# EXIF Files



## gringolocophotography (Jan 9, 2020)

I read that when I look in the EXIF file under Metadata that it would show me how many stops off on exposure my photo was but I am unable to see that. All I see is if the Exposure Bias was used. Please help me out here.  Thanks


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## Linwood Ferguson (Jan 9, 2020)

I'm not familiar with anything similar to what you are looking for, can you tell me where you read it, perhaps a snippit or copy from that document?   Exposure bias is, if you shoot in auto-exposure, how much you asked the camera to under- or over-expose relative to its target.  What you are describing sounds more like you expect it to tell you something about the result? 

Now in develop (I'm not aware of it saving in metadata) you can see how much you have adjusted it in post processing, is that what you mean?


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## gringolocophotography (Jan 9, 2020)

I had found this reading


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## Jim Wilde (Jan 9, 2020)

I think you've misunderstood....Rob was talking about "Exposure Bias" only, which is all that LR can show you. His comment that the Metadata Panel "shows that I underexposed by 2 stops" means that he set the Exposure Compensation in camera to "-2", and that was shown in the Metadata panel.


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## Linwood Ferguson (Jan 9, 2020)

OK, exposure bias is a request to your cameras auto-exposure system to over, or under expose by a given amount. An bias of -2 would under-expose by 2 stops.


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## gringolocophotography (Jan 9, 2020)

ok so I only shoot in manual mode so is there a way in Lightroom to see by how many stops I missed the perfect exposure


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## Linwood Ferguson (Jan 9, 2020)

I am not aware of a way.  Besides, "perfect" is a matter of opinion.   

If you adjust the image to your liking with the exposure slider, then how far you move it is one indication (I'm not aware of a place to see that in library, only develop).


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## gringolocophotography (Jan 9, 2020)

For sure I understand that "perfect" is different to every person but I was wondering if there is way to see how many stops from "0" on the light meter the photo was either under or overexposed


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## Jim Wilde (Jan 9, 2020)

You could hit the Auto button to see what Lightroom thinks about the exposure....


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## gringolocophotography (Jan 9, 2020)

ok great here is what LR says when I hit auto for the photo. By the figures how do I calculate how many stops my exposure was off?


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## Philippe Coudé du Foresto (Jan 9, 2020)

The best thing to look at to see if your photo is over or under exposed is the histogram. It won't tell you by how much tough, but once you'll have adjusted the exposure with the cursor in the developpement module, you will know.


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## gringolocophotography (Jan 9, 2020)

All of my sports photos are usually underexposed because of the poor lighting conditions. I can usually fix them in post processing but I would like to know how many stops I am fixing just for informational purposes


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## Linwood Ferguson (Jan 9, 2020)

I don't know of a way to see that.  My guess is some cameras may be storing light meter readings in the maker notes or other places, but I see no where that comes through to LR.


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## gringolocophotography (Jan 9, 2020)

ok I asked the canon people yesterday and they said that the light meter readings are not stored. I guess the only way will be before taking the photo by looking at the light meter


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## Linwood Ferguson (Jan 9, 2020)

Well, the number you adjust is known to lightroom.    You might look at JF's data explorer and see if one of the items in there let you see the exposure slider correction amount.  That's different from what the camera light meter showed, but it is what your correction showed.  I just don't know if you can get to what LR knows.


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## Philippe Coudé du Foresto (Jan 9, 2020)

The best mean to detect and correct under (or over) exposition is to use the histogram on your camera.


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## gringolocophotography (Jan 9, 2020)

what is "JF's" data explorer?


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## Hal P Anderson (Jan 9, 2020)

It's a LR addon by _Jeffrey Friedl_


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## Paul_DS256 (Jan 9, 2020)

gringolocophotography said:


> I read that when I look in the EXIF file under Metadata that it would show me how many stops off on exposure my photo was


Back to your original question, I think you are asking for the camera to say where you screwed up a shot and store the correct exposure you should have used. Doesn't exist because the camera simply records what the settings where. It does NOT store what the the settings would have been had you been in 'auto' mode instead of manual.



gringolocophotography said:


> All of my sports photos are usually underexposed because of the poor lighting conditions


That is where you need to find out what the exposure would have been better. And of course, the correct exposure is going to be in relation to trilogy of shutter+aperture+ISO.  So, for example, if you shoot in shutter priority, with a floating ISO, the exposure will be based on what the camera thinks it should be in relation to the ISO it chooses.


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## Paul_DS256 (Jan 9, 2020)

As an FYI, here's a list of the MAKERNOTES metadata Canon records on it's images Exiv2 - Image metadata library and tools


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## MarkNicholas (Jan 9, 2020)

gringolocophotography said:


> ok so I only shoot in manual mode so is there a way in Lightroom to see by how many stops I missed the perfect exposure


There is no such thing as a perfect exposure. On what basis can such perfection be determined  ? Every exposure mode on your camera will result in a differently exposed photo. Who is to say which is the correct exposure mode ? If exposure perfection could be determined then every camera would be manufactured to produce the perfectly exposed photo every time and there would be no need for all those pesky knobs and dials.


