02GF74
|
 posted on 16/2/09 at 09:43 AM |
|
|
Ooooh loook!!! photo question
How did I manage to take this?
Was trying to get cat in a tree but pressed the shutter and moved camera unintentionally - came out quite nicely.
How come cat is in focus but the background isn't?
 
Rescued attachment DSC04362.JPG
|
|
|
|
|
Peteff
|
| posted on 16/2/09 at 10:51 AM |
|
|
Apparently the camera is cleverer than the photographer. 
yours, Pete
I went into the RSPCA office the other day. It was so small you could hardly swing a cat in there.
|
|
|
Bob C
|
| posted on 17/2/09 at 10:44 PM |
|
|
fill in flash happened
|
|
|
02GF74
|
| posted on 18/2/09 at 08:33 AM |
|
|
^^^ explain?
I sem to recall trying to take photo then decide against it and moving camera; at some stage I pressed the shutter.
I cannot work out why the cat is in focus, well, reasonably in focus, but the background to the left of the twee is not.
|
|
|
wilkingj
|
| posted on 18/2/09 at 09:21 AM |
|
|
Ah... You are all wrong.
The answer is much simpler and can be explained mathematically.
The Cats fur is Fuzzy as there is no real fixed surface. You are looking at the ends of the hairs and along their length. Thus there is multiple focii
(plural focus's??) at the same point. Hence its fuzzy or out of focus.
With the background being out of focus, (it will just be out of focus), and the Fuzzy cat (imagewise) being at the same distance the cat will appear
in focus.
So mathematically transposing this all you have two out of focus areas. When these come together where the cat is in the picture, two negatives give a
posative. Hence the Cat becomes into focus whilst surrounded by an out of focus background.
There I told you it was simple.
The effect you have produces is very good.
Well Done.
1. The point of a journey is not to arrive.
2. Never take life seriously. Nobody gets out alive anyway.
Best Regards
Geoff
http://www.v8viento.co.uk
|
|
|
Mr Whippy
|
| posted on 18/2/09 at 09:57 AM |
|
|
Here’s a nice picture of my sneaky dogs, taken on the mobile so that’s my excuse for the quality 
Typically their trying to get away with murder when we turn our backs and sleeping on the bed!
 
Fame is when your old car is plastered all over the internet
|
|
|
Liam
|
| posted on 18/2/09 at 12:40 PM |
|
|
What camera/settings?
It's almost certainly a shot done with the flash on slow sync mode. That combines long exposure with a burst of flash. The long exposure alows
the dark background to be exposed, and in your case with lots of motion blur, while the short burst of flash creates a sharp well exposed subject.
Liam
|
|
|
matt_claydon
|
| posted on 18/2/09 at 04:58 PM |
|
|
quote:
Originally posted by Liam
What camera/settings?
It's almost certainly a shot done with the flash on slow sync mode. That combines long exposure with a burst of flash. The long exposure alows
the dark background to be exposed, and in your case with lots of motion blur, while the short burst of flash creates a sharp well exposed subject.
Liam
What he said ^
|
|
|
MikeRJ
|
| posted on 18/2/09 at 08:02 PM |
|
|
quote:
Originally posted by Mr Whippy
Here’s a nice picture of my sneaky dogs,
Have they had surgery recently? It appears someone has attached elephants feet to them 
|
|
|
Hellfire
|
| posted on 18/2/09 at 08:46 PM |
|
|
quote:
Originally posted by matt_claydon
quote:
Originally posted by Liam
What camera/settings?
It's almost certainly a shot done with the flash on slow sync mode. That combines long exposure with a burst of flash. The long exposure alows
the dark background to be exposed, and in your case with lots of motion blur, while the short burst of flash creates a sharp well exposed subject.
Liam
What he said ^
Sorry Winkinj - but you're not quite right .... it's what he said ^^^^^^^^
|
|
|
Mr Whippy
|
| posted on 19/2/09 at 06:57 AM |
|
|
quote:
Originally posted by MikeRJ
quote:
Originally posted by Mr Whippy
Here’s a nice picture of my sneaky dogs,
Have they had surgery recently? It appears someone has attached elephants feet to them
their pawprints are the size of my palm! They don't tend to fall over much...
Fame is when your old car is plastered all over the internet
|
|
|
02GF74
|
| posted on 19/2/09 at 03:16 PM |
|
|
I think it was done with a flash; that info shold be encoded in the photo I'd have thought. The camer is a 5 mp sony compact, photo on vga
setting so nothing fancy.
I seem to remember pressing shutter thant thinking I'll abort pictyre hence hte reason for moving it - I expected to see pictyures of the ground
or something.
One theroy I had was that the CCD scanning had started at the top when the camera ws not moving so is in focus andthen wnet blurry when moved but I
don't think that is likekly - the time to scan has to be in order of microseconds.
I guess I need to go out and play with the camera to see if I can repeat this.
|
|
|
Liam
|
| posted on 22/2/09 at 11:48 AM |
|
|
The whole sensor is exposed and aquiring charge for the duration of the exposure, just like a piece of film would be - there's no starting at
the top and working down etc etc (except perhaps in the way the sensor data is read after the exposure).
It's definately a slow sync flash shot. If not specifically called that or selected by yourself, were you in something like a 'night
portrait' mode, for example, which would have done the same thing? A compact's full auto mode may even have chosen a slow sync flash in
that situation. Either way you've got a short burst of flash creating a sharp foreground - look how it's not just the cat at the top
that's sharp, but the whole trunk and the grass at the bottom close to the tree, i.e. all the stuff closest to the flash. The shutter has
stayed open after the flash (i.e. slow sync mode) helping to expose the dark background. You were probably moving the camera the whole time creating
the blur because even the flashed part isn't that sharp!
Go on - post the pic's metadata so we can see shutter speed etc etc etc.
Liam
[Edited on 22/2/09 by Liam]
|
|
|
