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06-22-2018, 08:45 PM - 1 Like   #1
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don't use an iPad as a light box

I've seen a bunch blog articles and other websites recommend using an iPad as a light box for digitizing film. Well, I'm here to tell you that unless you have some kind of diffuser between the iPad and your negative, you will very likely see the grid of iPad pixels. maybe there is a way to make it work that I'm missing?

(the pixels should be pretty noticeable if you zoom in, but they were even more noticeable, before I reduced the image size.)

EDIT: added a 1:1 zoom crop

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06-22-2018, 08:51 PM   #2
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I see the grid, would perhaps putting down a sheet of grease paper diffuse the individual cells?
06-22-2018, 08:58 PM   #3
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Maybe, I think the trick would be it needs to be consistent. grains in the paper, differences in opacity, would all show.

I have a pentax bellows and slide copier that I use for digitizing 35mm, and it has worked great once I figured it out. I'm still trying to figure out a good setup for digitizing medium format (6x4.5 and 6x7) I figured it was worth a shot. I've never used Kickstarter, but I'm tempted to support this thing:

pixl-latr - helping you digitise 35mm, 120 & 4x5 film by Hamish Gill ? Kickstarter

since it includes the diffuser and holds the film flat against the diffuser. The the iPad would work as a illuminator behind it.
06-22-2018, 09:23 PM   #4
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Yup. Been there. Dealt with that. I tried lots of DIY solutions and in the end bought one.
I use this one - it's gone up a tad in price , but it works prefectly for this (your) purpose here, and you can power it from a USB cable from an AC adapter or simply plugged into a computer which is ridiculously useful since you'll obviously have a computer right there.

amazon.com: Litup A3 Light Box L18.86W14.21 Inch Light Pad Light Table Drawing Light Board for Artcraft Tracing Animation Stencil-LP3-USB(A3-USB): Electronics?tag=pentaxforums-20&

---------- Post added 06-22-18 at 09:24 PM ----------

QuoteOriginally posted by bertwert Quote
I see the grid, would perhaps putting down a sheet of grease paper diffuse the individual cells?
That works to an extent but the iPad just doesn't get quite bright enough after it's diffused to really get enough light through dense negs or slides.

06-22-2018, 10:31 PM   #5
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I tried Kindle Fire with app. Effect was even more noticeable. Bought light table after that.
This one costs only $24. https://www.amazon.com/ME456-Light-Ultra-thin-Power-Tracing/dp/B01EBA8ZX8/re...13367323&psc=1
Works just fine for me.

Last edited by jumbleview; 06-23-2018 at 06:24 AM. Reason: Added link to light box
06-23-2018, 12:10 AM   #6
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...ouch!
Perhaps that DIY crowd didn't have an eye as good, or "good enough" was enough for them?
06-23-2018, 12:39 AM   #7
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There are some LED light pads on eBay for around 10 / $15, you just have to be careful that they're not the type with an Aluminium grid as they're even worse than using a tablet.
Image below is a comparison between the two types taken from a listing on ebay.co.uk

06-23-2018, 12:57 AM   #8
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QuoteOriginally posted by LensBeginner Quote
...ouch!
Perhaps that DIY crowd didn't have an eye as good, or "good enough" was enough for them?
True story, but you're right on both counts. It really is *good enough*, especially for web-posting size in most cases. But transparencies are even worse usually.
And I just figured, you're going through the trouble of setting up DSLR scanning already which is finicky to get dialed in at first...
so you may as well have a good light source. But yeah, nothing really wrong with DIY. The whole operation, even with a light table is still pretty much DIY.

06-23-2018, 01:02 AM - 1 Like   #9
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QuoteOriginally posted by chickentender Quote
True story, but you're right on both counts. It really is *good enough*, especially for web-posting size in most cases. But transparencies are even worse usually.
And I just figured, you're going through the trouble of setting up DSLR scanning already which is finicky to get dialed in at first...
so you may as well have a good light source. But yeah, nothing really wrong with DIY. The whole operation, even with a light table is still pretty much DIY.
No nothing wrong with DIY at all, but DIY done-properly (I guess we could call it DIYDP? )
06-23-2018, 05:27 AM - 1 Like   #10
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A couple of ideas:

1) Use a wider aperture so the iPad pixels are out of focus.

2) Put a plate of glass on the iPad to move the pixels further from the film plane.
06-23-2018, 06:12 AM   #11
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QuoteOriginally posted by photoptimist Quote
A couple of ideas:

1) Use a wider aperture so the iPad pixels are out of focus.

2) Put a plate of glass on the iPad to move the pixels further from the film plane.
yeah, I thought about spacing the film away from the iPad, but I didn't have anything to make it work well. That image was shot at ƒ8, the lens can go down to ƒ2.8 (Pentax F 100mm 2.8 Macro), but then I start worrying about getting the film perfectly parallel to the sensor (this isn't being done on a copy stand, just a tripod and a table.) Eventually, I get to the point of wanting to spend a little more to not have to worry about a hack job.
06-29-2018, 01:28 AM   #12
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The easy solution is to use sheet of glass which at macro levels is enough to blur the pixels. For DSLR scanning I used two sheets of glass anyway to keep the film flat. Best to hold it with books or something so you have more space under and can easily slide in or adjust the phone/tablet underneath. Then there's the question of good color reproduction for color films and that's harder to evaluate. The cheap LED or backlight sources will always have lower color accuracy and incomplete spectrum as they optimize the brightness and electricity to light conversion efficacy rather than good color reproduction.
08-07-2018, 02:12 PM   #13
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I recently had an epiphany. I was trying to hack a method to hold the film flat and away from the iPad, and was banging my head against the issue. 35mm was solved because I have a Pentax bellows with slide copier, but my medium format was suffering. I seriously considered buying a used Pentax 67 bellows with its 6x7 slide copier, and a 67 to K mount adapter, but that setup is VERY expensive.

Then I realized--I have an enlarger that I'm trying to get setup to do wet prints. That enlarger has a bunch of negative holders (at the moment, 4x5, 6x7, 6x6, 6x4.5, 35mm, and one with a small square opening, I'm guessing for 126 film, but I don't know.) It turns out that these are perfect for holding the negatives flat (go figure), and the thickness of the bottom plate is sufficient that I don't see any grid when shooting at 8. So now I'll use those negative carriers for digitizing and for enlarging. And if you happen to need something similar, some of the negative carriers cam be had pretty cheap.

This dark shot would be one of the worst if the grid was visible because all that black would have been transparent:

08-08-2018, 12:40 AM   #14
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Jeez.... it might be cheap in the states but when I looked at the same item on Amazon UK, it cost 87 which is $112
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