Don,

I know you meant the other Michael :-)... But you can open the Max file, which is a text, in the QTRgui and it will convert it to a .qidf profile when you save it. Also, the curve creator in the gui is a tab, and you can cut and paste the .txt file line created on the mac version directly into the space in that tab. You can open the created .qidf file directly in MS word, modify it, and reload it in QTRgui. Or you can send the file to a Mac user and they can open it as a txt file and use it in QTR.

There are some options available in the gui it seems that are not apparent when you open the file as a txt file in PC or Mac. For example, there are tone curves one and two, which can be ignored. The graphing features of the gui make it very useful for gauging how changes would affect your negative.


Mike

But you can open the Max file, which is a text, in the QTRgui and it will convert it to a .qidf profile when you save it.


For some reason I thought the file M. Schulte mentioned was a binary file.



Also, the curve creator in the gui is a tab, and you can cut and paste the .txt file line created on the mac version directly into the space in that tab. You can open the created .qidf file directly in MS word, modify it, and reload it in QTRgui. Or you can send the file to a Mac user and they can open it as a txt file and use it in QTR.


Yes I'm familiar with the interface having made/modified curves for ink jet printing previously.



There are some options available in the gui it seems that are not apparent when you open the file as a txt file in PC or Mac. For example, there are tone curves one and two, which can be ignored. The graphing features of the gui make it very useful for gauging how changes would affect your negative.
Mike

I'm still curious to find out meaning of the reference to the inkseperation.psd file mentioned in the QTR Tutorial and by Kees. Is this something missing in the PC distribution?

I printed the ink seperation file last night on three substrates with PK and MK inks. I assume that choosing the correct ink limit setting for making digital negatives will be different than choosing an ink limit for inkjet prints. The ink limit choosen for printing digital negatives would be the setting that produces paper white when printing the the 21 step tablet at the minimum printing time. Picking that setting seems to be a process of trial and error. Choose an ink limit number and see if it works.

BTW, the African Chruch on Sapelo, Is. that you have an interior shot of on your web site not longer exists like it was. The chruch has been entirely restored.

Don Bryant

Don,

That is amazing that they restored the church. It was amazing when I photographed it - I photographed it on December 29th 1999. My girlfriend (now wife) and I stayed at LuLu's trailer and rented a car from them. It was a remarkable couple of days. Do you know when they restored it? The back end was falling off, and the porch had caved in.

Mike

Don,

That is amazing that they restored the church. It was amazing when I photographed it - I photographed it on December 29th 1999. My girlfriend (now wife) and I stayed at LuLu's trailer and rented a car from them. It was a remarkable couple of days. Do you know when they restored it? The back end was falling off, and the porch had caved in.

Mike

I can't remember when it was restored but the last time I visited it had been completely restored with the help of The Savanah Historical Society. I've stayed at Lulu's also, renting a car too and I've also stayed at the Reynolds mansion several times. Much better digs, food, and transportation, but more expensive. It would make a great place to host a field workshop for photography.

Hog Hammock is changing too. The land is being slowly sold to developers and new homes are being built. The old society there is dying out and the heirs want to cash in on the land value.

Don Bryant

Don,

I am sorry to hear that. I knew that developers had been trying to buy up the land, and that there was great resistance, but I guess it is hard to resist the money. I am trying to remember the name of the photographer from Texas who had photographed (with 4x5) there - both the people and the land. He printed on Forte warm tone, and the prints were gorgeous.

Maybe we should try to have a free workshop there before there is too much more change. In any case I will have to try to go there this Feb. and photograph.

Mike

Don,

I am trying to remember the name of the photographer from Texas who had photographed (with 4x5) there - both the people and the land. He printed on Forte warm tone, and the prints were gorgeous.


Sorry I don't know the photographers name. I may have seen the work but can't bring it to mind now.



Maybe we should try to have a free workshop there before there is too much more change. In any case I will have to try to go there this Feb. and photograph.
Mike

February and March have always been very cold for me on the Georgia coast. Maybe late March or early April. Actually any time it is warm or hot is fine with me.

Like I said the Reynold's mansion would be a really cool place to have a workshop but expensive. The state also requires at least 20 people now to lease the mansion for a week. The staff is great, the food is really good, access to the interior of the mansion and grounds is unrestricted and there are two large vans at the groups disposal with all the gas they can use. Rental bikes are also available. Reservations usually have to be made 1 year in advance. It's been about 4 years since I've been down so I wouldn't mind going back.

Don

Hi,

We talked about using QTR for digital negatives and I noticed that there are four (or maybe more) different approaches. I am trying to list them here:

Ah, a subject dear to my heart... I'll expand on this a bit.


1. QTR BW workflow with quad black inks

This is what QTR was made for. You have to use a dedicated printer with black and grey inks or one of the newer K3 printers. Third party inksets are sold by MIS or Cone and others.

