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multiweb
16-11-2011, 05:43 PM
I'm interested in taking lightning/storms picies. Lately with the weather it just seems to be a logical progression into the hobby. :whistle:

With some help from Alex C. I now have all I need to run my Nex-5 with a Canon Remote. It triggers an IR remote that fires the Camera.

I'm enquiring on how lightning triggers work. I googled them a bit and it looks like most fit on the flash shoe of the camera. I'm thinking there must be a way for a standalone system to trigger a voltage and fire the IR remote in the same way.

Has anyone any info/links specifically on how the lightning triggers work?
TIA. :thumbsup:

Poita
16-11-2011, 06:31 PM
They are pretty basic, I have designed a few over the years.
The last one I made was yonks ago, so there are probably better ways to do it now, but I used to use a darlington phototransistor to turn the lightning flash into an electrical pulse, amplify it with an LM324 quad op-amp and filtering it to only respond to fast changes in light, and to only trigger on large pulses. Then just some basic components to trigger the electronic shutter release on your camera.
Probably about $10 in parts.

adman
16-11-2011, 06:34 PM
they obviously work - but I would have thought that by the time the flash had happened, and then triggered the camera it would be too late.

I guess the only other way is to close the aperture and reduce the film and shutter speeds to the point where you can take sequences of images of a few seconds duration each and hope to catch something by sheer luck.

Bassnut
16-11-2011, 06:39 PM
Leave the shutter open (on B) with low iso/aperture and let go as soon as you see a flash?

Poita
16-11-2011, 06:43 PM
From memory the July issue of Silicon Chip magazine had a lightning detector circuit published, you could just add a simple trigger to it to fire off the camera.
I tend toi know a lot of people just keep the shutter open during storms until the lightning hits.

gregbradley
16-11-2011, 06:44 PM
I've taken lightning shots before. I did what was mentioned here- turn the ISO down as low as possible and hold the shutter open for as long as possible.

It works best at night. Also lightning often has a repeating interval - a bright lightning bolt every 30 seconds so you can wait until you think one is imminent and then open.

I usually kept the shutter open for about 30 seconds hoping to catch something. I got some good results.

It'd be a lot harder in daylight. Although I did a great one once with an approaching storm and frequent large bolts. In Sydney at least, storms are usually late afternoon or early evening and an approaching heavy storm makes conditions a bit dark anyway.

I wouldn't suggest sitting on a metal roof in the rain to take one like I did but I did get the great shot!

Greg.

sheeny
16-11-2011, 07:02 PM
I usually just take a series of 30s shots and toss out the ones that don;t have lightning in them.:) To help do this during twilight I have a few ND filters I put on the lens (also useful for smooth water shots;)) but I don;t have enough to get 30s in full daylight.

As for the lightning triggers, the theory is that the lightning strike is actually 4 to 6 short strikes over the same track spread out over many milliseconds. The first strike is detected by the trigger, and the shutter is opened before the last strike.

Al.

Poita
16-11-2011, 07:10 PM
The last lightning trigger I made was for catching shots of lightning during the day.

I'd say now you would just use an arduino or similar to do it, along with a simple sensor. They are cheap enough now, especially the clones.

Moon
16-11-2011, 08:17 PM
My meteor camera (http://deepspaceplace.com/meteor.php) picks them up all the time. It's a video camera with time shifting using UFOCapture. The quality is terrible though - it usually just washes out the entire image. Usually has rain on the lens and lots of clouds too.
James

multiweb
16-11-2011, 10:29 PM
Thanks for the info and all the ideas guys. I found some info here (http://www.aeophoto.com/Select_LSII3.html)and emailed them for further details. The trigger output is a 2.5mm audio jack similar to the TC-80N3. the various camera specific cables also look very familiar so I'm confident that the voltage output will be close to what a standard intervalometer would provide. I know what to look for and can work out the wiring. The only unknown at this stage is timing. I don't know how much lag there is between the IR firing and the NEX-5 shutter release. I guess triggering within the ball park is better than nothing but I would assume it is as fast as a direct cable connection?

