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The
Ultimate Monochrome Print
Without
a Densitometer
by
Jon P. Fishback
For
years I worried about a simple way to explain the method of exposure from the
negative through the print. I always approached the problem as if it had two
solutions: one for the negative and one for the print. I have discovered the
error in my thinking. There is only one problem, and only one solution ------
THE PRINT.
MAKING
THE ULTIMATE MONOCHROME PRINT
The
negative's only function is to make the print. The print is the only part of
the process that is shown. A 'perfect' negative, as far as the densitometer
is concerned, can still be a frustration if it will not print straight.
One
solution is to custom-make the negative to print perfectly on your choice of
paper. The limitations of the paper should be a primary concern. You must
keep the final print and paper in mind at all times.
The
approach to the final print starts with your selection of paper. Since this
process must be repeated for any paper change, it is a good idea to start
with your favorite paper.
Next,
the negative material will be selected. I will discuss an ISO/ASA 400 film.
STEP
ONE: develop unexposed film
Using
your usual technique, process an unexposed roll of film, or two sheets. The
result is a negative completely void of exposure. It will be the clear film
base and any small amount of fog that is inherent in this film. Cut the roll
as you usually do and save the frames, or the sheets, for step two.
NOTE: The enlarger height and lens aperture
will remain the same throughout these tests. Set the aperture to your usual
working stop, probably but not necessarily f/8 or f/11, to obtain the results
that follow.
STEP
TWO: the PV (Print Values) concept
The
next step will be to experiment with your paper and what we will call its
PRINT VALUES, or PV. PV5 is the same in the print or the negative. A negative
density of PV5 will render a middle gray print tone, which will also be
called PV5.
First,
place one of the clear negatives created in step one in the enlarger, and
raise it so the light through the focused area covers an 8x10 easel. Use a
whole 8x10 sheet. With all but about 1/2 inch of paper covered, make a 3
second exposure with the lens set at a convenient aperture. Continue this to
the bottom of the paper moving the cover 1/2 inch each time. Develop, stop,
fix, wash, and completely dry the test print before going on.
Next,
check the print for a maximum black strip. The maximum black strip will be
the one that is the same black as the strip that follows it. In other words,
look for two adjacent strips of equal black density. To find the exposure
time for this maximum black, count the strips from the light end by threes
until you find that strip. If there is no black strip that meets this
criterion, the paper needs more exposure. Open the aperture slightly and
start over. If the darkest strip is very close to the light end, close the
aperture and begin again. The darkest strip should fall near the center of
the sheet. Once this exposure time has been established, write it on a small
piece of white paper, and tape it to the test print strip. This time will be
used later as the exposure time for the PV8 test. Mark this as PV0/PV8.
Definitions
of PV0 and PV1, or Darkest Tones:
Now
comes the subjective part of the experiment, and one that is very important.
You must decide which shade of black you see as PV1. Just a note here to help
in the selection. PV0 is a black defined as the pure absence of light. This
will be rendered by the paper as the blackest that it will get, as in the
previous test. A shade of gray just above total black will be PV1. Only you
know what you see as PV1. It will be an area above total lack of light, the
shadow area of the print that just shows detail. View the print using the
exact light you feel all your prints deserve. Clearly mark the PV1 strip on
the test print with the exposure information just as you marked PV0.
Definitions
of PV9 and PV8, or Lightest Tones:
The
next test strip print will find PV8, or almost-pure paper white. PV9 will be
considered pure white paper base tone.
As
before, make the test strip by moving the cover sheet in 1/2 inch increments
down the print. The major difference: Do not expose the last strip. Leave
this area pure paper base white, or PV9. Use extremely short exposure times
for these strips, or stop the enlarger lens down. Most good electronic timers
allow for 1/2 second, or slower, exposures. If you do not have this type of
timer, work with what you have. The point is to use very little light to make
this test strip. You may have to make several test strips in this section of
the test to get the correct one. Do not try to take short cuts. This is a
most important part of the experiment.
When
you have a dry test strip with a pure white and several very subtle shades of
gray, find a shade of gray just below pure white. This will be your PV8.
Think of PV8 as being all the white areas of the print except specular
highlights. The sun shining off of a chrome surface is PV9. All other white
areas of the print will be PV8 or below. Pick the PV8 area very carefully.
Think about what shade of white you wish to see in your print that is just
below pure paper white. Keep in mind that few things in a print are pure
paper white. Carefully mark the shade of white you choose with its exposure
information. This exposure information may be written on the strip.
