Track Day Pics, whats the problem?

[goodap]

Hi Guys, could you please help me.


I have recently purchased a Nikon D80 and am really pleased with the camera. I took a few picture recently and have attached a couple here.

I have had these printed off at my local photobooth, and have noticed a common thing on alot of my pics from this track day, its seems I have an area around the edges of the cars that is purpleish in colour. I believe this could be a highlight problem. Could anyone tell me if this is correct, and what to do to correct the problem. At the moment the camera is set to the factory defaults. Thanks






Any help would be greatful.

Cheers

Paul

[Graham@Reading]

What's the lens? Standard kit one?

Looks like it could be chromatic aberration - no idea if that lens suffers from it by reputation or whether you just have a dodgy copy though.

[David_G]

yep looks like CA to me, seconded on the lens question.

althogh the EXIF looks like a zoom of some sort - some cheap zoom lenses can cause your shots to suffer from CA quite badly.

[David_G]

.

Edited by David_G on Thursday 9th November 16:28

[te51cle]

I always thought purple fringing was more of a problem in compact cameras rather than SLRs, but you were shooting contrasty subjects, and with a wide-open lens, and shooting into the sun, and with shiny surfaces in front of you so that was as good a way of provoking problems as any !

I suggest that next time you stop down the aperture a bit so that you are shooting at F6.7-F8 instead of F4.5-F5, and stand so that the sun is at least to some degree behind you instead of in front of you. A lens hood may also help.

[goodap]

Thanks for the guidence, The camera setting were default. The lens in question is Tamron 70-300 F4-5.6.

I have been browsing many forums and its seems the Nikon D80 as a tendancy to over expose, compared to the the previous Nikon model, to try and provide more punchy pics straight out of the camera. Most people dial in a -0.3 or -0.7 ev. Also it has been suggested I should have changed the white balance to sunnny. Any more thoughts. Thanks Paul

This is the exif data for both.

Camera make: NIKON CORPORATION
Camera model: NIKON D80
Date/Time: 2006:10:28 17:55:07
Resolution: 640 x 428
Flash used: No
Focal length: 200.0mm (35mm equivalent: 300mm)
Exposure time: 0.0010 s (1/1000)
Aperture: f/5.0
ISO equiv.: 200
Whitebalance: Auto
Metering Mode: matrix

Camera make: NIKON CORPORATION
Camera model: NIKON D80
Date/Time: 2006:10:28 18:29:56
Resolution: 640 x 428
Flash used: No
Focal length: 105.0mm (35mm equivalent: 157mm)
Exposure time: 0.0020 s (1/500)
Aperture: f/4.2
ISO equiv.: 360
Whitebalance: Auto
Metering Mode: matrix

[_dobbo_]

The white balance looks fine in those and I don't think they are over-exposed either, other than maybe the bonnet on the first scoobydoo.

If it is chromatic aberration then as far as I am aware there is nothing you can change in the camera to avoid it.

[te51cle]

As dobbo says the white balance looks OK. Switching from matrix to centre-weighted metering would help get the exposure right for the cars and stop the camera from trying to compensate for the highlights and shadows in the backgound. Try that and getting the sun behind you and see how you go from there.

It won't affect the images but is the date and time set right ? I think it would be very dark at half past six on a late October day !

A bit of work in photoshop can get rid of some of the worst purple bits but it still doesn't quite look right. Image enlarged so the halos show up more:

[LongQ]

goodap said:

Date/Time: 2006:10:28 17:55:07
Resolution: 640 x 428

Date/Time: 2006:10:28 18:29:56
Resolution: 640 x 428

Apart from checking the clock setting ....

A res of 640 x 428 seems a little less than the camera ought to be capable of, unless Nikons use a different scale of measurement.

Are you sure that is right? Not much quality to be had at that level but a decent size memory card should last a lifetime ...


Or is that the Exif from the modified file posted here rather than the original?

Edited by LongQ on Friday 10th November 20:52

[David_G]

I think the answer is in the Tamron

[goodap]

Thanks for the replys guys, yes exif data is the reduced image size Actual shot was 3872x2592. Will try the centre metering. Just been reading the Nikon Forum on www.dpreview.com, and they are trying to get a petition going about the poor matrix metering results on the D80. They want Nikon to rectify the issue in a firmware update.

As for the lens I have some very reasonable pictures with it. I am thinking of going for a nikon 18-200vr or 70-300 vr in the future for these type of shots.

Thanks for all your help guys.

[monkeyhanger]

David_G said:

I think the answer is in the Tamron

I'm with Mr G. It's just a characteristic of the lens.