U of S | Mailing List Archive | alt-photo-process-l | Ply


Thanks Jeremy, that is what I thought. Ply is used as a term of thickness for mount board though rather than gsm or it’s imperial equivalent. Presumably this is because it’s made up of layers? I brought the question up as Eric mentioned Strathmore Artist Drawing paper 1 ply. I guess that as a measure of thickness/weight it’s meaningless and really a marketing term?






From: Jeremy Moore [mailto:jeremydmoore@gmail.com]
Sent: 15 January 2009 15:52
To: alt-photo-process-l@usask.ca
Subject: Re: Albumen paper and ply


No, because ply is the number of layers of paper and gsm is the weight of the paper. Each ply can be whatever weight you want, for instance, think of toilet paper: 1-ply is just one layer of toilet paper and 2-ply is two layers together. You may be thinking of the conversion between gsm and lb/sq.in.: 1 lb/sq.in. is about 704 kg/sq.meter and therefore 80 pound is roughly equivalent to 216.5 gsm.


On Thu, Jan 15, 2009 at 9:39 AM, John Brewer <john@johnbrewerphotography.com> wrote:

Thank-you Eric.


Is there a direct conversion from 'ply' to gsm?