the interface.
Digging though the product list of Murata it is clear they have 2 types of modules: (1) low performance and low power ones intended for IoT applications which interface via SDIO or SPI and (2) higher performance modules which interface via PCIe.
I strongly suspect that its the low performance WiFi modules which are present on cameras. That means the data transfer between the module and the camera is likely one of the bottlenecks: those based on SPI can reach some MHz, the modules based on SDIO seem to be topped at 25MHz (x4 = 100Mbps). This means there is first a bottleneck in the WiFi speed is the communication between the camera and the WiFi module and then all other inefficiencies can justify the speed observed in WiFi transfer of only a few MBps. Bummer.
The camera software
Another aspect that is missing is a proper automation in the camera software so that the camera can automatically transfer the pictures. By automatically i mean the camera should keep track of files which have been uploaded and which not and try to upload them whenever possible. This has to be done in an energy efficient way, so the camera must be smart and use WiFi only when it needs it. Many cameras only have a manual mode, where you have to manually turn on the WiFi and manually connect the other device and manually send some pictures.
In some way, I understand the camera manufacturers not pushing to have this automation – the transfer speed is atrociously bad, so there is no point to invest in this. Nobody wants to wait half a minute to transfer a picture. In some other way, there is the proposed idea that the Japanese are not that into software development.
Unless the automation works flawlessly, I have no use for it, because I am always faster just popping the card out and into the card reader of the laptop of phone.
Is there any fix (soon) ?
Most likely not. As long as cameras sales continue to decline, I highly doubt camera makers are going to focus on improving the WiFi. They need to make money selling you what they have sold you for decades: lenses and sometimes cameras.
To get the WiFi to be useful (=faster and automated), cameras need to be overhauled in 3 ways:
- Get the main processor in the camera to be more powerful and provide a PCIe interface. This is a cost they don’t need.
- Use a more powerful and more expensive WiFi module. Another cost they don’t need now.
- Develop very good automation software. Software costs money.
I highly doubt this is a priority for camera manufacturers*. Especially since some of them have uberly expensive external WiFi boxes that are actually fast.
*I am of course talking about interchangeable lens camera manufacturers. Other camera manufacturers do have better wifi.
For now I have no use for the WiFi function of my cameras. Without automation, I am forced to take manual steps. Combined that with the terribly slow speed means that its always faster to just pop the card out and into the computer (when i get home) or into the phone when I am travelling and want to backup the pictures.
If WiFi would work well, I think it is more useful than having a dual card slot because everyone has a smartphone in their pocket now.
Bluetooth is rather good already
For now I am still using the bluetooth function of my Z5 and D7500: it can sync the time and location from the phone and automatically transfer low resolution, 1.7Mpix, pictures automatically.
Again, the software is lacking: it took a few years before Nikon made this work automatically and reasonably reliable. Reasonably. But it is still lacking in features: does not let you choose higher resolution which I want and it cannot support multiple cameras at the same time.
What about other cameras?
I stuck here to interchangeable lens cameras, mainly SLRs and MILC cameras from the typical manufacturers. It might apply to compact/bridge cameras as well. The WiFi aspect seems to be a common problem for them. Other camera types (action cameras, drones) might actually have a much higher WiFi transfer speed. I did not search everywhere, but there does not seem to be a model that couples automation with speed.
Do you have more links about insides of cameras or details about various parts inside? Please share!
Nikon Z7 teardown https://kolarivision.com/nikon-z7-dissasembly-teardown/
Nikon Z6 teardown https://kolarivision.com/nikon-z6-disassembly-teardown
Nikon expeed made by fujitsu https://www.dpreview.com/forums/post/52291309
Canon DIGIC https://en.wikipedia.org/wiki/DIGIC
Nikon Expeed https://en.wikipedia.org/wiki/Expeed
Sony Bionz https://en.wikipedia.org/wiki/Bionz
Murata product lineup https://www.murata.com/products/connectivitymodule/wi-fi-bluetooth
WiFi reports for various cameras
This list is far from complete, I searched far and wide before buying my Z5 to see if similarly priced cameras can handle WiFi well, but none that i found could.
A 7RIV 4 – 9 MBps speed https://www.dpreview.com/forums/post/63148137
Z7 2-3 MBps https://www.dpreview.com/forums/thread/4344981
Arguably, Nikon perpetuates this ‘feature omission’ to protect the sales of its separate ($1000) WT-7 transmitter to a handful of folk. https://www.dpreview.com/forums/thread/4321025