Underexposed DNG Files

GeoJerry · 05-31-2013, 02:52 PM

I've noticed when I shoot RAW that the resulting DNG image is usually 1-2 stops underexposed relative to the correctly exposed embedded jpeg. Is this normal, or am I doing something wrong?

Na Horuk · 05-31-2013, 03:04 PM

Hm, do you have a custom filter turned on? The "jpeg style" or "digital filters" can affect perceived brightness. Especially if you have it set to "bright." If you want the jpegs to look as much like the raw as possible, set it to neutral or natural.

stormtech · 05-31-2013, 03:07 PM

I think it depends a lot on which editor you are using. I've found the same when I use Acdsee Pro 6 - the PEF is 1.5 - 2 stops underexposed compared to the embedded JPEG. When I open the same file in Lightroom 4.4 I don't see this change - at least not as dramatic.

I have my jpeg settings to the default "Bright" mode - I am guessing that if I had the jpeg settings to all neutral the raw and jpeg would be more similar.

Edit: Na Horuk was posting the same time as I was.

GeoJerry · 05-31-2013, 03:26 PM

Originally posted by Na Horuk

Hm, do you have a custom filter turned on? The "jpeg style" or "digital filters" can affect perceived brightness. Especially if you have it set to "bright." If you want the jpegs to look as much like the raw as possible, set it to neutral or natural.

Digital filters is set to off (default for RAW shooting), but I don't see any menu item call "jpeg style." Is that unique to different cameras (I have a K-5)? Or are you referring to the control to the right of the OK button? I had that set on Vibrant with +2 high key. Maybe that was it? I'll try, thanks!

GeoJerry · 05-31-2013, 03:27 PM

Originally posted by stormtech

I think it depends a lot on which editor you are using. I've found the same when I use Acdsee Pro 6 - the PEF is 1.5 - 2 stops underexposed compared to the embedded JPEG. When I open the same file in Lightroom 4.4 I don't see this change - at least not as dramatic.

I have my jpeg settings to the default "Bright" mode - I am guessing that if I had the jpeg settings to all neutral the raw and jpeg would be more similar.

Edit: Na Horuk was posting the same time as I was.

OK sounds like you're both on the same track. I use Aperture, but I can try importing a jpeg directly into Topaz as well.

Thanks!

stormtech · 05-31-2013, 05:10 PM

Originally posted by GeoJerry

Digital filters is set to off (default for RAW shooting), but I don't see any menu item call "jpeg style." Is that unique to different cameras (I have a K-5)? Or are you referring to the control to the right of the OK button? I had that set on Vibrant with +2 high key. Maybe that was it? I'll try, thanks!

Yes - the button to the right of the OK button.

The settings there, called the custom image function I think, controls the jpeg output for the camera. But, when you shoot raw, the camera has to provide a jpeg image for you to view on the LCD screen, and for preview in editors. This embedded jpeg is controlled by the custom image function.

I am not sure about this part, but I think that some editors will read these settings when opening a raw file while others will not. Like I said, I am sure that Acdsee does not, but it seems like Lightroom might since I see a distinct difference when opening the same raw file in each editor.

**dms** · 05-31-2013, 05:53 PM

(1) Try playing with the jpg options--increase contrast, etc.--to get a version that is closer to blowing the highlights at similar exposure does in camera raw. There are posts on this.
(2) And/or just bias the exposure by the number stops needed--e.g., get enough testing under controlled conditions so you know what to do.
Unless strong reasons to counter--for wide DR subjects--you should be exposing to the right--just shy of blowing the highlights--or even just blowing them sometimes--to get maximum quality.

reeftool · 06-05-2013, 07:18 AM

I've noticed a big difference in the exposure appearance from the LCD on the camera when I get them uploaded which is most likely a brightness setting issue. My monitor brightness is turned down to get close to printer output while my camera LCD brightness level is pretty bright. I tend to trust the histogram rather than the screen. Most of your camera JPEG options won't show up on your RAW photos after you upload but I'm pretty certain they are in effect in regards to the image you see on the camera LCD.

IchabodCrane · 06-05-2013, 07:24 PM

Originally posted by GeoJerry

I've noticed when I shoot RAW that the resulting DNG image is usually 1-2 stops underexposed relative to the correctly exposed embedded jpeg. Is this normal, or am I doing something wrong?

Do you have Highlight Protection turned on? This will automatically cause my RAW files to be exactly 1 stop underexposed (which is exactly what the camera is doing) while the software (Aperture), apparently, doesn't detect that it needs to adjust the brightness by one stop.

GeoJerry · 06-05-2013, 10:17 PM

Originally posted by reeftool

I've noticed a big difference in the exposure appearance from the LCD on the camera when I get them uploaded which is most likely a brightness setting issue. My monitor brightness is turned down to get close to printer output while my camera LCD brightness level is pretty bright. I tend to trust the histogram rather than the screen. Most of your camera JPEG options won't show up on your RAW photos after you upload but I'm pretty certain they are in effect in regards to the image you see on the camera LCD.

Each RAW image has an associated JPEG image embedded within it. The JPEG is what you see on the LCD and, for a brief moment (in Aperture anyway), on the monitor when the image is first uploaded to your PC. I'm not having any issues with the JPEG images on the LCD or monitor, just with the RAW image which underexposed. I think you're right about the options not affecting the RAW image.

GeoJerry · 06-05-2013, 10:19 PM

Originally posted by IchabodCrane

Do you have Highlight Protection turned on? This will automatically cause my RAW files to be exactly 1 stop underexposed (which is exactly what the camera is doing) while the software (Aperture), apparently, doesn't detect that it needs to adjust the brightness by one stop.

I think you got it! I did have this setting set to On. I shot three bracketed images. I turned it off and shot three more. The latter three RAW images seem much truer to the JPEGs I see in the LCD. Thanks!

stormtech · 06-05-2013, 11:00 PM

Originally posted by GeoJerry

I think you got it! I did have this setting set to On. I shot three bracketed images. I turned it off and shot three more. The latter three RAW images seem much truer to the JPEGs I see in the LCD. Thanks!

Good catch to IchabodCrane - I didn't think any of those settings affected raw - only jpeg. Good to know.

IchabodCrane · 06-06-2013, 07:25 AM

Originally posted by GeoJerry

I think you got it! I did have this setting set to On. I shot three bracketed images. I turned it off and shot three more. The latter three RAW images seem much truer to the JPEGs I see in the LCD. Thanks!

Sorry if you already know this (probably do!) -- highlight protection is just a one-stop underexposure, via cutting the ISO in half, and then boosting by one stop everything that's not a highlight. The camera knows to do this and that's why the RAW and JPEG look the same on the back LCD. However, computer imaging software might not know this (Aperture sure doesn't) so it thinks it's displaying, for example, an ISO 200 RAW image that was really shot at ISO 100. Because the camera already took care of adjusting the JPEG image, your computer displays it at the correct brightness..

GeoJerry · 06-06-2013, 03:27 PM

Originally posted by IchabodCrane

Sorry if you already know this (probably do!) -- highlight protection is just a one-stop underexposure, via cutting the ISO in half, and then boosting by one stop everything that's not a highlight. The camera knows to do this and that's why the RAW and JPEG look the same on the back LCD. However, computer imaging software might not know this (Aperture sure doesn't) so it thinks it's displaying, for example, an ISO 200 RAW image that was really shot at ISO 100. Because the camera already took care of adjusting the JPEG image, your computer displays it at the correct brightness..

This was all news to me. It makes me wonder how many other little pitfalls and quirks like that are hidden within the K-5's brains. Thanks again!

IchabodCrane · 06-06-2013, 05:45 PM

Originally posted by GeoJerry

This was all news to me. It makes me wonder how many other little pitfalls and quirks like that are hidden within the K-5's brains. Thanks again!

I'll totally understand if you wish to withdraw your thanks when I now mention that I'm a big Blackhawks fan!

05-31-2013, 02:52 PM	#1
GeoJerry Veteran Member Join Date: Dec 2011 Location: Santa Barbara, CA Photos: Gallery Posts: 5,158	Underexposed DNG Files I've noticed when I shoot RAW that the resulting DNG image is usually 1-2 stops underexposed relative to the correctly exposed embedded jpeg. Is this normal, or am I doing something wrong?

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05-31-2013, 03:04 PM	#2
Na Horuk Veteran Member Join Date: Feb 2012 Location: Slovenia, probably Photos: Gallery \| Albums Posts: 11,186	Hm, do you have a custom filter turned on? The "jpeg style" or "digital filters" can affect perceived brightness. Especially if you have it set to "bright." If you want the jpegs to look as much like the raw as possible, set it to neutral or natural.

05-31-2013, 03:07 PM	#3
stormtech Veteran Member Join Date: Jan 2011 Location: In the boonies (NW Penna) Photos: Gallery \| Albums Posts: 5,744	I think it depends a lot on which editor you are using. I've found the same when I use Acdsee Pro 6 - the PEF is 1.5 - 2 stops underexposed compared to the embedded JPEG. When I open the same file in Lightroom 4.4 I don't see this change - at least not as dramatic. I have my jpeg settings to the default "Bright" mode - I am guessing that if I had the jpeg settings to all neutral the raw and jpeg would be more similar. Edit: Na Horuk was posting the same time as I was.

05-31-2013, 03:26 PM	#4
GeoJerry Veteran Member Join Date: Dec 2011 Location: Santa Barbara, CA Photos: Gallery Posts: 5,158 Original Poster	Originally posted by Na Horuk Hm, do you have a custom filter turned on? The "jpeg style" or "digital filters" can affect perceived brightness. Especially if you have it set to "bright." If you want the jpegs to look as much like the raw as possible, set it to neutral or natural. Digital filters is set to off (default for RAW shooting), but I don't see any menu item call "jpeg style." Is that unique to different cameras (I have a K-5)? Or are you referring to the control to the right of the OK button? I had that set on Vibrant with +2 high key. Maybe that was it? I'll try, thanks!

05-31-2013, 03:27 PM	#5
GeoJerry Veteran Member Join Date: Dec 2011 Location: Santa Barbara, CA Photos: Gallery Posts: 5,158 Original Poster	Originally posted by stormtech I think it depends a lot on which editor you are using. I've found the same when I use Acdsee Pro 6 - the PEF is 1.5 - 2 stops underexposed compared to the embedded JPEG. When I open the same file in Lightroom 4.4 I don't see this change - at least not as dramatic. I have my jpeg settings to the default "Bright" mode - I am guessing that if I had the jpeg settings to all neutral the raw and jpeg would be more similar. Edit: Na Horuk was posting the same time as I was. OK sounds like you're both on the same track. I use Aperture, but I can try importing a jpeg directly into Topaz as well. Thanks!

05-31-2013, 05:10 PM	#6
stormtech Veteran Member Join Date: Jan 2011 Location: In the boonies (NW Penna) Photos: Gallery \| Albums Posts: 5,744	Originally posted by GeoJerry Digital filters is set to off (default for RAW shooting), but I don't see any menu item call "jpeg style." Is that unique to different cameras (I have a K-5)? Or are you referring to the control to the right of the OK button? I had that set on Vibrant with +2 high key. Maybe that was it? I'll try, thanks! Yes - the button to the right of the OK button. The settings there, called the custom image function I think, controls the jpeg output for the camera. But, when you shoot raw, the camera has to provide a jpeg image for you to view on the LCD screen, and for preview in editors. This embedded jpeg is controlled by the custom image function. I am not sure about this part, but I think that some editors will read these settings when opening a raw file while others will not. Like I said, I am sure that Acdsee does not, but it seems like Lightroom might since I see a distinct difference when opening the same raw file in each editor.

05-31-2013, 05:53 PM	#7
dms Site Supporter Join Date: Aug 2011 Location: New York, NY Photos: Gallery Posts: 2,192	(1) Try playing with the jpg options--increase contrast, etc.--to get a version that is closer to blowing the highlights at similar exposure does in camera raw. There are posts on this. (2) And/or just bias the exposure by the number stops needed--e.g., get enough testing under controlled conditions so you know what to do. Unless strong reasons to counter--for wide DR subjects--you should be exposing to the right--just shy of blowing the highlights--or even just blowing them sometimes--to get maximum quality.

06-05-2013, 07:18 AM	#8
reeftool Pentaxian Join Date: Dec 2007 Location: Upstate New York Photos: Gallery \| Albums Posts: 9,555	I've noticed a big difference in the exposure appearance from the LCD on the camera when I get them uploaded which is most likely a brightness setting issue. My monitor brightness is turned down to get close to printer output while my camera LCD brightness level is pretty bright. I tend to trust the histogram rather than the screen. Most of your camera JPEG options won't show up on your RAW photos after you upload but I'm pretty certain they are in effect in regards to the image you see on the camera LCD.

06-05-2013, 07:24 PM	#9
IchabodCrane Veteran Member Join Date: Sep 2012 Photos: Gallery \| Albums Posts: 1,728	Originally posted by GeoJerry I've noticed when I shoot RAW that the resulting DNG image is usually 1-2 stops underexposed relative to the correctly exposed embedded jpeg. Is this normal, or am I doing something wrong? Do you have Highlight Protection turned on? This will automatically cause my RAW files to be exactly 1 stop underexposed (which is exactly what the camera is doing) while the software (Aperture), apparently, doesn't detect that it needs to adjust the brightness by one stop.

06-05-2013, 10:17 PM	#10
GeoJerry Veteran Member Join Date: Dec 2011 Location: Santa Barbara, CA Photos: Gallery Posts: 5,158 Original Poster	Originally posted by reeftool I've noticed a big difference in the exposure appearance from the LCD on the camera when I get them uploaded which is most likely a brightness setting issue. My monitor brightness is turned down to get close to printer output while my camera LCD brightness level is pretty bright. I tend to trust the histogram rather than the screen. Most of your camera JPEG options won't show up on your RAW photos after you upload but I'm pretty certain they are in effect in regards to the image you see on the camera LCD. Each RAW image has an associated JPEG image embedded within it. The JPEG is what you see on the LCD and, for a brief moment (in Aperture anyway), on the monitor when the image is first uploaded to your PC. I'm not having any issues with the JPEG images on the LCD or monitor, just with the RAW image which underexposed. I think you're right about the options not affecting the RAW image.

06-05-2013, 10:19 PM	#11
GeoJerry Veteran Member Join Date: Dec 2011 Location: Santa Barbara, CA Photos: Gallery Posts: 5,158 Original Poster	Originally posted by IchabodCrane Do you have Highlight Protection turned on? This will automatically cause my RAW files to be exactly 1 stop underexposed (which is exactly what the camera is doing) while the software (Aperture), apparently, doesn't detect that it needs to adjust the brightness by one stop. I think you got it! I did have this setting set to On. I shot three bracketed images. I turned it off and shot three more. The latter three RAW images seem much truer to the JPEGs I see in the LCD. Thanks!

06-05-2013, 11:00 PM	#12
stormtech Veteran Member Join Date: Jan 2011 Location: In the boonies (NW Penna) Photos: Gallery \| Albums Posts: 5,744	Originally posted by GeoJerry I think you got it! I did have this setting set to On. I shot three bracketed images. I turned it off and shot three more. The latter three RAW images seem much truer to the JPEGs I see in the LCD. Thanks! Good catch to IchabodCrane - I didn't think any of those settings affected raw - only jpeg. Good to know.

06-06-2013, 07:25 AM	#13
IchabodCrane Veteran Member Join Date: Sep 2012 Photos: Gallery \| Albums Posts: 1,728	Originally posted by GeoJerry I think you got it! I did have this setting set to On. I shot three bracketed images. I turned it off and shot three more. The latter three RAW images seem much truer to the JPEGs I see in the LCD. Thanks! Sorry if you already know this (probably do!) -- highlight protection is just a one-stop underexposure, via cutting the ISO in half, and then boosting by one stop everything that's not a highlight. The camera knows to do this and that's why the RAW and JPEG look the same on the back LCD. However, computer imaging software might not know this (Aperture sure doesn't) so it thinks it's displaying, for example, an ISO 200 RAW image that was really shot at ISO 100. Because the camera already took care of adjusting the JPEG image, your computer displays it at the correct brightness..

06-06-2013, 03:27 PM	#14
GeoJerry Veteran Member Join Date: Dec 2011 Location: Santa Barbara, CA Photos: Gallery Posts: 5,158 Original Poster	Originally posted by IchabodCrane Sorry if you already know this (probably do!) -- highlight protection is just a one-stop underexposure, via cutting the ISO in half, and then boosting by one stop everything that's not a highlight. The camera knows to do this and that's why the RAW and JPEG look the same on the back LCD. However, computer imaging software might not know this (Aperture sure doesn't) so it thinks it's displaying, for example, an ISO 200 RAW image that was really shot at ISO 100. Because the camera already took care of adjusting the JPEG image, your computer displays it at the correct brightness.. This was all news to me. It makes me wonder how many other little pitfalls and quirks like that are hidden within the K-5's brains. Thanks again!

06-06-2013, 05:45 PM	#15
IchabodCrane Veteran Member Join Date: Sep 2012 Photos: Gallery \| Albums Posts: 1,728	Originally posted by GeoJerry This was all news to me. It makes me wonder how many other little pitfalls and quirks like that are hidden within the K-5's brains. Thanks again! I'll totally understand if you wish to withdraw your thanks when I now mention that I'm a big Blackhawks fan!