External Camera Shutter Release for iOS

Black Hole

May contain traces of nut
For those who don't know, the camera shutter button on an iOS device is on-screen. That means a tap to take a picture, which also means camera shake if you are not very careful - or if you use a gentle touch, a lot of uncertainty in when the shutter will actually be triggered. The physical volume buttons can also be used to trigger the shutter, but they are not conveniently placed and also result in shake in the form of twist.

(BTW: why do people insist on using their iPhones/iPads in the vertical/portrait orientation, even when taking video? Don't they realise how stupid it looks when the resulting video is viewed on something other than a vertically-orientated phone/tablet? Also, some display methods won't rotate the output to match the orientation flag in the resulting file, so the only correct orientation for taking photos/videos on an iPhone/iPad is in landscape mode with the Home button on the right. I've even seen somebody looking at a correctly orientated - ie landscape - video on an iPhone... holding it in portrait!!!)

I decided to try adding a shutter release button to my iPad cover, positioned to make it a convenient and positive action. After all, the volume buttons on a set of earbuds work as a shutter release, right? I acquired the four-pole 3.5mm jack that connects to the earphone port, and had a play with shorting out contacts through various resistances - but nothing worked.

So I did some reading up on the matter, and discovered that Apple, in their infinite wisdom, have disabled all but straightforward audio out on the jack unless the connected device responds to a coded handshake. The Apple earbuds have a chip in them that detects a chirp tone burst from the iPhone/iPad and responds appropriately, enabling the volume control protocol and the use of the earbud volume buttons for the camera shutter control.

The alternative is a Bluetooth-connected shutter release. I gave up.

(Incidentally, for taking video, one touch on the trigger button starts recording, and the next touch stops it. How many of you have had the function out of sync, so that you are recording video when you don't want and not recording when you do? I've done it more than once, videoing my shoes instead of whatever was going on.)

Every now and again I see "selfie sticks" on sale, "no battery required". These have a wire that plugs into the headphone socket, with four poles. Read the fine print and it usually says "Android only". I went into Dunelm this morning, and there was yet another one, for £7. This one says "iPhone and Android compatible*" "* Compatible with Android 4.0 or above / Apple IOS 5.0 or above". Given what I know, I'm sceptical, but I've bought one. If it works, great - if it doesn't I can take it back.
 
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OP
Black Hole

Black Hole

May contain traces of nut
Their web site says:
iOS users:
Selfie stick is compatible with iOS 5.0 and above:

No configuration required, simply plug the cable into the audio socket and open the camera app to start taking selfies.
 

prpr

Well-Known Member
why do people insist on using their iPhones/iPads in the vertical/portrait orientation, even when taking video? Don't they realise how stupid it looks
Because seemingly most such people are, by and large, stupid.
So I did some reading up on the matter, and discovered that Apple, in their infinite wisdom, have disabled all but straightforward audio out on the jack unless the connected device responds to a coded handshake.
Does this surprise you? There was a load of stuff about replacement Home buttons being disabled by Apple during some upgrade or other a while back.
Just another reason not to buy Apple.
How many of you have had the function out of sync, so that you are recording video when you don't want and not recording when you do?
I did that some years ago. It caused a bit of hassle for my 'customer'.
I went into Dunelm this morning, and there was yet another one, for £7.
Are they purveyors of that sort of tat now as well then? I though they were basically home furnishings and suchlike.
 
OP
Black Hole

Black Hole

May contain traces of nut
Well, this is a surprise! Oh me of little faith: it works!

Needless to say, it's no longer in one piece. Here's what does it:
image.jpeg

The interesting part is what might be in the three-pin SM device labelled "XA30". A DC measurement says it looks like this:
image.jpeg

However, if I reproduce that with passive components and it doesn't work, there must be more to it than meets the eye.
 
OP
Black Hole

Black Hole

May contain traces of nut
Does this surprise you?
No, not at all. The HDMI output is also disabled unless an authorised adapter is connected to the IO port.

There was a load of stuff about replacement Home buttons being disabled by Apple during some upgrade or other a while back.
IIRC any opening of the case is detected and logged, and has to be digitally signed by an authorised technician.

Just another reason not to buy Apple.

Maybe, maybe not. For the vast majority of users it's not a problem, and helps ensure a smooth user experience (unlike the mish-mash ecosystem that is IBM-PC compatibles).

Are they purveyors of that sort of tat now as well then?
I find them very useful for materials (not just fabrics) and storage, and in general they don't stock the bargain shop tat, but there is always a bin of some mass product near the tills for impulse buys. In this case, it seems to be useful!
 
OP
Black Hole

Black Hole

May contain traces of nut
The results are in.

Q1: is the "XA30" an active device, or just a resistor network?

Q2: if it is active, does it have to be connected all the time or only to initialise the link?

I knocked up the following as a test circuit. The resistor network on the right mimics the DC measurements of the original XA30 circuit within a few tenths of a percent.

image.jpeg

With the XA30 out of circuit, the network does not trigger the camera shutter.

With the XA30 in parallel with the network, the shutter triggers when the contact closes then opens again.

