Olympus-OM
[Top] [All Lists]

Re: [OM] [OT] Why?

Subject: Re: [OM] [OT] Why?
From: Chuck Norcutt <chucknorcutt@xxxxxxxxxxxxxxxx>
Date: Tue, 17 Aug 2010 19:23:28 -0400
Probably taken with a kit lens that was wide open at f/4.9 at 78mm.  It 
appears to me that the shot was taken in heavy shade.  If the ISO is 
overspecified it's probably only by one stop.  The shot was taken at 
1/250.  At ISO 800 it could have been at 1/125 which is about as low as 
you'd want to go on a small sensor camera at 78mm.

Do you recall the old 35mm rule of thumb that to counteract camera shake 
you shouldn't use a shutter speed slower than the reciprocal of the 
focal length?  For small sensor cameras you need to modify that rule by 
the crop factor.  For Canon that's 1.6 which would yield 1/78x1.6 = 
1/124.8.  Can't get much closer to 1/125 than that.  And, of course, 
that's the minimum.  To guarantee a sharp image the photog should use a 
faster speed... like 1/250 which is what was done here.  Of course, the 
lens might have had IS... but probably not.

It's a pretty small image so it's hard to tell but it does look pretty 
good for ISO 1600 on an APS-C size sensor.

Chuck Norcutt


Willie Wonka wrote:
> Why would one choose to use ISO 1600 for this particular shot:
> 
> http://www.bikeexif.com/honda-cb750-2
> 
> Best
> 
> Boris
> 
> 
> 
>       
-- 
_________________________________________________________________
Options: http://lists.thomasclausen.net/mailman/listinfo/olympus
Archives: http://lists.thomasclausen.net/mailman/private/olympus/
Themed Olympus Photo Exhibition: http://www.tope.nl/

<Prev in Thread] Current Thread [Next in Thread>
Sponsored by Tako
Impressum | Datenschutz