Focusing (laser) beam/pattern anyone?

Nikolai

At some point certain cameras (advanced P&S, like Sony DCS Fseries) used to through what looked like a dim laser web pattern to help their AF systems. I understand the trend was kinda shut down due to 9/11 and consequent security elevation. However I do thing the idea was great, since the beam was retatively low-intensity and non-intrusive, however it helped a great deal in the scarcely lit and dim wedding venues,
I'm wondering is there is a flash-light-like tool the market that could be used next to any camera to hel with AF by emiiting similar laser pattern.
I know there are plenty of laser pointers, may somebody figured out some beam splitting device to attach to them?
What do you think/know? :ear

Richard

Nikolai wrote:

What do you think/know?

I'm not sure an external beam would help without the AF system being programmed to expect it. Are you using the flash AF-assist light? That seems to work pretty well for me.

BenA2

Nikolai wrote:

At some point certain cameras (advanced P&S, like Sony DCS Fseries) used to through what looked like a dim laser web pattern to help their AF systems. I understand the trend was kinda shut down due to 9/11 and consequent security elevation. However I do thing the idea was great, since the beam was retatively low-intensity and non-intrusive, however it helped a great deal in the scarcely lit and dim wedding venues,
I'm wondering is there is a flash-light-like tool the market that could be used next to any camera to hel with AF by emiiting similar laser pattern.
I know there are plenty of laser pointers, may somebody figured out some beam splitting device to attach to them?
What do you think/know?

Canon flashes (430 and 580) emitt a red line pattern for autofocus assist, as does the ST-E2. Is this not as intense as what you've seen elsewhere?

Nikolai

Richard wrote:

I'm not sure an external beam would help without the AF system being programmed to expect it. Are you using the flash AF-assist light? That seems to work pretty well for me.

AFAIK, focusing system of most dSLRs operates simply based on contrast. It doesn't care when this contrast comes from. Razor-thin laser beams are ideal for it.

Nikolai

BenA2 wrote:

Canon flashes (430 and 580) emitt a red line pattern for autofocus assist, as does the ST-E2. Is this not as intense as what you've seen elsewhere?

Ben (and Richard), my hotshoe would be already taken by PocketWizard, hence the need for standalone device.
Shay uses small but rather bright LED flashlight, but I personally think it's a bit intrusive and can "spook" the subjects...

BenA2

Nikolai wrote:

Ben (and Richard), my hotshoe would be already taken by PocketWizard, hence the need for standalone device.
Shay uses small but rather bright LED flashlight, but I personally think it's a bit intrusive and can "spook" the subjects...

I see. I purchased an ST-E2 just to solve this problem, but at the time I wasn't using flashes, so I had no other hotshoe conflicts. Before I bought it, though, I looked for alternatives and wasn't able to find any that wouldn't require a lot of DIY ingenuity and time.

I agree that a bright LED is a little intimidating to subjects. But, if you're shooting paid models, which it appears that you are, couldn't you explain it to ease their concerns?

I hope you're able to find something that works.

Nikolai

BenA2 wrote:

I see. I purchased an ST-E2 just to solve this problem, but at the time I wasn't using flashes, so I had no other hotshoe conflicts. Before I bought it, though, I looked for alternatives and wasn't able to find any that wouldn't require a lot of DIY ingenuity and time.

I agree that a bright LED is a little intimidating to subjects. But, if you're shooting paid models, which it appears that you are, couldn't you explain it to ease their concerns?

I hope you're able to find something that works.

You are totally correct, it's not an issue for the models (after all, they don't call it "modeling light" for nothing ).
However, I do some other stuff except modeling, too...
Oh well, I guess it's DIY time again.. I think I saw some el cheapo laser pointers for kids with geometrical patterns attachements...

darkdragon

I think something like this laser pointer with interchangable heads would be useful. I use to have one and the heads come in different patterns. So maybe a flower pattern would be good to help focusing?

I got that link with a quick search on amazon to illustrate my point, check your local Spencer Gifts, party store, electronics megastore (Fry's)...places like that. These laser pointers are cheap now and some come with as many as 15 different tips with different patterns.

Nikolai

darkdragon wrote:

I think something like this laser pointer with interchangable heads would be useful. I use to have one and the heads come in different patterns. So maybe a flower pattern would be good to help focusing?

