Settings to show difference in LED colors

[percula99]

Hi, I am not good with a camera so I need some help with settings. I replaced all the CREE royal blue and cool white LEDs in my fixtures. One of the royal blues was defective, and for warranty coverage I need to show the defective LED alongside the working LEDs.

I have a Canon Power Shot S5 IS camera. I have tried every F stop, shutter speed and shooting mode available, but all my shots turn out the same. I can't tell the difference between the blue LEDs and the white. See photo below. If you look at the back row, the middle lit up light is white and all the other lit up lights are blue, but they look identical. What settings would I need to use to show the color difference?

[URL=http://s30.photobucket.com/user/percula99/media/IMG_0055_zps114f9530.jpg.html][/URL]

 

[GrindingNemo]

Try dimming your lights way down. Go very high at all and you will saturate the sensor and get the problems your having now.

 

[IslandCrow]

Increasing the shutter speed will have essentially the same effect as well. As GrindingNemo stated, the sensor is simply getting flooded with light and oversaturating the photo receptors, so everything looks white. It's referred to as "clipping" the highlights. If you expose properly for the lights (i.e., everything else will be very underexposed), you'll be able to see the difference in color.

 

[rovster]

I'm assuming this is what you want to do?




Like mentioned above, you just need to severely underexpose the image, for me, that meant using a very high f-stop.

 

[percula99]

Thanks guys. I tried lowering the lights but that did not do it. I also tried every fstop on my camera to no avail. I finally tackled the problem in Photoshop. I adjusted the auto level, auto contrast and color balance until I could see the difference between the blue and white. The company accepted the evidence I provided and have sent out a replacement.

 

[IslandCrow]

Glad the company was good with what you gave them. For future reference, increasing shutter speed usually gives you more latitude than f-stop. That said, I was also assuming that you're shooting in a full manual mode. If you're adjusting f-stop, but the camera is selecting the "appropriate" shutter speed, you're going to continue to run into the same problem because the camera is trying to average out the exposure rather than exposing for just the lights.