Digital BW, The Print

--- In DigitalBlackandWhiteThePrint@yahoogroups.com, "Doug Nielsen" <dougnielsen@c...> wrote:
> 
> Hi
> 
> I probably can't offer you much help. But, I've been messing with making digital 
> negatives with a 2200 for silver printing for a couple of years now. And I have encountered 
> enough pitfalls that I've already quit several times. So, I have some comments.
> 
> With regard to the density crossover you are seeing. First make sure that the reversal isn't 
> related to the positioning of the steps on the printed negative.

It's not. It shows up when I do a 101 step chart (10x10 with one extra square) in linear order, or a 300 step chart, with 100 values repeating, each repeated on the page three times, in random order, so it can be read by the EyeOne.

>I have found that I get 
> significant variation in ink density with location on the page. It's possible that the 
> arrangement of the steps on your 101 step-wedge is such that a an area on the page of 
> improper ink densities makes it look like a crossover. For example, I am currently using a 
> 129-stepwedge that goes from the highest ink density step in the upper right corner of 
> the 8x10 page. The steps reduce in density in twelve steps from right to left with 12 steps 
> per row and proceeds in 11 rows to lowest density near the bottom center of the page. My 
> printer apparently produces a vertical band of improperly reduced densities (a dip in 
> density of about 0.04 at the band center). The band is about 2-3 inches wide and affects 
> the medium to low densities the most. The result is I get a plot of densities with a very 
> patterned oscillation. And a different arrange of the steps in the wedge could lead to some 
> very wrong conclusions.

That's the beauty of the EyeOne and a nultiple pattern where each step appears multiple times. If the 23% step on the upper right corner doesn't match the 23% stel near the left side of the middle of the page, you get an instant flag that something is wrong. That's how I learned to even out my contact print light source, and turn the frame several times while printing.
 
> The above observations were made when I was workiing with color or spectral density 
> negatives on 
> Pictorico Glossy Film paper. The color I was using was R=255, B=G=0. 

That's sort of what I'm trying right now. Except I'm using a reddish black. I do the mix in PhotoShop by going to "levels" and raising the lower red limot from 0 to 128 (for 50% red), or 96 (for 37% red). You can mix red and black pretty freely for Ilford (oe Kodak, for that matter) multigrade. Red has both magenta (blocks green) and yellow (blocks blue). 

> About a year ago 
> I also tried Glossy Film with Black ink negatives. I quit after finding an even more 
> pronouced ink density variation (about .08 density). I didn't pursue the problem but as I 
> remember the density seemed to vary from corner to corner in both x and y. I have since 
> read that the Epson black ink is a real trouble maker, so I decided to try the spectral 
> density approach (again) to avoid the use of the black ink.
> 
> After all that, I do have a recommendation.

I should have one soon. I've tried a few more things, and have gotten some success...
 
>  --- If you are going to do silver prints only, try the glossy film paper with spectral density 
> negatives. I have found the glossy film apparently takes the ink more smoothly than OHP 
> and the spectral density negative (at least with the colors I am using) yields a much more 
> well behaved adjustment curve. I think that "Adjustment Curve" is Dan Burkholder's 
> terminology. Mark Nelson uses "Process adjustment Curve".

I just use the term "curve". I'm a bit weird, I make a curve that does the linearization and converts the image to a negative. I don't want to see the "corrected" positive image, and two conversions are risky in PhotoShop, they make the final result gamma dependent.

> I have tried QTR as well as the Bowhaus OPM rips and came to the same conclusion that 
> you did.
> 
> I would certainly appreciate hearing from you about the success or failure of your use of 
> the 4000. I have been considering replacing my 2200 to solve the ink density variation 
> problem, but have been reluctant not knowing if the 4000 might have the same problem.

I don't see any ink density variation on the 4000, or my 2200. Do you always print in unidirectional mode, and align the printer for the OHP or white film you're using?

I'm one big step closer to a solution on the 4000. I printed paper negatives (Kirkland glossy) for four paper settings on the 4000. And I learned that the inl kaydown is dramatically different on the ones I tested:

Premium Glossy Photo Paper
Premium Glossy Photo Paper 250
Premium Luster
Premium Luster 250

My first curves were done on the Premium Glossy (not 250) setting. I've discovered that even the "250" and "not 250" versions of Premium Glossy Photo Paper vary dramatically from each other. 

Luster 250 seems to be the most predictable. No actual crossover, but a big flat spot on the curve that is really annoying, when printing a black negative (like the 2200, a black negative on the 4000 has greenisn mid tones). Wien using the 37.5% red mix, the negatives are ugly brown, but fit the tonal range of Ilford Multigrade pretty well.

The problem with the 4000 is that it has about 40 basic paper types, while the 2200 had 6. So checking them all out is going to take some time.

Ciao!

Joe