Build a shutter tester for Focal Plane shutters - Cheap, Easy & it Works

Jchick said:

I uploaded the new sketch and am having an issue or two. The serial monitor is showing really weird symbols instad of the read out. See photo below. The LCD is showing the below info for a shutter speed of 1/60. Laser 2 is always 1/54 and laser 1 fluctuates between 1/676 and 1/712. The other LCD screen photo is from a test at 1/125s. It shows 1/107 and 1/718. Can someone interpret this for me? View attachment 345762View attachment 345760View attachment 345759

Click to expand...

Hi,

Sorry you are having difficulties.

As posted above, there is a test code to determine new & old laser type.
I think full details of it's use are posted in the original post.
(The ESP32 version has this built in & will automatically set the receiver type).

For the code I uploaded a few days ago, you have to change the baud rate on your serial monitor to 115200
Sorry, did not think of this. the default is 9600, but setting it to 115200 is so much faster. (On the ESP32 version, it is even faster and the text appears instantly).

As for your strange readings, some things to try.

Check the wiring & ensure receiver 1 is on the right, as viewed from behind the camera.
Make a shutter-tester-tester ) I use this for testing. Get a sheet of card and cut a slot in it, about 2cm wide. Cut it at the edge of the card, but in the middle. This way you can move the card from right to left across the lasers and it will act like the slot in the shutter curtains. The card either side of the slot will mask the lasers, so only move the card so the slot moves past both lasers and stop so the remaining card again blocks the lasers.
Saves having to keep re-cocking the camera shutter.


Try using single laser mode. Ensure laser 2 is covered and then align the camera so just one laser goes through the shutter opening. You can also use a card to simulate the shutter opening & closing.
The SW should detect that laser 2 is not triggered and only laser 1 results should be displayed.


The boxes you are using are quite reflective. Maybe stray laser light is being bounced around. The lego version had a problem with inaccurate results and after the use of a mask, now works perfectly.

Try making a mask out of matt black card, to cover the front of the boxes. Cut two small holes for the lasers to shine though.


In the top right of the LCD it says 'Bou' this is indicating that shutter bounce is being detected. This is when the second curtain closes, but the force is so great, it bounces open again before closing.

This could also be an indication that stray light or laser light is bouncing around, as laser 2 receiver is reporting that it is being triggered more than once per shutter cycle. (Normally when the second curtain closes, bounces open and closes again)


Whist the receivers are more sensitive to laser light wavelengths, they can be affected by strong ambient light, so try in a darkened room & where no light is shining directly onto the tester.

If ambient or bouncing light is the issue, a small redesign of your tester, to put the receivers on the back wall of the box would solve this, maybe with the inside of the box painted black. This is how I will eventually make my tester & also have the lasers recessed into the box.


Please let us know how you get on.

Regards,

Niglyn said:

Try making a mask out of matt black card, to cover the front of the boxes. Cut two small holes for the lasers to shine though.

Click to expand...

I think it would be difficult to make neat holes around 1mm or less in paper card. I used plastic sheet, sold in model shops as ‘Plasticard’, in which you can make clean holes with a twist drill.

So i changed the baud and restarted everything. It seems to be working. I tested the shutter on an AE-1. From 1 second to 1/30 it is spot on. At 1/60 it starts to lose speed. Here are the readings....
1/60s - 1/54
1/125 - 1/109
1/250 - 1/200
1/500 - (L1)1/317-(L2)1/359
1/1000 - (L1)1/446-(L2)1/530

Is this a camera issue or a tester limitation?

Update - tested another AE-1. Same thing with slower speeds to 1/60.

Jchick said:

So i changed the baud and restarted everything. It seems to be working. I tested the shutter on an AE-1. From 1 second to 1/30 it is spot on. At 1/60 it starts to lose speed. Here are the readings....
1/60s - 1/54
1/125 - 1/109
1/250 - 1/200
1/500 - (L1)1/317-(L2)1/359
1/1000 - (L1)1/446-(L2)1/530

Is this a camera issue or a tester limitation?

Update - tested another AE-1. Same thing with slower speeds to 1/60.

Click to expand...

