Pentax Modified meter/ How to use it???

greenspun.com : LUSENET : Large format photography : One Thread

Ok, I got my hands on a modified 1 degree pentax spot meter. Lets assume it's modified correctly, for now. Do I take a reading and then move the ev scale to where I think the EV say 6 should fall on Zone 2. If this is correct, do I look right above the 6 to see that the F stop is 1.4 or what??? How would you use this low F stop at all. I am planning on using Ilford 125 film.I have no directions, and this is my first light meter, and my first camera and though I think I understand the Zone system basically, I just don't get this meter at all. What do I do with the first dial after I figure out the other one? I realize my ignorance is showing, but it is the only way of learning something from someone else, that I know of, the past posts are kind of vague, if anyone could be very specific I would appreciate it. Thanks for the help, and have a good holiday. Hallie

-- Hallie Brant (arborealmama@hotmail.com), December 27, 2000

Answers

Hallie, i have an old Pentax spot meter, its not the digital one and it's not modified either. Basically, you point the circle (the one that is seen when you view through the meter) at the areas that you wish to meter and you press the trigger. This activates the needle in the meter to point to a number in your view finder. For example, let's say it points to "12" exactly.

Then viewing your dial on the side, making sure that the asa is dialed in correctly, you turn the outer ring so that "12" on the bottom row of the dial is in line with the arrow. Looking at the top row, this will give you all the possible shutter speed/ aperature combinations for that exposure.

If you count the difference in EV numbers between your highlights and shadows, you will get a quick idea of the zones.

I hope that answers your question. It seems complicated but it really isn't.

Dave.

-- Dave anton (daveanton@home.com), December 27, 2000.


First set the film speed ring to the film speed you want to use. The film speed ring is the outermost ring and it has green numbers, with "ASA" to the far left. Then point the meter at whatever subject or area you want to read. Pull the little trigger and you'll see an EV reading. Move the EV dial on the meter (that's the dial that says "EV" to the left and has orange numbers on it) to the zone on which you want that subject or area to fall. For example, I would normally first take a reading of the darkest area in the scene in which I want detail. Let's say the EV shown for that area was 8, just to pick a number. I would move the EV dial until the number 8 was opposite the zone on which I wanted that area of the scene to fall, usually zone IV for me. Then I would take a reading of the brightest area of the scene that I cared about. Lets say that reading was EV 12. I would look at the zone system dial and see on what zone EV 12 would fall given the placement of EV 8 on zone IV. If 8 is placed on zone IV, 12 would fall on zone 8. That might or might not be acceptable. If it was acceptable then I would leave 8 on zone IV and select a shutter speed/aperture from the selections shown on the f stop and shutter speed rings (the two middle rings, one of which has numbers in white and the other of which has numbers in blue). With EV 8 placed on zone IV, and a film speed of 200 (for exaple), I have a choice of shutter speeds/apertures ranging from F 1 at 1/1000 second to F 128 at 15 seconds (these extremes are unrealistic of course but they are the ranges shown on the shutter speed and aperture dials). Of course you can take more than two readings to see on what zone other things in the scene will fall given placement of EV 8 on zone IV (in my example) and you might decide that EV 12 falling on zone VIII is unacceptable, in which case you would move EV 8 down to zone III, which would then place EV 12 on zone VII. Since you have a modified meter I'm assuming that it has the little zone decal showing zones I though VIII on it. That isn't a necessity but it does make things a little simpler. Hopefully all of this is reasonably clear. If not, send me an e mail. You could order an instruction book from Pentax for about $5 but I don't think the book goes into any detail on zone system work. Still, it might be useful.

-- Brian Ellis (bellis60@earthlink.net), December 27, 2000.

The Zone VI modified meters included a Zone Scale. If you read 6 and want it to fall on Zone II, you turn the ring to set 6 on the "II" mark on the scale. (You need to set your film speed before you do anything. That's another ring around the lens.)

The lower Zones (I, for certain, and possibly II) are beyond the window opening. If, for example, the Zone II mark is beyond the window, set one EV higher on one Zone mark higher (set 7 on Zone III, in thix example).

If the meter is missing it's Zone Scale and you want one, I think Calumet still sells them.

