To try out my Minolta 16 camera (£5 on ebay). I bought some Russian (Soviet 1982) 16mm B+W film. The 65 number refers to the Soviet film speed which elsewhere on the box is translated to 80 ASA and 20 DIN.
 |
| Russian 16mm film |
Loading the film onto old cartridges is simple enough in a changing bag after a little fumbling around. The first roll of film I exposed using a flash on automatic mode with a speed of 100 (The Russian film is actually ASA 80). I also developed using semi-stand development with a solution of 1+100 Ilford LC29 developer. Stand for 30 Minutes, invert and stand for a another 30 minutes. Stop and fix per usual. The results were under exposed and grainy. The film had some fog as well. The scan below shows one result and this is after optimizing for levels in Photoshop.
 |
| Stand Developed Russian 16mm scan. |
I thought the development was not good for this film and wanted to see where the film speed was best set for. I loaded and shot a new roll. This time out the back garden using a photometer. I ran 7 test shots 3 at 1/30th second and 4 at 1/100 second. The result below is a straight scan. of all 7 shots and their exposure values.
 |
| 1/30 f3.5 ASA 16 1/30 f5.6 ASA 40 1/30 f8 ASA 80 1/100 f3.5 ASA50 1/100 f4 ASA 64 1/100 f5.6 ASA 125 1/100 f8 ASA 250 |
The best results seem to be from the range of ASA 64-80. These were developed in a normal fashion in LC29 1+19 for 7:30 at 21C. This seemed to give a good range of density. The 1/100 sec exposures confused me. The f stops were metered at 1/125th second but shot at 1/100 sec exposure. I would have thought they would have been brighter not darker. I measured the shutter speeds and the 1/30th was true but the 1/100th was slow, perhaps as low as 1/60th so this didn't solve the problem. I decided to run another strip of test film and more carefully meter every shot.
 |
| 1/30 f3.5 1/30 f4 1/30 f4 1/30 f5.6 1/30 f8 1/30 f11 1/30 f16 1/100 f3.5 1/100 f4 1/100 f5.6 1/100 f8 1/100 f11 |
These were more consistent results. The third frame is a mistaken repeat exposure. The numbers on the scan are the metered ISO/ASA. In each exposure I metered the scene at the shutter speed and adjusted the ISO until the desire f-stop was achieved. At the same time I metered the scene I snapped the photo so I could be consistent. I metered the lawn in every case. I also used a tripod to keep the scene consistent. Again the 1/100 sec exposures showed dark and all I can conclude is that this setting is still much faster that 1/30th and so darker.
I have played with Photoshop as an analysis tool to use the scanner as a densitometer in previous posts. This should provide a means of objectively evaluating the results. In this case I selected a larger area in each photo and measured the mean and standard deviation. These I used as proxies for brightness (mean) and contrast (std dev). I plotted these against ASA ISO from above.
 |
| Add caption |
The results shows the falling brightness against rising ISO rating. Contrast peaks around ISO 25 though brightness falls off noticeably.
Finally I cropped and adjusted using Auto Levels in photo shop the ISO 10 and ISO 25 results.
 |
| ISO 10 No Levels |
 |
| ISO 10 Auto Levels |
 |
| ISO 25 No Levels |
 |
| ISO 25 Auto Levels |
Comments