I think it’s a hole diameter issue. If you think about it, having large holes will mean the receiver makes contact with the light beam sooner, and looses it later. So the device will tend to overestimate the duration of exposure. When the curtain slit is very narrow, as with 1/500 and 1/1000, the ‘fringe’ exposure will be large relative to the real exposure. Reducing hole size definitely helps with this, but there comes a point where the errors measured are within expectations and the device can be pronounced ‘good enough’. That’s my current understanding anyway!

snusmumriken said:

I think it’s a hole diameter issue. If you think about it, having large holes will mean the receiver makes contact with the light beam sooner, and looses it later. So the device will tend to overestimate the duration of exposure. When the curtain slit is very narrow, as with 1/500 and 1/1000, the ‘fringe’ exposure will be large relative to the real exposure. Reducing hole size definitely helps with this, but there comes a point where the errors measured are within expectations and the device can be pronounced ‘good enough’. That’s my current understanding anyway!

Click to expand...

Did anybody perhaps did some testing on what hole size is best? Is it the smaller the better, or is there a point where the hole is too small?

canaq said:

Did anybody perhaps did some testing on what hole size is best? Is it the smaller the better, or is there a point where the hole is too small?

Click to expand...

I would guess that it’s a trade-off between measurement accuracy and whether the receiver can detect the restricted beam at all. But in my case, I don’t have the patience to test beyond the ‘good enough’ point.

Jchick said:

So i changed the baud and restarted everything. It seems to be working. I tested the shutter on an AE-1. From 1 second to 1/30 it is spot on. At 1/60 it starts to lose speed. Here are the readings....
1/60s - 1/54
1/125 - 1/109
1/250 - 1/200
1/500 - (L1)1/317-(L2)1/359
1/1000 - (L1)1/446-(L2)1/530

Is this a camera issue or a tester limitation?

Update - tested another AE-1. Same thing with slower speeds to 1/60.

Click to expand...

What do you mean by limitation?
There should be no limitation of the shutter tester.
I don't understand the readings you have posted.

snusmumriken said:

I would guess that it’s a trade-off between measurement accuracy and whether the receiver can detect the restricted beam at all. But in my case, I don’t have the patience to test beyond the ‘good enough’ point.

Click to expand...

I think people are getting hung up on hole size. Unless you can get a single photon size beam, there will always be some width of a beam.
Look at a commercial tester from the 70s or 80s.. They use old logic, a massive collimated light source and a photo-transistor behind a slot.

The suggestion to use a piece of black card, was to minimise reflection rather than to limit beam width.

When I was making the tester, I also used an oscilloscope to measure shutter time. This gave me the same results as the Arduino based tester. My camera goes to 1/1000s and the tester worked fine at that speed.

Sorry I wasn't clear. I was in a hurry before. The limitation comment was based on previous comments about beam size but what you just explained makes sense. I will try the black card, non-relflective idea and see if that changes anything. In the meantime, I ran the Canon AE-1 through all shutter speeds and this is what I got on the serial monitor. Everything up to 1/60 reads accurately. After that you can see where it slows down. It is reading half speed at 1/1000. I guess I am hoping that I did something wrong so I dont have to take this thing apart and do a CLA. If it is in fact my camera, do any of you have a link you can share that will help me learn how to fix the issue? Thank you for being patient with my questions! This has been a really fun process for me.

1s
PARAMETER LASER2 LASER1
Shutter Speed MicroS 1043016 1042872
Shutter Speed milliS 1043 1043
Shutter Speed Seconds 1.043 1.043
Shutter Speed Fraction
Curtain Travel MicroS 12124 11980
Curtain Travel MilliS 12 11
AVERAGES LASER2 LASER1
shutter Speed Av mS 6 1043 309
Curtain Travel Av mS 5 323 11348
Shutter Speed Av Vul 6 1.04 1/3
shutter Speed Min mS 6 513 -8853
shutter Speed Max mS 6 2105 7044
shutter Speed St Dev 6 649.93 5161.47
Curtain Travel St Dev 5 465.51 465.51