With the XA30 taken out of circuit without disconnecting the circuit from the iPad, the trigger no longer works.

So: the XA30 is an active device (or at least not just a resistor network), and its properties are required constantly to maintain the function.

£7 for an iPhone holder with a swivel mount, on a sturdy telescopic handle, and fitted with this device. Not bad!

Note also that using the on-screen button to take stills results in a rapid burst of shots if the button is held instead of pressed and released. Having a remote button only takes one shot at a time (on release).

http://www.shot2go.com/selfiestick
 
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Trev

The Dumb One
At least you don't have to use a bloody smartphone as a remote shutter release as I do on my Sony camera.:frantic:.
Mind you, I also get a remote viewfinder and various other controls with that. The ap would come in useful for taking photos inside a nuclear reactor I suppose:rolling:
Suspect you need to hang a scope off it BH to find out what's really going on.
 
OP
Black Hole

Black Hole

May contain traces of nut
Suspect you need to hang a scope off it BH to find out what's really going on.
Indeed, and I am tooled up for the job when/if I get around to it. There's no real need (other than curiosity), because we now know where to get a supply of these XA30 chips. They just come in rather a lot of unnecessary packaging!

I have an RC camera trigger for my real camera, and fortunately was able to get an adapter when my camera broke and I got another one with a different electronic trigger connection (it shorts two of the USB lines together).
 
OP
Black Hole

Black Hole

May contain traces of nut
I have run a Google search for "XA30 SOT23" (the latter term describes what I believe to be the package type), and all it comes up with is a 3.0V version of the SG2010 low drop-out linear voltage regulator. I don't think that's it, because I find it very hard to see how it could function in this circuit, or match with the resistance measurements (which are the same with the meter probes either way around - indicating that the package contains a resistor network plus something active that isn't turned on by the meter test voltage).
 

MikeSh

Well-Known Member
(which are the same with the meter probes either way around - indicating that the package contains a resistor network plus something active that isn't turned on by the meter test voltage).
Or something like a pair of diodes in reverse parallel?
 
OP
Black Hole

Black Hole

May contain traces of nut
Why "or"? Your proposal makes sense without the "or", but not with it.

I may find out in the fullness of time. The only reason I have to doubt it is what I have read before about the "chirp" negotiation.
 

MikeSh

Well-Known Member
Why "or"? Your proposal makes sense without the "or", but not with it.
You said "indicating that the package contains a resistor network plus something active ...". I said "Or" because I was suggesting an alternative to that combination, not just the active bit. Ie. (a resistor network plus something active) OR (a pair of diodes in reverse parallel). I don't know if the resistance tests you've done would have indicated that there are definitely resistors involved.

But I'd tend to agree that there is probably something more active involved in the 'chirp'.
 
OP
Black Hole

Black Hole

May contain traces of nut
No, the resistance measurements are solid. If there are active components involved (including diode junctions) they are in parallel with the measured resistances. Semiconductor junctions would result in bias currents, even at excitation voltages below the normal turn-on voltage, and result in asymmetric measurements. The values I measured are symmetric to fractions of a tenth of a percent.
 

Scrat

Definitely contains acorns
For those of you with more sense, use your tablet as a remote control for your REAL camera. You also get to see the preview on your tablet screen.

Sony do an app for this, I am sure other manufacturers do too.
 
OP
Black Hole

Black Hole

May contain traces of nut
There is a conflict of opinion there:
At least you don't have to use a bloody smartphone as a remote shutter release as I do on my Sony camera.:frantic:.
Mind you, I also get a remote viewfinder and various other controls with that. The ap would come in useful for taking photos inside a nuclear reactor I suppose:rolling:

...but that was never the point of this topic.
 
OP
Black Hole

Black Hole

May contain traces of nut
£7 for an iPhone holder with a swivel mount, on a sturdy telescopic handle, and fitted with this device. Not bad!
As an addendum, note that I have seen what appear to be very similar selfie sticks much cheaper in the likes of B&M (I can't remember exactly where) in the intervening time since the OP. I saw them again in Dunelm yesterday, still for £7.
 

Scrat

Definitely contains acorns
At least you don't have to use a bloody smartphone as a remote shutter release as I do on my Sony camera.
Mind you, I also get a remote viewfinder and various other controls with that. The ap would come in useful for taking photos inside a nuclear reactor I suppose.
Suspect you need to hang a scope off it BH to find out what's really going on.

At least you have a proper camera rather than the microscopic sensor in phones! Some Sony cameras accept a remote release, others only a smartphone or tablet. If you can reach the camera (not outside taking wildlife photos, with you indoors) you can often just set a timer delay to minimise vibrations.

Phone cameras are the nadir of mediocrity, low sensor ability, masses of post processing, crop zoom, artificial blur, photography for the non discerning masses to cram their twitface feeds and forget about. Does that sound elitist? Photography is a lowbrow hobby at best, why make it even less capable?
 

Scrat

Definitely contains acorns
I don't think that David Bailey or Lord Snowdon would agree with you, if you'll excuse my trip back into the last century.

They wouldn't though, would they? I don't suppose Bowie and Prince would have thought their music was cr*p either, doesn't make it any less so.
 
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