Both of these curves worked in the past. I developed these curves and have been printing both salted paper and carbon curves on my 7900 with no problems. The carbon curve does look a little bumpy but the salt curve does not and as I said the carbon curve works fine for me and worked at MMW until recently. I also don’t understand why other curves would print without banding, suddenly just these two.
Just downloaded this curve and looked at it in QTR Curve. This is definitely not based on the carbon curve I created nor is it a MMW PiezoDN curve. MMW uses a 4900 which has ten channels with some of the channels remapped including K. All of the MMW PiezoDN curves (and all PiezoDN Curves in general) use seven channels including GO.
My mistake. This looks like the carbon curve minus the GO.
This was a modified (limited) curve made a long time ago
-w
I just printed from my MAC on to Pictorico the curve you smoothed. The printed neg looks essentially the same. (the same lines in the black areas.). Nozzle checks before and after still look good, as in the prior photo I took, . In early afternoon I’ll try printing from a PC, . (and different Quad RIP) and see if that makes any difference.
So we have, so far,
-3 different computers (2 Mac, 1 PC)
-3 different QuadRIP
-2 iterations of the same curve. (original and smoothed)
-2 different printers (3800 and 4900)
-2 different sources (at least) of Pictorico. (I print from both a roll and cut)
-2 different .quad (salt, carbon) causing problems. (Also I can get the same problem with cyanotype, though not to the same extent due to what I normally print.)
- I hear that the lines were there in the summer, too,—so 2 different humidity situations.
Wow.
And all nozzle checks are good?
it may be a bunk head
-Walker
Can you upload the 4900 curve you are using?
I can specifically again in a few hours. However the unsmoothed one is already here as is the one Keith smoothed.
yes but i would like to see the original 4900 curve, not the one you remapped.
thanks
or call me at 266-3295. I have an idea what the problem might be, but I need to know which channels are being used. There has been a lot of remapping and its possible it is an older curve.
Nozzle check before and after printing looks good. No blank spots. No offset lines. I posted a photo of the nozzle took a few posts back.
I suppose both the printers we have been testing on are on their last legs. That might explain why the curve works so well on Alan’s printer, but not the other 2.
What are your thoughts on the P 800 for digital negatives? How about the p600?
Just printed a 10 ink flush image using calibration mode and there was banding across all channels. Could this be a head alignment issue? or could there be something on the printhead that is hitting the film? Doesn’t explain why some curves print without banding.
That probably rules out the quad as the cause of the problem, even though the wavy channel curves of the unsmoothed one can’t be good.
One question that comes to mind as I was about to try it on one of my 3880s is the about the remapping. Since you say you used it with the same bad results on both a 3800 and a 4900 does that mean that both have the same remapping? Mine is setup P2, but I’ll try it anyhow … Much of it is insanely dense due to MK where you have PK, but I don’t see any banding or lines.
You also just indicated that this isn’t the only quad that is giving you this problem — salt and cyanotype quads as well as carbon. I missed that earlier if you had mentioned it. I think this supports my suspicion that it is not restricted to only the darkest tones, but is just gets harder to see as negative density decreases.
We’ve gone through everything I can think of with nothing conclusive. I’m starting to think that, as unlikely as it may seem, you might have 2 printers with failing heads.
Is there another printer you can try this on?
Keith
Regarding the remapping. I believe remapping was done on the 4900 some time between summer and fall, but I can’t say for sure. The remapping I did for the 3800 this summer was removing the gloss, and switching around a couple of channels. I triple checked sublime text so I don’t think I made a mistake.
In a couple of days a different 4900 will be available to try.
Love to get feedback about using a p800 vs a p600 for digital negs. I just got a p800 and decoder board but haven’t switched from Epson Inks yet so I have the option to turn it into a Piezography Printer instead of keeping it for Cone Color as planned. (I was about to run out of Epson ink when the printer developed a problem so they sent me a “new” one, and more color ink.) I can live with 13 inch negatives done on a p600 but don’t want to go that route if in the long run the p800 makes better negs. Also there are the small carts!
Regarding the 4900 original curve: Looks like I don’t have it any more. I got it this summer in July during the Carbon Class, if that helps.