Olympus-OM
[Top] [All Lists]

[OM] Re: Digital vs film resolution

Subject: [OM] Re: Digital vs film resolution
From: Andrew Fildes <afildes@xxxxxxxxxxxxx>
Date: Fri, 10 Mar 2006 07:47:06 +1100
Go take a look at a 'screened' B&W half tone reproduction in a  
printed publication. That is 'binary'. However there are two other  
variables - the number of dpi and the size of the dot. It's binary  
with yes-no-YES-NO-maybe-probably-definitely. :)
The critical factor is the dpi - equivalent to pixel density if you  
like. A coarse screen at say 60dpi in a tabloid newspaper looks crude  
but compare it with a 300dpi image on coated paper in a top grade  
photo book or company prospectus where the smooth tone and resolution  
makes the screen near invisible.
Not only is film layered but the grain size and thickness is variable  
as well, in response to exposure and development. No pixel array can  
really match that as while response is variable, size and position is  
not. This may also account for the difference in 'feel' in the final  
image, the indefinable sense that there is something a bit different  
happening.
AndrewF


On 10/03/2006, at 12:36 AM, james king wrote:

> I am having real problems with this argument about sensor spacing vs
> grain size.
> firstly since digital sensors see in black and white and require a
> coloured filter to see in colour you need 3 sensors to get colour not
> one. Secondly you need an antialias filter. thirdly there is space
> between each sensor which can therefore record nothing at all.
> *assuming* film grain is binary then you only need 8 grains to  
> simulate
> 256 combinations and 24 grains to get 24 bit rgb. However film is
> layered (unlike digital sensors) therefore you only need 8 grains in
> three layers ontop of each other to get 24 bit rgb whereas digital
> requires three sensors.
> my 2pence worth
> James



==============================================
List usage info:     http://www.zuikoholic.com
List nannies:        olympusadmin@xxxxxxxxxx
==============================================

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