My name's Alastair, I'm a British ex-pat living in Germany.
Just discovered the world of Arduino and after a very long time not doing anything with electronics, decided it was a good time to start a project!
My first project is for a SLR camera trigger using audio, light and maybe other sources. I started a blog to document my progress in the hope it might be of some help or interest to other people venturing into the world of Arduino...
Any comments, help and ideas would be greatly appreciated
Apparently I need to make a post before I can post a link to the blog
...nice work here, I like that. Also because I am working on the same but I do not such a nice Blog-documentation as you do.
You might be interested in the following:
Thanks for the comment and forum welcome. Things are starting to move on now; I'm really enjoying re-discovering my electronics past!
Hans, thanks for the blog comment, sorry, I have comment moderation switched on, so I have to accept comments before they are published. Helps avoid spam comments!
Hi Alastair,
I just added a post to your project blog offering to share some of the work in this respect I have done so far.
As you say there is not much to do untill the hardware arrives....
Well, my HW has not arrived yet, so I did some work regarding exposure times only. That's all I've got to offer for now.
In your blog you mention that you'd like to obtain 'more precise control of bulb exposures, i.e. 7.3s exposure time.'.
YESSSS, me too.
Also I really like your intention to have various kinds of triggering meachnisms activating the cameras exposure.
Cool, now we can catch an image of a drop of water hitting the surface without using a highspeed-exposures camera (or a baloon exploding).
So here is my question: in my calculations I found that (for my intentions) it is necessary to use mircoseconds instead of milliseconds. I'd assume that ARDUINO is able to handle that kind of really short instructions, BUT will the camera as well, when in Bulb-mode?
Another factor is that the shutterlag needs to be taken into account.
My intention is to build something very similar to the 'Bracketmeister' (by J.Geerds, NYC Panorama), but that the span of possible exposures reach into the realm of microseconds in 1/3EV steps (this is the work I have done so far).
Also I'd like to mention that I am neither a good source as a coder :-[nor very knowledgeable in electronics :'(.
Nevertheless I hope I have woken up your interest and look forward to your response.
...this is the place where I started my Project-Documentation for the 'electronic-remote-shutter-release-timer': http://www.halo-photographs.com/long-exposure-hdr-photography/
Go to 'Resources...' at the bottom and open that Excel sheet, again observe the tabs at the bottom.
(Please keep it low key for now as there will be lots more edits.)
Regards, Hans.
Yes the timing issues is very important for the high speed photography. The Arduino shouldn't have any problem triggering in the low end of microseconds and I've been doing some testing of the output timing with different resistor values (must update the blog for this info!). At the moment I would be expecting a triggering time of around 15 to 25 microseconds from the trigger event.
Regarding shutter lag, this is really a bigger problem. One solution that might work for me is to use the live-view function of the camera where the shutter is already locked open, so in theory the lag should be reduced. The 2nd option is a change of technique - rather than triggering the camera, the scene is set in a dark room with the camera on bulb exposure. The trigger is then used to fire a flash unit at the required time to provide the exposure.
I think a lot comes down to what you want to photograph and how fast you need your exposure to be. For example if you are using a BB gun or air rifle to shoot something, then using an audio trigger from the sound of the gun, you have the time it takes for the pellet to hit the target to trigger the camera, so shooting from further away gives you a longer delay to work with! It may even be necessary to build in a delay from the trigger activation to firing the camera.
At the moment I'm not worrying too much about all that I just want to get the trigger working, then I can start playing with the parameters and trying to speed things up a bit
I hadn't really considered the idea of exposure bracketing for HDR processing. Its a really good idea
For fast shutter speeds, you are probably better letting the camera do the exposure bracketing, unless you need wider brackets than your camera supports!
If you know the shutter lag time, you should be able to compensate for this to get very accurate timing, although when you are looking at exposure times of several seconds you can probably get away with far less accurate timing!
Hi Alastair,
how is Photo-Project comming along?
Thanks for providing the drawing about the Optocoupler. Works great.
Got mine finished based on 'Bracket-Meister' and it's working great. Had to change some of the code and now it flies 90%. The 10% I am having trouble with is that I cannot get a faster exposure than 1/10th of second in a fully controlled manner. How about you, do you also reach that limit when shooting in Bulb-Mode with ARDUINO? I am curious to know, though I assume it's the camera that does not allow to take a faster shot when in Bilb-Mode.
Have a look at my Project-Docu (not so thorough as yours) but still.
Looking forward to hearing from you.
Good luck, Hans.
