• Welcome to Photrio!
    Registration is fast and free. Join today to unlock search, see fewer ads, and access all forum features.
    Click here to sign up

Computer monitor as direct "negative?"

Rainy Day Trees

A
Rainy Day Trees

  • 6
  • 1
  • 88
One Way

A
One Way

  • 3
  • 1
  • 87

Recent Classifieds

Forum statistics

Threads
203,156
Messages
2,850,709
Members
101,704
Latest member
yppnq
Recent bookmarks
0

Paul Verizzo

Member
Joined
Jan 20, 2008
Messages
1,648
Location
Round Rock, TX
Format
35mm
Yeah, I would probably laugh, too. But hear me out. I am either onto something or, despite 68 years of photography and much of that darkroom experience, missing something big that would negate my whole idea.

I sold my enlarger before my big move three years ago. At the time, I had started thinking about digital negatives. The idea of being able to perfect a negative sounded better than always adjusting paper contrast and experimenting with exposure times. But just reading about it sounded WAY more complex that going straight traditional.

So recently I was staring at my computer (as I do way too much) and I realized that it is a perfectly illuminated flat light source! And then......................I realized I don't need a digital negative, I can use the image straight out of a photo program.

I've long loved how I can take scanned prints or negatives and in a few slider moments, make them contrast perfect, full range. And adjust the levels curve, even, make the midrange pop. Can't do that with conventional print making.

My thinking is, lay a monitor on its back, devise whatever paper holding device that would be helpful, expose and develop. No production of a negative, no worrying about printers, inks, substrates. No need to store the negatives. Tweaking done in seconds, re-expose, print again.

I notice that the typical image on screen is way too bright compared to an enlarger source, or even an old fashioned contact printer. (I'm thinking conventional paper, no alternative processes. Yet.) The too bright image is easily corrected by darkening the entire "negative." In fact, using the computer I can adjust and manipulate any source image as I wish, using black/white points, gamma, or curves! Would also be good for Rockland emulsions, of course. (BTW, I see Foma has one much, much cheaper.)

My 23"? 4:3 monitor can easily handle 11x14, the size of my trays. The old, unfashionable 4:3 monitors are better, I think. More like a typical photo format. Wide screen is for movies, not photography! My not so humble opinion.

I included a ten sheet package of Ilford MG 11x14 paper in my last Freestyle order. Although I hope to eventually print on more interesting papers, MG RC ones are the cheapest. Regardless of the spectrum of my monitor, I can adjust to fit the raw paper easily. No filters needed.

Will be a few weeks before I can test my theory. In the meantime, any thoughts? What have I missed that blows this up? Will the LED pixels be apparent? Can't be any worse than looking at the monitor, and if one isn't looking for this potential flaw, would most even see it? My mantra is "Perfection is the enemy of good enough."

"What a beautiful print! But, I notice that if I put my loupe on it,........."

Of course, one could spend a boodle on a high pixel count monitor if this turns out to be an issue.
 
A few issues to keep in mind:
- Keep an eye on light bleed and things like indicator lights on a monitor. - Dragging your print over the power button while it is on probably won't do you much good.
- "Black" on a monitor isn't always actually without light, so be wary of fogging, or inconsistent exposure from inconsistent time on placement.
- Colours aren't reliably monochromatic, and how much of different colours gets blocked will depend on the panel. Your papers may react slightly differently than you expect.
- "Contact" with the pixels is going to depend on panel design and construction. Some designs end up with a fairly deep gap between the actual pixels and the front surface of the panel. - No idea how easy it will be to ind a panel with a happy medium of enough bleed to not show gaps between the pixel elements, but also not so much as to leave you with a fuzzy image.
- Controls seem to be one of the most awkward parts of this - All my monitors display what input they're reading from when I turn them on, so exposure controls might be a bit tricky to sort out a way to make them consistent and reliable.
 
A few issues to keep in mind:
- Keep an eye on light bleed and things like indicator lights on a monitor. - Dragging your print over the power button while it is on probably won't do you much good.
- "Black" on a monitor isn't always actually without light, so be wary of fogging, or inconsistent exposure from inconsistent time on placement.
- Colours aren't reliably monochromatic, and how much of different colours gets blocked will depend on the panel. Your papers may react slightly differently than you expect.
- "Contact" with the pixels is going to depend on panel design and construction. Some designs end up with a fairly deep gap between the actual pixels and the front surface of the panel. - No idea how easy it will be to ind a panel with a happy medium of enough bleed to not show gaps between the pixel elements, but also not so much as to leave you with a fuzzy image.
- Controls seem to be one of the most awkward parts of this - All my monitors display what input they're reading from when I turn them on, so exposure controls might be a bit tricky to sort out a way to make them consistent and reliable.

I appreciate your input! Except for the new knowledge about LED panel construction, I see everything else as correctable within controls. For instance, what I see on the monitor doesn't have to be what gets developed. Highlights blocky? Cut the exposure next time.

