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  1. #1

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    Computer as support in the darkroom

    Hello Forum,

    After I’ve been lurking for some time now and have learnt a lot here, I’ve finally decided it’s about time for my first post.
    I’ve (re-)started with analogue photography about 8 months ago, for 4 months now with an own provisional darkroom in the garage. I started using the f-stop method for calculating my exposures times from the start and experiment a lot with manual split grade printing. “Way beyond monochrome” helped me a lot with everything!
    However if I don’t concentrate really hard all the time, a lot of careless mistakes like forgetting to set the proper time, use the right filter, etc. still happen. So I thought about using the old computer that is in the darkroom anyway (for Music, Forums, eBooks, etc.) to support my personal workflow. At least until I can afford one of the great RHD stopclocks or similar devices. BTW, I use a sheet of Lee Blood Red 789 gel in front of the 22’’ screen and it gives zero fogging after 15 minutes, 20 centimeters away from the monitor on MCC 110 and MG IV RC.

    As I wanted to learn how to code anyway, I’ve started to develop a little C# program. Below you can see what the program can do at the moment.

    The hardware to switch the enlarger on and off had to be really simple. So I chose this one:
    http://www.robot-electronics.co.uk/h..._rly02tech.htm
    As this board has 2 relays, it can switch off the safelight while the enlarger is turned on and vice versa. All I had to do, was to screw in 3 wires from a double extension lead. That was great, as I have no idea how to solder.

    So here’s what the software can do until now:

    For enlarging:
    - Turn the focus light and the safelight on and off, (Hotkey ESC)
    - Control the enlarger with the Timerbutton (Hotkey Space)
    - Turn off monitor for exposure metering (Hotkey B)
    - Large countdown display
    - A metronome with 1 sec ticks during the exposure
    - Teststrip programme using the F-Stop method
    - Differentiate between „local“ test strips and „classic“ test strips across the picture
    - Printing program with stored sequence of burn ins, including the usage of split grade method
    - Application of a Dry Down factor for the final printing program
    - „Quick Note“ function on F1 – F12 to access and store general information E.g. I’ve stored the filter settings for all grades on the Durst M605 under F1

    During paper development:
    - A Countdown, (that also runs in the background) with alarm function to indicate that the paper has to change the station
    - The sequence and times can be configured freely
    - Possibility to store sequenceds and times for various paper types in the backend database

    To keep documentation:
    - All data for a picture can be stored in the backend database (MS SQL Express). With that data, the printing program sequence is stored as well.
    - Possibility to store scans of the contact sheet, the printing map and the final picture in the database

    In general my workflow with the program is something like this:
    First I find the base exposures for the soft and hard grade with the test strip program. The exposures are stored in the respective fields of the printing program via right clicking it. Then I set the burn in sequence for soft and hard grade with a good description. After hitting the “start program” button, the timer button is loaded with the values in the right sequence. After hitting the timer button, the next value is automatically loaded and the status bar gives me the comment, telling me what has to be done at the current step. When the printing program is finished, the paper development timer screen starts and helps me keeping the appropriate times for each station. When the print is finished, I save all settings and data into the database. When I use the data next time e.g. with another paper type or another enlarging factor, all I have to do is find the right base exposures. The f stop calculation takes care of the rest.

    I wanted to include some kind of exposure meter as I have seen in the trialux as well. As I don’t understand how to code, and know even less about electronics, I am a little stuck here. Does anyone here know of a light sensor that can be used for this kind of thing, that comes with a USB connector to read in the values to the computer? Has to be really cheap though I will only start to think about the logic (what to do with the values) once I have an idea if it’s possible to get them into the PC anyway.

    Let me know what you think. Any comments helping with the exposure metering would be greatly appreciated as well.

    Thanks, Josh
    Attached Thumbnails Attached Thumbnails EnlargerScreen.jpg   DevelopTimerScreen.jpg   PictureDetailsScreen.jpg  

  2. #2

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    That souns very complicated to me unnecessarily so. I have used the computer to aid my colour printing. I make a smallish print say 5x7 and use the colour balance given on the digital print as an aid to getting the right colour balance on a 'proper' print. Even that was a hassle so gave it up.

  3. #3
    Ian Grant's Avatar
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    I think it needs evaluation.

    I used to use Access as a database for all my info back when it came out and had a really good system, then Microsoft updated Access, no big deal but totally obsolete at the next upgrade. Since then I've reverted to memory and I can reprint from negatives made over 25 yeras ago without a problem.

    The key for me are the timing parts, I do use a program at the moment for film processing, O'm not sure I'd fully use something like this but others might.

