Digital enlarger DeVere 504 DS

Discussion in 'Darkroom Developing and Printing' started by Claudio Bonavolta, Jan 20, 2004.

  1. Hi All,

    I've seen this enlarger which looks like a traditional printer but
    having a "transparent" LCD of 8M pixels acting like a negative:
    http://www.odyssey-sales.co.uk/products/browse.asp?range=55
    The prints are done on traditional paper either color or B/W.

    Does anyone have had the opportunity to try this enlarger ?
    What's the quality of the output ?
    Other comments ?

    Other enlargers of this type ?

    KR,
    Claudio Bonavolta
    http://www.bonavolta.ch
     
    Claudio Bonavolta, Jan 20, 2004
    #1
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  2. It never will reach quality of prints made by fine-grain films.BTW, I don't
    understand the scope of the whole idea of digital equipment, besides of the
    companies producing them making much money.
     
    Dimitris Tzortzakakis, Jan 20, 2004
    #2
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  3. Well, *I* would certainly not do this kind of assumptions ...
    Photography has some sort of technology and saying "never" in a
    technology-related field ...
    I agree with you the major scope of digital, from a company point of
    view, is making profit.
    Well, nothing new, this is the case for ALL companies, silver based
    ones included.
    I also easily understand the actual digital marketing can irritate
    more than one ...

    Let me explain why I may be interested in a digital enlarger and
    please don't start another sterile digital/analogue flame war, I will
    not answer messages going that way.

    Producing an image in a print form has three main steps:
    - picture taking
    - picture processing
    - picture printing

    Picture processing has been the first step where digital gave serious
    advantages over analogue.
    To be clear, there is nothing we can't do in analogue compared to
    digital but it is just much faster and easier (well, at least for
    people used to computers). Within the same amount of time, you can go
    further.
    This will be of a great interest for me if I can output the result in
    a satisfactory way.

    Picture taking in digital is still not completely satifactory for my
    purposes (I do mainly action shooting with 35mm).
    Some recent cameras like the D2H show that things are improving, I
    just need "some" more pixels and a better "bang for the buck" before
    my minimum requirements are fullfilled.
    Anyway, digital shooting is not for me very important, I do not need
    to obtain instantly the final image, I do process my films, color
    included, and this is fast enough for my needs.

    Picture printing is my biggest problem, I have strong concerns about
    archival aspects of the inkjet prints, I just do not trust claims of
    companies acting primarily in the micro-computer industry where the
    normal life of a product is limited to 2-4 years.
    A satisfactory solution are the actual digital enlargers like the
    Frontiers or the Lambdas printing on traditional paper but their price
    tag put them completely out of reach for the amateur.
    Sending digital files out to print on this kind of enlargers makes me
    loose control on the complete chain which I dislike greatly, after
    having done the things by my own for a quarter of a century, this
    would sound as a big step backwards.

    So, that's why I'm interested in a digital enlarger for the (serious)
    amateur.
    The DeVere is the first I saw but as I have some doubts regarding the
    technology employed (the transparent LCD acting like a neg compared to
    the laser beams of the Frontiers and Lambdas) I'd like to read
    comments from people having actually used it.
    Odyssey gives the opportunity to send a digital file, print it and
    send you back the print which I'll probably try. I hope they're
    sufficiently honest not send me a Lambda print :)

    There is no urgency in my request, but things evolve and, from time to
    time, I check if the actual technology may be of interest for my
    purposes.

    Regards,
    Claudio Bonavolta
    http://www.bonavolta.ch
     
    Claudio Bonavolta, Jan 21, 2004
    #3
  4. I would like to have an LCD-gated enlarger. But not
    for imaging the LCD.

    I think it would make just the dandiest burning/dodging/
    spot contrast/masking.... tool.

    A medium/low resolution out-of-focus (by distance or diffusion)
    LCD would illuminate the negative that creates the image
    details.

    The practical advantage I see for the Devere is production
    speed. RA4 prints can be turned out as fast as they can
    be exposed.

    The LCD enlarger is a parallel machine and should always
    be faster at exposing paper than a scanning technology
    for creating an image. The same holds for serial ink
    jet and dye sublimation technologies.

    On the cost side, RA4 paper seems to sell at parity with
    photo-grade inkjet printer. My guess is the cost of
    chemicals Vs the cost of ink is a wash.

    OTOH, I can not see any quality advantage in the
    present Devere. Not until 70 pix/mm 4x5 & 8x10
    LCD's come on line.

    However, LCD's probably follow a "Moore's Law"
    type curve: every two years the performance
    doubles and the prices halves. As an example:
    I have a 5 year old 450MHz PC I bought for
    $2000; Now a 2GHz PC costs $500 (rough figures).
    If the same holds for LCD's, who knows, the LCD
    enlarger may be the wave of the future.
     
