AF Assist project: laser pointer triggered by hotshoe

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None of the Canon cameras turn on the AF assist light (the red light) on external flashes continuously after focus has been achieved.

I’d like to stick a laser pointer (one that projects a pattern) in the flash slot and paint the subject with some sort of laser light pattern to give the AF sensor something to easily focus on. This way, if the laser light is on continuously, then I can use the AI Servo mode to continuously track the subject in low light situations.

In order to turn on/off the laser pointer, I will use the top left most small pin off the flash hot shoe (not the big round one). See diagram in this thread.

Canon hotshoe pinout description here.

I may have to tweak the diagram shown in the link to turn on the laser pointer, but it should be doable.

The beauty of using the signal off the hot shoe connector is that it comes on only when the camera needs to focus, and stays on only for 7 seconds after it’s done focusing, or 3 sec after the shutter is fired.

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Update: 20 Sept 2010

I went to Club neutral last night and shot some pictures there. (Description of results from that night’s shooting at this post) I took the laser pointer with me, but I could not reliably use it. I had no mount for it other then the velcro I brought with me, which couldn’t keep it in one place especially when having to push the button all the time to trigger it.

When leaving the club noticed a red led bike light, and thought it may work for me too. Tried the red led bike light I have, to see how well it would assist the camera in focusing. Compared to the AF assist light from the Sigma EF500 DG super flash, it took almost twice as long to focus, and at times the bike light didn’t even acquire focus. So much for a simple solution.

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UPDATE: 24 Sept 2010

Came across a few forum posts where people are discussing AF assist lights. This chinese site has an interesting idea.

Also this forum and this forum have discussions on AF Assist lights.

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UPDATE: 02 May 2011

I have progressed this project further.  Check out this post for a working laser AF assist tool.

Camera bags: an epic email

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An email message from my friend Ben, regarding camera bags. Keeping some excerpts  for reference.

… My working configuration when i have multiple lenses is to have at least one empty slot in the bag so that i have somewhere to put the lens down so I only need one hand to manage lens swapping (reduce risk of dropping lens too!). If i need to cram more lenses in my bag, which i do when I have backup lenses with me, is to put the least used lenses at the bottom of a stacked compartment. The lens is there if I need it

Good to know. I will have to make an effort to keep an empty slot in the bag to facilitate the easy changing of lenses.

The UD 40 is the largest bag that I’d carry while trying to stay low-profile. I use mine in two different ways depending on what I’m doing.

1. Gear hauling:
I’d probably pick another bag for gear hauling tonnes of gear but I’ve used the UD40 before as a way to pack a lot of equipment into a small volume. In this instance I wouldn’t be able to access the equipment very quickly but I can get a lot of gear from A to B in one bag. Lenses would be removed the bodies and the bodies would go into the two front slots. Lenses and flashes would go into main compartment that’s separated with dividers. I either have the main compartment divided into only 2 or three sections.

2. Shooting bag:
Here, I’d be carrying 2 bodies (no battery grip) with lenses(usually 35/1.4 and 85/1.2) attached. Each body/lens combo would go into one of two main compartment sections. For me, this is the best way that I’ve found for “casual” shooting. I don’t usually carry lights with me for unpaid gigs. It just too much for me to carry. My preference is to carry 2 bodies with lenses rather than 1 body plus a flashes+transceivers+stands

And below is what I do for weddings:

My base kit ( 3 bodies, 5 lenses, 3 strobes, transceivers, 2 light stands)
goes into an Airport International roller bag:
http://www.thinktankphoto.com/products/airport-international-v2-roller-camera-bag.aspx
I also have another big bag for 2 AC-powered strobes and a 48″ lightstand bag.

When I’m actively shooting. I’ll be using a chest pack + 2 skin pouches attached onto the “wings”: The pouches were made to carry bodies only, but i use them to carry lenses instead (each pouch can hold up to two lenses, but i leave an empty spot in each of them to facilitate lens switching…)….I’ve also recently found out that you can fit a body and a prime lens attached into the pouch….very handy when you’re shooting three bodies at once. Yes, I’ve run out of hands! 🙂
beltpack: http://www.thinktankphoto.com/products/change-up-belt-pack.aspx
(I totally look like a photo dork with this on, but this feels more
comfortable to me than just using a belt with pouches)
pouch times 2: http://www.thinktankphoto.com/products/skin-chimp-cage.aspx

My active set up doesn’t let me carry strobes, but If i need to I can wear a backpack to let me carry more stuff. So now i look like an even bigger photo dork:-)

Digital camera; not a toy anymore

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I just read a facebook post the Ben Wong put up. It read “I don’t just buy cameras, I use them too” (I think he was referring to using a recently purchased medium format film camera).