Each grey ink overlaps the previous and this can be controlled in the inkdescriptor file. A no K, only grey, approach is also possible. Process related density range can be controlled by setting ink limits. Process related correction/linearization curves can be specified in the gray_curve setting or applied in photoshop. (Note: does QTR handle these curves in 16 bit? If not, it is probably better to keep using them in photoshop on 16bit files)

Yes, QTR handles the curves in a better than 8 bit fashion, although if memory serves, it's 14 bit, to allow some overhead.

Part of the "power" of the quad black approach is that it largely addresses most of the banding and dither issues some folks have been experiencing. Another part is that it allows you to run high ink levels on all the blacks and grays, and that "fills in" the gaps between dots. "negative" dots (gaps between black or dark gray dots) print as black speckles in what should be the lighter tones, and are incredibly annoying.

Another important advantage is that the carbon black inks have virtually the same density to UV as they do to visible light, just like a regular silver negative. So densitometers and sensiometric curves work. Because the density is the same to blue and green light, multi-grade papers work with their normal filtration.

And the last important advantage is that you can "read" these negatives. I've worked with all those weird "multchromic" negatives, and they just are so much work to visualize.

My own workflow uses five dilutions of black for digital negatives on one of my Epson 2200 machines. It's loaded with an inkset I call "Wiz7" (I have a tendency to name things after myself).

100% MIS "Eboni" for matte black
100% MIS PKN ("neutral" photo black, cooler than Epson's photo black)
32% PKN
10% PKN
3.2% PKN
1% PKN
MIS "glop" (a clear varnish that can be used to fill in the uninked areas of a B&W print, or applied to the whole print as an "overcoat").

For digital negatives, I print with the 5 dilutions of PKN.

For glossy prints, 5 PKN and glop

For matte prints, Eboni and 5 PKN. (Eboni for density from about 1.7 to 1.3, 100% PKN for 1.3 to 1.0, etc...)

I'm considering loading an 1800 with 8 dilutions of PKN, 100, 56, 32, 23, 10, 5.6, 3.2, and 2.3% as a dedicated negative machine. Between the smaller 1800 dot size and the extra blacks between my normal 5 "root 10" blacks, the negatives should be the best thing out there.



2. QTR BW workflow with K and LK in a printer with color inks.

As I understand Ron correctly, and after looking at his 2200 Pd and silver sample files, in his workflow only K and LK are used in combination with ink limit settings for density range control. All other inks are not used by specifying them as 'unused' or setting inklimits to zero. As an only grey approach it is not very different from the first approach but it uses only two inks.

A quite satisfactory approach, although it will result in more white speckles in light tones on the print.


3. QTR BW workflow with all (color) inks.

This workflow uses all inks with or without K an LK to print a BW negative with all inks. Default ink limit settings control negative densitity range.
Ron's earlier example files are using copy_curve to copy and set values for each color. But individual values for each ink after measuring the inkseparation print can be set in the descriptor file also.

This will work a lot better if you print a QTR calibration pattern, print that pattern onto platinum, and use it to determine the ink order based ont eh UV blocking ability of each of the colors of Epson ink. The resultant negative will look very strange, but it will work very well. As I recall, full strength magenta falls in between K and LK and "fixes" the speckles in light tones quite well.



4. QTR colorized negatives

This is a different approach and maybe combines the best of two worlds. Here the process related density range is achieved by spectral density and finetuned by ink limit settings. For each CMY color and/or two color combinations CM, CY, MY a monochrome QTR profile is made. All other inks are set to unused. CY gives a high contrast range suitable for long scale processes like salt or albumen printing. CM gives a low contrast suitable for gum printing. Contrast control and finetuning can be done by mixing two QTR-curves or by taking down inklimits (or both).

OK, this one I've honestly not seen before.

Since QTR dithers in more than 8 bits, I'd expect QTR results using just K and LK with curves built for long or short scales to exceed its performance by a wide margin.


This method would work even better with a ternary CMY calibration file of some sort to choose the right color for each process.

What approach gives the best results is difficult to say. When density range has to be very long, a spectral density negative might be the way to go.

To get the smoothest negative possible probably asks for a print with as many inks as possible. Inks that behave differently (K) than others (colors, greys) can be problematic so an 'all colors, no K' BW approach might be interesting. When using K2 K3 inksets a toner color can be mixed in for density range control.

And there's allways the printing substrate that has a big influence on the density range and smoothness of the negative. Different printers and inksets of course too.

That's an understatement.

Have fun.

Whiz,



Another important advantage is that the carbon black inks have virtually the same density to UV as they do to visible light, just like a regular silver negative. So densitometers and sensiometric curves work. Because the density is the same to blue and green light, multi-grade papers work with their normal filtration.


So why is this important? Are you suggesting that you will change the filtration once a specific curve is calibrated for a specific contrast setting?



And the last important advantage is that you can "read" these negatives. I've worked with all those weird "multchromic" negatives, and they just are so much work to visualize.


Why do they need to be "read" at all? The negative is going to be contact printed for a specific time with no dodging and burning.



My own workflow uses five dilutions of black for digital negatives on one of my Epson 2200 machines. It's loaded with an inkset I call "Wiz7" (I have a tendency to name things after myself).

