color intensity on a smei rotative offset

[filipgbc]

We are working on a semi rotative web offsetpress. Since we changed the 2nd (cyan) with the 3rd tower (magenta)(due some problems), we have problems with full colours.

Orders printed before the change are totally different as printed after the change, and this especially for magenta and cyan.

For example an orange label, with red arrow and a picture in it . Last time we printed this order, all the red was almost orange.

So we needed to pull up the red, but then the orange is coming much to red and the picture is also too red.

We think that small dots are printed to red and the full colours are not red enough. It seems that the contrast in red is much lower as before.

 

[CD102]

Do you have any targets where you can check things like dot gain and ink trap?

 

[filipgbc]

This is very difficult as we print labels in rotation and the gap between the labels is most of the times less than 4 mm. So no plce to put any targets.