Author Topic: How black is your film  (Read 4004 times)

Offline Rockers

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How black is your film
« on: March 24, 2016, 09:21:59 PM »
Recently we had to do a power cleans on our Epson 4880. Since that day our films oozing with ink. Honestly it`s not normal, it`s soaking wet. But once we increase the ink reduction the films don`t seem as opaque anylonger.
Now all this makes me wonder how black is the black on the films really supposed to be? I can see a slight shimmer from our  fluorescent ceiling lights when looking through the film. I remember as we used to use the Eposn 4000 and AccuRip we had no issue achieving almost 100% opaque films without having ink oozing of your film.


Offline Screened Gear

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Re: How black is your film
« Reply #1 on: March 25, 2016, 02:55:41 AM »
Darker the better but there is a point when your just wasting ink. Hold your film up to the light and put your finger between the light and the ink film. The film with your finger behind it is 100 percent dark. The rest of the ink film is your percentage. Mine was 98 to 100 percent before I backed off to save ink. I am now at about 5 percent lighter and I have not seen any change in washout or detail I can hold.

Pierre would be a good person to chime in on this since he tests film for guys and knows exactly was is normal.

Offline jvanick

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Re: How black is your film
« Reply #2 on: March 25, 2016, 08:08:04 AM »
the UV blockers in film ink/dye aren't necessarily black, so without a densitometer test of some sort to measure the actual UV blocking capabilities, you could be plenty 'blocking' and still have a film that you could 'sort-of' see through.

Offline Sbrem

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Re: How black is your film
« Reply #3 on: March 25, 2016, 08:27:24 AM »
Do you run one channel or "All Black"? We run just the one channel, black as real film that was tray developed... (just an expression, scientists hold your tongue...)

Steve
I made a mistake once; I thought I was wrong about something; I wasn't

Offline blue moon

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Re: How black is your film
« Reply #4 on: March 25, 2016, 08:56:12 AM »
can't help with the printer or RIP issues, not enough info was given.
As far as opacity, 3.0 Dmax seems to be a number most ppl will agree with. That means 99.9% of the light is blocked ether by a physical barrier or UV blocking agents. In our case 3.0 equals complete discoloration of the fluorescent fixtures we use. The light is visible, but it is so dim that no part of it is white (it takes on the blue ink hue) and the ends of the tubes are hard to see. If you are not having problems seeing the light, your films are probably to light. This is all negated with UV blockers though as mentioned by jvanick. They can let regular light through and block the UV spectrum so the films would not be as dark. My take is, if it's physically blocked there is no way for the light to get through and I can see what's going on. Since we can't see UV, unless I use UV dedicated meter (which we do not have, but have borrowed in the past) by having a physical layer I know for a fact that we are good.

pierre
Yes, we've won our share of awards, and yes, I've tested stuff and read the scientific papers, but ultimately take everything I say with more than just a grain of salt! So if you are looking for trouble, just do as I say or even better, do something I said years ago!

Offline Ryan

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Re: How black is your film
« Reply #5 on: March 25, 2016, 09:38:32 AM »
mine are see through. Never been able to get a good black. That being said, I have no idea what I am losing/holding in the lower and upper tones because most of my work is just blocks of spot colors and my screens still burn "fine". I would love for someone to figure out what my issue is, but I've never pursued it....one day maybe

Ryan

Offline jvanick

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Re: How black is your film
« Reply #6 on: March 25, 2016, 09:41:31 AM »
mine are see through. Never been able to get a good black. That being said, I have no idea what I am losing/holding in the lower and upper tones because most of my work is just blocks of spot colors and my screens still burn "fine". I would love for someone to figure out what my issue is, but I've never pursued it....one day maybe

Ryan

what printer and ink system?

film choice?

are you running a rip?

the combination of all 3 can cause that... but like you said, you're making good screens, so maybe it doesn't matter...

Offline Ryan

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Re: How black is your film
« Reply #7 on: March 25, 2016, 09:55:48 AM »
Wasatch  - Fixxons waterproof film   -  Epson 4880   ---   Using epson inks, not an all black system of any sort (thought I might print some nice pictures out it one day --- haha high hopes).  7pl dot size, if I go up ink pools

Offline Rockers

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Re: How black is your film
« Reply #8 on: March 25, 2016, 10:55:57 AM »
Sorry I should have been more precise to begin with.
Epson 4880
Wasatch SoftRip
AccuInk
AccuArt3
One channel black



Offline cbjamel

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Re: How black is your film
« Reply #9 on: March 25, 2016, 12:06:22 PM »
What I have found different times of the year you need more or less ink depending on humidity levels.
Shane

Offline Ryan

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Re: How black is your film
« Reply #10 on: March 25, 2016, 12:24:32 PM »
mine have always been the same since day 1, some 5-6 years ago (or whenever the 4880s came out)

Offline jsheridan

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Re: How black is your film
« Reply #11 on: March 25, 2016, 01:25:49 PM »
Wasatch  - Fixxons waterproof film   -  Epson 4880   ---   Using epson inks,

Stop using epson inks.. they are not uv blocking as they are meant to print on paper and make really pretty colored pictures, not opaque film.

Use a dye or pigment based ink that is designed for screen printing films.




Blacktop Graphics Screenprinting and Consulting Services

Offline ZooCity

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Re: How black is your film
« Reply #12 on: March 25, 2016, 02:23:48 PM »
What jsheridan said.  With good dye black ink (I like Chromaline's Accuink) and fixxons film on a 48XX series you should have films as dark as you like.  With the right res and RIP settings you can get closer to imagesetter quality than you might think provided you don't need your films to print out super fast and can settle with single head, uni directional printing. 

Alternately, you can order up some Epson's new Screen Positive Film which is designed to work with Epson Ultrachrome XD inks.  I imagine with all the options in your Wasatch rip you could tune if for the K3 inks in the 4880.  The nice part about doing this is you could print regular color prints from you epson.  I tested their product a few weeks ago and it seems like good stuff from what I saw but I have no experience using the Ultrachrome pigment inks on it.

Offline blue moon

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Re: How black is your film
« Reply #13 on: March 25, 2016, 02:39:04 PM »
'what John and Chris said!

pierre
Yes, we've won our share of awards, and yes, I've tested stuff and read the scientific papers, but ultimately take everything I say with more than just a grain of salt! So if you are looking for trouble, just do as I say or even better, do something I said years ago!

Offline Frog

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Re: How black is your film
« Reply #14 on: March 25, 2016, 02:52:43 PM »
Yep, even without a RIP, I get dense blacks (not like the sunglasses in the pic) with aftermarket Cobra pigment inks on films like Fixxons
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