    Nicholas O. Lindan, Jan 21, 2004
    #4
  5. I should learn: gather facts, then post.

    The DeVere flyer states: " Photo paper is accepted as the
    lowest cost, best and correct media for outputting
    digital files from any source."

    I guess it has been said before.

    300DPI on the paper is a bit marginal - looking at the
    output of 300DPI laser printers. Gonna have 'jaggies'
    with the DeVere.
     
    Nicholas O. Lindan, Jan 21, 2004
    #5
  6. Claudio Bonavolta

    Ken Hart Guest

    In response to your last question: "Other enlargers of this type?"...

    There is a device on the market called "D-Carrier", designed for use in
    older mini-lab printers.
    Basically, the unit is placed in the negative stage instead of a negative.
    Quoting from the Minilab Supply Store catolog: "The D-Carrier is installed
    when printing from digital files. Switching between D-Carrier and
    conventional 35mm carrier takes only seconds. It can be installed on most
    conventional minilabs. It is already available for Noritsu, Gretag, Konica,
    Fuji, and Agfa photo equipment models. Image resolution for 8"x10" photo:
    245dpi, 4"X6" 450 dpi."
    No price is given, except "as low as $440/month"; I assume that that means
    for the rest of your life!

    Ken Hart
     
    Ken Hart, Jan 21, 2004
    #6
  7. We're not sure where you're getting the figure of 300DPI, but since the
    DeVere 504DS is not a printer but an actual enlarger, projecting an image
    through a traditional enlarging lens onto conventional photographic paper,
    DPI is not applicable. As a North American representative for DeVere, we
    have a number of 16x20 prints made with the DeVere 504DS and can assure you
    that the prints exhibit no "jaggies." We can also assure Claudio that there
    would be no point in substituting a print made on a Lambda, as, from
    everything we've seen, the prints made on the DeVere are superior.

    But don't take our word for it - we invite you to submit a digital image
    file of your own and have a sample enlargement made. Compare it to the
    output from any other digital image printer. Regrettably, there aren't yet
    any demo machines in North America, but we'd be happy to forward your file
    to the factory in England for printing. Our website is at
    www.khbphotografix.com and our DeVere Enlarger Guide website is at
    www.khbphotografix.com/devere/
     
    KHB Photografix, Jan 22, 2004
    #7
  8. I don't want to get into a discussion purely about semantics, but as you
    pointed out, DPI is a printer term, and strictly speaking is not applicable
    because there is no printhead involved with the DeVere. The factory used
    poor judgement in using DPI in their brochure, but were attempting, I
    suppose, to use terminology that would sound familiar. If a term of
    resolution must be used, then pixels per inch would be more appropriate.

    Etching the LCD panel's glass would "blend" the pixels, but would not result
    in satisfactory image quality. It would, in fact degrade the image. The
    DeVere 504DS uses cutting-edge software controlled piezo movement of the LCD
    panel with selective multiple exposures to enhance the image. With this
    technology, the apparent resolution is increased and "jaggies" eliminated.

    You have not yet viewed prints made with the DeVere, so if you doubt the
    effectiveness of the system, once again we invite you to submit your own
    digital image file and examine the prints.
     
    KHB Photografix, Jan 22, 2004
    #8
  9. Sorry, my fault, I wrote "printer" but I meant enlarger as the 504 DS
    is absolutely a traditional enlarger except for the "negative" stage.
     
    Claudio Bonavolta, Jan 22, 2004
    #9
  10. The advert for the enlarger:

    http://www.khbphotografix.com/devere/Current/504DS.htm

    states 8 megapixels.

    If an 8x10 print is made then:

    8 megapix => 8Mpix /(8"x10") = 100Kpix/in^2 => 316 pix/in on the print.
    It's got pixels. Each pixel makes a dot. The paper's got
    inches. The result is dots/inch - DPI.

    Put them through a lens, enlarge them, print them on RA4, it's
    still dots/inch.
    I do not doubt you. But that may be because the optics
    and paper are not up to the task of making a sharp image
    of the pixels. Most likely though, is that the LCD's glass
    is slightly etched so as to 'blend' the pixels.

    The 'jaggies' term comes from the old days of laser printers,
    where nice square 300 dpi pixels were put on the paper. A straight
    line at an angle exhibited little jags along its length.
     
    Nicholas O. Lindan, Jan 22, 2004
    #10
  11. Claudio Bonavolta

    Jorge Omar Guest

    That's the sour test of any printer - do a diagonal line.
    316 dpi translates to 6.22 lp/mm - the bare minimum for quality photos.
    Any larger enlargement will be below this minimum.

    And the math is right. No matter which 'tricks' one can play.