100% MIS "Eboni" for matte black
100% MIS PKN ("neutral" photo black, cooler than Epson's photo black)
32% PKN
10% PKN
3.2% PKN
1% PKN
MIS "glop" (a clear varnish that can be used to fill in the uninked areas of a B&W print, or applied to the whole print as an "overcoat").

For digital negatives, I print with the 5 dilutions of PKN.

For glossy prints, 5 PKN and glop


It sounds to me that you are make printing digital negatives and ink jet prints way too complicated.



This will work a lot better if you print a QTR calibration pattern, print that pattern onto platinum, and use it to determine the ink order based ont eh UV blocking ability of each of the colors of Epson ink. The resultant negative will look very strange, but it will work very well. As I recall, full strength magenta falls in between K and LK and "fixes" the speckles in light tones quite well.


I've thought of printing the ink seperation test to determine the UV blocking when printed by QTR. Can you explain what you mean by ink order?

Don Bryant

Whiz,
Don,

I'll assume you meant no insult, but a "wiz" is someone who's good at something. Short for a "wizard". Around here, to "whiz" is to urinate.


So why is this important? Are you suggesting that you will change the filtration once a specific curve is calibrated for a specific contrast setting?

Exactly. Because densitometers don't tell the whole story. You may get your curves perfect, whether it's with densitometers, software like PDN, or lots of work, like Burkholder, and get a print with a great match to the screen, or a great match to your vision. Then you put it in a different light, or put it behind glass (you have any idea how much DMAX glass steals?) and you decide you need to boodt or decrease the contrast.

Or because paper changes from batch to batch, or you want to try a different brand of paper. And developer depletes during a printing session, increasing developing time to compensate changes contrast, and a change of filtration can bring you back on spec.

There's also the issue that, because the two layers of multigrade papers are sensitive to different colors, negatives with grays made up of multiple color inks "speckle" more than negatives with pure carbon black inks.


Why do they need to be "read" at all? The negative is going to be contact printed for a specific time with no dodging and burning.

Again, because you may change dang near any part of the process, and the ability to read a negative can tell you "hey, though I created this negative for multigrade, it looks like it may also work for lith", or "that one I made for AZO is never going to work for platinum, have to make a separate one for that process..."

It sounds to me that you are make printing digital negatives and ink jet prints way too complicated.

Maybe so, but what I'm doing works pretty well for me, my customers like it, and my students like it.

And, if you read Phil's post here about giving up on digital negatives and gelatin prints because of speckled light tones, you'd see that sometimes it does take a bit of work to get the results you want...


I've thought of printing the ink seperation test to determine the UV blocking when printed by QTR. Can you explain what you mean by ink order?

Once you've printed the chart, you can then look at each ink as a different shade of gray. You just look at your darkroom print to determine ink is the darkest (which will be photo black) then the next darkest (probably cyan) and so on, setting QTR up as if it were a seven shade of gray set, following the directions in the QTR manual for building a profile. The trick is to invert the print densities, because QTR isn't designed for negatives, and you have to make the profile generator think you've got positives...

Another important advantage is that the carbon black inks have virtually the same density to UV as they do to visible light, just like a regular silver negative. So densitometers and sensiometric curves work. Because the density is the same to blue and green light, multi-grade papers work with their normal filtration.

So why is this important? Are you suggesting that you will change the filtration once a specific curve is calibrated for a specific contrast setting?
One other reason why it's "important"...

Because I have a little spreadsheet that contains a table of the negative density values of my QTR curves (2200 with my inks, 4000 and 7600 with stock Epson inks) and allows me to input the sensiometric (negative density to print density) curves for any paper/developer combination. It then spits out a new QTR curve to go from a gamma 2.2 positive to that particular paper/ink combination. I can read the sensiometric curve right out of a paper manufacturer's data sheets, or print a good old Stoffer 31 step wedge and pop the densities into the spreadsheet (it curve fits any number of densities)

So, develop one QTR curve per printer/ink/substrate for a good, smooth negative scale, one sensiometric curve per paper/chemistry combination, and can generate a negative on any machine for any paper. Get a new printer? Run one QTR profiling procedure to set new ink limits, linearize, and feed the densities into the spreadsheet and "poof", I've got fully functional curves for 15 darkroom processes. Decide to try argyotype? Print one Stoffen wedge, measure it, and I've got fully functional curves for all three printers.

Joe,


I'll assume you meant no insult, but a "wiz" is someone who's good at something. Short for a "wizard". Around here, to "whiz" is to urinate.


An unconcious typo.




There's also the issue that, because the two layers of multigrade papers are sensitive to different colors, negatives with grays made up of multiple color inks "speckle" more than negatives with pure carbon black inks.


I prefer to use graded papers to eliminate the problem of colorized negatives.



Again, because you may change dang near any part of the process, and the ability to read a negative can tell you "hey, though I created this negative for multigrade, it looks like it may also work for lith", or "that one I made for AZO is never going to work for platinum, have to make a separate one for that process..."


That is one of the short comings of digital negs.

Since you mentioned students, seems like I recall that you mentioned on Photo.net that you have a book about printing digital negatives. If so is it available?

Thanks,

Don Bryant