In general copyright subsists in a photographic work for 50years after the death
of the creator.   If you do not need to reproduce the print for mounting in the
exhibition, you may publicly exhibit any original artistic work created before
1988 without permission of the copyright holder.  All photos created before 1949
are considered in the public domain, so you could reproduce those for an
exhibition.

I would refer you to the expert source on this issue:
Title	Demystifying Copyright: A Researcher's Guide to Copyright in Canadian
Libraries and Archives
Authors	Jean E. Dryden, Canadian Library Association
Contributor	Canadian Library Association
Publisher	Canadian Library Association, 2002
Original from	the University of Michigan
Digitized	28 Oct 2008
ISBN	0888022980, 9780888022981
Length	46 pages

Ralph Coram
Jazz Clubs Visual History Project/
Canadian Jazz Archives Network  (Toronto)
> ---------- Original Message ----------
> From: Vanessa Lio <[log in to unmask]>
> Date: July 13, 2017 at 2:49 PM
> 
> 
> Hi Everyone,
> 
> I was hoping you could help me out with a question. I have a group of three
> photos that are wanted for an exhibit display at the museum. The photographer
> died in 1983, the images were taken ca. 1950. We would like to use them for
> the exhibit. Would copyright, in your opinion affect the use of these photos
> for display? They are not being used for promotional material.
> 
> Thank you for all your help!
> 
> Vanessa Lio,  Archives Assistant
> Dufferin County Museum & Archives
> 936029 Airport Road
> Mulmur, Ontario   L9V 0L3
> Toll Free 877.941.7787,  x 4017
> New local number: 519-941-1114   x 4017
> www.DufferinMuseum.com<http://www.dufferinmuseum.com/>
> 
>  [2017 logo resized]
> 
>                 We make history...Local.
> 
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> www.dufferincounty.ca
> 
> ====================================

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