1/2s
PARAMETER LASER2 LASER1
Shutter Speed MicroS 511780 511684
Shutter Speed milliS 512 512
Shutter Speed Seconds 0.512 0.512
Shutter Speed Fraction 1/2 1/2
Curtain Travel MicroS 12144 12048
Curtain Travel MilliS 12 12
AVERAGES LASER2 LASER1
shutter Speed Av mS 7 955 338
Curtain Travel Av mS 6 271 9459
Shutter Speed Av Vul 7 0.95 1/3
shutter Speed Min mS 7 512 -8853
shutter Speed Max mS 7 2105 7044
shutter Speed St Dev 7 620.48 4712.38
Curtain Travel St Dev 6 435.31 435.31

1/4s
PARAMETER LASER2 LASER1
Shutter Speed MicroS 258132 258040
Shutter Speed milliS 258 258
Shutter Speed Seconds 0.258 0.258
Shutter Speed Fraction 1/4 1/4
Curtain Travel MicroS 12136 12044
Curtain Travel MilliS 12 12
AVERAGES LASER2 LASER1
shutter Speed Av mS 8 855 328
Curtain Travel Av mS 7 234 8109
Shutter Speed Av Vul 8 0.86 1/3
shutter Speed Min mS 8 258 -8853
shutter Speed Max mS 8 2105 7044
shutter Speed St Dev 8 624.66 4362.91
Curtain Travel St Dev 7 409.30 409.30

1/8s
PARAMETER LASER2 LASER1
Shutter Speed MicroS 129516 129404
Shutter Speed milliS 130 129
Shutter Speed Seconds 0.130 0.129
Shutter Speed Fraction 1/8 1/8
Curtain Travel MicroS 12136 12024
Curtain Travel MilliS 12 12
AVERAGES LASER2 LASER1
shutter Speed Av mS 9 765 306
Curtain Travel Av mS 8 206 7097
Shutter Speed Av Vul 9 0.76 1/3
shutter Speed Min mS 9 130 -8853
shutter Speed Max mS 9 2105 7044
shutter Speed St Dev 9 632.62 4081.67
Curtain Travel St Dev 8 387.00 387.00

1/15s
PARAMETER LASER2 LASER1
Shutter Speed MicroS 64992 64848
Shutter Speed milliS 65 65
Shutter Speed Seconds 0.065 0.065
Shutter Speed Fraction 1/15 1/15
Curtain Travel MicroS 12172 12028
Curtain Travel MilliS 12 12
AVERAGES LASER2 LASER1
shutter Speed Av mS 10 687 282
Curtain Travel Av mS 9 185 6310
Shutter Speed Av Vul 10 0.69 1/4
shutter Speed Min mS 10 65 -8853
shutter Speed Max mS 10 2105 7044
shutter Speed St Dev10 636.06 3848.98
Curtain Travel St Dev 9 367.76 367.76

1/30s
PARAMETER LASER2 LASER1
Shutter Speed MicroS 34336 34212
Shutter Speed milliS 34 34
Shutter Speed Seconds 0.034 0.034
Shutter Speed Fraction 1/29 1/29
Curtain Travel MicroS 12160 12036
Curtain Travel MilliS 12 12
AVERAGES LASER2 LASER1
shutter Speed Av mS 10 622 -419
Curtain Travel Av mS 10 168 5680
Shutter Speed Av Vul 10 1/2 -0.42
shutter Speed Min mS 10 34 -8853
shutter Speed Max mS 10 2105 7044
shutter Speed St Dev10 634.23 3032.22
Curtain Travel St Dev10 351.02 351.02

1/60s
PARAMETER LASER2 LASER1
Shutter Speed MicroS 18328 18280
Shutter Speed milliS 18 18
Shutter Speed Seconds 0.018 0.018
Shutter Speed Fraction 1/55 1/55
Curtain Travel MicroS 12076 12028
Curtain Travel MilliS 12 12
AVERAGES LASER2 LASER1
shutter Speed Av mS 10 413 -628
Curtain Travel Av mS 10 168 5680
Shutter Speed Av Vul 10 1/2 -0.63
shutter Speed Min mS 10 18 -8853
shutter Speed Max mS 10 2105 7044
shutter Speed St Dev10 387.08 2908.47
Curtain Travel St Dev10 351.02 351.02

