What's wrong with my photo? Please Help.

alexhcowley

alexhcowley

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Alex
Edit My Images
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Last Sunday, I went stalking Red Pandas at Chester Zoo. The camera did some very strange things with the exposure on quite a few of the shots.

I was using my trusty Canon 450D, with an EF-S 55-250mm zoom attached, single point auto-focus, apperture priority mode (apperture F7.1) and pattern metering. The lens focal length was the full 250mm.

For Photo one, the camera ramped the ISO up to 800 and chose a shutter speed of 1/125th of a second. The results are grotty to say the least.

For Photo two, it chose ISO 640 and a shutter speed of 1/250th of a second. The result is an exposure which is still far from perfect but much better than photo two.

The photos were taken about two seconds apart at 12:46 pm. The day was sunny and clear.

To me, it looks like the camera used spot metering on photo one although the EXIF data insists that both photos were taken with pattern metering.

I would welcome any insights as to what's happening here.

Photo-One.jpg


Photo-Two.jpg
 
Part of your problem maybe shutter speed:

When you're racked out at 250mm, the rule of thumb is that you should have a shutter speed of 1/250, unless you're on a tripod or have image stabilisation (IS). You're on a cropped sensor so it might be safer to multiply by 1.6 for your rule of thumb, e.g. 1/400. You can gain a bit more speed by opening up your aperture to wide open. I'd also be inclined to up your ISO. Your images don't look too noisy - even if they did, you can deal with noise, you can't deal with a shakey image. Try ISO 1600. If it is too noisey you can always go mono. (I assume you shoot in RAW).

Top Pic looks washed out:

Were you shooting through glass, perhaps you're shooting through a reflection of someone's white shirt. I wonder if you were shooting into the light, perhaps light is landing on your front element and washing out. If you stop down (set EC to -1), it should help saturate the colours a little (and it speeds up your shutter speed a bit too). You could have had a lens hood or had a friend cast a shadow onto your front element. Cheap UV filters can sometimes cause problems too. Another possibility for the top pic being over exposed might be if the day had fast changing light (sun going in and out of cloud etc) and maybe you half-pressed the shutter release and held it there for long enough that the light changed. Try to reduce the time between the half-press and shutter release.

...otherwise these are nice shots. If you shot in RAW and have Lightroom (or similar) you should stand a chance of recovering the highlights and restoring some saturation.

Good luck

Hope some of these ideas are of some help.

Steve
 
Very strong sunlight from the right is blowing out the whites.

and also a little camera shake is going on there to.
#2 looks as though you have focused on the arse not the eyes.

Try going a "stop" (or even 2 stops) down on the compensation slide in the view finder
Its not that easy hand holding at 1/ 125th well I struggle anyway :D
Were you shooting through glass?
This can give a slightly hazy effect too.

However, on the 8th day God created photo-shop,so
all is not totally lost, and at least some detail can be pulled back

They are not brilliant as they are only small Jpegs, but with the full sized file you may have more luck
Shadow highlights tweaked, along with the contrast and USM


copy_Photo-One.jpg


copy_Photo-Two.jpg
 
There are two possibilities that I can see.
1. The lens diaphragm has become sticky. You can check this by setting aperture priority and taking a series of shots of the same scene at various apertures starting with the lens wide open. Focal length is immaterial. If the wide open one is ok and exposure gets steadily worse as you stop down then get the lens checked out.
2. The more likely one is that your metering has strong centre weighting and has picked up the majority of the exposure from the black centre of the panda's fur. In trying to expose for an average grey-scale for this area it has over-exposed the remaining areas. This is an unfortunate fact of life - exposure-meters aren't perfect so it'll happen from time to time. Check your images on the screen regularly so you can shoot again if they're bad. Spot metering on the panda's face would have given better results in this instance.
 
Thanks for the help, guys, your comments are most useful. I think Cobra has it right, strong sunlight from the right upset the 450D's cheap and cheerful metering system.

Incidentally, the photos were taken using a monopod, a lens hood and were not taken through glass. (One of the good things about being a red panda stalker is that Zoos tend not to hide the animals behind thick wire fences, glass or wide moats. The main downside is that the little so and sos have a nasty habit of hiding in trees when the punters are around. They can be most anti-social that way.)
 
On a lot of cameras there is a choice in the menu to choose 1/2 and 1/3 ISO settings which is how you get to 640 :)
 
Don't agree with the camera shake, while they may not be the sharpest pics looking at the whiskers the camera must have been still.
I think the exposure on the black fur looks good and would guess that's the cause of the problem.
 
Ye agree with eccles, it looks like the metering is off. The black fur and what would looks like a predominantly dark background have caused the camera to try to over expose in the hope of getting it to an average grey so it's gone with a longer shutter speed than you'd want handholding at that focal length. As you can see there are blown highlights in the corner and, to me, in the face. The reason for the first looking stranger than the second is likely due to motion blur at the 1/125 shutter speed v 1/250 on the second (which is closer to the 1/400+ you're looking for). Can't quite explain why the metering changed between the two though.

I would've tried -1EC to see if that got you the required shutter speed, and check the histogram to see if the exposure is right. It's important to keep a close eye on the shutter speed when using these long focal lengths, even if that means more ISO (though I might try wider aperture in preference).
 
a need for spot metering and some familiarity with manual settings
 
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