How to avoid Clipping in Highlight with a 5D with iso Auto

Hello Every body,

do you know anyway to prevent from clipping the highlights with a Canon DLSR ?

I know we can show a warning while we are taking a picture, but I'm looking for a way to calculate the max ISO before it clips...

Any idea ?

Calculate the max ISO before it clips? This is confusing, especially since you are asking about auto ISO. Up until a certain point (usually 6400 ISO on most cameras out of the box) the camera will choose your ISO for you when you set it on auto ISO. So regardless of your other settings (again, up until a certain point) the camera will make your exposures to what it sees fit when auto ISO is set.

Not a mind reader, but I'll do my best. When you have the 5D in auto ISO you believe it automatically is clipping the highlights is what I believe you are saying. So based on it's computer brain, what it's seeing as a proper exposure you are seeing as clipping highlights. A few things to look at could be: 1. Check your metering mode. If you are in spot metering (I believe center spot is all Canon offers) and something dark is in the center of your frame, your camera will automatically expose the image so that dark part is "proper exposure". This will most definitely result in highlight clipping. 2. If you think the whole image is being over exposed you could either set the ISO to be controlled by you manually, or use exposure compensation to make the camera slightly underexpose. 3. Finally, if shooting in a high contrast situation, the camera won't be able to get everything exposed properly whether in auto ISO or full manual mode. However, if in auto, it will have to make a choice whether to expose for the highlights or for the shadows. A lot of this choice will once again be based on your metering mode.

My advice would be to use evaluative metering if using auto anything. That way the camera can look at the light across the whole scene and choose how to expose properly. This won't solve all your problems, but it may help.

99% of the time I use full manual, not Auto anything, to take full control of the exposure & suggest that you read this: Need an exposure crutch?

all of the 5D cameras have highlight alerts in custom functions. Turn Highlight alert on and the highlights will blink in your viewfinder when you clip them

umphotography wrote in post #18565625
all of the 5D cameras have highlight alerts in custom functions. Turn Highlight alert on and the highlights will blink in your viewfinder when you clip them

He said he knew that.

It would be cool if a camera could be set to expose ETTR (without clipping) automatically instead of to an average 18% gray.

• The determination of clipping status cannot occur until the sensor has been exposed.
  
• In all cases of reflected light metering, the metered zone is simply measured for brightness...there is no assessment of where clipping would be simply because the meter knows only 'the middle of the histogram' reading of this point is EVn, it has no way to know where clipping is relative to EVn.
  
• If you averaged together each of the metering zones, it still has no way to know where clipping is...it might be 3 pixels away from the measurement area!
  

Impossible, quite impossible with the current state of artificial intelligence. Until someone programs a camera that can tell a clipped white wedding dress from a clipped white ceiling/wall, the camera will not be able to help with this. That is the photographer's job.

If the only desire is to avoid any and all highlight clipping, shoot in spot metering, meter the brightest part of the scene, and release the shutter. Your high-contrast photos will look like crap, but they won't be clipped.

Honestly, the question itself reminds me of:
What is wrong with my camera? I'm shooting in Program mode with AUTO-ISO and ETTL-II flash...

With today's light metering sensors having resolutions like 360000 pixels, it would be possible to analyze the whole image before shooting, and adjust exposure accordingly. Thus highlight clipping could be avoided. But the main problem is of course to realize that the particular small reflection of the sun in a window should perhaps not be regarded, since it renders the rest of the image black.

apersson850 wrote in post #18565816
With today's light metering sensors having resolutions like 360000 pixels, it would be possible to analyze the whold image before shooting, and adjust exposure accordingly. Thus highlight clipping could be avoided. But the main problem is of course to realize that the particular small reflection of the sun in a window should perhaps not be regarded, since it renders the rest of the image black.

Which is exactly why the photographer matters.

Best way is to use Auto modes with exposure compensation set at zero

Minimum shutter speed at 1/125 (or what ever you choose) and auto ISO will never let your blinkies engage. AV will always get you there, then when you know the exposure you can dial in with M if you desire.........Camera is always smarter than the photographer

Thanks a lot everybody for your answers ! There are nice advises !

Ok I guess there is no direct solution in Canon's menus.

The spot metering is a good solution, in few seconds you can adjust, but sometimes actions is faster and requires to shoot instantly.

90% of the time I shot in manual mode. I know well my camera, so I can adjust the settings in 2 or 3 seconds max. I use the spot metering with exposure compensation set to 0, and first look at my subject to expose for him, and try to get it at postiion 0 in my light meter. Then I look at the brightest part of the scene. If the light meters move to the right over +1 max +1,5, I know it will be clipped I will underexpose my shot and recover the shadows in post process. If I know there will be no way to recover shadows I will use bracketing.

Also looking at the brightest area, I can press the * button to lock the exposure in ISO auto and recompose.
I tested as well the Magic Lantern firmware, who has this function to avoid clipping, but it didn't really work.


I think it is a pitty in 2018, that this function doesn't existe natively.

Thanks dude, I will try this method ! It should work well

Yes totally, these kind of situations would complicate the task for an auto mode. Maybe to allow a kind of tolerance for sun, and bulbs...

Yes checking in live view is a solution. Well there several methods. But I just wondering what is the fastest one !

Yes this is the function that is missing in Canon's cameras. I think it shouldn't be so complicated to create.