1/125s
PARAMETER LASER2 LASER1
Shutter Speed MicroS 9120 9248
Shutter Speed milliS 9 9
Shutter Speed Seconds 0.009 0.009
Shutter Speed Fraction 1/110 1/108
Curtain Travel MicroS 11924 12052
Curtain Travel MilliS 11 12
AVERAGES LASER2 LASER1
shutter Speed Av mS 10 310 258
Curtain Travel Av mS 10 63 12
Shutter Speed Av Vul 10 1/3 1/4
shutter Speed Min mS 10 9 -8853
shutter Speed Max mS 10 2105 7044
shutter Speed St Dev10 334.61 339.28
Curtain Travel St Dev10 162.26 162.26

1/250s
PARAMETER LASER2 LASER1
Shutter Speed MicroS 4952 5260
Shutter Speed milliS 5 5
Shutter Speed Seconds 0.005 0.005
Shutter Speed Fraction 1/202 1/190
Curtain Travel MicroS 11676 11984
Curtain Travel MilliS 11 11
AVERAGES LASER2 LASER1
shutter Speed Av mS 10 259 259
Curtain Travel Av mS 10 12 12
Shutter Speed Av Vul 10 1/4 1/4
shutter Speed Min mS 10 5 -8853
shutter Speed Max mS 10 2105 7044
shutter Speed St Dev10 338.82 338.86
Curtain Travel St Dev10 0.42 0.42

1/500s
PARAMETER LASER2 LASER1
Shutter Speed MicroS 2748 3184
Shutter Speed milliS 3 3
Shutter Speed Seconds 0.003 0.003
Shutter Speed Fraction 1/364 1/314
Curtain Travel MicroS 11544 11980
Curtain Travel MilliS 11 11
AVERAGES LASER2 LASER1
shutter Speed Av mS 10 208 208
Curtain Travel Av mS 10 12 12
Shutter Speed Av Vul 10 1/5 1/5
shutter Speed Min mS 10 3 -8853
shutter Speed Max mS 10 2105 7044
shutter Speed St Dev10 334.64 334.67
Curtain Travel St Dev10 0.48 0.48

1/1000s
PARAMETER LASER2 LASER1
Shutter Speed MicroS 1900 2312
Shutter Speed milliS 2 2
Shutter Speed Seconds 0.002 0.002
Shutter Speed Fraction 1/526 1/433
Curtain Travel MicroS 11544 11956
Curtain Travel MilliS 11 11
AVERAGES LASER2 LASER1
shutter Speed Av mS 10 104 104
Curtain Travel Av mS 10 12 12
Shutter Speed Av Vul 10 1/10 1/10
shutter Speed Min mS 10 2 -8853
shutter Speed Max mS 10 2105 7044
shutter Speed St Dev10 164.69 164.67
Curtain Travel St Dev10 0.52 0.52

Here are the readings for 1/500 and 1/1000s from another AE-1. They are showing a huge gap between shutter speed fractions. What does that mean?

1/1000s
Shutter Speed MicroS 1408 2028
Shutter Speed milliS 1 2


Shutter Speed Seconds 0.001 0.002
Shutter Speed Fraction 1/710 1/493


Curtain Travel MicroS 11452 12072
Curtain Travel MilliS 11 12


AVERAGES LASER2 LASER1
shutter Speed Av mS 10 103 103
Curtain Travel Av mS 10 11 12


Shutter Speed Av Vul 10 1/10 1/10


shutter Speed Min mS 10 1 -8853
shutter Speed Max mS 10 28864 28572


shutter Speed St Dev10 165.28 165.18
Curtain Travel St Dev10 0.42 0.42


1/500s
Shutter Speed MicroS 2348 2964
Shutter Speed milliS 2 3


Shutter Speed Seconds 0.002 0.003
Shutter Speed Fraction 1/426 1/337


Curtain Travel MicroS 11432 12048
Curtain Travel MilliS 11 12


AVERAGES LASER2 LASER1
shutter Speed Av mS 10 205 205
Curtain Travel Av mS 10 11 12


Shutter Speed Av Vul 10 1/5 1/5


shutter Speed Min mS 10 2 -8853
shutter Speed Max mS 10 28864 28572


shutter Speed St Dev10 329.62 329.50
Curtain Travel St Dev10 0.42 0.42

which laser module is the code written for? Or actually even with some phototransistor like BPW76b should work?