Using
this clear negative, and the exposure time, enlarger height, and lens
aperture that created the PV1 test strip, make an entire 8x10 print using
that exposure, and mark it as your final PV1 test print.
Do
the same thing using the PV8 exposure previously saved.
Mark
both prints with all information used in their creation. Treat these two
prints as you would any other prints. That is, if you tone your prints, do the
same with these. Always air dry the prints.
STEP
THREE: Personal Exposure Value (PEV)
Two
things will happen in this step. You will derive a negative that will print
as PV1, corresponding to your PV1 test print, and you will determine a
Personal Exposure Value (PEV) for your film, equipment and technique. The
manufacturer's recommended ISO/ASA rating is only a recommendation, and is
not necessarily valid for your equipment and/or process. You must determine
your own PEV.
Start
with a blank evenly-toned mount board. Any color will do. A middle tone is
best. Load the camera and frame the middle of the mount board which is placed
in rather weak light, as ASA 400 is quite fast. I use interior daylight
illumination from a north-facing window. This allows me to move the mount
board away from the light source, to adjust the amount of light.
Make
sure the board is evenly illuminated. Set the focus on infinity. The
manufacturer's recommended ISO/ASA for the film I used is 400. You will try
ISO/ASA ratings from 200 through 800. Use a reflected-light meter. A
spot-meter is best, but any good reflected-light meter will do. Start by
setting the ISO/ASA on the meter to 200. Meter the board along the axis of
the lens and again make sure it is evenly illuminated. You should be close
enough to the mount board that you meter only the board. You will make
negatives that seem to be underexposed by four exposure values. A
reflected-light meter gives exposure data for PV5.
NOTE: Any evenly illuminated and single-toned
subject will be rendered as PV5 if exposed exactly as the meter tells you.
That is, meter a 'white' object, and it will print gray. Meter a 'black'
object: it will print gray.
With
the meter set at ISO/ASA 200, and after metering the board, pick a shutter
speed and aperture combination that will allow you to reduce the exposure by
four (4) exposure values and still have two smaller F-Stops to use. The board
I metered gave me an Exposure Value of nine (9). I will use this as the
example. This allows me to pick 1/60 at f/4 as a starting point, and 1/250 at
f/8 as my -4 reduction. I still have two smaller F-Stops as my lens stops
down to f/16. This may seem to be intentional underexposure. In reality, all
it does is expose the negative for PV1 using ISO/ASA 200. (PV5 - 4 = PV1).
Make
a small note on white paper and tape it to the mount board, so you can see it
through the camera. Put the starting PEV (200), Shutter speed
("S"), and Aperture ("A") on the note. (See Example 1)
EXAMPLE
1: [A = the aperture you have used, S = shutter speed you have used]
APERTURE
-- A
SHUTTER
-- S
PEV--
200
PV1
TEST
Make
the exposure at this setting. The note, as viewed on the developed negative,
will be your record. Now close down the lens by 1/2 stop. Example: From my
current f/8 I would stop down between f/8 and f/11. Change the note attached
to the board to show the change. (See example 2)
EXAMPLE
2:
APERTURE
-- A+1/2
SHUTTER
-- S
PEV--
300
PV1
TEST
Make
another exposure, and continue reducing the exposure as shown in Table 1 up
to PEV 800. You may reduce the exposure any way you wish, as long as it gives
the equivalent of that shown in Table 1. If you were not careful in picking
your shutter speed and aperture combination, you will not have two F-Stops to
reduce the exposure. In this case it will be necessary for you to adjust the
shutter to make the additional exposure reduction to reach PEV 800.
TABLE
1
APERTURE SHUTTER PEV
A S 200
A+1/2
stop S 300
A+1
stop S 400
A+1.5
stop S 600
A+2
stops S 800
If
you are using roll film, expose the remaining film on anything, to make the
development more uniform. Develop the film in your favorite developer at the
usual time and temperature.
After
fixing, washing, and drying the film, separate the frames, and print each
frame or sheet of film on the same type of paper that was used in the test
print. Use the enlarger height and lens aperture that were used on the test
print marked PV1. Expose each negative for the same time used to make the PV1
test print.
Find
the print that is the best match to the PV1 test print. Once you have found
this print, you have found your Personal Exposure Value -- PEV. Simply look
at the note that appears in the corner of the print: it was the note
photographed on the mount board, and it shows the PEV to use for this film
and paper combination.
STEP
FOUR: Exposure for PV8 development
This
step will expose the film in preparation for the PV8 development. Return to
the camera with the new PEV rating for the film. Reset the meter to this PEV.
