[stepheno]

I can only ask the question by showing two photographs in which both are taken with a 30D with the 24-105. Why is the IQ in photo 2 so inferior to Photo 1?

Photo 1 - 1/13 at f4.0 on ISO 1600, hand-held




Photo 2 - 30 secs at f5.0 on ISO100, camera on a stable surface and used remote shutter cable.

[Steve]

The second shot is showing the effects of it being out of focus rather than it moving. If I had to place my money on one thing, that would be it. Are you absolutely sure it was focused correctly, maybe you had not locked focus and when you pressed the shutter release, the lens and camera hunted and couldn't get a good focus lock?

If thats the case though then depending on the camera mode and your custom settings it should have prevented the picture from being taken

Was it shot in manual or auto focus?

[silkstone]

^^^^ Agreed. There's no sign of motion blur and it looks simply as if the focusing was wrong, which is a little odd if it was in AF mode.

Rather OT, but I'm interested that you used spot metering for both shots.

[stepheno]

Originally Posted by Steve

The second shot is showing the effects of it being out of focus rather than it moving.

That, I think answers my question. It was a manual shot and maybe the remote hasn't locked focus. Another point you've just reminded me of ........the next day I noticed my diopter was out. Could it be I've focussed to allow for that which in truth produces an out-if-focus-image.

Thanks for your help, Steve.

[Steve]

That could well have solved the riddle. If you have the focus confirmation lights active (in the viewfinder), even using manual focus you should be able to tell when it's spot on and the diopter being 'wrong' will then have no effect on the final image. Obviously you need to have confidence in both the lens and the camera's AF accuracy though.

Also for night shots I would have increased the F stop and increased the shutter open time accordingly. If the time then becomes excessive, remember that for each stop that you under expose, you can claim back precious seconds and its much quicker to recover 1 stop of underexposure during post processing. If you are shooting RAW you'll hardly notice the difference in the final result

[Markulous]

Originally Posted by stepheno

Photo 2 - 30 secs at f5.0 on ISO100, camera on a stable surface and used remote shutter cable.

Define "stable"! I've found that tripoded I can get very small vibrations that show as blur

Originally Posted by silkstone

....which is a little odd if it was in AF mode.

Asking rather a lot of AF! When it gets to dusk I find I switch to MF (prefer MF anyway, TBH)

[stepheno]

Originally Posted by silkstone

Rather OT, but I'm interested that you used spot metering for both shots.

That will have been a senile moment Sikstone - I often use spot during the day in bright sunlight and forget

[stepheno]

Originally Posted by Markulous

Define "stable"! )

Stable was the camera sitting on a concrete block

[Dave]

Originally Posted by stepheno

Stable was the camera sitting on a concrete block

Unless it was bolted to the block, it still ain't stable <says the biggest culprit with no tripod >

[silkstone]

Ah, but was it a stable block?

And did you remove the hay first?

:

[Dave]

Neigh

[Boofers]

wayout in right field maybe, but it looks like your focus "manual or auto" lit-up the light on the right middle, like real close to you. And left the picture part out. Do like your top picture and to this day have never shot a picture above ISO800. Must give it try, will follow your lead here for the ISO anyway.