I got that link with a quick search on amazon to illustrate my point, check your local Spencer Gifts, party store, electronics megastore (Fry's)...places like that. These laser pointers are cheap now and some come with as many as 15 different tips with different patterns.

Yep, something like that. Thanks!

Manfr3d

Nikolai wrote:

AFAIK, focusing system of most dSLRs operates simply based on contrast. It doesn't care when this contrast comes from. Razor-thin laser beams are ideal for it.

Absolutely! Thats why I always carry a small laser pointer (keychain type)
in my bag when I head out for some night photography. It really helps to
the camera to focus. I am not using this method when I shoot people,
there the assist beam of my flash is the tool of choice.

ziggy53

The Sony F828 used a holographic red laser grid for its autofocus and could indeed allow focus in zero ambient light. Pretty advanced stuff in its day.

If you use a camera that has both a hotshoe and a PC connector I think you could use a hotshoe flash with AF assist light, like the Canon 580EX and 430EX or ST-E2 or Sigma 500/530 DG Super series flashes, and then use the PC port for triggering the PocketWizard via an adapter.

If you want to create your own device, I found some cheap red LED flashlights and mounted a simple plastic lens on one to give a better beam, more suitable for AF. I tried it with my Minolta A2 digicam and it worked pretty well. A true laser pointer may be too collimated and bright to be safe if directed into eyes. You might need to stack a couple of those pattern generators onto the front to get the beam down to safe levels.

Nikolai

ziggy53 wrote:

The Sony F828 used a holographic red laser grid for its autofocus and could indeed allow focus in zero ambient light. Pretty advanced stuff in its day.

If you use a camera that has both a hotshoe and a PC connector I think you could use a hotshoe flash with AF assist light, like the Canon 580EX and 430EX or ST-E2 or Sigma 500/530 DG Super series flashes, and then use the PC port for triggering the PocketWizard via an adapter.

If you want to create your own device, I found some cheap red LED flashlights and mounted a simple plastic lens on one to give a better beam, more suitable for AF. I tried it with my Minolta A2 digicam and it worked pretty well. A true laser pointer may be too collimated and bright to be safe if directed into eyes. You might need to stack a couple of those pattern generators onto the front to get the beam down to safe levels.

That's what ND filters are for

Manfr3d

There is a nice LED Hotshoe lamp from Hama, maybe that's a solution?



Source: http://www.7dayshop.com/catalog/product_info.php?products_id=100997

Nikolai

Manfr3d wrote:

There is a nice LED Hotshoe lamp from Hama, maybe that's a solution?
Source: http://www.7dayshop.com/catalog/product_info.php?products_id=100997

1) intereresting idea
2) it takes the hotshoe...

Manfr3d

Nikolai wrote:

2) it takes the hotshoe...

You could use a flash bracket:

Scott_Quier

Nik - in reference to Shay's solution being too bright/intrusive - how about just dimming it down with a gel? Putting a full CTO on it (or something similar) would get you the light you need without the glaring blue light. Just a thought.

Nikolai

Scott_Quier wrote:

Nik - in reference to Shay's solution being too bright/intrusive - how about just dimming it down with a gel? Putting a full CTO on it (or something similar) would get you the light you need without the glaring blue light. Just a thought.

Hmm.. Flash bracket and a gel... interesting... Thanks guys!
If my laser pointer solution doesn't materialize this would be another one to try...

jziegler

darkdragon wrote:

I think something like this laser pointer with interchangable heads would be useful. I use to have one and the heads come in different patterns. So maybe a flower pattern would be good to help focusing?

I got that link with a quick search on amazon to illustrate my point, check your local Spencer Gifts, party store, electronics megastore (Fry's)...places like that. These laser pointers are cheap now and some come with as many as 15 different tips with different patterns.

I've seen these at dollar stores and flea markets, sometimes with closer to 30 different patterns. They work great for exercising cats, but I don't know if they'd work well for focusing a camera.

jziegler

ziggy53 wrote:

A true laser pointer may be too collimated and bright to be safe if directed into eyes. You might need to stack a couple of those pattern generators onto the front to get the beam down to safe levels.

Red laser pointers generally are safer than the other colors. Anything that is a class II laser is considered eye-safe (you will blink before it causes any damage). The higher powered IIIa laser pointers (apparently becoming the most common) could cause eye damage, but will likely still cause a blink reflex in time. If you can find a class II pointer, you have no worries.