The precise language and world of mathematics can be used to investigate this question.
A few formulas of interest.
CURVATURE
C = R(1 - cos[s/(2R)]) - angle measured in radians
R = 6378,164 km
s = distance
VISUAL OBSTACLE
BD = (R + h)/{RAD[2Rh + h^2](sin s/R)(1/R) + cos s/R} - RRAD = SQUARE ROOT OF THE EXPRESSION IN THE [ ] PARENTHESES
TERRESTRIAL REFRACTION
http://ireland.iol.ie/~geniet/eng/refract.htm (Calculating the effects of refraction on apparent altitude section)
LOOMING (THERMAL INVERSION)
http://mintaka.sdsu.edu/GF/explain/atmos_refr/altitudes.htmlLet us apply this mass of knowledge to a famous photograph taken by Mrs. Kerry Ann Lecky Hepburn in Grimsby.
The RE called her some years ago, they were informed that the elevation was 170 meters above sea level.
Since lake Ontario is itself some 75-80 meters above sea level, the following photograph was taken from 90 meters in height.
We will add 20 MORE METERS, to reach an elevation of 110 meters (highest point in Beamer Falls Conservation Area).
GRIMSBY - OSHAWA 97 KILOMETERS


VISUAL OBSTACLE: 278 METERS
Tallest building in Oshawa: Summit Place, 64.5 meters
Elevation of Oshawa above sea level: 106 meters
Substracting 80 meters (elevation of lake Ontario itself) from 106 and adding 64.5 meters we get: 90.5 meters
Using the refraction formula we see immediately that nothing from Oshawa could be seen/observed from a 97 km distance.
Let us now use the LOOMING formula.
http://mintaka.sdsu.edu/GF/explain/atmos_refr/altitudes.htmlTHE PHOTOGRAPH WAS TAKEN ON JUNE 10, 2004
http://climate.weather.gc.ca/climateData/dailydata_e.html?timeframe=2&Prov=ONT&StationID=4996&dlyRange=1840-01-01%7C2014-7-22&Year=2004&Month=6&cmdB1=Go#OSHAWA: TEMP MAX 16.5 C - TEMP MIN 13.5 C
GRIMSBY: TEMP MAX 16.5 C - TEMP MIN 10 C
http://www.theweathernetwork.com/weather/historical-weather/caon0281We introduce the data:
EYE OBSERVER: 13.5 - 14.5 - 15.5 C (temperature)
HEIGHT 110 METERS
EYE TARGET: 13.5 C (temperature)
HEIGHT 90 METERS
DISTANCE 97 KM
Nothing, absolutely nothing could be seen from a distance of 97 km; moreover, as can be seen clearly, there are many buildings/lights observed in Oshawa, not necessarily the Summit Place building, therefore the elevation for those buildings can be reduced further.