iPad enlarger

[RalphLambrecht]

Tried it. Just took a b/w picture (no negative, that will come when it really works) and exposed it for 5sec. That was too much, so I turned down the screen light as much as possible and exposed for 2 sec. That looked a lot better. Looked a bit like a grade 5 print, but ok. One challenge is not to move the paper when exposing and switching off the ipad. The slide show software is a good idea, I think. And less sensitive paper. The best candidate for that is Foma warmtone, which has to be exposed for ages. Unfortunately I don’t have any at the moment.
Keep on trying.
Regards,
Frank

what is the least sensitive paper on the market today?

 

[Frank53]

what is the least sensitive paper on the market today?

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

 

[etn]

Well, I ran a first test today and there were some problems but, they were quite different from what was predicted here;
1.there was no fuzziness at all.the iPad screen is almost in direct contact with the paper and that makes for a crisp print.

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?

 

[etn]

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?

 

[Craig]

some folks really struggle with a lack of imagination and sped more energy into finding ways why things won't work rather than putting that energy into finding solutions.

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

 

[Mr Bill]

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.

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.

 

[David A. Goldfarb]

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.

 

[NedL]

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.

 

[Mainecoonmaniac]

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.

 

[MattKing]

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.

 

[RalphLambrecht]

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?

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

 

[Luckless]

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.

 

[ic-racer]

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.

 

[RalphLambrecht]

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.

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.

 

[klownshed]

...
3. the biggest issue is the brightness of the screen and ts spectral quality I believe the screen is rather blue-rich.

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.

 

[klownshed]

...
3. the biggest issue is the brightness of the screen and ts spectral quality I believe the screen is rather blue-rich.

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.

 

[klownshed]

...
3. the biggest issue is the brightness of the screen and ts spectral quality I believe the screen is rather blue-rich.

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.

 

[Eric Rose]

I'd be interested in seeing your results Ralph.

 

[RalphLambrecht]

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.

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.

 

[John51]

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.

 

[NedL]

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.

 

[sepiareverb]

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.

 

[RalphLambrecht]

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.

this idea is definitely worthy of consideration.

 

[RalphLambrecht]

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.

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

 

[sepiareverb]

Will message you Ralph.