Camera trigger circuit works with Canon but not with Nikon cameras

I have this simple circuit to control the camera shutter and focus. R1 & R2 are 270 Ohm.

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It works fine with my Canon dSLR camera but not with the Nikon D7100. On the Nikon only the focus works, the shutter does not.

Any ideas how to make it work with both cams?

Do you have an adaptor cable as the schematic you posted is for a jack socket but the D7100 seems to use a proprietary connector. If you have the adaptor cable then buzz out the pins to see where Focus, Shutter & Ground go on the jack socket the other end.

I have an adaptor cable for the Nikon that has a 2.5mm jack on one end and a Nikon plug on the other.

I have tested the cable with another remote and it works. It also triggers the shutter if I manually short the shutter & common sections on the 2.5mm jack.

I tested the circuit with two more cameras, a Fuji and a Sony a6000 with corresponding adaptor cables. With the Fuji the shutter works with the Sony it doesn't.

Focus works with all cameras.

You have a schematic drawing and a Fritzing image in your first post but they do not match each other, so what what one have you wired it like? The schematic uses pin 4 as common and the Fritzing image uses pin 5 as common. Are you using a 4N35TM Optocoupler or something different?

sorry, the schematic is what I'm using, I removed the fritzing, the optocoupler is a 4N35

Plan B:

Arduino Yun/Yun Shield with Gphoto2

It can control the camera far more than only shutter and focus. It supports more than 2100 cameras.

http://www.gphoto.org/proj/libgphoto2/support.php

I'd like to keep things simple with a basic circuit that works even with the tiny.

I wonder why the optocoupler works for some cams and not for others, maybe a reed relay would be a universal solution.

Brav0: sorry, the schematic is what I'm using, I removed the fritzing, the optocoupler is a 4N35

Try wiring it up the same way as the Fritzing image instead (common pin 5 & pin 4 as emitter output) and see if that works. As the opto coupler switch is a transistor you need to connect the VCC and GND the right way round to the collector & emitter pins. Maybe the Nikon cable works this opposite way round to the Cannon cable.

The opto on its own might not be quite enough to drive everything. Try adding a transistor (2N2222 or equivalent) on the output like this:

Pete

P.S. or get an optoisolator with a Darlington output so that you don’t have to add any more external components.

Pete

thanks for the tip, I'll try an optocoupler with Darlington output, any particular model no you can suggest? I did a search and found serveral.

If I remember correctly Nikons, as opposed to Canons, require both focus and shutter to be activated for the shutter to work.

The one I used was a TIL 119 but that was a long time ago and it is now obsolete.

Pete

Now that Shpaget has mentioned it, I checked my ancient code which I used to control a Canon EOS 10D with a Sony IR remote. When FOCUS is selected, only the focus line is asserted. When SHUTTER is selected, it asserts the focus line for 25ms and then asserts the shutter line. Now that I think about it, that is how the Canon wired remote works. Pushing the button down partway asserts focus and pushing it all the way down also asserts shutter at the same time. @Brav0 - can you post your code?

Pete

I just found another page where it says the same as Shpaget (all the way to the bottom).

Here's the simple testing code I use:

int shutter = 4;
int focus = 5;

void setup() {
 pinMode(shutter, OUTPUT);
 pinMode(focus, OUTPUT);
}

void loop() {

 //focus
 digitalWrite(focus, HIGH);
 delay(300);
 digitalWrite(focus, LOW);
 delay(1000);

 //shoot
 digitalWrite(shutter, HIGH);
 delay(300);
 digitalWrite(shutter, LOW);
 delay(5000);

}

Try this for shooting:

 //shoot
 digitalWrite(focus, HIGH);
 delay(25);
 digitalWrite(shutter, HIGH);
 delay(300);
 digitalWrite(shutter, LOW);
 digitalWrite(focus, LOW);
 delay(5000);

The 300ms holding both high should be enough, but if not give 500 a try.

Pete

Another thing that is worth mentioning, if the lens is in autofocus mode the camera will not activate the shutter if the lens can't find focus. That also means that focus "button" has to be pressed for long enough to allow the lens to lock on. Depending on lens, body and light conditions and object in question, that can take quite a while. For the testing purposes the combined focus + shutter time should be at least a few seconds. Also test with turning the autofocus off.

For standard operation though, I would advise you to put the lens in a manual focus mode to ensure the camera takes the picture. Prefocus to a distance where you expect the object to be.

Thanks so much, it works now. Focus must be active for the shutter to fire on Nikon & Sony cams.

Shpaget: Another thing that is worth mentioning, if the lens is in autofocus mode the camera will not activate the shutter if the lens can't find focus. That also means that focus "button" has to be pressed for long enough to allow the lens to lock on.

Searching this stuff for my own project. You can change the shutter release priority:

Nikon Menu setting A2 "AF-S Priority selection": you can change this to priorities releasing the shutter, but for your application you would be better off pre-focusing if you aren't going to give a time-delay for focusing.