Digital Negatives - Am I Screwed?

[yeknom02]

Question - is it impossible to create digital negatives with a non-Epson printer? All the sites I'm finding on the subject only mention Epson. I have an HP all-in-one printer (Photosmart 5-something-something) and want to figure out how to print some digital negatives on transparency material. But it seems that everyone uses something called QTR, and that it only works with Epson printers.

So, the question is, since I have an HP printer, am I screwed? Should I chuck my new UV light source out the window?

 

[gmikol]

QTR is a very powerful tool to use with printers that it supports, but it isn't the only way.

You can simply print inverted B&W output directly out of Photoshop or whatever imaging program you use, and use some sort of curves function to adjust the tonalities.

You can use Mark Nelson's PDN system of colorized negatives (http://www.precisiondigitalnegatives.com).

Also check out Dead Link Removed which is another colorized negative method.

Hope that helps get you started.

--Greg

 

[DennyS]

You might try something simple first, take a look at this:
Dead Link Removed
This is a summary of Dan Burkholder's approach, and although it's Epson-oriented, it might be pretty easy to translate to another printer. I can generate some pretty good negs using this colorized neg system. Be sure to Google Chartthrob, it might help make things go a lot quicker. Of course, you'll have to do some experimenting...

 

[Ron-san]

All digital negatives require application of a correction curve so that the tones of the negative match the UV response of the emulsion they are intended for. There are basically two places you can apply the needed corrections. One, you can apply them to the digital image file, before it is sent to the printer. This is fundamentally the method used by Burkholder, Nelson, and many others. Two, you can leave the image file alone, but apply the corrections to the printer's ink settings. This is the method that uses QTR. The disadvantage of method one is that the correction curve is usually quite severe and inevitably results in some image degradation. However, it applies to any and all printers, not just to Epson printers. The advantage of method two is that there is no degradation of the image file, and one has complete control over the printer's inks (which allows some subtle manipulations not otherwise possible). But, QTR is only for Epson printers (sob). I really wish someone would step up to the plate and provide a QTR look alike for Canon and HP printers as well.

Bottom line, you can make really good negatives and prints by method one, on essentially any printer (take a look at some of Burkholder's or Nelson's work). You are not screwed by lack of an Epson printer.

Good luck, Ron Reeder

 

[yeknom02]

Bottom line, you can make really good negatives and prints by method one, on essentially any printer (take a look at some of Burkholder's or Nelson's work). You are not screwed by lack of an Epson printer.

Thanks for the comprehensive explanation of the two different approaches. I guess that, in the first method, it would be possible to print out a colorized negative to sort of control each ink's output levels, since (I think) each process has its own characteristic responses to different dyes.

For what it's worth, I'm planning on experimenting with the carbon transfer process.

 

[pschwart]

The aim of colorizing negatives is to find a color that provides sufficient UV blocking to achieve paper white at the base exposure for the chosen print process. Then a correction curve is created to linearize the tones. When you use the native printer driver it figures out how much of each ink to lay down, although Photoshop curves can provide control; if you use QTR you create a profile that controls the output of each ink channel you decide to use. Note that not all printers provide sufficient UV
blocking, even in the Epson family.

 

[MVNelson]

All digital negatives require application of a correction curve so that the tones of the negative match the UV response of the emulsion they are intended for. There are basically two places you can apply the needed corrections. One, you can apply them to the digital image file, before it is sent to the printer. This is fundamentally the method used by Burkholder, Nelson, and many others. Two, you can leave the image file alone, but apply the corrections to the printer's ink settings. This is the method that uses QTR. The disadvantage of method one is that the correction curve is usually quite severe and inevitably results in some image degradation. However, it applies to any and all printers, not just to Epson printers. The advantage of method two is that there is no degradation of the image file, and one has complete control over the printer's inks (which allows some subtle manipulations not otherwise possible). But, QTR is only for Epson printers (sob). I really wish someone would step up to the plate and provide a QTR look alike for Canon and HP printers as well.

Bottom line, you can make really good negatives and prints by method one, on essentially any printer (take a look at some of Burkholder's or Nelson's work). You are not screwed by lack of an Epson printer.

Good luck, Ron Reeder

I think that for Canon printers (iPF...) there is a program (TrueBW) that performs the same principles of QTR but in a very nice graphical interphase .