Alternately, set EV 6 on the middle mark (I think this is a triangle, but it corresponds to Zone V), while counting down in zones from V, move up one EV number for each count. Example:

Starting: EV 6 on Zone V Move EV 7 to Zone V and count "Zone IV" Move EV 8 to Zone V and count "Zone III" Move EV 9 to Zone V and count "Zone II".

That's your setting. (You've just set EV 6 on 3 zones down from V, which is Zone II).

The shutter speed dial & f-stop dial gives you many combinations that result in the same exposure. Thus, if you get f 1.4 at 1/500 (not possible with many lenses, and not optimal on many more), you also get these combinations:

f 2 @ 1/250 f 2.8 @ 1/125 f 4 @ 1/60 f 5.6 @ 1/30 f 8 @ 1/15 f 11 @ 1/8 f 16 @ 1/4 f 22 @ 1/2 f 32 @ 1

Depending upon your scene, you can select the shuter speed to stop motion as needed and/or f-stop to get the depth of field you want.

For reference, the old rule of thumb for exposure without a meter was called "sunny 16": On a bright, clear day, during mid-day hours, not at the beach or in snow, use f 16 and expose for 1 divided by the film speed; thus for 125 film, use f-16 at 1/125th of a second. Close down 1 stop (f 22) for extra bright scenes (at the beach, in snow, etc., where there's a lot of light reflected by the surroundings). Open up 1 f/stop for partial clouds, 2 f/stops for mostly overcast.

This can give you a point of reference to see if the meter readings you are getting and your exposure placements make sense. For example, if your EV 6 on Zone II gave the options above, it hints you are either using exceedingly slow film on a bright sunny day (not really possible, since there aren't any films this slow) or you are more likely indoors or in extreme shadow. Or you didn't set the film speed, or your battery needs replacing.

-- Charlie Strack (charlie_strack@sti.com), December 27, 2000.


I have a Pentax analog meter, and I use it in the following fashion. I will preface this "brief" discussion by suggesting that you ignore the Zone VI sticker that's placed on the dial. You don't really need it. (In my opinion.)

Let's assume that you've found a location that you want to place on Zone III (or whatever zone you decide), and that it reads an EV of 9 in the meter. The difference is 9-3=6. Thereafter, simply subtract 6 from the EV that you read in the meter for any other reading in your scene. The result of this subtraction will be the equivalent reading in the zone system, with respect to initial Zone III placement. e.g. an EV reading of 13 on a leaf would then equate to a Zone VII, since 13-6=7.

If you decide that this Zone III placement was too low or too high, select another part of your scene, and try a different placement. For example, suppose you find another portion of the scene that you would like to place on a Zone IV, and that the EV for this reading is 12. The difference is 12-4=8, and so you would subtract "8" from every other EV reading to get the zone equivalent with respect to your Zone IV placement.

Continue this process until you find a placement that you like, and that allows for the amount of contraction or expansion that you think appropriate. Add "5" to the difference that you subtract, and that will yield the EV that you should set on your meter for the proper exposure. Going back to the first example above, let's suppose that the Zone III placement that you tried initially is the best. Since the difference in that example is "6", add "5" to "6" to get 6+5=11. Use an EV of 11 to determine your correct aperture and shutter speed on the dial.

While a little lengthy to describe, this system is intuitive, quick, and easy to use. It doesn't require you to look at the dial every time you want to take a reading. You need only look at the dial to set the shutter speed and the aperture.

-- neil poulsen (neil.fg@att.net), December 28, 2000.


Hallie, get hold of The Zone VI Workshop by Fred Picker, and read it through and you will have a much better understanding of the zone system and how your meter works (Fred and Paul are the one who came up with the modified meters to begin with), there are others out there but Fred is easy to understand and simple, and do the film speed tests and do the print tests if you are doing your own printing, which ever school of thought you decide on, stick with it and don't jump around from one person to the next, that way you will develope a sound understanding of the basics this takes a lot of repitition in the school of thought you have chosen, then after about a year think about experimenting with variations, in other words get the basics down before you start playing around. Pat

-- pat krentz (patwandakrentz@aol.com), December 28, 2000.


Moderation questions? read the FAQ