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View Full Version : Water Strobe/Flash stuff...I don't know..



purephotos
29-01-2009, 9:37pm
I tried some photography the other day of dripping water drops into calm water as well as "firing" it out of a syringe. I took over 100 photos and trashed the whole lot. I dumped because they are all out of focus. The only reason I can see for them to be out of focus is that I'm using macro. The lens I'm using is a Nikkor 35-70mm f2.8 that has built in macro. My problems are: How do I get good depth of field; and: What can I use to trip the camera because they way I'm doing it will take 1000's of shots to get what I want.

Thanks in advance.

-R

ricktas
30-01-2009, 6:31am
You need to use manual focus. Pre focus on the spot you want to, Also increasing the ISO helps so you get as fast a shutter speed as possible. Try and get to 90 degrees to the water path so that the water crosses in front of the lens at the same distance. If it moves closer or further away, it will be out of focus at f2.8 due to the very shallow Depth of field.

Try decreasing the aperture to F4 or so, but the smaller you go the more it decreases the light hitting the sensor, and therefore you need slower shutter speeds. So ISO is the key, but don't up ISO to the point you get to much noise.

Bunyip
30-01-2009, 7:25am
I think you might get good results with your flash, especially if you trigger it with an extension cable (links the camera to the flash when it is not in the hot shoe) and position it to the side of your subject. You'll want to set the D200 to 1/250 second shutter speed, which is the maximum for flash sync. The extension cables can be found for about AUD $30.

As for timing your shot, that'll be trial and error, but you'll get a good one eventually.

dantheman
01-02-2009, 9:14pm
I was reading a thread about this recently, i thought it was on here but maybe not. They were trying to get similar pictures, however insted of taking a picture and hoping you get the shot due to timing they set up slightly different. I dont know if it works cause i havent tried it.
It has to be done in a very dark room though.

The camera was set in its spot and manualy focused, then set with a slow shutter speed of around 1 or 2 seconds. Then you use your flash seperate from the camera and press the button that tests the flash. you still have to get the timing right, but it sounds easier as the focus isnt affected.

Like i said i dont know if it works, but the theory sounds reasonable. The flash only lasts a very small fraction of a second so if there is no other light or limited light to enter the lens i guess it would work, lol

anyway if you get bored and do try it let us know if it works. Sorry if it doesnt, haha.

Dan

purephotos
03-02-2009, 6:55pm
DAn: I tried that already, but it didn't work. I'm thinking about making an optical/audio trigger for the flash with a time delay circuit.

-R

dantheman
04-02-2009, 8:44pm
thats a good idea, but how sensitive do you think it would be, there isnt much noise involved with water drops, unless its late at night and your trying to sleep.

purephotos
05-02-2009, 4:51pm
hahaha. I'm sure I will find a way. I can build an amplifier and make the mic very sensitive.

-R

sixfootfour
05-02-2009, 5:30pm
Increasing your ISO and keeping the shutter speed at 1/250th will allow you to use a smaller aperture for greater depth of field while maintaining the correct exposure.

Bax
05-02-2009, 6:54pm
Back when I looked at this last I believe it was triggered with an optical/ IR beam sensor, and the time from the beam to the water level was set in a timer delay.

This is one of the unit's I've seen, I guess you'd need an external sensor to coincide with it.
http://www.bmumford.com/photo/camctlr.html

And here's another link, I'm still not convinced microphone is the way to go.

purephotos
09-02-2009, 8:57pm
hmm. The microphone is more for another set of shots I was thinking of doing which involves paintballs and hard surfaces. Nuff said?

-R

Bax
09-02-2009, 10:37pm
Certainly does, as long as you share when you're done. I'm interested.