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  1. #11

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    excellent images jd, but i want to see the results of "heavy testing"

    Ray

  2. #12
    jd callow's Avatar
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    I don't do heavy testing. I find the EI speed for a dev. (testing takes a couple sheets of film) for expansion and contraction I play it by ear. I tend to only shoot PXP and mostly just TXP so I'm pretty sure of my results. Or I was I will be using the semis stand technique going forward which will probably require some trial, error, and testing.

    *

  3. #13

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    My way of working is to find the exposure in the camera that will provide sufficient detail in the shadows whilst using "standard" development times to give a bright reasonably contrasty negative that will print on a G2 or G1.5 on a multigrade enlarger i.e De Vere with Ilford 500H light source. This will ensure luminosity in the image.

    I contact print all images on G2 by setting an exposure that will just produce maximum black through the film base- I in fact use the Ilford 500H probe to do this by taking a reading through clear film base and applying a correction constant I know works, then exposing for this. This will give you at a glance the images that will print optimally. Of course there are other images that can be printed but with more effort by grade and exposure chnages with burning and dodging and more.

    You don't need a De Vere to do this all you need is any enlarger and a test strip. Set the enlarger at a height for the contact sheet and at say the most likely aperture you will use e.g. 75cm & f8 then put a piece of blank film from the film you are about to assess into the negative carrier. Make a step wedge on G2 paper and choose the first maximum black exposure time. Remove the film base neg from the carrier and expose the contact sheet for this time, and give it standard print development. You can then select a frame that looks right, put it in the carrier in the enlarger at the same column height and f setting and make a print at this exposure - it should be a perfect proof print.

    This is perhaps the best form of quality control you will get - it works and will show you over a period of time any changes in exposure that are occurring in the camera or film variables

    Then go to the computer and set up an exposure and development record
    i.e. Film type, date exposed, date developed, ASA rating, camera, lighting conditions, developer, time, temperature, agitiation, tank, stop, fix, wash, and anything else you feel relevant
    By doing this you will have an invaluable database from whence you can tweak the results to get what you want for your purposes whether enlarging or scanning
    When I develop negatives I go bo to my database to see what I did last time with a given film/ cameras combination for bth exposure and development

    I have created a simple calculator in my spreadsheet for temperature differences which are critical to the end result. I also have one for printing to calculate the effects of changes in the enlarger column height for print exposure, which reads out in secs but also a guide for fractional f stops so that I can easily increase exposure by 1/6 stop etc

    And thats all there is to it no endless testing routines just keeping a close eye on things but being very methodical

    Hope this helps

  4. #14
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    Quote Originally Posted by Ray Heath View Post
    ..... but i want to see the results of "heavy testing"

    Ray
    You can't be shown the value of establishing a personal EI and dev times through testing------you have to experience it.

    I think that you are missing a basic concept as to why some people test for personal film speed and dev times. IMO, "heavy testing" is a complete mischaracterization and serves only to turn people off from what could otherwise be a very enlightening experience. It is as difficult as you make it and I guess you will either accept its potential value to your photography or you won't.

    There is no magic image post that will satisfy your request. Film testing is what it is; IMO, it provides for a predictable means to an end. Ansel Adams wrote:

    "the final print should be the Alpha and Omega of photographic procedure. It should be visualized before the negative is exposed."

    If you do not accept that premise and it is clear that noone has to to make good photographs, then testing serves no purpose for you. Visualization of the final image is supported by careful exposure and development of the negative in a way that is predictable and repeatable each time the shutter is released and film is developed.

    Chuck

  5. #15
    Thomas Bertilsson's Avatar
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    Some Contrast

    Just as a contrast to the whole discussion.

    This is shot with a Holga camera where nobody really knows what the aperture or shutter speed is. Tri-X film, developed in Pyrocat-MC at 1+1+100 dilution at 70*F for 16 minutes agitating continuously for the first minute and then two light inversions every three minutes (because that gives the best compromise in printing these wildly inaccurate negs that the Holga produces).

    No negative coming from a Holga is perfect from a technical standpoint, due to the light fall-off. If I printed this neg with technical perfection in mind, the whole center of the image would have no impact at all.

    I am of the belief that if you are a photographer for purely artistic reasons, perhaps a perfectly exposed negative isn't necessary. The imperfections make you a better printer anyway.
    If you, however, are a person interested in commercial photography, where the quality of your exposures are absolutely critical to whether your portraits or wedding photographs sell or not, then it's a different ball game.