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## Linwood Ferguson (Jan 10, 2020)

MarkNicholas said:


> There is no such thing as a perfect exposure. On what basis can such perfection be determined  ? Every exposure mode on your camera will result in a differently exposed photo. Who is to say which is the correct exposure mode ? If exposure perfection could be determined then every camera would be manufactured to produce the perfectly exposed photo every time and there would be no need for all those pesky knobs and dials.



Yeah... but to the OP's original question, I think it's a valid point.  IF (emphasis on "if") the camera recorded its own exposure settings if in an auto mode, that's interesting how much that differs from what was used.

On the other hand, I maintain that, in post processing raw which the OP appears to be doing, the exposure slider is used to (say) increase exposure by 1 stop, then that's a fair indication of the same thing -- this time based not on the light meter but on the OP's eye.   So if you go through 100 shots, and find 20 were increased by 2 stops, 50 by 1 stop, 20 were right, and 10 were decreased by 1 stop -- well, you have learned something, that you more often under-than-over expose.  Is that useful to you?  Might be.  Might not. But that info is available -- whether LR will actually show it to you easily I do not know.


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## Conrad Chavez (Jan 10, 2020)

gringolocophotography said:


> All of my sports photos are usually underexposed because of the poor lighting conditions. I can usually fix them in post processing but I would like to know how many stops I am fixing just for informational purposes


We need to get away from thinking that the exposure metadata or Exposure Bias metadata is relative to a "perfect" exposure.

It's relative to the automatic exposure level calculated by the exposure meter, and the meter is influenced up or down by things like:

Whether the subject is in the frame where the exposure meter thinks it’s important enough to influence the meter. For example, in a sports photo, the less of the frame a player occupies, or the less the player is in an area highly weighted by the exposure meter, the less likely it is that the player will be properly exposed because the brightness of the rest of the frame will mislead the meter more.
What metering mode your camera was set to; Matrix will calculate a different automatic exposure level than Spot, Center-Weighted, Average, etc.
Because it’s so easily influenced by so many decisions you made either consciously or not,  the automatically calculated exposure level is often not the “perfect” exposure.

In a sports example, if you want to expose a player correctly but the player is frequently against a light background like a court or white gym walls, the brightness of the background might influence automatic exposure to lower the exposure so much that the foreground (the actual subject) gets under-exposed. That is not a "perfect" exposure, so to improve the exposure a photographer would do some initial test shots and check the histogram. If the histogram indicates that the exposure range was shifted too far to the left (dark) side, the photographer will override automatic exposure by increasing Exposure Compensation, and retesting until the histogram indicates that the foreground is exposed as intended.

That’s what Exposure Compensation really is. It’s not how far you are from the “perfect” exposure, it's you _overriding_ the camera’s auto-exposure calculation to get your actual exposure closer to your intended exposure.

The camera’s automatic exposure can be “perfect” only if you can confirm that all of the assumptions fed into the camera are perfect. The less that’s true, the less perfect the exposure it.

If I understand Lightroom correctly, the Basic panel Exposure setting units are in EV (standard Exposure Value), the same EV units used by the exposure meter in the camera. If you are consistently having to set the Exposure setting to +2 on many photos to make them look good in your eyes, I think that means the photos are consistently being shot 2 stops too low. That would suggest that next time you shoot an event, try aiming for a camera meter EV that’s 2 stops higher than you have been in the past.

And it’s important to notice that the amount you have to move the Exposure slider might be different than the amount of Exposure Compensation indicated in the metadata. Because again, the camera’s idea of auto exposure might not line up with what you think actually looks good. So any difference there can also be an indication that you might try different in-camera settings (such as Exposure Compensation)  to get the in-camera exposure closer to what you intend.



gringolocophotography said:


> ok so I only shoot in manual mode so is there a way in Lightroom to see by how many stops I missed the perfect exposure


In Manual exposure mode, if the meter indicates you’re above or below, that only means something if you understand what the camera’s exposure system  was told to assume for the calculation (which mode, what framing, whether the best light is where the subject actually is, etc.). Again, that makes it hard to know whether the Exposure Compensation value displayed in Lightroom is useful. But when you instead use the other method —  look at how far you had to move the Exposure slider in Lightroom — the nice thing is that it works no matter what exposure mode you set the camera to.  Whether you shoot in Manual, Program, Aperture Priority, or Shutter Priority mode, if you had to set the Exposure slider to +2 to get it to look right, that means the exposure should have been 2 stops higher in camera…no matter how you set the camera.

If you were 2 stops under in Manual mode, then next time you go out and shoot, you then choose how you want to push the exposure value up by 2 stops: by manually shifting your shutter speed, aperture, or ISO value.

(If the camera is in an automatic mode, you shift Exposure Compensation  up by 2 stops, and it will get there by shifting the variables that aren’t locked in the current exposure mode.)


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