Sorry if is too basic but I didnt touch any arduino since before the pandemic, I'm a bit rust. But I still have some of them and even an OLED display, so just with the laser/photodiode should be good to go.

canaq said:

Did anybody perhaps did some testing on what hole size is best? Is it the smaller the better, or is there a point where the hole is too small?

Click to expand...

The same sensors are specified for the so called “Film Camera Tester” and 0.8mm gives accurate results.

I had posted earlier that the entire film plane module (pc board and 3d files) for that tester can be used on the hardware presented in this thread.

Neofito said:

which laser module is the code written for? Or actually even with some phototransistor like BPW76b should work?

Sorry if is too basic but I didnt touch any arduino since before the pandemic, I'm a bit rust. But I still have some of them and even an OLED display, so just with the laser/photodiode should be good to go.

Click to expand...

It was written for the new laser module. I think it is my cameras. I was able to lubricate both cameras and it fixed the shutter speed issue on one of them. So it looks like i need to do a full CLA on one of them.

Today I finally had some time to work on my project, so here are two pictures of my creation. It's not finished yet, the laser and receiver will go inside the grey boxes, but are now temporarily mounted on top with some blu tack. I also used an old cutting board and some pieces of wood from an old stacking game.

The whole project is standalone, I have mounted a battery unit on the bottom. Cable management on the bottom is also on the to-do list

Thanks everybody for the help!

Jchick said:

It was written for the new laser module. I think it is my cameras. I was able to lubricate both cameras and it fixed the shutter speed issue on one of them. So it looks like i need to do a full CLA on one of them.

Click to expand...

ok, found it https://www.ebay.de/itm/29512722682...krWYMWCTWG&var=&widget_ver=artemis&media=COPY

anyway I am gonna buy one phototransistor to build the sensor for the smartphone app, I am curious to compare results and also which one is easier to use on daily base.

canaq said:

Today I finally had some time to work on my project, so here are two pictures of my creation. It's not finished yet, the laser and receiver will go inside the grey boxes, but are now temporarily mounted on top with some blu tack. I also used an old cutting board and some pieces of wood from an old stacking game.

The whole project is standalone, I have mounted a battery unit on the bottom. Cable management on the bottom is also on the to-do list

Thanks everybody for the help!

Click to expand...

Very nice build! Have you added a further voltage regulator to cater with the falling voltage over time from the batteries? Or are you relying on the onboard VR of the Arduino?

Neofito said:

which laser module is the code written for? Or actually even with some phototransistor like BPW76b should work?

Sorry if is too basic but I didnt touch any arduino since before the pandemic, I'm a bit rust. But I still have some of them and even an OLED display, so just with the laser/photodiode should be good to go.

Click to expand...

Hi,
The standard arduino modules were used for simplicity. The lasers themselves can be bought from aliexpress with wire tails.
The receiver sensor is clever, as rather than just a photo-diode, it incorporates an amplifier & Schmitt trigger. It is also very insensitive to anything but the laser wavelength, so can be used without having to dim the lights.
A photo resister is too slow to give good results. No reason not experiment with a photo-diode, just be sure to limit the current with the appropriate resister. The arduino input just looks for a high/low change. This has to be snappy & decisive, which is why the Schmitt trigger works well.

Please keep us updated with your experimentation.

Neofito said:

ok, found it https://www.ebay.de/itm/29512722682...krWYMWCTWG&var=&widget_ver=artemis&media=COPY

anyway I am gonna buy one phototransistor to build the sensor for the smartphone app, I am curious to compare results and also which one is easier to use on daily base.

Click to expand...

Hi, using one sensor is pointless. I was fed up with seeing designs using just one sensor, or using audacity, so I posted my cheap simple -but works shutter tester here, for the world to build )

Youtube has a number of good slomo videos showing how focal plane shutters work. Once it is understood how a focal plane shutter works with two curtains, it will be understood that both curtains need to be timed and adjusted to the same travel speed.