    I am well aware that the image I have attached might not appeal to a majority of the population out there, but it appeals to me. It's how I like it, and I'm just merely showing that I get by just fine by flying by the seat of my pants as far as exposure / development tests go.
    For me, being obsessed with technical quality of my negatives and ultimately my prints was a detriment. Not until I let that go and started feeling my way with my photography did I grow as a craftsman.

    - Thomas
    Attached Thumbnails Attached Thumbnails 2007 06 Mill City Lith 01.jpg  
    "Often moments come looking for us". - Robert Frank

    "Make good art!" - Neil Gaiman

    "...the heart and mind are the true lens of the camera". - Yousuf Karsh

  6. #16

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    Ray - here is a scan of a print from a 4x5 neg, Tri-x (the 400 kind), about 15 years old, processed in HC110 B. Also used a Lt yellow filter. The neg prints beautifully on Seagull (also the old kind) G2, with small burning to the sky. The pole has detail on both the sun and shaded side, with total black on the far shaded edge and on the small shadows on the guardrail. The very lightest parts of the guardrail are pure white, providing the full range in the print.
    For me, a "perfect" neg is easiest to achieve with a clear sunny day shot. Anything from sunny to overcast requires objective judgement as to what is "perfect", as you experienced with your post above. As a result, I always test film / developer combinations on these perfect days, and go from there for other kinds of lighting.
    Attached Thumbnails Attached Thumbnails Sun, Pole & Rail.apug.jpg  

  7. #17
    Andy K's Avatar
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    I just had a quick look through my prints and here's a couple that to me were 'prefectly' exposed. The reason I say that is because both negs and prints really 'shine' (if that makes sense). But thats just my opinion)


    The landscape is Delta 100 in Rodinal 1+50. The steps are Kodak HIE in Rodinal
    Attached Thumbnails Attached Thumbnails TheThamesEstuary.jpg   1RT15.jpg  
    Last edited by Andy K; 02-23-2008 at 10:42 AM. Click to view previous post history.


    -----------My Flickr-----------
    Anáil nathrach, ortha bháis is beatha, do chéal déanaimh.

  8. #18
    MurrayMinchin's Avatar
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    Here's my example;

    http://www.apug.org/gallery/showphot...32&ppuser=4292

    The moss highlights are totally blown out, but I don't care because they add "snap & sizzle". The bottoms of the main branches print completely black, so I had to use a special mask (contrast reduction mask) to first hold that area back during the prints main exposure, then use another mask (a shadow contrast increase mask) to tease out what detail there was in the negative to put back under the branches. I could have squeezed all the tones together by using -3 development of the negative and printing on a soft paper grade, but separation in the middle values would have gone "mushy" and would have killed the mood.

    So in this case, for me anyways, what some people would call a flawed negative because of the heroics needed to print it is what I consider a perfect negative for the photograph I wanted to make.

    Murray
    _________________________________________
    Note to self: Turn your negatives into positives.

  9. #19
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    "Perfect" negatives exist only as a technical concept based on arbitrary and subjective values, or as perceived as perfect by someone for an individual printing style in a particular medium. "Perfect" really means you made a negative that prints the way you want it to, on what you want to print it on. "Perfect" in the case of negatives should be redefined to be "perfectly controlled"

    Like I said, I don't have two identical examples of hits and misses, but here are images where an exposure error in relation to my speeds and processing would have made a clear difference. These negatives were shot on J&C 100 (IRRC) rated at 64 (my tested speed for this film with PMK)Two were processed normally (my tested normal), in PMK. The third was shot and processed N+1. (N+1 means I exposed and processed the negative to "expand" it. "Expansion" or "contraction" of negatives is one of the most basic and important reasons for using The Zone System, and getting a handle on this is largely what all the testing is about. Many people who poo poo this stuff have no idea that it is possible to control tonal relationships independently from overall contrast, except with color filters. Filtering is useful, but is limited, and the most control over the process is best arrived at with a full tool box.)

    Although the development was "normal" the effective development on the first two images was N+1, meaning the highlights pulled up, but the low values remained near where they fell in the scene, because of reciprocity failure, as the exposures were long. This means the negatives were "expanded", an effect we test and plan for if we desire more separation of higher values from lower values than the scene possess. The Zone System is one of the methods that can be used to control the relationships of highlights and dark areas, not just arriving at an average exposure for a specific scene, but choosing an exposure and development to modify the relationships of the values found in that scene, beyond the natural contrast that exists within the composition with the conditions present at the time of exposure. Being able to move specific tonal values offers far more control of an image than merely adjusting the overall contrast with paper grades, or contrast filters, with the averaged contrast and tonal relationships present in a "box speed and developed" negative.