Expose
four sheets of film, or four rolls, at PV8. To do this, meter the board using
your new PEV rating. Pick a shutter speed that will allow you to open the
aperture by three stops after the base exposure has been determined. This
will seem to overexpose by three stops, but remember what was said earlier
about the meter giving you PV5 data. Thus opening the aperture by three stops
only brings you to PV8. (PV5 + 3 = PV8). Expose the four rolls or the four
sheets with the aperture opened up by three stops. Example: If the meter said
to use 1/60th at f/11 with your new PEV, then the PV8 exposure would be
1/60th at f/4.
STEP
FIVE: Development time needed to obtain a PV8 highlight
This
procedure will determine the exact development time needed to obtain a PV8
highlight on your paper.
Process
one sheet, or one roll, in your usual manner. Make a print with the sheet of
film or a frame of the roll. Use the same enlarger settings as for the other
test prints, and use the exposure time used to make PV0. This is the one
marked PV0/PV8. This time gave you maximum black through the clear film in
step two. This time and exposure should give you PV8 through this negative as
well.
As
you can see, one exposure time must render black, all shades of gray, and
white (i.e. PV0 through PV9) if these values are to appear in your rendition
of the original scene.
After
having washed and dried the print, compare it to your PV8 test print.
Determine if it is too dark or too light. (It is doubtful you will be so
lucky as to get it correct the first time.) If the print is not just like
your PV8 test print, adjust your film development time to compensate. If the
print is too dark, increase your film development time. If it is lighter than
the PV8 test print (this means that it must be pure paper white), you must
cut back on your film development time.
Use
the next exposed sheet (or the next exposed roll) of film to make another
negative, with the development time changed. You may use any convenient
period of time in changing your development. I increase or decrease 10% and
round it off to the nearest minute.
Example:
On a nine (9) minute development time I will use plus or minus one (1) minute
each time a change is necessary.
Continue
this until you have a negative that will print the exact tone of your PV8
test print. At this point you have determined your film development time.
CLOSING
NOTES:
At
this point you should know the PEV (Personal Exposure Value), or adjusted
ISO/ASA, for your film (to derive a PV1 shadow). You should also know exactly
how long to develop the film to get a PV8 highlight on your paper.
