Photo Exposure Help

[RHVette]

I tried to take some photos of the full moon last night since it was so clear. Through the camera, I could see all the details on the surface, but when I took the pictures, all I got was a white ball. I got great definition out of the clouds, though. Anybody have a clue what I did wrong? I think maybe the shutter speed was too slow because I used the suggested settings and it must have based that on the sky, which overexposed the moon.

 

[Miles]

Yeah, it looks like the moon shots are overexposed. Try fiddling with the full manual settings to find something that works, maybe practice on a non-full moon so you'll be ready to go for the next one. Good luck!

 

[RHVette]

Which aspect do you think was off, though? The f-stop and aperture were run pretty much throughout their entire range with negligible effect, so I'm guessing it was either the shutter speed or the film speed (ISO400) that was off.

 

[MrDentini]

You did nothing wrong, it's the sensor that has a "dynamic range" way lower than your eyes.
It can't register such a difference in luminosity, from very dark to very light. Usually a normal sensor can record no more than 7 stops.

In situations like that you have to find a compromise: underexpose to have detail in the moon (making the clouds too dark), or overexpose to have detail in the clouds (burning the moon). What the "auto" setting does is find a median value that is neither fish nor flesh.

Or... you could take multiple shots (using a tripod) and then merge the images in postproduction, using the good part of each image. In this case, remember to vary the exposure not using the aperture (since it would vary the depth of field), but the shutter speed.

Or... if it was the entire sky to be too light, you could reduce the dynamic range by using a filter.
Hope it helps.

 

[Blix]

The moon is illuminated by the sun, so you need a daylight exposure. Also, it moves rather fast, so you need a fairly quick shutter speed to avoid blur.

 

[Edcculus]

I would do a little experimenting. Set your camera ISO to around 400 and put into manual mode.

Start with an aperture of f/16 and a shutter speed of 1/250. Then bracket your shots by taking a picture at 1/125 and 1/500. You could even try really underexposing by taking the shutter speed to 1/1000. Obviously you can do the same thing by adjusting the aperture, but since you are shooting a far away object, and you have already seen your camera wants to over expose the moon its probably best to keep the aperture as small as possible.

It also wouldn't hurt to use a tripod.

 

[Oblique Human]

I shot the moon last night too. Check out the EXIF info for the settings.

Filename - P1050038_crop.jpg
Make - Panasonic
Model - DMC-FZ28
Orientation - Top left
XResolution - 180
YResolution - 180
ResolutionUnit - Inch
Software - Ver.1.0
DateTime - 2012:06:04 23:27:25
YCbCrPositioning - Co-Sited
ExifOffset - 636
ExposureTime - 1/320 seconds
FNumber - 4.40
ExposureProgram - Aperture priority
ISOSpeedRatings - 100
ExifVersion - 0221
DateTimeOriginal - 2012:06:04 23:27:25
DateTimeDigitized - 2012:06:04 23:27:25
ComponentsConfiguration - YCbCr
CompressedBitsPerPixel - 4 (bits/pixel)
ExposureBiasValue - -0.33
MaxApertureValue - F 2.83
MeteringMode - Spot
LightSource - Auto
Flash - Flash not fired, compulsory flash mode
FocalLength - 86.40 mm
FlashPixVersion - 0100
ColorSpace - sRGB
ExifImageWidth - 1254
ExifImageHeight - 944
InteroperabilityOffset - 10242
SensingMethod - One-chip color area sensor
FileSource - DSC - Digital still camera
SceneType - A directly photographed image
CustomRendered - Custom process
ExposureMode - Auto
White Balance - Auto
DigitalZoomRatio - 0.00 x
FocalLengthIn35mmFilm - 866 mm
SceneCaptureType - Standard
GainControl - None
Contrast - Normal
Saturation - Normal
Sharpness - Hard

Maker Note (Vendor): - 
Image Quality - High
Focus Mode - Auto
AF Mode - 5 area
Color Mode - Normal
Faces Detected - 0

 

[jamesnj]

The easiest fix would be to try spot or center-weighted metering instead of matrix (or evaluative, depending on your camera). The matrix metering used by default on most cameras looks at the whole scene to figure out the exposure, and can get it wrong when the scene is very high contrast. By using spot metering, you would meter just for the moon. center-weighted is in between the other two. It looks at the whole scene, but puts a higher weighting on the center.

There's an internet TV show, dtowntv (www.dtowntv.com) that just ran a segment about the metering modes last week or the week before, complete with some examples.

You also have to remember that in an automatic mode (including aperture priority or shutter priority), if you increase the shutter speed, the camera will open the aperture more and vice versa, so the exposure stays the same. To change the exposure, you need to use exposure compensation, manual mode, or in some cases change the metering mode.

James

 

[scottish steve]

I took a very similar shot the other night and was going for mother of pearl cloud look. Using a 80mm equiv lens didn't give me much moon to work with. I also got this strange phenomemon, which I assume is effectively time-lapsed micro-meteor impacts

 

[Blix]

I took a very similar shot the other night and was going for mother of pearl cloud look. Using a 80mm equiv lens didn't give me much moon to work with. I also got this strange phenomemon, which I assume is effectively time-lapsed micro-meteor impacts

Nope, it's reflections on your front lens. Rule number one for shooting into bright objects in high contrast: Remove any filters.
And keep the front lens 100% clean.

 

[scottish steve]

not the lens flare. I mean these

 

[Blix]

not the lens flare. I mean these

Uh oh, those are clearly an alien invasion!

 

[scottish steve]

That's what I called this pic.
I'll have to try Oblique's setting when I get a clear night. I'd never have thought of using such a short exposure, but it's all a learning curve isn't it?

 

[Oblique Human]

not the lens flare. I mean these

I knew I wasn't hallucinating, those dirty cockroach-eyed kidney-grabbing freaks.

 

[scottish steve]

One advantage of high humidity and pollution?
I have several times tried to imagine an appropriate sound effect for that impact. I think I'm a geek!