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pjs2
01-09-2010, 5:44pm
Took this pic at 5 ish in the morning .Cant really say how long exposure it was ( I think about 10 sec). Is this effect from to short exposure time?


57923

GlennSan
01-09-2010, 5:56pm
Your EXIF data says:

Exposure Time (1 / Shutter Speed) {0x829A} 10/1 second ===> 10 second
Lens F-Number / F-Stop {0x829D} 29/1 ===> ƒ/29
ISO Speed Ratings {0x8827} 12800

So, there are two things I see here.
1. The multiple rays emanating from the lights are due to the very small aperture you've used. (F29).
2. The multi-coloured speckles are noise resulting from insufficient light during the exposure and possibly camera-generated noise as well. So yes, Too short an exposure seems to be a contributing factor. Conversely, you could have used a larger aperture, like F8. The veryhigh ISO may have contributed as well.

Hope this helps a little.

dt86vyss
01-09-2010, 6:00pm
looks to me like a really high ISO?? it depends on how good the light was at the time, but if it was dark (near no light) then i would suggest 10 seconds is too short. Perhaps 20 - 25 seconds at F11 and ISO100, with a little additional post processing in Lightroom (or the like) would have produced a much better result here. - give it a try and let us see the outcome...

ricktas
01-09-2010, 7:17pm
ISO 12800 is the major cause here

BradGC
04-09-2010, 7:22am
I'm still new to photography and have made this mistake in the past so just passing on a mistake that you might have made... the higher the aperture number, the smaller the hole, so basically you want to open it up as much as you can for the lens that you are using, so maybe like 3.5 - 6.

possibly get back to basics and use auto shot, or even see what settings an auto shot would choose for you and then replicate that on manual or a priority setting.

ZedEx
11-09-2010, 7:39am
a lot of lenses will still yield that star shape highlight coming from those two light sources at f16 and to a lesser extend f11, if that was the look you were after? This means you could use a lower ISO. Generally, exposures of 10 seconds shouldn't give undue noise, however 12800 is a shocking ISO setting to use and should only ever really be used for daytime shots when you need a really fast shutter speed and have absolutely no other option. Used in dim situations like this the noise will be painfully visible. I'd try ISO 400 or under (100 ideally) and a longer exposure, if you find yourself in a similar situation next time