    Ian

  4. #4

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    Thanks for your feedback. I may very well have a tendency to overcomplicate things. Leave aside the paper development timer (which is more or less just a stop watch with preset intervals) and the storing of the picture data into a database instead of a manual documentation on paper (including the 3 scans).
    The test strip / printing part basically just automates f-stop calculation, note taking, writing down the printing sequence and setting the times for the enlarger. I've done this on paper before and quite often made careless mistakes like forgetting a step in the sequence or setting the wrong time etc. With the program you'd still have to do all the thinking - meaning you decide on the sequence and times yourself.

    So this means my approach tin general is too complicated? What I do (no matter if manually or with the program):

    Splitgrade:
    1. Find the correct soft grade base exposure using the f-stop timing method via test strips
    2. Find the correct hard grade base exposure using the f-stop timing method via a second set of test strips
    3. Decide the print plan for soft and for hard grade separately. Note this in F-stops from base exposure
    4. Execute the print plan

    When I do normal Printing, I do:
    1. Find the correct base exposure using the f-stop timing method via test strips
    2. Find the correct contrast grade with a second set of test strips
    3. Decide the print plan (again with soft and for hard grade separately). Note this in F-stops from base exposure
    4. Execute the print plan

    Please bear in mind I am a total beginner. So if this can be done much easier and faster, any comments are highly appreciated.

    Thanks, Josh

  5. #5

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    Oh and just in case the question comes up: This is not meant to go commercial and was purely intended to be used for myself to help me cut paper waste and time in the darkroom and still get at least some results per session. With 3 young kids it is generous enough from my significant other to get at least 4 days a month off.. BTW, it also gives me the chance to occupy myself with my new hobby while being away from the darkroom. Most of the stuff was coded on the bus while commuting to work.

    Still if someone is interested in that stuff (or even likes to participate), I'd very much like to share what I have so far. Maybe this could also inspire others to come up with a better program (I'm just learning how to code!). In the end you could get at least an f stop timer that way for as low as 35 Euro - that's the price of the relay board.

  6. #6
    cliveh's Avatar
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    Very good, but does it have an intuitive human approach to the image?

    “The contemplation of things as they are, without error or confusion, without substitution or imposture, is in itself a nobler thing than a whole harvest of invention”

    Francis Bacon

  7. #7

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    Quote Originally Posted by cliveh View Post
    Very good, but does it have an intuitive human approach to the image?
    No, but neither does any other stop clock AFAIK. Or to quote myself from the post above: "With the program you'd still have to do all the thinking - meaning you decide on the sequence and times yourself."

  8. #8
    Ian Grant's Avatar
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    For the first time in over 40 years I'm without a darkroom, short term hopefully I've just about sold my house. However a new temporary darkroom is awaiting space to be freed up by other family members. I'd be willing to try the system out.

    Ian

  9. #9

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    I used to use f-stop printing - I calculated the times once and wrote them down on a piece of paper - starting at 1 sec and going up further than I'd ever need to use in practice. Then I just read the times off the paper.
    I don't worry about forgetting to set the timer because I use use the method described in Ansel Adam's book "The Print". I have a metronome timer set to its max time. I control exposure with a black card and by counting metronome ticks. My sequence is:
    1) Put the card under the enlarger lens and turn on the timer.
    2) Count off 10 ticks (10 sec) to allow the enlarger light time to come up to full power.
    3) remove the card and count ticks of the metronome to expose.
    4) put the card back under the lens to stop exposure, then turn off the timer/light.

    This should give you more consistent exposures as the enlarger light doesn't turn on and off instantly - there is a short period of time while the light warms up/cools down where the light output is variable.

    I stopped using F-stop printing because I found it wasn't really worth the effort. It didn't really save me much paper, because after a while of printing, you get to the point where you can look at the negative and get a pretty good estimate of what the exposure should be. Given that, I generally don't need more that one ( or 2 for splitgrade ) test strips. What really uses up the paper for me is coming up with all the dodges and burns necessary to turn your work print into a final fine art print.

    Color printing is another whole ball of wax. There I go through a lot of paper trying to get the color balance right. One way I've found to reduce the amount of paper consumption is to use small pieces of paper in important areas to get correct color balance/ exposure. For example, if I have a photo with a person in it, I'll tear an 8x10 sheet of paper into 4 4x5 sheets, put the 4x5 sheet where the person't face is, and use that to get the color balance right - this gets me 4 adjustments per 8x10 sheet instead of 1.
    Emancipate yourselves from mental slavery;None but ourselves can free our minds. - Bob Marley

  10. #10
    cliveh's Avatar
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    Quote Originally Posted by jseidl View Post
    No, but neither does any other stop clock AFAIK. Or to quote myself from the post above: "With the program you'd still have to do all the thinking - meaning you decide on the sequence and times yourself."
    You decide yourself. What an innovative idea.

    “The contemplation of things as they are, without error or confusion, without substitution or imposture, is in itself a nobler thing than a whole harvest of invention”

    Francis Bacon

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