Focusing at night

[jiveturkey]

I recently bought a PT-010 housing but haven't had a chance to test it at night. My question is how does the camera focus at night? I guess if you're using the auto focus the preflash gives it enough time to focus? Is that right? What if you're using manual functions? I really love night diving. I'd like to be able to use my camera at night but unfortunately I can't afford a strobe right now.

 

[Dee]

Topside there's a small focusing light that comes on to help with that. But in the housing that light is blocked. I mount a small LED light under my camera for focusing purposes. It's bright enough to help with the focus as well as spotting stuff yet it doesn't cause a hot spot in the photo.

There several lighting options and mounting options. Just make sure there's no strong spotlight.

Tip: To remove the spot, line the reflector with crumpled foil.

 

[TheAvatar]

I would signal my budy to shine his dive light on the subject. It is definately not the best solution all the time. It worked for me.

 

[ReyeR]

No the pre-flash will not help it to focus.

Here's a nifty little device for the UK2 eLED light:
http://www.uwdigitalcamera.com/English/eminilight.htm

Some strobes like the DS125 has a built-in modelling/focussing light as well.

 

[blacknet]

Hello,

this is an all to common problem with any camera. The autofocus will fail in a number of situations. The best thing to do is use a pre-focus, I have detailed this in the tips/techniques thread entitled "Composition tips. a.k.a. "where did the rest of my subject go?" " it's a very simple technique and will help improve your shots.

Ed

 

[Dee]

ReyeR...the LED light shown in your link is a Princeton Tec Attitude. It's the same one I mentioned above. I like it so far.

 

[jiveturkey]

Thanks for the responses guys. I'll hopefully be doing a night dive this weekend so I'll have to stick with using a dive light until I can get me a LED. I guess I'll find out soon enough how well it works.

 

[notabob]

Dee, have your LED lights ever flooded on you? Both of mine have - one on its very 1st dive, the other on its 3rd or 4th. Actually the 2nd light cracked on its final dive, even though the depth did not exceed 125ft. They work great, as far as producing a nice light, but at $16-$20 a pop, I don't want to keep replacing them all the time.

Has anyone come across an alternative small LED light? Something not made by Princeton?

-Roman.

 

[kelpdiver]

Mine basically lives in my drysuit pocket (including the wash/rinse/dry cycle) so I always have it with me, meaning it's been down scores of times without a problem, other than when I don't unscrew it enough to prevent water pressure from accidentally turning it on. I've had buddies tell me it was turned on in my pocket the whole dive. But with the battery life of LEDs, not a problem. Guess it's time to buy another to attach to my new strobe...
Personally I've had more problems with UK lights.

 

[kelpdiver]

Well, I've got the Impact, which may be a little large (like Jumbo Shrimp??) for a focusing light, and may be constructed better than the Attitude???