Exfso
16-11-2011, 11:08 PM
You might want to contact Astroman on this forum, he built his own trigger and apparently it works a treat.

Poita
17-11-2011, 02:46 AM
If you are going to spend that sort of money, then get something more versatile like this:
http://www.cameraaxe.com/wiki/index.php?title=Main_Page
http://www.dreamingrobots.com/store/index.php?main_page=index&cPath=1

or this:
http://www.doc-diy.net/photo/smatrig21/#lightning_trigger

multiweb
17-11-2011, 08:09 AM
Thanks all. :thumbsup:

PS: as some people asked me for more info about the remotes here's a pic of the set-up. The wiring details are available on Alex C. blog (http://www.terrastro.com/blog/sony-nex-5-timer/). You can also get an AC adaptor from SONY or eBay to run the NEX-5 off the main and a 32GB card should give you 16h worth of imaging. Bit over 6000 subs. So plug n' forget type of thing.

Astroman
17-11-2011, 09:22 PM
I built my own trigger using a circuit from http://www.solorb.com/elect/lightning/ Works good during the day, but I tend to use the "old fashioned" method for night time stuff. The critical part is the shutter lag. On my Canon 400D the shutter lag can be quite long, I think it was something like 100ms or so. This is very hit and miss with lightning. If the Lightning pulsed then I could almost guarantee I would get it. But many types of lightning have various effects. If you are running an IR system to release the trigger it may be similar to my 400D or slightly longer, only experimentation will prove if it will work or not. During the day I also use an ND filter so I can slow the shutter speed down a bit, just in case there are secondary bolts.

The triggers you see attached to the hotshoe are only there because of convenience, it's just handy to have it sitting there pointing in the same place as our lens. My trigger uses a 9v battery which powers the unit for months. Handy since I have large switches and sometimes they get bumped on.

I think by what I have just read the NEX-5 only has IR remote, so unless you hack into the camera you can only use the IR to control the trigger. So looking at the image above if you use the trigger in place of the intervalometer then you should be able to trigger the cameras shutter.

The circuit above is very adaptable and can even be made on breadboard, I made my own PCB but I cannot find the drawings for ir now... Here are some pics of it, which may help..

This was the first one I made, I modified the box to make it fit better.
http://i363.photobucket.com/albums/oo73/AstromanSID/triggerlogo/lrtpcblayout.jpg

Here is the finished unit on the camera.
http://i363.photobucket.com/albums/oo73/AstromanSID/Weather/Lightning%20Trigger/trigger001.jpg

and here is a strike taken by the camera/trigger
http://i363.photobucket.com/albums/oo73/AstromanSID/Weather/storms251109-013_untouched.jpg

and...
http://i363.photobucket.com/albums/oo73/AstromanSID/Weather/lls05.jpg

All taken with the 400D and the trigger.

If you want to shoot lightning at night then there are other methods you could try, if you want help with that let me know so I can look up the manual of the NEX-5 to work out a plan.

luigi
18-11-2011, 04:16 AM
I do the same, I program the intervalometer to take 20-30 second shots on continuous mode and then examine what I got in them.

multiweb
18-11-2011, 08:53 AM
Wow! Thanks for that. :thumbsup: Very involved for my electroninc knowledge though.



Yes - I will try that as well.

ZeroID
18-11-2011, 11:21 AM
Make sure you have turned off the Autofocus. Mine is almost instantaneous but it's a semi pro camera.

There are plenty of remote shutter/flash control toys out on the interweb. Lightning normally lasts about half a second or more for serious flashes, the current maintains the strike. If using a light detection trigger set the shutter for about 1 second to get it all.
Otherwise the open shutter, hope and wish system is the next option.

