The inventor states sound is OK for under 1/30th and above that light is better. I agree.
Originally Posted by Jim Graves
The inventor states sound is OK for under 1/30th and above that light is better. I agree.
Tin Can
Nice to hear that the plug works for you
Here is a new batch of plugs, 6 are left: http://www.ebay.com/itm/Shutter-Spee...item3a826e421f
Hi Lukas,Hi,
my name is Lukas and I wrote a little app for the iPhone that allows you to check the shutter speeds of your cameras or your LF-lenses.
I thought this might be helpful for one or two, so I'm telling you about this
The App itself uses a acoustic measuring method to determine the shutter speed: You can record the shutter release sound, and the App displays the waveform of this sound. Because the shutter makes a noise, when it opens and closes you can see two peaks in the signal. The time between those peaks is the shutter speed of your lens/your camera.
Attachment 97141
Of course, this acoustic way of measurement has it's limits. That's why I invented a small extension for this app: A phototransistor-plug. With a small phototransistor at the top, it allows you to measure the actual light passing through the lens:
Attachment 97147
It's pretty simple to use, just point the camera or the lens against a bright lamp, position the fototransistor-plug behind it, and release the shutter:
Attachment 97143
What you get is a waveform like this:
Attachment 97145
You will see two clear peaks, and you can easily determine the shutter speed from this.
The App plus the phototransistor-plug is a very powerful tool that allows you to check the accuracy of your lenses/your cameras quickly and without wasting money for film. I already sold several of them and I only get positive reviews about the plug.
If you are interested and if you have an iPhone/iPod Touch/iPad, I would be glad if you give it a try:https://itunes.apple.com/us/app/shut...l=de&ls=1&mt=8
And if you like the idea and want to get more precise measurements, especially at faster speeds, you may want to try the phototransistor-plug as an extension: http://www.ebay.com/itm/Shutter-Spee...item3a81f265cd
Thank you
Best,
Lukas
I have downloaded the app and i will begin to test it shortly but great app and nice sharing keep up the great work
I tried it out briefly this evening with the phototransistor-plug. So far so good!
“You often feel tired, not because you've done too much, but because you've done too little of what sparks a light in you.”
― Alexander Den Heijer, Nothing You Don't Already Know
I also tried the app and it is very convenient to use for a quick audio test. I like how the app can be opened in the field to show pre-tested charts for my lenses. It would be good if the recording time was configurable to be more than three seconds. It is sometimes hard to get the iPhone in the right position before the shutter release starts.
I agree, juggling the whole mess in the field could be difficult.
My first uses were fully handheld, and nearly impossible, but if I set-up on a flat surface with a flashlight it becomes possible for me to barely do it in 3 seconds.
5 seconds would be better.
Are those metric seconds?
Tin Can
Ok, I will try if it is possible to extend the recording time to 5sec.
Indeed it is a little bit tricky to hold the camera and the iPhone together in both hands, pressing the record button and releasing the shutter at the same time.
Let me show you how I do it:
Here with a leaf shutter camera:
I hold the camera in my left hand, so that I can release the shutter with my forefinger. In my right hand I hold the iPhone, so I can press on the record button with my thumb.
Analog with a SLR:
Camera in the left hand, with my middle finger on the release. iPhone in my right hand, analog to the leaf shutter camera.
I hope this tips help a little bit
I have real arthritic hands as many of us old people do, what is simple for you is a miracle for me. I am worried I'll drop something, hence the table and flashlight method.
I do like the APP and the lightmeter dongle, it is sensitive enough to 'see' fluorescent flickering from AC current.
Keep plugging it all over, if it was a Kickstarter you may have raised more money for development.
Tin Can
For large format lenses, the easiest thing to do is to mount them in a camera. Stop down the aperture to a working stop, say F22. Remove the camera back and compress the bellows a bit Move a light to in front of the lens. Don't get it too close to the lens if the light produces a lot of heat. I use an Jansco LED. Attach cable release. Set time and then cock shutter. I fire the shutter a few times before taking a reading. It should now be fairly easy to hold the ipod behind the lens while tripping the shutter.
“You often feel tired, not because you've done too much, but because you've done too little of what sparks a light in you.”
― Alexander Den Heijer, Nothing You Don't Already Know
Here is a table of a small test I did, comparing Lukas' tester in acoustic mode and with his optical sensor against a Calumet shutter tester. The shutter was a Copal 1 from a 210mm Nikkor W. The first column shows the nominal time in fractions, the second column the nominal time in milliseconds, the third column the Calumet tester result in milliseconds, the fourth column the iphone tester results with the optical sensor converted to milliseconds, and the fifth column the iphone tester using the microphone converted to milliseconds. The times between the three test units/setups are well in agreement for all practical purposes.
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