White flashing (shooting raw)

[danny842003]

So i took some shots with my 550D in RAW mode and on the display when viewing with the histogram screen areas which im guessing were overexposed are flashing white.
Viewing them on aperture the areas appear totally white. is there any way to correct this? What does it mean at a loss being a newbie.

 

[huffy]

You are right about what you are guessing. the white flashing areas (blinkies) are areas that have been overexposed. The only way to correct this is to expose correctly when taking the picture, you cannot change it in a photo editing program as the camera has recorded those points as pure white pixels.

If you are unsure about exposures and metering have a look at the tutorial sections on this site.

I hope this is of use
http://www.talkphotography.co.uk/forums/forumdisplay.php?f=23

 

[k4stn]

Hi Daniel

If you are shooting in AV,TV or P you can press the (exposure compensation)AV+/- button and move it left until the blinking stops (over exposed) or right (under exposed)

 

[weybourne]

To add to the above, blown highlights (as they're known) aren't always avoidable - especially if there's a big range of light conditions in the frame to expose for. Sometimes you have to decide if they are 'acceptable' or not (they can even work well in a high-contrast b&w shot). Sometimes they can be 'rescued' on the computer (but, as is said above - there's not a lot you can do with total white), . Sometimes graduated filters or bracketed exposures can be utilised (on the pc) to work with such wide ranges of light conditions.

 

[tdodd]

When you shoot raw, depending on the capabilities of your raw software, it might be possible to regain detail in the highlights if they aren't too far gone. With JPEG files this option is gone for good. With raw you might be lucky. In fact it is a good technique to push the exposure (histogram) over to the right until you are on the borderline of clipping and a little clipping may very well be perfectly OK.

Here's a fairly extreme example of highlight recovery in a subject which was substantially overexposed, but a raw file and Lightroom meant that lots of detail could be salvaged. In the "before" image the red areas are all clipped to white and would have been flashing black/white in your camera...

Have a look at the raw tutorial for more info - http://www.talkphotography.co.uk/forums/showthread.php?t=210392.

 

[HoppyUK]

So i took some shots with my 550D in RAW mode and on the display when viewing with the histogram screen areas which im guessing were overexposed are flashing white.
Viewing them on aperture the areas appear totally white. is there any way to correct this? What does it mean at a loss being a newbie.

Edit: crossed post with Tim - been making a cuppa

What you have discovered is the highlight alert over-exposure warning, known as 'blinkies' and it's one of the most valuable exposure setting tools. Blinkies are enabled in the menus and work in both JPEG and Raw modes.

The news may not be as bad as you think. The blinkies certainly flash on blown areas, but they also flash on areas that are on the brink of blowing, as a warning. Furthermore, if you're shooting Raw, there is always a bit more highlight headroom available than when shooting straight to JPEG, so you may well be able to recover some areas that appear to be blown, but aren't quite.

With blinkies on (always a good idea) you will almost always find that they flash on some areas, even when exposure is correct - things like bright reflections etc, and often on bright skies. You then have to make a judgement on what to do about it - either leave it and let them blow if unimportant, or reduce exposure to bring the highlights down, though that may well under-expose other areas.

Unfortunately, correct exposure does not mean perfect exposure of everything and some subjects just have too great a dynamic range (range of tones from brightest to darkest) that the sensor is able record. Adding a graduated filter to over-bright skies is a possibility for landscapes, using fill-in flash for strongly back-lit portraits is another good technique.