fetch - size of remote file is not known

[David Schulz]

Hello all,

Viewing a certain Url results in a dynamically generated .png graph  
being displayed in my Browser. I would like to fetch this Graph.png  
via Command-line, but  a simple

"fetch https://www.domain.com/grapher/chart.php? 
graphid=1&stime=yyyymmddhhmm&period=7200&from=0&width=-108"

wont do, and results in an Error as below:

"fetch https://www.domain.com/grapher/chart.php? 
graphid=1&stime=yyyymmddhhmm&period=7200&from=0&width=-108: size of  
remote file is not known"

Is there a way i can force fetch to get that Graph, even when it  
doesnt know the size beforehand, or do you have another simple idea  
(no extra ports if at all possible) to get that Graph from Command-line?

Thanks a lot and best regards,
David