Not pure black? Doesn't matter since the emulsion is not color sensitive unless one is using VC paper and the imparted color is part of the grading spectrum. Even then correctable.

I have that 48 step tablet on file, and I found it extremely useful in a simple density calibration. Before putting it up, I had great highlights, blocked shadows. Played with the brightness control, went the other way. Backed off, and it's the Goldilocks porridge temperature........just right.
 
Hey! You have the makings of a fun toy camera; a small LCD screen, a cheap sensor, 4x6 paper in a cartridge and a high-energy positive developer all smashed-up... A Paperoid instant camera...
 
I suppose it's possible. But I think with the pixel so far away, it would be hard to get a sharp image. Also the computer screen isn't a very sharp image anyway, so you likely would a pretty low resolution image in the end. Also, you'd have to figure out a way to control the time of the light. All of my monitors come up with a menu or some text display when you first turn them on, and you don't want that showing up on your print (probably). So you'd likely need to control that via software.

Still, it might produce some weird and interesting results. It could be a fun project, but I wouldn't expect high quality results from it, no matter how much your tweaked it. But don't let that stop you from trying!
 
So.... you're planning on layer a piece of photo paper face down on a monitor, exposing it to whatever inverted image you have on the screen? Wouldn't it be unsharp?
 
It works. I remember I've seen it done some time ago by an Italian photographer with a Retina display, but I don't have the link anymore.
 
The resolution of my monitor maxes out at 1920 x 1080 pixels. The screen is about 12"x 21" in size.
A piece of photographic paper is capable of a lot more resolution than 1920 x 1080 individual pieces of detail.
However, if you are looking for low resolution, not very sharp results, it could be really fun.
 
From somebody has done it - dang! - to it's going to be a blurry mess. Can't see how angle of view has anything to do with something laying on the surface.

I don't see anything that can't be surmounted. If my monitor goes to sleep and I touch a key, it pops right up w/o other stuff going on. Start the timer then.

I acknowledge the probable limitations of sharpness w/o going to a crazy expensive monitor. But that in itself could be interesting, think what the whole lomographic philosophy is built on. Now it's a friggin' empire! My old plain Jane monitor is 100dpi, far below "photo quality" in the printing trades, for sure. But who knows what the outcome will be w/o trying.

And my real interest is using Rockland type emulsion on various transparent substrates where being super sharp wouldn't matter.

Kodak had a paper called Translite for backlit advertising purposes. It's in my sample book. A thin paper with emulsion on both sides. Years ago I thought, 'What if you did that with thick media? Like 1/4", 1/2", more? Would there be a depth when not viewed straight on?" I suspect so. A friend of mine had a B&W image on glass from the 1920's? hung on a large window, and it was stunning. Stopped you in your tracks.

Printing on paper is, I hope, just a stop on the way to that. Perhaps it will be a new lomographic!
 
There are at least a couple of threads here where this idea has been explored, if I recall correctly. One was using a ipad like tablet for making a contact print and another using a iPhone as a negative in an enlarger. Might want to search those for background.
 
My generic old Dell monitor is 100dpi. If I've done my math right, that .002 inch per dot. Twice the width of a human hair. Presuming that hair was at a 1:1. real life to on the screen.

Has to be in the ball park of OK. I think.
 
There are at least a couple of threads here where this idea has been explored, if I recall correctly. One was using a ipad like tablet for making a contact print and another using a iPhone as a negative in an enlarger. Might want to search those for background.
I went back a few years in the hybrid workflow/digital negative threads and didn't see anything on those lines. A tablet is, of course, just a smaller version of my monitor for this purpose. Not sure how the second option could work meaning both transparency of the screen and the matter of low resolution once enlarged onto the paper.
 
I went back a few years in the hybrid workflow/digital negative threads and didn't see anything on those lines. A tablet is, of course, just a smaller version of my monitor for this purpose. Not sure how the second option could work meaning both transparency of the screen and the matter of low resolution once enlarged onto the paper.

searched for "ipad negative" on the whole site:

https://www.photrio.com/forum/threads/ipad-enlarger.157201/

https://www.photrio.com/forum/threads/iphone-negative-in-the-enlarger-it-works.163296/
 
Last edited:
Alternative printers like me could never do this because of the need of the UV light but for the regular silver gelatin, one could as well use a digital projector to do the "negative-less" printing that might be a better way than the contact on the monitor. No?

Not sure what kind of pixel density one is getting these days on a good projector though. May be not as good as a high-end monitor.
 
The resolution of my monitor maxes out at 1920 x 1080 pixels. The screen is about 12"x 21" in size.
A piece of photographic paper is capable of a lot more resolution than 1920 x 1080 individual pieces of detail.
However, if you are looking for low resolution, not very sharp results, it could be really fun.