This
test has been done using your favorite paper, and not a densitometer. The
final result is determined by the quality of the print, not how the negative
looks.
This
process will not replace the Zone System or manipulation of the photographic
process in general. There are too many variables in nature and too many
personal preferences to ever have a universal system for print making.
This
is a starting point meant to keep the limitations of the materials primary
when you decide how to make the exposure.
There
are many variations on this process, but the basic concept remains the same:
We are at the mercy of the photographic paper. You can get no more from the
paper than it has to give.
The
negative must be made to print on the paper that is available. Manipulation
of the negative through development will not help if the result can not be
printed. It is possible to make a negative that has such a wide range of
tones, and has so many subtle densities, that it will not print on any paper.
This procedure will show you how to tune your negative to print on your
paper.
This
is only a beginning, the beginning that is most important to the ultimate
monochrome print.
Copyright
Lloyd Erlick. All rights reserved.
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究極黑白放相製作
免密度計
底片、曝光、顯影、負片、放相，這幾年來在不同場合要解釋這些事情，一直想找個簡單的方式來講，但終究是困難，走純理論開始固然是我的習慣，但這不是受眾的習慣。不過我始終相信，這裡頭的謎團看似龐雜，但只要梳理清楚，把握最上位系統的觀念進行推演，拍照，尤其用底片拍照，那絕對是世界上最輕鬆的嗜好了。
負片唯一的用途就是用來放相，而相片是整個處理程序唯一可見的部分。如果擁有一架密度計，卻無法對一格「完美」的負片進行直接放相，那無疑是令人感到挫折的。
有一個解法是這樣的，根據你選用的紙張製作你的負片，也就是說紙張的極限會是第一順位的考量，我們應該經常將final print和用紙擺在心裡。
製作final
print的規畫始於用紙選擇。由於底下的測試流程不管用哪種紙都得重作，建議就從你最喜歡的紙張做起吧。
其次才是挑選底片，以下我只討論 ISO 400的底片。
第一步:
沖洗未曝光的底片
用你平常習慣的方式，處理一捲未曝光的底片。你會得到一捲完全沒有曝光影響的負片，就只會有片基(film base)及一些固有的灰霧(fog)密度在上頭。剪成你習慣的長度之後，我們進到第二步去。
注意: 放大機的高度及鏡頭光圈值在整個過程的設定必須不動。所以光圈值還是設定在你習慣的流程數值，通常是f/8或f/11，不過這不一定，看個人習慣。
第二步:
PV(Print Values)的理論概念
這一步就開始要測試紙張的PV。一般來說，我們會讓相片和負片上的PV5一致。負片上的PV5密度要落在相片階調的中間灰，也就是相片上的PV5。
首先，把第一步弄出來的白片架上放大機，高度設定在能夠放相8x10相片。拿出一張8x10相紙，先遮蔽一段約莫0.5英吋寬的相紙，曝光3秒，接著再遮蔽一段0.5英吋寬的相紙，曝光3秒，重複直到遮蔽完整張相紙，接著就你習慣的流程，顯影、停止、定影、水洗、乾燥。
等到乾燥以後，檢查相片上最黑的那一條。假設存在第X條與第X+1條的黑，你無法分辨是第X條與第X+1條的黑色差異程度，那麼第X條就是最黑的那一條，看看要製造出這最黑的一條需要多久的曝光時間，純白的第一條曝光時間為0，以後每一條多3秒，加減而已。如果在相片上找不到二條一樣黑的，那就表示曝光時間總長不夠，請將光圈開大一點，增加曝光強度，從第一步重新來過。如果最黑的一條太靠近，則是把光圈開小一點。一般而言，我們希望最黑的那一條可以出現在靠近相紙中間的位置，這對以後比較方便。一旦曝光時間確定之後，將之寫在一小張白紙，貼在相紙試條上頭，這個曝光時間將會用來進行下面的PV8測試。標記為PV0/PV8吧，待會用的到。
PV0和PV1的定義，或者說最暗的定義:
現在要開始製作相對主觀且重要的測試了。你必須決定你看到的那些暗部，暗到什麼程度的要落在PV1。這裡有個方式可以幫助選擇，PV0是完全無光的黑暗。這會落在剛剛做的試條最黑的那一條上頭。PV1大概就是一片黑暗裏頭有那麼一點極深灰。不過，只有你自己知道你將哪裡「看成PV1」。那會是個只比完全無光區塊亮一點的區塊，在相片上的暗部會看到一點細節。記得用你認為觀看相片時要用的光強度去找PV1，找到之後一樣標記起來PV1。