This post got me thinking.

To a certain extent, I think I have passed the “cool new toy, with cool features” with reference to a digital SLR camera, and am now more looking at what gear (film or digital) will create the look that I’m looking for. I’m now more interested in learning how to achieve a certain look, rather then ‘play’ with a new toy. Sure I’ll be excited to get a new body, but it will now be a means to an end (or rather a look) that I’m after more then just the next toy to ‘play’ with.

I’m happy with myself.

🙂

Club photography: Lighting experiment

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I was thinking about experimenting with a couple of flashes next time I go out club shooting. I do a lot of shooting at Club Neutral here in Toronto, and I thought I ‘d start my experiments there, since I know the layout of the place.

Above the dance floor, there is a frame that is attached to the ceiling which holds all the lights. I can easily reach this frame (ceiling is low at Neutral) I am going to attach 2 flash units to the frame. One at the front pointing away from the stage (towards the DJ booth at the back), and one at 90deg to the first strobe. And point them to illuminate the crowds.

Both flashes will always go off together, and what I’m hoping to accomplish is to always have light available when photographing crowd members dancing. Having 2 light sources at 90deg to each other should (emphasis on should) ensure that my subjects will always at least have side lighting.

Now this will light up the entire club, so all the people will be lit up. To try to isolate just one person dancing, I will shoot from down low. This should ensure that I only capture the person dancing with minimal heads in the background.

I’ve made some clamps (and will also buy a proper one) to clamp the flash to the existing structure at the club.

Will add to this once this experiment is complete.

Improv 201 class 8

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Skipped to class 8. Class 6 was a hybrid class with a 101 class since we and they had very few people, we joined the classes together.

Class 7 I did not attend.

Class 8.

I realized on thing during this class. I think the reason I enjoy improv is because it is an outlet for me to express extremes of emotion. I’m pretty laid back, which means only subtle variations of emotions get expressed. Improv not only allows but to a point encourages the display/use of extreme levels of emotion.

Learned the Harold pattern. Group, 1A, 2A, 3A, Group, 1B, 2B, 3B Group, 1C, 2C, 3C. And got a chance to put on 20-ish min ‘shows’ to get a feel how quick time passes. It didn’t seem like a big deal to do a Harold: time flew by.

Lessons learned in photography

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In dim lighting conditions, always use some form of AF assist. Be it a flash red AF assist light, our the camera’s flash AF assist, use it.

On the 40D, the focus confirmation will tell you the shot is in focus, however when examined afterwards on a computer, the short could have been sharper. This is especially true when shooting at wide apartures of under f2.0

I have ordered a laser pointer that continuously projects a pattern, and will strap it to the camera body to paint the subject with something that the AF sensor can track and focus reliably in low light, when the flash is not available.

Improv 201 class 5

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Commit to your point of view. It not only helps you, but it helps the others.
Saying no in a scene; you can say no in a scene, as long as you commit to it.
Yes and… make sure you ‘yes and…’ the same character, even if he’s the guy that says no.

Before you tag someone out,  make sure you understand the existing interaction (the game), not just one character’s POV.
When tagging in, make the interaction obvious; put words in the other’s mouth with you first statement; it helps define the scene for both of you.
LISTEN LISTEN LISTEN. Listen to what you are saying and how it affects and adds to the scene, and really listen to what the other person is saying.
It’s not about adding more stuff to a scene. It’s about the interaction. That’s what needs heightening, not the where or what. It’s the who, and their relationship.

Improv 201 class 4

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Make connections: how do the things connect?

Why is the other person saying what they are saying? What do they want from the interaction? Work with the answers to those questions to build on for the scene.

Don’t try to solve the problem (when a problem is presented). It’s more interesting to escalate the interaction then provide solutions.