    Jorge
     
    Jorge Omar, Jan 22, 2004
    #11
  12. The DeVere 504DS is a unique application, but piezo movement technology is
    being used in digital camera backs to allow a relatively small CCD to create
    a large high resolution image file. If you do a Google search on "digital
    camera piezo movement" you'll find quite a lot of information.
     
    KHB Photografix, Jan 23, 2004
    #12
  13. Claudio Bonavolta

    Jorge Omar Guest

    Well, here we have something unusual.

    Jorge
     
    Jorge Omar, Jan 23, 2004
    #13
  14. ObWarning: this is mostly argument and rant for the sake of
    argument and rant: early stage primate posturing. Neither
    of us has anything enlightening to say about much of anything.
    As qualification, I've been involved in computer graphics since the
    70's: Started out on an Evans & Sutherland LDS (III ?, it had a
    shader), worked for Gould's Graphic Products Division, developed
    electronic systems for pre-press graphics, and work now with
    one of my clients on image analysis systems for the evaluation
    of print quality. So what.

    Pixels and dots are variations of a theme. They are both the discrete
    elements that make up a picture. Pixel comes from Pict(ure) + el(ement),
    and they were called 'pictels' at one time. Pix/dots are referred to as
    pixels if they glow (LCD, CRT, light gate...) and dots if they don't.
    Pixel implies that the element's value (RGB) can be changed -
    when the image element is on the paper it is expected to
    maintain its value (CMYK) and is, generally, no longer referred to
    as a pixel but as a dot. Big deal.

    So you have pixels on the LCD panel and dots on the paper. Like
    anybody cares.

    You like pix/inch -- fine, no argument here. But don't be
    surprised, or offended, if the word 'dots' is bandied about.
    "Dots" doesn't imply a dot-matrix printer anymore, the under
    30's don't even know what a dot-matrix printer is except as
    a story told by Gramps. Oh, lord, won't this ever stop.
    Blur the image, maybe? That's what happens when my enlarger vibrates. Or
    if I move it between exposures.
    "Apparent" is the operative word. What about MTF? But that's getting
    pedantic.
    Right. We agree.

    I think the Devere solution is very elegant, I like it.

    A bit of blur is better than jaggies (er, you may prefer
    the word 'pixelation') or moire patterns any day (that's
    'low frequency modulation by superposition of periodic
    quantization').

    I am sorry if talk of such crudities as "dots", "jaggies" and
    "fuzzies" has offended you. I am an engineer, not a marketeer,
    and you know how engineers are - the sort of bloody literal
    minded folks who created your enlarger in the first place.
    And familiarity with technology does bring along a fine
    contempt for the stuff.

    You might want to drop "cutting/leading-edge" though,
    the "cutting-edge" of technology is more often the "bleeding-edge"
    of the balance sheet. The folks with the money bags like "mature, proven
    technology" these days. Especially if it is also "sophisticated
    technology". Wing tips, not Birkenstocks.

    And "cutting-edge software" brings up visions of Bill's Blue Screen
    of Death - Retry, Abort or Ignore?
    Wouldn't happen to know if your engineers tried etched glass before
    they resorted to buzzing the panel, er, moving the panel with cutting
    edge software controlled peizo thingies.

    As to your offer of a print, I am sure it would be a lovely print,
    no doubts.

    I am not doubting the enlargers performance. It all started with my
    observation that 300 dpi on the paper was a bit low if the d's were
    sharply imaged. I postulated a "mature, proven technology" to correct
    the problem and you corrected me and pointed out the technology was
    "cutting edge". Of course, if someone gets it to work with etched
    glass they will have a hell of a cost advantage ... hey, off the
    lab I go.
     
    Nicholas O. Lindan, Jan 23, 2004
    #14
  15. Claudio Bonavolta

    David Strip Guest

    You appear to be assuming that as the LCD is shifted, the image is constant, and
    that the resulting printed image is just a blurred image of the LCD. While I have
    no idea what DeVere is doing, other systems have been built around this concept in
    which the LCD is stepped to discrete positions and a different image is projected
    in each position. Since LCD's often have a fill factor of ~25%, you can image 4
    distinct pixels/dots by moving the LCD to four distinct positions. The resolution
    is not increased "apparently", it's increased for real, assuming the imaging
    optics aren't the limiting factor. The MTF is increased, though I don't pretend to
    understand enought optics to know if it's a factor of 2 or what.
     
    David Strip, Jan 23, 2004
    #15
  16. No, I wasn't, though I may have given that impression with references to 'etched
    glass' and 'vibrating enlargers' producing much the same effect. I was referring
    to elimination of the jaggies caused by imaging sharply defined pixels at 300 DPI.