Yes, I think I have a similar monitor, which is 24". It has a resolution of 1920x1080 pixels at a size of 29x51 cm (20x11,4"). That would give me a print resolution for a contact print of 1080 / 11.4 = 95 dpi (same horizontally 1920 / 20 = 96 dpi). That's quite low res compared to an average print of 300 dpi.

A Retina display has a much higher resolution. You can calculate in advance what you get from a specific display, from the diameter and the resolution horizontal and vertical (via Pythagoras).
 
Alternative printers like me could never do this because of the need of the UV light but for the regular silver gelatin, one could as well use a digital projector to do the "negative-less" printing that might be a better way than the contact on the monitor. No?

Not sure what kind of pixel density one is getting these days on a good projector though. May be not as good as a high-end monitor.

The "Cinevator" did this for motion pictures as early as 2008. I had restored sections of a color 35mm motion picture film printed at Technicolor LA in 2009 on one of these and it did a decent job. At the time, it was only HD, but now they make a 4K version.
https://en.wikipedia.org/wiki/Cinevator
 
The "Cinevator" did this for motion pictures as early as 2008. I had restored sections of a color 35mm motion picture film printed at Technicolor LA in 2009 on one of these and it did a decent job. At the time, it was only HD, but now they make a 4K version.
https://en.wikipedia.org/wiki/Cinevator

With 4K projected on a 10" long side, it would be 400 ppi which would be a pretty good number for printing a typical 8"x10" print. Compare that to an Apple iPad Pro with Retina display (2048 x 2732 pixels) that comes in at 265 ppi for a 10.3"x7.7" (by by calculation.)
 
With 4K projected on a 10" long side, it would be 400 ppi which would be a pretty good number for printing a typical 8"x10" print. Compare that to an Apple iPad Pro with Retina display (2048 x 2732 pixels) that comes in at 265 ppi for a 10.3"x7.7" (by by calculation.)

Our math's are widely divergent. I just looked at I presume typical 4K monitors on eBay. A 27" diagonal wide screen should be 13.5" on short side. I ratio'ed that from my 21" WS. At, I presume typical 2160 pixels stated, that would be 160 pixels/inch.

There are things to consider that are way past my pay grade despite trying to get a handle on them for years. Old timer lith printers talk about lines per inch, ink jets talk about dpi, and monitors have a separate pixel for each of the three colors. So where does that leave this? I have no idea.

Then we have the fact that most films don't go past 125lpi contact printed, although a few like TMY can do 200lpi in best of lab circumstances. And then there are the lens.............

It looks like it will have to be an outright empirical experiment to determine how satisfactory my idea is.
 
Possibly adding a privacy screen would reduce some scatter and sharpen the image.

My limited experience photographic computer screens is that the images come out looking quite soft.
 
You're not too off the mark. I remember when I was an undergrad back in the late 80's, I worked for a photography and a graphics unit at my university that had one of the first graphics computer called the Targa. They had a film recorder device that had a high resolution black and white monitor with 3 color filters which was red, green and blue. The recorder would make 3 different exposures with each filter.
 
Our math's are widely divergent. I just looked at I presume typical 4K monitors on eBay. A 27" diagonal wide screen should be 13.5" on short side. I ratio'ed that from my 21" WS. At, I presume typical 2160 pixels stated, that would be 160 pixels/inch.

There are things to consider that are way past my pay grade despite trying to get a handle on them for years. Old timer lith printers talk about lines per inch, ink jets talk about dpi, and monitors have a separate pixel for each of the three colors. So where does that leave this? I have no idea.

Then we have the fact that most films don't go past 125lpi contact printed, although a few like TMY can do 200lpi in best of lab circumstances. And then there are the lens.............

It looks like it will have to be an outright empirical experiment to determine how satisfactory my idea is.

Hi, Paul:

You are correct in your math. I was calculating a different scenario though, namely projecting an image with 10" on the long side using a 4K projector (meaning there are 4000 pixels on the long side.) In that case, the ppi comes to 4000/10 = 400.

In digital realm the old lpi measurement can be looked at in this way: In order to resolve 125 lpi, one needs 125x2 = 250 pixels per inch at the minimum. Conversely if the source is 160 ppi, the best one can resolve is 80 lpi.

And it requires 530 ppi to match the resolution of the human eye: http://www.clarkvision.com/articles/eye-resolution.html

Agree that nothing beats empirical data to figure out how good an idea is. The proof of the pudding....:smile:


:Niranjan.
 
Last edited:
Photrio.com contains affiliate links to products. We may receive a commission for purchases made through these links.
To read our full affiliate disclosure statement please click Here.

PHOTRIO PARTNERS EQUALLY FUNDING OUR COMMUNITY:



Ilford ADOX Freestyle Photographic Stearman Press Weldon Color Lab Blue Moon Camera & Machine
Top Bottom