16mm Tips
16mm TipsFor the most detailed information on using subminiature cameras visit the link page. There have been however a number of tips posted in the usenet, list and forums that are not otherwise available.
These include details on how to use a replacement battery for a QT and how to un-jam the shutter release.
I successfully used un-perforated microfilm in the Mikroma II camera - the only trick was to increase the take-up spool core by winding some paper on it prior to attaching the film. The frame spacing was not even but if there was enough paper on the spool (about to double the spool core diameter), it worked. The Mikroma normally allows 50 frames on regular thickness film.
With the thin microfilm, at least 30-40 exposures are possible (part of the take-up spool space is taken by the paper). The Mikroma seems to depend on the perforation at the first look but it worked as described anyway. Kamil Horák
- it depends on what you like to shoot!
This seems to be a perpetual issue in subminiature work. You have three options:
Joe McGloin (SubClub & Goathill)
There is a bit of handling and this resulted in some negative scratches in my attempt. You start with the usual 18 to 20 inches of 16mm film (I used unperforated) the trick is to tape the film to the takeup spool so it is EMULSION SIDE OUT. The other end of the film is rolled up emulsion side IN. You place the spool into the cassette and slip the film around the film guide (the emulsion side will face out) and tuck the rolled film into the remaining film compartment. You may need to turn the spool a bit to seat it. The film takes a hair pin turn to get behind the pressure plate. You should definitely practice on a scrap of film first. The Y16 is sort of a 110 cassette as the film plane is part of the cassette mechanism. Reloading the Rollei 16 or the Minolta 16 is much easier! Gun collectors might like the Y16 though, the only camera I know where the manufacturer refers it as having a "clip load". Charles Wong Submini-L, March 1997
Briefly
Ev = Tv + Av = Lv + Fv
Tv = time-value (shutter speed), where 0 = 1 second, 1 = 1/2 sec, etc.
Av = aperture-value (f-stop), where 0 = f/1, 1 = f/1.4, etc.
Lv = light-value (brightness), where 15 = direct sun and 12 = open shade.
Fv = film-value (film speed), where 0 = ASA 100, 1 = ASA 200, etc.
Note that when Fv = 0 (ASA 100), then Ev and Lv are equal.
EV's for f-stops:
f/1 --> EV 0
f/1.4 --> EV 1
f/2 --> EV 2
f/2.8 --> EV 3
f/4 --> EV 4
f/5.6 --> EV 5
f/8 --> EV 6
f/11 --> EV 7
f/16 --> EV 8
f/22 --> EV 9
And here they are for shutter-speeds:
1 --> EV 0
2 --> EV 1
4 --> EV 2
8 --> EV 3
15 --> EV 4
30 --> EV 5
60 --> EV 6
125 --> EV 7
250 --> EV 8
500 --> EV 9
Here's the important rule: The EV that your camera is set to is the SUM of the
f-stop's EV and the shutter-speed's EV.
For example, in one shoot I did, there was typical florescent lighting, which we
know from the exposure table is EV 7 at ASA 100. But I used ASA 800 film, so
that meant I should set the camera to EV 7+3 = 10. And I had an FL-DAY filter
over the lens to correct the
7+color, which removes half the light (1 EV), which makes it EV 9. I set the
camera to 1/30 at f/2.8, which is EV 5 + 3 = 8, which meant I overexposed the
film by one stop, giving me some room for error.
If your camera has EV's marked on the shutter, things are easier. If your meter
reads EV's, it's easier still: Set the ASA of the meter to that of the film,
read the light off the meter, and set the ring on the shutter to that value.
Then set the shutter speed to what you want; the aperture will adjust
automatically to maintain the same EV setting.
Finally, this was called the APEX System in the 1960's - APEX System (Additive
Photographic Exposure)
www.health.uottawa.ca/biomech/courses/apa4311/apex.pdf
Av = lg(fstop^2)
Tv = lg(1/shutterSpeed)
Sv = lg(filmSpeed/3.125)
Lv = lg(footCandlesSubject/6.25) (1 footCandle = 10.76 lux)
Then: Ev = Av + Tv = Sv + Lv
Examples: Given an exposure value of 10 and a subject brightness of 50
foot-candles (Bv=3), a film speed of 400 ISO (Sv=7) is required for proper
exposure. If an exposure time of 1/125 s (Tv=7) is used the aperture must be
f/2.8 (Av=3).
These calculations are simplified by using a light meter with a calculating dial
for determining appropriate apertures and exposure times. Some cameras have
built in lightmeters which indicate the appropriate aperture or exposure time
for a given film speed. Aperture priority cameras (AE) select the correct
aperture for a given exposure time. Exposure priority cameras select the correct
exposure time for a selected aperture. Totally automated cameras select both
aperture and exposure time to properly expose the select film speed.
To determine an appropriate aperture for a given film speed, subject brightness
and exposure time first set the film speed on the light meter. Next, meter the
subject to determine the subject brightness and exposure value (if available on
meter). After aligning the meter's dial with its measured brightness value find
the exposure time on the dial and read the associated aperture.
According to http://www.fredparker.com/ultexp1.htm (a good place to read about the EV system, and it includes an exposure value chart for many situations, such as candle-lit close-ups), EV 0 (at ASA 100) is .23 footcandles.
footcandles = 2EV x 0.23
Mark A Overton IDCC (Internet Directory of Camera Collectors) August 2006
Last updated 21st August 2006