RE: Building PS curves for alternative processes with the Inkjet Companion

Thanks very much Mike, your suggestions are well taken and noted. I'll try
them out soon - this weekend in fact. I do feel like my process is under
pretty tight control but like any photographic process perfection is only a
goal, technique is used to augment artistic intent. My final aim is to be
more productive and have flexibility in printing, not just to become a holy
grail printer. BTW, I enjoyed viewing your online gallery, nice work.

Thanks again,

Don

> -----Original Message-----
> From: Mike Klemmer [mailto:mklemmer@comcast.net]
> Sent: Saturday, May 29, 2004 12:52 PM
> To: alt-photo-process-l@sask.usask.ca
> Subject: Re: Building PS curves for alternative processes with the Inkjet
> Companion
>
> When I build my curves I only look at how the curve output values affect
> the
> density readings of the final print.
>
> For example - building a kallitype curve you may want to begin with a few
> test curves like this:
>
> Curve a:
> Input Output
> 0 0
> 5 1
> 10 2
> 20 4
> 30 7
> 40 10
> 50 14
> 60 20
> 70 30
> 80 40
> 90 70
> 95 85
> 100 100
>
> Curve b:
> Input Output
> 0 0
> 5 2
> 10 3
> 20 5
> 30 8
> 40 11
> 50 16
> 60 23
> 70 34
> 80 50
> 90 75
> 95 91
> 100 100
>
> Curve c:
> Input Output
> 0 0
> 5 3
> 10 6
> 20 8
> 30 9
> 40 12
> 50 15
> 60 18
> 70 26
> 80 38
> 90 80
> 95 95
> 100 100
>
> What's important here is that you have a good sampling across the range of
> all the output values. The output values from 1 - 12 are especially
> critical for nailing down the correct highlight values on your kallitypes.
> Now print out your curves onto step tabs and make a fully toned print and
> then measure the density of each block. Assemble the results by mixing
> and
> matching the input/output values and then assemble about three more
> 'rough'
> final curves and test them to come up with a 'final' curve. For example,
> you may have found from your test curve that the 10%/2% input/output data
> point made a 5% grey density reading on the print. So your final curve
> will
> be 5%/2% input/output.
>
> It's also important to remember that with alt-photo the curve is but one
> variable in the whole operation. Things such as the sensitizer ratio and
> coating thickness, paper variances, your exposure process, etc. all have a
> potent effect on the outcome. Don't get too wrapped up in trying to get a
> 'perfect' curve unless you have a rigid control on all of the other
> variables in the process first.
>
> Hope it helps.
>
> Regards,
>
> Michael Klemmer
>
>
> ----- Original Message -----
> From: "Silver Plated" <dstevenbryant@mindspring.com>
> To: <alt-photo-process-l@sask.usask.ca>
> Sent: Thursday, May 27, 2004 11:26 AM
> Subject: Building PS curves for alternative processes with the Inkjet
> Companion
>
>
> > Good Afternoon Everyone,
> >
> > Recently I purchased an Epson 2200 (an a 1280) and this past weekend I
> had
> an opportunity to make a digital inkjet negative to try printing as a
> toned
> kallitype print. Before I go in to the particulars of my results and
> questions let me point out that to make the negative I used Dan
> Burkholder's
> Inkjet Companion Template, using his curve for palladium prints.
> Additionally my monitor is calibrated and profiled and I'm using Pictorico
> OHP for the inkjet negative substrate. I choose the kallitype process
> since
> it is relatively inexpensive.
> >
> > I knew that using Dan's curve would most likely require adjustments to
> produce a good result, in fact I hoped that the print would need
> adjustment
> to provide myself with the opportunity to learn how to make adjustments to
> curves for various processes. The final print was extremely flat. There
> was
> very little differentiation in most of the steps in the included step
> wedge
> on the print. This is in contrast to the quad tone print I made as a
> proof.
> >
> > The 0% step read about .09 and the 100% step read about 1.35 on my
> densitometer. Most of the mid-tone steps had a reading of about .25 to .35
> (I'm working from memory here). Additionally I have not established the
> minimum print time for black but I assume I'm pretty close since the 100%
> step was 1.35. I plan on establishing the minimum black time this weekend
> with a blank piece of OHP.
> >
> > My question today is; is there a way to correlate my densitometric
> readings that will result in the desired changes in the PS curve to
> produce
> good separation. Also how much difference in log density values should one
> expect to see in the step wedge mid-tones? Also if I read the transmissive
> values on the negative are there aim points for the differences from step
> to
> step that one should observe?
> >
> > Hopefully my questions seem rational and clear, if not, someone, anyone
> please correct me!
> >
> > Also as time permits I plan to test Keith Schriber's colorization values
> and curves along with several other curves different individuals have sent
> me.
> >
> > Thanks,
> >
> > Don Bryant
> >
Received on Sat May 29 12:27:48 2004