Category Archives: Photography

Camera Aid idea

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In concert photography, where light is at a minimum, the capturing of images is tough. But sometimes, bright lights flood the stage in often seemingly random intervals and for brief periods of time. I’m not talking strobes, but spot lights that come on and then go off again in matter of 1 second. Enough time for me (the photog) to realize there’s lots of light, but by the time I push the shutter, the light is gone.

Yes I realize that training the photographer is simpler and cheaper, but I’m a geek that like to build shit.

Build some sort of device that triggers the camera to take a photo which when turned on will focus and snap a photo based on light levels passing a certain threshold. The light sensitive are should be directional. I don’t want it going off just because buddy’s flash went off 3 feet from me.

AF Assist tool v3.0

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To layout the expectations for the next AF assist tool. The last AF assist tool v2.0 had it’s weaknesses, and I will try to address some/all of those with the next tool.

Some of the changes from v2.0 to v3.0:
– Explore the use of other AF lights. Try lights with grids from existing flashes, near IR leds, (others) to achieve a pattern/light that is both not distracting to anyone and not very visible yet enables a DSLR to quickly focus.
– Follow and recreate some of the efforts out there to reverse engineer the ETTL protocol and use it to keep the tool on ONLY while the camera is focusing. The two sources for the reversed-engineered protocol are on Kzar.net and Bill Grundmann’s Blog. I’ve wanted a project for an Arduino, and this may be the one.

 

Some more efforts to create an AF assist light:

http://www.flickr.com/groups/strobist/discuss/72157625363074208/
asa

http://www.youtube.com/watch?v=IhiHNzx0tMA&feature=related

AF Assist tool v2.0 log

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I recently attended a 5 day music festival (Kinetik Festival) in montreal, Canada where I was asked to photograph the 35 bands playing. A month before the festival I had a chance to try out my first AF Assist tool. After seeing the results I knew I wanted to take such a helpful tool with me to the music festival to help in the making of images. This is the second incarnation of my AF Assist tool.  Continue reading →

Kinetik preparations

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Preparations for the music festival: a list of what I should pack, and take with me.

Photo gear equipment:
– Camera (+backup)
– charge all batteries (AA and camera batteries)
– clean all lenses
– tripod :make sure all parts are there.
–

Clothing:
– rain coat
– hiking boots
– assortment of clothing
–

Computer:
– get 250gig drive cleaned out, got a new 500gig and formated.
– take cable to tether phone to laptop (USB to microUSB)
– install Bibble on computer
–

Others:
– earplugs
– advil
– pepto-bismol pills
– Cliff bars
– energy drink (buy in MTL)
– Allergy medication
– nail clippers
– bathroom supplies (soap, shampoo, q-tips, toothbrush, tooth paste)
–

Daypack:
– laptop + charger+cables + USB drive (to format)
– water bottle
– snacks (fruit, crackers)
–

 

Things to keep in mind while shooting:
– remember the 1/focal length rule. So for the 85mm lens, shoot at 1/125, the 135mm lens shoot at 1/150 -1/200. Up the ISO to get the shutter speed required. Better to have a sharp noisier image, then a blurred cleaner image.
– camera AF on AI Servo, Spot metering, use only the center AF point.

AF Assist V2 (Update 17 May 2011)

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Continuation from this post. Build and experimentation log continues.

I built the unit and tested it last week. The laser seemed lower power then the first one I built (which was just the laser pointer hooked up to a set of 3 AAA batteries along with a pushbutton).

Last night I had time to take a multimeter to it. The laser LED is seeing a total of 3.4V from the output of the LM358 OpAmp. The rail voltage was 4.6V (3 AAA bateries) yet the maximum I could coax the output to put out was 3.3V – 3.4V. This explains why the laser beam seemed weaker at first try.

I’m really going blind here using an OpAmp. Did lots of googling, but found nothing to explain this behavior. I tried several LM358, and they all worked the same way. It must be how they work.

So after an hour of dead end attempts and research, I decided to add a 4th AAA battery (for a total of 4 AAA) to give the op-amp 6V, and that did the trick. Now the laser LED sees 4.3-4.4V, and the brightness is back to what I remembered. Continue reading →

AF Assist tool – Version 1.0

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Last september (2010) I wrote a blog entry about hooking up a laser pointer as an Auto Focus assist light for a camera. The need came up because I wanted AF assist in AI Servo focusing mode of my DSLR. Currently to my knowledge all Nikon and Canon DSLRs will only put out the flash AF assist beam until focus is achieved. After that if the (if the camera is in AI-Servo focus mode) if the subject moves and the focus changes, you’re out of luck in dark situations because the AF assist beam will not continually come on to keep assisting the focus.

The previous look at using a laser pointer as an AF assist tool,  I had very little success with that projects. Last week I came across the laser pointer again and new thoughts/ideas came to mind.

So I rigged a laser pointer to a bunch of batteries and a push button to act as an Auto Focus assist to my Canon 40D. The results are spectacular.

I’ve already started working/thinking about the next version of this. Updates on the AS Assist Tool V2.x will be here.

This is what I did, and how it worked.

Continue reading →

Kinetik photo preparations

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Want to sort out what I will be needing for the Kinetik festival this year in terms of camera gear.

The lineup calls for 7 bands per night (sometimes 6). 5 days worth of music.

Q – How much memory should I take with me.

A – Well, at the Combichrist show, I ended up with 21 gigs of photos for the 3 bands that played that night. That’s been a record for me for # of photos taken at a concert. So assuming 7 gigs per band (on average) and assuming 7 bands per night, I’ll need 49 gigs of memory. 3 cards of 16 gigs will give me 48 gigs of space, plus the 8 gig and the 4 gig cards I have, that means 60 gigs. More then enough.
I will buy 2 more 16 gig cards. I will buy a 32gig card instead of 2 x 16 gig cards from here.

UPDATE: Borrowing a couple of 32 gig memory cards from Ben.

Q – How much battery power will I need for the flash?

A – At a Neurodance event, where I use a lot of flash I will probably go through 2 sets of batteries in a 5 hour span, and I use the flash for nearly every shot (probably 300+ shots taken). The canon 580 manual states 100-700 shots can be taken on a set of 4 new AA batteries.
So assuming 200 shots per charge,  I’d say 3 sets should be sufficient. I will bring 4 sets (since I have them)
What I should also look at doing is making a portable battery pack (that will take say 4 packs of batteries) which would eliminate the need to change batteries throughout the night.

A- Seems the camera batteries are not holding much of a charge. Get a set of camera batteries too,

Q – What lenses to take.

A – That’s a tough question… maybe look at renting a lens (EF 135f2) for a week (it’s $75 for the week for the 135f2).
I don’t think I want to carry the large camera bag with me, and the smallest one may be too small. Will have to investigate.