QTR-Quadtone RIP

I'm trying to use version 2.6 and a 3800 to make digital negatives. I
can't seem to get even highlight densities (skies mainly)to print
without odd very random stripes of heavy magenta. I'm using an even
dark ink mix of 15 (black, cyan and magenta) and 8 yellow and 32 K
boost, but every so often I'll get these 1/2-1" bands with way too
much magenta in the mix. Sometimes these stripes will alternate the
length of the sky area, other times there will be a single very wide
stripe at the end of the same sky area. The ink level on the printer
confirms this- the magenta cart is half as full as the other dark
inks- which suggests it's happening more than I'm aware of.. I've
tried changing the dark ink limits slightly to no effect. Any ideas
much appreciated.

What dpi are you using? What material are you using? 
Try a few different dpi settings and see if that makes  difference. Also go into the driver setting and locate the density setting..try a few variants.. It sounds like your inks are not "adhering" to the surface possibly.. When I print on Mylar for a transfer patch fix that's  what I see. 
I'm not intimate with the 3800 but it has a pretty good dither pattern... I'm leaning towards a material issue.. 
Have you done this successfully before with this material?  or is it new turf...........

jimbo

  ----- Original Message ----- 
  From: colinflanary 
  To: QuadtoneRIP@yahoogroups.com 
  Sent: Sunday, October 12, 2008 10:21 AM
  Subject: [QuadtoneRIP] Inconsistant magenta density with digital negatives



  I'm trying to use version 2.6 and a 3800 to make digital negatives. I
  can't seem to get even highlight densities (skies mainly)to print
  without odd very random stripes of heavy magenta. I'm using an even
  dark ink mix of 15 (black, cyan and magenta) and 8 yellow and 32 K
  boost, but every so often I'll get these 1/2-1" bands with way too
  much magenta in the mix. Sometimes these stripes will alternate the
  length of the sky area, other times there will be a single very wide
  stripe at the end of the same sky area. The ink level on the printer
  confirms this- the magenta cart is half as full as the other dark
  inks- which suggests it's happening more than I'm aware of.. I've
  tried changing the dark ink limits slightly to no effect. Any ideas
  much appreciated.



   

[Non-text portions of this message have been removed]

Hi Jimbo,

Many thanks for the suggestion and quick reply.

I'm using 360ppi file sizes and 2880 dpi in the QTR gui. The substrate
is pictorico OHP. I've tried both the adaptive hybrid and ordered
dither algorithms and bi- and uni-directional printing.

The QTR routine and the 3800 are somewhat new to me, but I've
previously used a B9180 and pictorico with great results, so I don't
think it is a substrate issue. Also, the inconstancy of the problem is
odd- I have gotten great results with the same profile and settings on
the 3800 as recently as last weekend- which makes me think it might
possibly be a printer issue. But I've run cleanings and maintenance
cycles to no effect. It's just hard to imagine what could make the
magenta ramp up so bizarrely. I only use the printer for digital
negatives, and the amount of magenta ink I'm going through is very
strange considering all the dark ink limits are set to follow the K curve.

 BTW, here's a copy of the profile I'm using.

PRINTER=Quad3800
CURVE_NAME=CarbonPk_LanaHP
GRAPH_CURVE=YES
N_OF_INKS=8
DEFAULT_INK_LIMIT=100
BOOST_K=32
LIMIT_K=15
LIMIT_C=15
LIMIT_M=15
LIMIT_Y=8
LIMIT_LC=35
LIMIT_LM=35
LIMIT_LK=35
LIMIT_LLK=0
N_OF_GRAY_PARTS=2
GRAY_INK_1=K
GRAY_VAL_1=100
GRAY_INK_2=LK
GRAY_VAL_2=33
GRAY_HIGHLIGHT=0
GRAY_SHADOW=0
GRAY_OVERLAP=
GRAY_GAMMA=0.9
GRAY_CURVE="0;0 10;10 25;20 35;30 50;50 56;59 62;70 69;76 76;81 85;86
95;94 100;100"
N_OF_TONER_PARTS=0
TONER_HIGHLIGHT=10
TONER_SHADOW=10
TONER_GAMMA=1
TONER_CURVE=
N_OF_TONER_2_PARTS=0
TONER_2_HIGHLIGHT=10
TONER_2_SHADOW=10
TONER_2_GAMMA=1
TONER_2_CURVE=
N_OF_UNUSED=1
UNUSED_INK_1=LLK
COPY_CURVE_C=K
COPY_CURVE_M=K
COPY_CURVE_Y=K
COPY_CURVE_LC=LK
COPY_CURVE_LM=LK