    The manufacturer has to put something on the box, and recommend some kind of development, and the numbers and recommendations that are usually arrived at are those that offer the most forgiving performance for an average situation, not the best performance for a specific situation, because it is impossible for them to predict specific situations. (one can, of course, consider forgiving performance at the expense of other factors to be paramount). The "forgiving exposure and development" is the method that you, Ray, are using and espousing, and is why you can blow an exposure, probably by a stop or more, especially with regard to over exposure, and get away with it. You aren't using all the film's capability, so there is room built in for error. What you are giving up in return for that is control of the tones within the negative, and the maximum lattitude the emulsion can deliver. A box speed and developing regimen is literally a "one size fits all approach" There is nothing inherently wrong with that, but some of us desire negatives that fit better, with the maximum lattitude the film can deliver.

    It's very much like a car. The average sedan gets ok mileage, handles ok, has a decent ride, and predictably average acceleration, because these characteristics are the compromises needed to mass produce and market the car. If that's what you want, that's what you drive. Some of us like to tinker and modify the sedan, push its perfomance to the maximum without regard to comfort or mileage, and drive it on a closed course at the absolute limit, with no margin for error. We do this because we want or need this kind of performance. Dismissing it out of hand, as you have tended to interject into exposure disscussions, is telling somebody who desires to race that they should drive a box stock sedan on race day, because the big brains in Detroit said that's how the car should be.

    In the first two examples the lighter values received more exposure in the highlights because the film was faster where the light was more plentiful. This was, as mentioned, accomplished as a side effect of reciprocity failure, but it can also be accomplished by modifying exposure and developing times, and it is mostly done that way. The ability to control tonal relationships through exposure and developing is what we test for. Had I followed box speed recommendation, and processed for this average, none of these images would exist as they are.

    If you combine the effect of the expansion of the upper zones as intended, and note where the highlights of these images fall, and also note that the highlights, and their relationship to other areas are extremely important elements of these images, its easy to imagine the havoc a one third stop error would have wreaked. There was no margin for error in these exposures, as the highlights in each are taken right to the limit. I might have gotten lucky with a WAG, instead being able to predict my results with a fair degree of accuracy, but not likely. Exposing at box speed using an incedent reading and processing according to the manufacture would have resulted in flat negatives with blown highlights, that couldn't in any case be coaxed to these kinds of light versus dark relationships without appearing very hard in contrast, or, for the last example I could have sat around on the beach at the Great Salt Lake, eating brine flies and cheetos for a few weeks, waiting for the conditions that would mimic the result of the expanded exposure and developing method, that would allow me to expose and print according to the manufacturer, to get the same result.

    If you are only using a portion of a films capability, an exposure error can be easily forgiven, and go largely unnoticed and therefore be ignored. However, if you seek to gain every bit of lattitude you can get, and take an emuslion to its absolute limit, you have to do better than a WAG, or your gonna have allot of unprintable failures. A "shoot and develop for box speed" photographer probably would have stood in the conditions where I made the waterscape negative, and said with conviction that it couldn't be made to look like I made it look.

    Here the three images that tell the same tale. The waterscape is an example of expansion by development.

    On the prints there are far more details in both the shadows and the highlights than a computer monitor can display.
    Attached Thumbnails Attached Thumbnails leaves.jpg   lamp2.jpg   gsl3.jpg  
    Last edited by JBrunner; 02-23-2008 at 02:32 PM. Click to view previous post history.

  10. #20
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    Perfect is only relative if you are trying to get some exact thing. Perfect to one might be useless to another. Old school theory is like sbandone is describing. The minimum film exposure to achieve shadow detail where you want it. Processing to achieve (according to some) 1.35 zone 8 density. Printing the minimum time to achieve total black through the film base. Changing this formula gives you different affects. Perfect is what ever you intend and then you might change your mind and perfect becomes imperfect. It is like talking about the perfect painting. If a painter believes he has achieved perfection in one of his paintings, every other painter in the world will probably disagree and instead consider the painter to be a wanker for thinking he did something perfectly which is of course impossible as is total truth.

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