The receivers are far cheaper on Aliexpress, but you do have to wait longer for them to arrive, unless part of their express shipping service. They also sell the lasers with wire tails, rather than on a pcb. These are easier to mount into a block of wood. I used the modules as it was easer for people without soldering skills.

canaq said:

Today I finally had some time to work on my project, so here are two pictures of my creation. It's not finished yet, the laser and receiver will go inside the grey boxes, but are now temporarily mounted on top with some blu tack. I also used an old cutting board and some pieces of wood from an old stacking game.

The whole project is standalone, I have mounted a battery unit on the bottom. Cable management on the bottom is also on the to-do list

Thanks everybody for the help!

Click to expand...

canaq said:

Today I finally had some time to work on my project, so here are two pictures of my creation. It's not finished yet, the laser and receiver will go inside the grey boxes, but are now temporarily mounted on top with some blu tack. I also used an old cutting board and some pieces of wood from an old stacking game.

The whole project is standalone, I have mounted a battery unit on the bottom. Cable management on the bottom is also on the to-do list

Thanks everybody for the help!

Click to expand...

Hi,
Thanks for posting the photos. It is good to see the different variations people come up with. I'm waiting for a mecanno one )
You could try drilling 0.8mm holes in the box for the receiver and mount the sensors on little stand-offs inside the box.

There is some debate as to whether a smaller hole is required, to limit beam width. The hole can always be enlarged if needed.

Neofito said:

ok, found it https://www.ebay.de/itm/29512722682...krWYMWCTWG&var=&widget_ver=artemis&media=COPY

anyway I am gonna buy one phototransistor to build the sensor for the smartphone app, I am curious to compare results and also which one is easier to use on daily base.

Click to expand...

Jchick said:

It was written for the new laser module. I think it is my cameras. I was able to lubricate both cameras and it fixed the shutter speed issue on one of them. So it looks like i need to do a full CLA on one of them.

Click to expand...

Sorry it has proved a camera issue, I was starting to doubt the shutter tester design )

I did test it on my Canon T70, which was the first camera billed as having a 100% accurate shutter and tests in magazines at the time proved it did. On my tester, it showed after 30+ years, the shutter was still accurate.

I have no way to make a shutter tester - tester. Have been trying to think of a way. So testing with an oscilloscope trigger and my T70 are the only way I can think of so far.

There is some debate as to the width of the laser beam. Logically if the beam and sensor width were 36mm, it would never work. So following that logic, the smaller the beam, the more accurate. I had no accuracy problem with mine, but then I was only cla-ing Zenits which are not the most accurate shutters and vary exposure to exposure.
If mounting the sensors in a box, it would seem logical to make a smaller hole for the laser to enter. 0.8mm has been mentioned and is used in another tester design. It can always be made large if needed.

ic-racer said:

The same sensors are specified for the so called “Film Camera Tester” and 0.8mm gives accurate results.

I had posted earlier that the entire film plane module (pc board and 3d files) for that tester can be used on the hardware presented in this thread.

Building A Professional Grade Shutter Tester

Also obtained a real Cree XHP70.2 for testing:

www.photrio.com

Click to expand...

Hi ic,
have been watching your posts on the professional tester thread. Nice build. Must have taken a lot of dedication to get all the parts built.

Yep nicking the 3d printed receiver box from that thread would work. Would be nice to have a 3d printed box for my lasers as well, a 6mm tube could be incorporated inside, so the laser could just slot in.

canaq said:

Did anybody perhaps did some testing on what hole size is best? Is it the smaller the better, or is there a point where the hole is too small?

Click to expand...

Hi,
ic-racer has had good results with his professional tester build. It uses the same receivers, which are placed behind a 0.8mm hole.

I have not seen any appreciable errors with bare lasers & receivers, but if & when I have facilities to make a better housing, I would recess the receivers in a box with a smaller aperture window.
It would seem logical that the ratio of shutter slit and beam width becomes more of an issue at higher shutter 'speed' as whilst the shutter speed is the same, the slit width halves each time the shutter 'speed' is doubled.

Also, the speeds we use are not correct, they are altered for the human brain.