    To achieve a smooth gradation between pixels you would, of course, have to print
    at intermediate pixel intensities at intermediate positions to achieve a smooth
    gradation between pixels. DeVere clearly states that this is what they are doing:
    Lots of discrete exposures at different display intensities with a filter and
    each exposure really being three exposures, one through each of the positions
    on the filter wheel.

    The same effect, though, can be achieved by with a motion that varies velocity
    with position, much the same as burning a print: the burning hole spends a lot
    of time in the middle and less and less time as it is moved farther from the
    circle.
    Agreed, if an LCD has less than a 100% fill factor then a step and repeat
    puts down a higher resolution image with more information. The net effect
    is to create virtual pixels. Think of it as 100% fill.
    I wouldn't say it is increased. The pixel size is the same, and so the
    minimum feature size is the same. It is just that without motion 3/4 of
    the pixels are missing.

    So, lets theorize a system with pixels with a 100% fill factor, as that
    is what has been accomplished by DeVere.

    Now we are now where we have started ... 300 sharply defined spots/inch on
    the paper.

    And the problem is how to blend the boundaries between the spots/dots/pix
    to make the whole pleasing to the eye.

    To do this one can move the screen in a smoothly in a 2-D Gaussian manner
    (shudder), approximate same with discrete exposures, or approximate the same
    by utilizing an optical system that produces a Gaussian blur of just the right
    sort.

    My guess was they already had the step and repeat action just to achieve
    pixel fill. And frosted glass or a coke-bottle lens just didn't cut it,
    so the solution was extra exposures at intermediate pixel positions.

    Now, back to this idea that moving (packed) pixels around will create
    resolution that is greater than achieved by stationary pixels.

    I propose the following experiment:

    Use a 1 pixel system in one dimension as the machine/printer/enlarger/
    latest-term-thought-up-by-marketing. And further simplify the system
    by constraining the pixel to horizontal moves - sort of like moving to
    "Lineland" from "Flatland". If it works for one pixel and one dimension
    it should be generalizable to many pixels in 2 dimensions.

    This one pixel can print any shade from white to grey in an additive
    manner: 2 white exposures = white, 1 white + 1 grey = grey, 2 grey
    exposures = black ...

    It is, obviously, possible to make a black one pix spot next to a white one
    pix spot. A repeating pattern of white/black pixels is your basic MTF input,
    though really one should use a sinus density profile a square wave profile
    works about as well.

    Now, with multiple exposures, is it possible to make a periodic image that is of a
    higher frequency than that above? I.E.: one where the distance from the center
    of one black area to the center of the next black area is less than two pixels.

    If we allow the pixel to print with opaque ink then black and white then it is
    easy to see that zebra patterns of any frequency can be made can be made.
    But only at integer multiples of the base frequency. One leading cycle,
    starting from a blank stretch, can be made at any frequency, but the pixels
    will make a mess of the image to the right (assuming the pixel moves left to right)
    so that an arbitrary frequency can not be repeated smoothly. The ability to image
    frequency multiples is the same effect as size of the lens's bokeh (the size
    of the pixel) causing apparent lens resolution in an MTF test to suddenly
    spring to life again after having dissolved into pure grey.

    The ability to image at discrete frequencies is called an artifact. Rather
    than producing more detail it produces moire patterns in the output.

    The moving pixel problem is a variation on 'box car averaging' filtering, a well known
    technique in digital signal processing. It produces a low-pass filter with
    a comb-like pass band after the first filter zero. The mathematical literature
    for box car functions is hundreds of years old.

    Just search for 'box car filter' with google.

    In summation the effect of moving pixels around is a blur, no increase in
    information transfer is possible.

    Sorry, no free lunch.

    And again, there is nothing new under the Sun but that thinking makes it so.
     
    Nicholas O. Lindan, Jan 23, 2004
    #16
  17. Claudio Bonavolta

    jjs Guest

    The proof is in the printing.
    Be nice and share.
    I look forward to receiving my complimentary DeVere 504DS.
    When's it arriving?
     
    jjs, Jan 23, 2004
    #17
  18. The basic technology is from MuellerSOHN, DeVere is incorporating
    it into its own product, as are several firms in the
    photolab business.

    http://www.muellersohn.de/LCD_E.html

    Looks like the digital LCD mini-lab printer is on its way to
    a drug-store near you.

    And the name of the game here is _speed_. Resolution
    only has to be consumer grade.

    On another front, Intel has developed high resolution
    LCOS (Liquid Crystal On Silicon), slated initially for
    projection TV, but going who knows where.... a minilab
    near you, maybe.

    http://www.reed-electronics.com/electronicnews/article/CA373668?text=intel
     
    Nicholas O. Lindan, Jan 23, 2004
    #18
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