--- In QuadtoneRIP@yahoogroups.com, "mrjimbo" <mrjimbo@...> wrote:
>
> What dpi are you using? What material are you using? 
> Try a few different dpi settings and see if that makes  difference.
Also go into the driver setting and locate the density setting..try a
few variants.. It sounds like your inks are not "adhering" to the
surface possibly.. When I print on Mylar for a transfer patch fix
that's  what I see. 
> I'm not intimate with the 3800 but it has a pretty good dither
pattern... I'm leaning towards a material issue.. 
> Have you done this successfully before with this material?  or is it
new turf...........
> 
> jimbo
>   ----- Original Message ----- 
>   From: colinflanary 
>   To: QuadtoneRIP@yahoogroups.com 
>   Sent: Sunday, October 12, 2008 10:21 AM
>   Subject: [QuadtoneRIP] Inconsistant magenta density with digital
negatives

> 
> 
> 
>   I'm trying to use version 2.6 and a 3800 to make digital negatives. I
>   can't seem to get even highlight densities (skies mainly)to print
>   without odd very random stripes of heavy magenta. I'm using an even
>   dark ink mix of 15 (black, cyan and magenta) and 8 yellow and 32 K
>   boost, but every so often I'll get these 1/2-1" bands with way too
>   much magenta in the mix. Sometimes these stripes will alternate the
>   length of the sky area, other times there will be a single very wide
>   stripe at the end of the same sky area. The ink level on the printer
>   confirms this- the magenta cart is half as full as the other dark
>   inks- which suggests it's happening more than I'm aware of.. I've
>   tried changing the dark ink limits slightly to no effect. Any ideas
>   much appreciated.
> 
> 
> 
>    
> 
> [Non-text portions of this message have been removed]
>

--- In QuadtoneRIP@yahoogroups.com, "mrjimbo" <mrjimbo@...> wrote:
>
> What dpi are you using? What material are you using? 
> Try a few different dpi settings and see if that makes  difference.
Also go into the driver setting and locate the density setting..try a
few variants.. It sounds like your inks are not "adhering" to the
surface possibly.. When I print on Mylar for a transfer patch fix
that's  what I see. 
> I'm not intimate with the 3800 but it has a pretty good dither
pattern... I'm leaning towards a material issue.. 
> Have you done this successfully before with this material?  or is it
new turf...........
> 
> jimbo
>   ----- Original Message ----- 
>   From: colinflanary 
>   To: QuadtoneRIP@yahoogroups.com 
>   Sent: Sunday, October 12, 2008 10:21 AM
>   Subject: [QuadtoneRIP] Inconsistant magenta density with digital
negatives
> 
> 
> 
>   I'm trying to use version 2.6 and a 3800 to make digital negatives. I
>   can't seem to get even highlight densities (skies mainly)to print
>   without odd very random stripes of heavy magenta. I'm using an even
>   dark ink mix of 15 (black, cyan and magenta) and 8 yellow and 32 K
>   boost, but every so often I'll get these 1/2-1" bands with way too
>   much magenta in the mix. Sometimes these stripes will alternate the
>   length of the sky area, other times there will be a single very wide
>   stripe at the end of the same sky area. The ink level on the printer
>   confirms this- the magenta cart is half as full as the other dark
>   inks- which suggests it's happening more than I'm aware of.. I've
>   tried changing the dark ink limits slightly to no effect. Any ideas
>   much appreciated.
> 
> 
> 
>    
> 
> [Non-text portions of this message have been removed]
>I solved the problem. I had some legacy epson scanner drivers
installed that might have been the problem. I also thoroughly
uninstalled the printer and QTR drivers, then reinstalled everything.
Also, I changed the printer spool settings to load entire file before
printing. So far so good- not sure though which had more impact.