Shutter speeds are infact
32s, 16s, 8s, 4s, 2s, 1s, 1/2s, 1/4s, 1/8s, 1/16s, 1/32s, 1/64s, 1/128/s, 1/256s, 1/512s, 1/1024s

Don't believe me? Time a modern dslr or mirrorless at 30s. It will actually be 32s

Nikon state, in their manuals when using the intervalometer, that setting a 30s exposure every 30s will not work. Now you know why.
In the more advanced ESP32 version of the tester, it uses a guessing hat to find the shutter speed you have set & then does deviations from this, so human brain & correct speeds have to be accounted for.

snusmumriken said:

Very nice build! Have you added a further voltage regulator to cater with the falling voltage over time from the batteries? Or are you relying on the onboard VR of the Arduino?

Click to expand...

Right now I'm relying on the onboard VR. But I'm still a bit struggling on the best way to connect the battery. I have connected it to the GND and VIN port so to use the onboard VR, but I'm using 3 AA batteries, which results in 3x 1.5V = 4.5V.
From what I understand, the input power on the VIN port should be in the range of 7 to 12 volts. I could switch to a 9V battery, but that has a fairly short lifespan from what I understand?
I also could keep the 3x AA and use a converter to get a steady 5V output (and use the 5V port on the Arduino), but can I power the lasers and receivers directly from the converter (with the little breadboard)?

canaq said:

Right now I'm relying on the onboard VR. But I'm still a bit struggling on the best way to connect the battery. I have connected it to the GND and VIN port so to use the onboard VR, but I'm using 3 AA batteries, which results in 3x 1.5V = 4.5V.
From what I understand, the input power on the VIN port should be in the range of 7 to 12 volts. I could switch to a 9V battery, but that has a fairly short lifespan from what I understand?
I also could keep the 3x AA and use a converter to get a steady 5V output (and use the 5V port on the Arduino), but can I power the lasers and receivers directly from the converter (with the little breadboard)?

Click to expand...

You can attach your battery straight to the board's 3V3 or 5V and GND pins, but see the warnings on this Arduino page.

In stand-alone Arduino-based gadgets, I've used 4 Lithium AA cells to provide a nominal 6V, fed to the board's 5V pin via a Pololu 5V step-down voltage regulator. With lithium cells it's not necessary to use a step-down/step-up regulator, since the voltage from 4 cells will always be greater than 5V until the cells are in terminal decline.

However, the current drawn by this shutter tester in use will be very small, so batteries should last a very long time. That being, so, a PP9 9V battery connected via the VIN pin (and thus using the board's own VR) is probably your best bet. Bear in mind that domestic smoke detectors run on them for months or years!

canaq said:

Right now I'm relying on the onboard VR. But I'm still a bit struggling on the best way to connect the battery. I have connected it to the GND and VIN port so to use the onboard VR, but I'm using 3 AA batteries, which results in 3x 1.5V = 4.5V.
From what I understand, the input power on the VIN port should be in the range of 7 to 12 volts. I could switch to a 9V battery, but that has a fairly short lifespan from what I understand?
I also could keep the 3x AA and use a converter to get a steady 5V output (and use the 5V port on the Arduino), but can I power the lasers and receivers directly from the converter (with the little breadboard)?

Click to expand...

Hi,
Be careful.!!!


Applying power to the Vin pin will use the internal regulator, so a minimum voltage of 7V is recommended.
This is the safest option. It will however not be efficient as energy will be wasted in the converter.

Do NOT apply power to the 3.3V pin.

Using the 5V pin, input must NOT exceed 5.5V. So only use 3 X AA batteries.
Use of the 5V pin is not recommended. This is because if a higher voltage is applied elsewhere, for example, connecting a USB cable for FW update or to see full screen printout, a reverse voltage could flow and damage the on-board regulator.
You could, at your own risk (bla bla) use 4 X AA batteries giving 6V but also put an in-line diode. 1N4001 or similar and connect this to the 5V pin
This would drop the voltage by 0.8v, so now giving 5.2V and protect the regulator when powered from USB.

Personally, I would power it via USB lead & plug-in USB power supply most people have a draw full of them.

Please keep us updated.

A google will provide plenty of advise (not always good) and examples