IR with custom WB and other help needed?

[Brotage]

alright, I got an IR filter when I bought my camera at christmas, been LOVING it so far..

anyway I live in minnesota, it's cold and I really hate bringing my camera around in below zero weather.

This weekend it's supposed to get around 30 so kinda warm. Theres this really cool place under a highway called "graffiti graveyard" theres one highway ramp, and then a space, and then another highway ramp so you can get sunlight. anyway, I wanna try it in IR.

First, I tried IR once, horribly failed. couldn't get custom WB right.

I know I point it at the sky or grass and take a pic. But do I have to expose it properly with the filter on for WB to work. Or do I just snap, and set that one to WB?

any other thing I need to know before I try?

Yes, I have a tripod.. and going to shoot in RAW

 

[Sideburns]

you're confusing WB with metering.
WB you take a picture of something white.
Metering you can meter off green grass.

 

[SCHNOOBS]

What DSLR do you have and what is the Megapixal? There may be a problem...

 

[Brotage]

I mean some IR things I've read said you point it at the grass or sky and take the picture, and use that for custom WB. And then take the real IR picture, using the previous to set the WB correctly.

I'm just asking if I have to expose the grass/sky picture properly for the WB to be right.


maybe I just didn't read your post right

EDIT; a rebel XTi and it has 10 some MP? I dont see why that would matter

 

[AluminumStudios]

I don't know if it's the same for Canon, but I just set my Nikon in aperture priority mode when I take a photo for custom WB and that usually works. If the photo it takes isn't good for custom WB my camera tells me. The exposure doesn't matter too much, as long as it's not horribly under exposed or whited out.

 

[Brotage]

Yeah but with the IR filter on my camera you can't see anything. it's a DEEP DEEP red. and you have to have a couple second exposure for it to be properly exposed (in sunlight).

So do I just snap and use the nothing-but-red picture for custom WB

or do I expose it properly (a couple seconds) and use that for custom WB?

 

[SCHNOOBS]

Inside a camera, there is a specific setting of the sensor that can be taken out to make it strickly IR, I forget exactly what its called, but it generally sets you back around $500 to get that adjustment made to the camera itself. the problem with the mp on the camera is that this specific sensor cannot be chgned over to IR if the camera itself is 10mp or above, go to Maxmax.com

 

[Arch]

ok what you need to do for best results is set the wb from a well lit patch of grass, dont use the sky or white card or anything else.

To do this the best way do the following:
- put your cam on a tripod pointing at a well lit area of green grass.
- focus the shot
- turn off auto focus
- place the IR filter on the cam
- make sure your on custon wb
- try a 2 sec exposure to take the reading
- your cam should tell you if it accepts the new custom wb or not
- if it doesn't try again with a longer shutter speed

 

[Mike_E]

In Minn., you may want to take a 3 foot by 3 foot square of astro-turf though.

I could be wrong but I think the point is to get your WB from the equivalent of an 18% grey card.

Is that right folks?

 

[Brotage]

Inside a camera, there is a specific setting of the sensor that can be taken out to make it strickly IR, I forget exactly what its called, but it generally sets you back around $500 to get that adjustment made to the camera itself. the problem with the mp on the camera is that this specific sensor cannot be chgned over to IR if the camera itself is 10mp or above, go to Maxmax.com

you don't need to have the IR filter over the sensor removed to do IR shots. You just need a filter a tripod and a couple second exposure.


and thanks arch, thats what I was looking for

 

[Garbz]

the problem with the mp on the camera is that this specific sensor cannot be chgned over to IR if the camera itself is 10mp or above, go to Maxmax.com

errr... <- says it all.