Phil Hart
18-11-2011, 12:07 PM
Not so much for Marc, but the reason for having a trigger and not simply doing continuous bulb exposures is that it allows you to shoot lightning in quite bright conditions.

you can only do the bulb approach at night, but with the lightning trigger, you can set say a 1/4 sec exposure, f8, ISO100 and catch lightning during the day (if conditions aren't too bright). trying to do 1/4 sec exposures continously without the trigger soon fills up your memory card!

i've been using one in a few storms here and getting a bit more used to it. this is not the unit i have but has good info:
http://www.lightningtrigger.com/Tips.html#photographytips

Phil

multiweb
18-11-2011, 12:32 PM
Yes - I always focus manually.


I ordered one with a Canon/Pentax 2.5mm cable that will be compatible with my IR remote from here (http://www.aeophoto.com/Spec_LSII3.html).

Poita
18-11-2011, 03:06 PM
That is why decent lightning triggers can also set the 'half press' of the shutter button, so that it sits in that state until the lightning appears. It speeds up the shutter firing considerable in cameras that don't have full manual functions.

Paul Haese
18-11-2011, 04:05 PM
Hi Marc,

just go buy one, they are cheap on Ebay and work 100% of the time. I have had mine for a couple of years and plan to use it again today.

This was (http://paulhaese.net/Rainandlightning.html)taken at night via traditional method but it is at night.

Same as (http://paulhaese.net/lightningoverAdelaide.html)this one.

However, for day time you need the trigger (http://www.lightningtrigger.com/). Day time you cannot capture lightning reliably. It would be a one in a million shot to capture it.

This image (http://paulhaese.net/Crawling.html)was triggered by it. This one (http://paulhaese.net/Geraniumstorm16feb2011.html)was also triggered by it but it was sheet lightning(not definable in the image). The sheet lightning was thick on that day the trigger kept releasing.

Have fun and stay safe.

multiweb
19-11-2011, 05:21 PM
Mine's in the mail now. Looking forward to playing with it.

BlackWidow
19-11-2011, 09:24 PM
I had a look on Ebay and foung a guy in Germany selling triggers for $69. Seems to have good reviews so I have ordered one. I put in an offer and got a better price, i could not make one for that price. I will let you all know how it works when it arrives. Works in the day as well as night so this will allow me to do more. I thought of making one, but not worth the time to me to save $ 20 or $30 off the cost of parts


Regards
Mardy

Davros
20-11-2011, 07:29 AM
Can you put a link up to the one you went with.

multiweb
02-12-2011, 08:24 AM
Some relevant info with a cool article (http://www.redbubble.com/people/grayam/journal/6547100-chasing-the-perfect-lightning-photograph).

multiweb
13-12-2011, 05:56 PM
Just received my trigger from AEO photos along with a Pentax/Canon compatible cable. I chose this type of cable because it comes with the standard 2.5mm stereo jack. Plugged it in the IR remote I hacked to work with the intervalometer and bingo, worked out of the box. I had to disable autofocus and various other things in the NEX-5 settings to minimize the response time with shutter opening and it feels fast enough when blocking the sensor with my hand but the real test will be when I get out in a real storm.

Astroman
13-12-2011, 08:07 PM
Awesome news, can't wait to see your results..

niko
13-12-2011, 08:56 PM
And whaddya know...mine arrived today!

Astroman
13-12-2011, 09:04 PM
Shame it wasnt a few days ago when there were storms in Vic :D

Now you wont get any...

niko
14-12-2011, 11:59 AM
Andrew,

you're so right! About a week ago I rode home from the city amid a gathering lightning storm thinking if I can just get home and set the camera up even without the trigger (which hadn't arrived) I should get something. The storm was getting so bad my wife even picked me up in the car - droive home with massive lightning all around us.

Raced into the house grabbed the camera gear. Even as I screwed it onto the tripod the frequency diminished. The last strike occurred just as I took the lens cap off!

Anyway - maybe some summer storms down at the coast over Christmas.

The rigger was slightly damaged when it arrived. The On/Off switch had come loose from the rather light amount of glue holding it in place. It was only in a lightly padded bag for postage so I think it happened in transit. I've let them know

cheers

niko

multiweb
14-12-2011, 12:51 PM
The good thing about it is that you just frame your shot, leave the camera overnight under a awning then check in the morning if anything happened. It's like fishing. :fishing: