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Old Aug 15, 2009, 11:56 AM   #1
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Default D40 Auto Mode problem?

I just bought a demo D40 from Cameta recently and everything seems to work great...except the following. For some reason, even in good outdoor lighting conditions, the D40 always severely underexposes in Auto mode. I know that I won't be using auto mode all the time, and I'm using the other modes as well. But sometimes I"d like to just be able to not have to fiddle around with any settings and go with the automatic settings (because I heard that the D40 was pretty good at taking photos in auto mode).

Is there any way I can remedy this? Or should I return it to Cameta/ask for a repair?
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Old Aug 15, 2009, 1:31 PM   #2
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I'd suggest posting a downsized sample of what you're talking about.

There are any number of reasons a camera will expose a certain way. For example, if you have a scene with a lot of dynamic range (greater range of bright to dark), a camera will usually lean towards proper exposure of your focus point using Matrix (i.e., multi-segment) metering, and some cameras will lean towards protecting the highlights instead. IOW, there may not be anything wrong with it.

When I use Windows, I use the free Irfanview for downsizing images (but, most image editors can resize if you're using something else).

With this software, after you open an image, select "Image>Resize/Resample" and make the width around 640 to 800 pixels wide for posting. Leave the Preserve Aspect Ratio box checked. After you click OK, use the "File>Save As" menu choice, select jpeg as the file type, and give it a new filename. I'd set the Quality slider you see come up at around 80% to keep the file size within limits. Leave the retain EXIF box checked (so members can see the camera settings you used), and attach the photo to a post here.

Then, members can look at the photo and give you some tips on what you can change for better results in the same conditions (and see what you mean by underexposure and if it appears to be normal for the shot you were taking).
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Old Aug 15, 2009, 2:11 PM   #3
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Sorry, I should've posted a sample pic/exif data before.

Here's a good example..it's a sunny day in Florida right now, or at least when I took this picture. On Auto mode it would give me this:



File name: DSC_0025.JPG
File size: 1972433 bytes (3008x2000, 2.6bpp, 9x)
EXIF Summary: 1/400s f/10.0 ISO200 18mm (35mm eq:27mm)

Camera-Specific Properties:

Equipment Make: NIKON CORPORATION
Camera Model: NIKON D40
Camera Software: Ver.1.11
Maximum Lens Aperture: f/3.5
Sensing Method: One-Chip Color Area
Color Filter Array Pattern: 836
Focal Length (35mm Equiv): 27 mm

Image-Specific Properties:

Image Orientation: Top, Left-Hand
Horizontal Resolution: 300 dpi
Vertical Resolution: 300 dpi
Image Created: 2009:08:15 13:32:59
Exposure Time: 1/400 sec
F-Number: f/10.0
Exposure Program: Not Defined
ISO Speed Rating: 200
Exposure Bias: 0 EV
Metering Mode: Pattern
Light Source: Unknown
Flash: No Flash
Focal Length: 18.00 mm
Color Space Information: sRGB
Image Width: 3008
Image Height: 2000
Rendering: Normal
Exposure Mode: Auto
Scene Capture Type: Standard
Gain Control: None
Contrast: Normal
Sharpness: Normal
Subject Distance Range: Unknown
ISO Speed Used: 200
Color Mode: COLOR
Image Quality: FINE
White Balance: AUTO
Image Sharpening: AUTO
Focus Mode: AF-A
Flash Setting: NORMAL
Flash Compensation: 0.0 EV
ISO Speed Requested: 200
Tone Compensation: AUTO
Lens Type: Nikon D Series
Lens Range: 18.0 - 55.0 mm; f/3.5 - f/5.6
Auto Focus: Closest Subject, Right Selected, Unknown Focused
Shooting/Bracketing Mode: Single Frame/Off
Color Mode: Landscape sRGB
Lighting Type: NATURAL
Noise Reduction: OFF
Camera Actuations: 2696
Saturation 2: AUTO
Digital Vari-Program: AUTO

Other Properties:

Resolution Unit: i
Chrominance Comp Positioning: Co-Sited
Exif IFD Pointer: 216
Compression Scheme: JPEG Compression (Thumbnail)
Horizontal Resolution: 300 dpi
Vertical Resolution: 300 dpi
Resolution Unit: i
Offset to JPEG SOI: 29508
Bytes of JPEG Data: 9285
Chrominance Comp Positioning: Co-Sited
Exif Version: 2.21
Image Generated: 2009:08:15 13:32:59
Image Digitized: 2009:08:15 13:32:59
Meaning of Each Comp: Unknown
Image Compression Mode: 4
Comment:
DateTime Second Fraction: 60
DateTimeOriginal Second Fraction: 60
DateTimeDigitized Second Fraction: 60
File Source: Other
Scene Type: Unknown
White Balance: Auto
Digital Zoom Ratio: 1
Saturation: Normal
Nikon Note Version: 2.10
Auto Flash Mode:
Flash Used: No
Image Optimization:

Am I horribly wrong to expect a better picture from Auto Mode? I know that I'll use the other modes later when I become more in tune with how to use the settings, but I think I deserve better pics than that when I'm in auto mode...unless I'm wrong, haha.

Thanks again.
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Old Aug 15, 2009, 2:19 PM   #4
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That looks normal to my eyes for an image with that much sky in the photo (which is going to be *much* brighter than the foilage at the lower part of the frame).

The camera was probably focusing on the sky, and the focus point is usually weighted more when using matrix metering. If you had tilted the camera down where your were focusing on the foilage instead, your exposure would have probably been much brighter.
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Old Aug 15, 2009, 2:46 PM   #5
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Here's one more:

File name: DSC_0044.JPG
File size: 1745460 bytes (3008x2000, 2.3bpp, 10x)
EXIF Summary: 1/320s f/9.0 ISO200 18mm (35mm eq:27mm)

Camera-Specific Properties:

Equipment Make: NIKON CORPORATION
Camera Model: NIKON D40
Camera Software: Ver.1.11
Maximum Lens Aperture: f/3.5
Sensing Method: One-Chip Color Area
Color Filter Array Pattern: 836
Focal Length (35mm Equiv): 27 mm

Image-Specific Properties:

Image Orientation: Top, Left-Hand
Horizontal Resolution: 300 dpi
Vertical Resolution: 300 dpi
Image Created: 2009:08:15 15:05:48
Exposure Time: 1/320 sec
F-Number: f/9.0
Exposure Program: Not Defined
ISO Speed Rating: 200
Exposure Bias: 0 EV
Metering Mode: Pattern
Light Source: Unknown
Flash: No Flash
Focal Length: 18.00 mm
Color Space Information: sRGB
Image Width: 3008
Image Height: 2000
Rendering: Normal
Exposure Mode: Auto
Scene Capture Type: Standard
Gain Control: None
Contrast: Normal
Sharpness: Normal
Subject Distance Range: Unknown
ISO Speed Used: 200
Color Mode: COLOR
Image Quality: FINE
White Balance: AUTO
Image Sharpening: AUTO
Focus Mode: AF-A
Flash Setting: NORMAL
Flash Compensation: 0.0 EV
ISO Speed Requested: 200
Tone Compensation: AUTO
Lens Type: Nikon D Series
Lens Range: 18.0 - 55.0 mm; f/3.5 - f/5.6
Auto Focus: Closest Subject, Center Selected, Top Focused
Shooting/Bracketing Mode: Single Frame/Off
Color Mode: Landscape sRGB
Lighting Type: NATURAL
Noise Reduction: OFF
Camera Actuations: 2725
Saturation 2: AUTO
Digital Vari-Program: AUTO

Other Properties:

