Nikon D5100 or Sony A57

Looks fine to me. The meter has turn the white areas to 18% grey, which is as I would expect. Just add add 2/3 of a stop in LR or ACR, or meter with spot metering somewhere that isn't white or black.
 
Try taking a series of photos with manual settings. Taking a photo with auto doesn't really tell you much, as a sudden light change can throw an image out.
 
ElDude said:
Try taking a series of photos with manual settings. Taking a photo with auto doesn't really tell you much, as a sudden light change can throw an image out.
Click to expand...

I shot 400 photos in manual on Wednesday. Every one of them were underexposed.

I'll give things one last chance at Uttoxeter races this Wednesday. I do doubt my 'ability' but on this occasion there's no doubt in my mind that there's an issue with lens or camera.
 
fozzybear said:
I shot 400 photos in manual on Wednesday. Every one of them were underexposed.

I'll give things one last chance at Uttoxeter races this Wednesday. I do doubt my 'ability' but on this occasion there's no doubt in my mind that there's an issue with lens or camera.
Click to expand...

Did you use auto ISO? If so, you were not shooting manually.

If anyone here thinks there is an issue from the example posted, I suggest they look into how a camera's metering system(s) work, and how it decides what is the correct exposure.

Just a quick tip, you may want to start with what is 18% grey, and how this magical percentage affects metering.

Once you understand how a camera meters, you will then understand how to use it effectively.

Lastly I also recommend, that anyone who doesn't already understand exposure and how to adjust it manually, to read a book called 'Understanding Exposure', I hear it's a good resource.
 
D700 exposure test.
Look at the sheet of A4 paper in the background to judge exposure differences.
Brown tape may influence exposures slightly, but not enough to void this example.

Spot Metered off white paper with brown tape (needed for focusing).
Note the under exposure
RW2_8449.jpg


Spot Metered off black flashgun with brown tape (needed for focusing).
Note the over exposure
RW2_8448.jpg


Spot Metered off 18% grey card with brown tape (needed for focusing).
Note a somewhat correct exposure.
RW2_8450.jpg
 
So when would it actually be a good idea to use Matrix metering instead?

Well if you are metering off something black or white, and not a shade of grey.

Example, the below shot is Spot Metered.
Note the over exposure.
RW2_8451.jpg


Part ii, the below shot is Matrix Metered.
Note the much more accurate exposure. It's much closer than when spot metered.
RW2_8453.jpg
 
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Demon said:
The A57 is identical to the A65/A77 at high ISO..

X9lHJ.jpg


The only reason people think it looks better is the 24MP is effectively blowing up the noise when view 1:1..

Many have done tests on DPReview comparing the 16MP and 24MP variants of the NEX and SLT cameras and the differences are miniscule even at ISO 6400.. infact, in good light the 24MP will still resolve more detail up to quite reasonable ISO values.

The science of sensors backs this up, at high ISO, for the same generation of sensors, the 'image' noise is solely based on the sensor size, not the number of MPs..

Of course with a 24MP sensor you are looking at the image much closer, so it appears to be noisier, but displayed or printed at the same size, worse case you won't see any difference..

All I am saying is, don't fall into the trap of buying small MPs because your gut tells you more MPs = worse ISO performance.. in the most meaningful way, that is not the case.. you would be better making the decision based on the camera's other abilities..

Sony SLT's all have 1/3 stop disadvantage in the light given to the sensor, that is quite a small difference, but if you don't care for the many superb SLT features, and just want high ISO, then you want a non-SLT camera..
Click to expand...

theres not a lot in it - but if you look at the DR and Colour Sens charts the A57 edges the A77 in most cases
 
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