Those old time cameras had such great clarity and depth of field.
It's amazing how sharp an image can be when the pixel size is that of a silver nitrate molecule. By my calculation, a 4"x5" photo would have about 310M Megapixels (310,000,620,001,240). Maybe there's a photographer (or photography scientist) here who understands it better.
Richard L.
Edit: Maybe that should be stated as "310 Trillion pixels?[/color
How quickly things are forgotten
Film came in ASA ratings which was a measure of the grain size and determined the exposure time
And you could get it from 80 to 400 for standard film or 100 to 600 for slide film
There were more grades availible for professionals but it became very expensive very quickly and processing was even more expensive .
The story was the same with printing paper
B & W was graded with letters and colour was graded with numbers
Depth of field is simply a function of the quality of the lense, aperature size , exposure time & film grain size.
With SLRs you could set the depth of field that you wanted .
The histance of the lense from the film plane set the front of the focal plan & the apperature set the back of the focal plane
We got very used to fashion photography where the depth of fiels is set very shallow so the model is clear & the back ground is fuzzy.
This was done to make you pay attention to what the model was wearing and also to disguise the location of the photograph
Then there was the stock size
For printing out to the old 6 x 4 or 8 x 5 any film from 8mm to 35 mm was fine ( using the right grade of film )
for larger print you needed a magazine backed camera for stills or a 120 for action.
I used to have a Roliflex 2.5 x 4 and a Leitz 3 x 4.5 and boy was I happy when I got the bellows for the OM2 so I could forget about cutting up sheets of film under safe light and loading magazines .
In the days of no cost digital photography we forget that a roll of good film would set you back 3 hours wages and processing was about a full days wages which is why magazine backed cameras remianed the norm for newspaper right up untill the 70's.
As for the shot itself, yes probably done with a magazine backed camera, and better than average chance it was a publicity shot for Matchless
Note all of the bikes are parked perfectly parallel so they are all in clear focus
You can just about make out the grins the people are trying to conceal
And if you run them past some older enthusiasts you will probably find they were period racers of some type who were generally used for road testing new bikes & of course publicity photographs .
Now if you really want to play with numbers
Silver Nitrate has an atomic mass of 170g/ mole
Avergardo number is 10 to the 23 atoms per mole
A roll of 35mm stills film has around 400 mg of recoverable silver
Oh and one grain of silver halide can have a gradient frm one side to the other so 1 grain does not necessarily = 1 pixel
And a pixel is not a fixed size .
