iPad enlarger

Discussion in 'Misc. Hybrid Discussions' started by RalphLambrecht, Jan 30, 2018.

  1. OP
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    RalphLambrecht

    RalphLambrecht Subscriber

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    what is the least sensitive paper on the market today?
     
  2. Frank53

    Frank53 Subscriber

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    I remember I had to expose Foma Warmtone rc 4 or 5 times longer than I did MGIV.
    Regards,
    Frank
     
  3. etn

    etn Subscriber

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    This is interesting. I was expecting the RGB structure of the pixels to show on the print: our eyes react in a certain way, but photo paper certainly reacts in a different way.

    Are you doing this in black&white or color?
     
  4. etn

    etn Subscriber

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    This would be an idea for an iPad app:
    - load a picture
    - compute the negative
    - switch off the screen AND the backlight (this can be controlled by software)
    - expose the paper
    - switch off the screen AND backlight again

    Icing on the cake, several functions could be thought of:
    contrast variation by modifying the "color" of the negative, "remote" triggering e.g. by listening to the microphone - clapping hands would start the exposure, etc.

    Are there iOS programmers on Photrio?
     
  5. Craig

    Craig Subscriber

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    The two biggest barriers to innovation are:
    "we've always done it this way"
    "We've never done it that way"
     
  6. Mr Bill

    Mr Bill Member

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    Well, there is a gap between the imaging surface and the photo paper. I don't have an iPad, but did measure this distance (optically) on my smartphone - about 1.1 mm (0.045 inch) - roughly the thickness of 4 or 5 business cards. I would imagine that this is well enough to blur out the colored pixels, which on my phone (not a high end unit) are on the order of ten times smaller. The iPad may have a smaller offset distance, I dunno, but most likely smaller pixels along with it.

    Regarding the effect of colored pixels carried over to the paper, I once prototyped some gear using an image from a color CRT monitor to combine some graphics with an image on color paper. It was "acceptable" for this, even though the colored pixels were clearly seen under magnification. I doubt it would have been ok for, say, skin tone reproduction, but I dunno; this was not our purpose (we didn't use the system for other reasons, so didn't shake out details). I would just say that "quality" always pertains to what one's purpose is.
     
  7. David A. Goldfarb

    David A. Goldfarb Moderator Staff Member Moderator

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    I'd be concerned about the screen backlighting interfering with the exposure--that's the issue of the "black" screen emitting light, but the backlighting is also on during the exposure.
     
  8. NedL

    NedL Subscriber

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    David beat me to it. I don't have an i-pad but I'd be surprised if the screen doesn't have a backlight. If it can't be turned off, then you're going to want to go for short bright exposures, so that the backlight is a small proportion of the total.

    Edit: of course the backlight must be on during the exposure, or there would be no image.
     
    Last edited: Feb 2, 2018
  9. Mainecoonmaniac

    Mainecoonmaniac Subscriber

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    Here's an expensive version of digital enlarging.

    http://de-vere.com/products-504ds-digital-enlarger/

    But for me, I have some images shot on a digital camera which I'd like to print on silver gelatin paper. The only half way decent that I've tried is doing digital negs with OHP film then contact printing it. The quality is not great, but acceptable. Maybe an Ipad Mini with a Retina screen used on by Beseler 45MXT enlarger will work.
     
  10. MattKing

    MattKing Subscriber

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    Around our way, Costco uses Fuji colour photographic paper to print from digital files. If I want a 16x20, it costs the unbelievably low amount of $8.99 to get one done there. The quality seems good, the service is incredibly fast, and there usually is someone knowledgeable to talk to. They are also happy to re-do prints that are unsatisfactory.
    They also provide colour profiles for their printers for those who prefer to work in a fully colour managed system. And you can elect to have work done without any colour correction.
    They bought new machines for all of their local sites a couple of years ago, and seem to be doing a lot of business.
     
    Last edited: Feb 2, 2018
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    RalphLambrecht

    RalphLambrecht Subscriber

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    there are nodiscernable screen pixels showing on the print but the, they are so easily overexposed that that fine detail may be lost.
     
  12. Luckless

    Luckless Member

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    I would imagine that the glass gives just enough spacing between the paper and pixel elements to blur the individual sub-pixels out enough to be a non-issue with the higher res screens.

    Rather than trying to write an app or something to wake or sleep the screen, what about putting a black card between the iPad (that is on) over your paper, readying the image on your iPad, lay it in a custom frame to hold alignment, pull the card out quickly, then use the power button to sleep the device at end of your exposure time?

    Also don't forget to run airplane mode and double check you don't have any apps that could trigger and local notifications. - You might get a nice image recording you have a new email, or something to collect/harvest somewhere. :tongue:
     
  13. ic-racer

    ic-racer Member

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    The bandwidth of my iPad screen is 1:1024, which is a ten stop difference between the 'black' screen and white. You don't want to decrease this at all by lowering the backlight intensity, otherwise the 'black' screen might fog the paper. Use neutral density to control exposure. Rosco ND; a few dollars a sheet.
     
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    RalphLambrecht

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    I figure, the solution could be in preparing the image in PS first. I can dim the image there and apply a color cast to compensate for the blue-rich light of the iPad screen.
     
  16. klownshed

    klownshed Member

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    If you go into settings -> Display & Brightness -> Night shift, you can make the display warmer. Tap the manual button and adjust the slider and you can change the whites from quite blue to horribly yellow and pretty much anything in between.
     
  17. klownshed

    klownshed Member

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    If you go into settings -> Display & Brightness -> Night shift, you can make the display warmer. Tap the manual button and adjust the slider and you can change the whites from quite blue to horribly yellow and pretty much anything in between.
     
  18. klownshed

    klownshed Member

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    If you go into settings -> Display & Brightness -> Night shift, you can make the display warmer. Tap the manual button and adjust the slider and you can change the whites from quite blue to horribly yellow and pretty much anything in between.
     
  19. Eric Rose

    Eric Rose Subscriber

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    I'd be interested in seeing your results Ralph.
     
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    RalphLambrecht

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    that doesn't seem to be enough; I have to alter the image in PS before importing into the iPad to get what I need.
     
  21. John51

    John51 Member

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    Probably a pita to use: A large diy box camera. ipad at one end and a pinhole at the other. I doubt there would be complaints about over exposure. :smile:
     
  22. NedL

    NedL Subscriber

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    That's a pretty neat idea. The pinhole would be exactly 1/2 way between the ipad and the photopaper ( for 1:1 ) and if it was on the order of a pixel size, it would not limit resolution, at least geometrically.
     
  23. sepiareverb

    sepiareverb Subscriber

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    The Seagull warm tone is pretty slow, and there is the ADOX Lupex still available I believe. I have about a half a box of the FOMALUX contact paper here if you want it just cover shipping.
     
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    RalphLambrecht

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    this idea is definitely worthy of consideration.
     
  25. OP
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    RalphLambrecht

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    I like take you up on that.what size and can pay you via PayPal?
     
  26. sepiareverb

    sepiareverb Subscriber

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    Will message you Ralph.