Resolution Unit: i
Chrominance Comp Positioning: Co-Sited
Exif IFD Pointer: 216
Compression Scheme: JPEG Compression (Thumbnail)
Horizontal Resolution: 300 dpi
Vertical Resolution: 300 dpi
Resolution Unit: i
Offset to JPEG SOI: 28604
Bytes of JPEG Data: 10055
Chrominance Comp Positioning: Co-Sited
Exif Version: 2.21
Image Generated: 2009:08:15 15:05:48
Image Digitized: 2009:08:15 15:05:48
Meaning of Each Comp: Unknown
Image Compression Mode: 4
Comment:
DateTime Second Fraction: 80
DateTimeOriginal Second Fraction: 80
DateTimeDigitized Second Fraction: 80
File Source: Other
Scene Type: Unknown
White Balance: Auto
Digital Zoom Ratio: 1
Saturation: Normal
Nikon Note Version: 2.10
Auto Flash Mode:
Flash Used: No
Image Optimization:


Sorry for being so stubborn...I'm still just failing to see how my point and shoot SD600 can outperform a D40 in auto mode.
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Old Aug 15, 2009, 3:03 PM   #6
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The Point and Shoot model probably doesn't care if it's blowing highlights, and probably isn't giving as much weight to your focus point for exposure purposes. ;-)

If you want to use Auto models, I'd use P (Programmed Auto) instead. That way, if you know an image is going to be underexposed because your focus point is on a brighter area, you can use a +EV Setting to get a brighter exposure compared to the way the camera metered the scene. Or, if you have the opposite issue (overall exposure too bright because your focus point was on a darker subject), you could use a -EV setting to get a darker exposure than the camera metered.

You could also change metering mode to something else (for example, Center Weighted which is probably more consistent, without taking focus point into consideration) and/or set your camera so that you've got Automatic Exposure Lock with a half press of the shutter button (focusing on something neutral in brightness, half pressing the shutter to lock both focus and exposure, reframing and pressing it the rest of the way down to take the photo).

Any camera's metering tends to take some getting used to, and a dSLR model is usually going to give you more precise control. With a typical point and shoot model, you'll tend to get a photo where the majority of the frame may be properly exposed (but, it may not care if you have blown highlights, or if the area you're focusing on gets more weight for exposure purposes).

Since you are probably focusing on a bright sky in those two examples, I don't see anything abnormal about your camera's behavior.
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Old Aug 15, 2009, 3:12 PM   #7
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Is the exposure fine if you're not pointing the camera towards the sky (for an evenly lit scene versus back lit subjects)? If so, then you're probably just seeing normal metering behavior from your camera.
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Old Aug 16, 2009, 10:15 AM   #8
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The pictures look too dark for the settings reported in the EXIF data. The first is reported as 1/3 stop open from the classic "Sunny 16" rule for a sunny day. The second is right on the Sunny 16 rule for Hazy Bright, reasonable for shooting through the screened in Lanai. I don't think there is any issue with the meter determining the correct exposure.

If the camera actually used the settings reported, I would expect a much brighter image. I suspect a shutter problem (firing at a much higher speed than the meter specified) or an aperture stop down problem (body closing the lens all the way instead of trapping the aperture lever at the correct position for the desired aperture). Either would indicate the need for shop service. Hopefully the OP's "demo" model has some sort of warranty.
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Old Aug 16, 2009, 11:35 AM   #9
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You've got too many variables involved to go by minor exposure differences in the EXIF (was the sun partially obscured by clouds, etc.).

Also, almost any camera is going to expose darker if you point it towards the sky, especially with white clouds in the image.

If you're shooting a darker subject, most cameras will tend to expose brighter than desired (for example, turning a black suit more towards gray). If you're shooting lighter subject, most cameras will tend to expose darker than desired.

If the only time the camera is producing those types of images is when you're pointing it towards the sky with white clouds in it, then I doubt there is anything wrong with it.

For more informed advise, the OP needs to respond to this question:

Quote:
Originally Posted by JimC View Post
Is the exposure fine if you're not pointing the camera towards the sky (for an evenly lit scene versus back lit subjects)? If so, then you're probably just seeing normal metering behavior from your camera.
If the answer is no (still seeing exposure problems when not pointing it towards the sky), then some examples showing the issue would help to determine if there is anything wrong with it or not.
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Old Aug 20, 2009, 3:26 AM   #10
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Take the same photo but changing modes so we can see the difference.

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