PV9和PV8的定義，或者說最亮的定義:
接下來要找PV8，呈現將是幾乎只有紙白。PV9則是只有紙基調子。
如同前面搞試條一樣，請進行0.5英吋試條放相程序。最大的不同只有「對最後一條不曝光」，那就是PV9。分段曝光時間則調到極短，每0.5秒一段或更短時間，重點就是分段曝光時間要很短。這一步挺重要的，別忽略不做啊。
當你搞到一張具有紙白及數段具有微妙灰色的試條之後，請找到只比紙白灰一點的那一段，那就會是PV8。PV8將會是除了相片上極度高光的區區以外的白色區域。PV9大概是陽光照在上頭的銀色金屬反光面。其餘區域就是在PV8以下，挑選你的PV8吧，想想你想把相片的那些區域搞成僅僅只比紙白暗一點點，同時也請記得總有些東西會變成只有紙白。一樣，把曝光數據紀錄在試條上頭。
接下來把從PV1試條得到的曝光時間、放大機高度、光圈值，對那一條白片進行完整放相程序，乾燥之後，那就是你的final PV1 test print了。
Final
PV8 test print也是一樣作法。
如果你習慣做其他處理(比方說調色)才出final
print，那麼也請對這二張final PV1/PV8 test print做一樣的事情。
第三步:客製化曝光值Personal Exposure Value(PEV)
第三步要幹二件事。會搞出一條負片可以放相成PV1，並且根據底片種類、器材及處理程序決定出PEV。原廠建議的ISO不是說不能用，但那終究只是個建議，那並沒有根據你的器材和程序匹配，PEV還是得自己搞出來。
先搞來一塊顏色均勻、平整的大塊板子，顏色如果是中間灰會最好操作，不過其實什麼顏色都可以。將板子放在弱光下，原廠ISO 400底片的話，就北邊窗戶射進來的室內陽光吧，沒有直射的強光源比較好調整位置，接著把習慣用的相機拿來，靠近板子，並且對準中間。
記得要讓板子均勻受光。將相機對焦在無窮遠，用原廠ISO 400底片的話，接下來請從設定成200做起，這一路可以做到800，甚至1600也行。使用反射式測光表，有點測光的也不錯，但任何反射式測光表都行，建議就用相機內建的，反正你出門也都是用它。首先設定成ISO 200，拍下去，測光表給出的數據會讓這一格拍成PV5。
注意: 只要是按照測光表的數據去拍，任何均勻受光且單一色調的物體都會被拍成PV5，也就是說如果對著白色物體測光並拍攝，放相時候那白色物體就會是灰的，對著黑色物體測光並拍攝，放相時候那黑色物體也會是灰的。
現在你有了一組光圈快門組合，挑個至少還可以2組相對小的光圈值可用，而且能夠能夠減4格EV的拍攝任務吧。舉例而言，我測到EV of 9，假設一開始光圈快門是1/60 at f/4，那麼減4格之後就是 1/250 at f/8，而我的光圈值再小2格還有f/16可用。這樣拍的話，就是將底片設定在ISO 200時，將負片曝光出PV1的設定。
在板子上貼張便條紙，以便能夠透過鏡頭看到，上面要寫目前PEV是多少、光圈多少、快門多少。
光圈A
快門S
PEV
200
PV1 測試
開始拍攝。拍一格或若干格都行，接下來每次遞減1/2格，便條紙記得要改啊:
光圈A+1/2
快門S
PEV
300
PV1
TSET
一路重複直到用PEV 800拍攝。記得啊，一定一開始要留至少2格更小光圈，不然無法做完測試。這樣一路減半格測下來，就是PEV200、300、400、600、800。
接著是沖洗底片，如果是35mm片子，就用你習慣的顯影藥劑、時間和溫度吧。
沖程完畢，乾燥之後，把每一格不同PEV的底片放相出來。就用PV1 TEST所用的放大機高度、放相光圈、放相曝光時間。
找到用PV1
TEST數據的最佳放相，這裡的最佳就是要跟final PV1 test print長相一樣，那就是你的整套匹配的PEV了。
第四步:
尋找配合PV8顯影的曝光
這一步將會針對PV8顯影來對底片曝光。現在把你的相機設定成剛剛找到的PEV吧
現在請把4捲底片曝光到PV8。用PEV設定的底片，相機對準板子測光，挑選一個讓你有可以再大3格光圈可用的快門。現在把光圈開大3格，拍掉一整捲，依序遞減1格，直到拍掉四捲。
第五步:
尋找搞出PV8高光的顯影時間
這一步將會決定確切的顯影時間以利在相紙上獲得PV8高光。
有4捲底片，對吧？先拿一捲來照你平常沖洗習慣處理，放相出來，曝光時間則是之前做出來PV0的時間，一個讓你得到未曝光底片最黑放相呈現的時間，這個放相曝光時間照道理也得能夠這格負片在相片上呈現出PV8。
這裡做個小結，我們在做的事情其實就是希望一個放相曝光時間，就要搞出能夠呈現你認為的現場的黑、中間調及白。
把剛剛的print和PV8 test print做個對照，看看相對來說是太暗還是太亮，再對顯影時間做出調整，太暗，增加時間；太亮，減少時間，我建議是以10%為調整單位，在這左右選個方便時間來沖，別弄什麼調整17秒23秒之類的不方便。
好啦，決定好時間之後，請拿出下一捲曝光過的底片，乖乖沖洗，並且放相吧。
重複弄，弄到你能夠決定有沖出PV8高光的顯影時間。
注意:
到這裡你已經能夠搞定二件事，1. PV1 PEV，這就是曝光控制暗部，2. PV8顯影時間，這就是顯影控制亮部。
整個測試都沒有用到密度計，很家用的做法，最終結果使用放相呈現來決定，而非負片長相。
不要，這個測試並不能取代ZONE SYSTEM或攝影過程中的其他處理(比方說局部加減光)。畢竟影像呈現是相對個人化的要求，自然變數和個人偏好很難搞出一個百分之百統一的放相系統。
不過這個測試是個大方向上一致的起點，也就是根據材料極限來控制曝光，而不是毫無根據的亂猜。
過程中有許多變數，但是最根本的概念是一樣的: 我們都受相紙所擺佈，相紙沒有的，你也弄不出來。
而負片必須能夠在相紙上放相出來。任何放相放不出來的負片沖程伎倆都沒有幫助。事實上，我們根本就可以做出一個擁有超長階調的負片，上頭有著許多微妙變化的密度，然而無法呈現在相紙上。這個測試能夠幫助你調整出匹配現有相紙及系統的負片。
這只是個開始，卻是個追求究極黑白放相的開始。
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