A Photography forum. PhotoBanter.com

If this is your first visit, be sure to check out the FAQ by clicking the link above. You may have to register before you can post: click the register link above to proceed. To start viewing messages, select the forum that you want to visit from the selection below.

Go Back   Home » PhotoBanter.com forum » General Photography » In The Darkroom
Site Map Home Register Authors List Search Today's Posts Mark Forums Read Web Partners

black and white inks for making digital negatives/prints?



 
 
Thread Tools Display Modes
  #21  
Old October 27th 09, 07:24 PM posted to rec.photo.darkroom
David Nebenzahl
external usenet poster
 
Posts: 1,353
Default black and white inks for making digital negatives/prints?

On 10/27/2009 6:09 AM Lew spake thus:

You still have more or less full access to the usenet through Google
groups and, possible, Yahoo.


Thanks but no thanks. I'd rather not post or read at all than use
Google's ill-conceived brain-damaged spam portal.


--
Found--the gene that causes belief in genetic determinism
  #22  
Old October 28th 09, 03:43 AM posted to alt.comp.periphs.printers,rec.photo.darkroom,rec.photo.digital
Me
external usenet poster
 
Posts: 796
Default black and white inks for making digital negatives/prints?

John Navas wrote:
On Sun, 25 Oct 2009 08:21:00 -0700, "Don Schmidt" Don
red_1987 wrote in
isition:

"Matt Clara" wrote in message
...
I know it's possible to purchase "B&W" inks comprised of black with shades
of gray to replace the Cc,M,Y, cartridges in my old Epson 1270, but I don't
know where to buy inks with a good reputation for this purpose.


That's a new one to me; my inkjet printer produces shades of gray by the
amount of black it uses to cover the area being printed, no matter how small
the area.
(The white is the paper being printed on)


Gray inks produce a much superior result for critical work.
For more information, see
http://www.normankoren.com/makingfineprints4.html

They're not "grey" inks.
They're often called light-black and light-light black etc.
They are weaker (diluted) versions of black ink.
For the higher end inkjet photo printers carbon black pigments are used.
Problem with carbon black and other "black" pigments is that they
aren't black - they're usually a very very dark brown. So when they're
applied at low density, they don't look very black. To overcome that,
they add a blue/violet pigment (sometimes a dye) to make the black
neutral when applied at different densities. They do the same with
black for 4-colour (and more) litho press printing inks. All good so
far, but carbon black and the available lightfast dark blue pigments had
stability problems when used together in low viscosity aqueous
formulations, and blue dye faded too fast for archival inks.
AFAIK the first inkjet ink formulations to overcome this were Epson
Ultrachrome K3 inks, with three "strengths" of black. The data
explaining this together with example formulations is all there in US
patents.
So with neutral (or very close to neutral) at different densities,
smooth tonality was limited by minimum droplet size, so having the
ability to apply same minimum sized droplets of progressively "weaker"
ink is an advantage, and bound to be more neutral than using CYM colours
to achieve this. But some C,Y&M is still used with "neutral" black inks
- it's not perfect, Droplet size isn't fixed, Epson Piezo heads can
vary droplet size by varying amplitude and waveform of the signal (IIRC
8 sizes) HP have different sized thermal nozzles, so many more nozzles
per head, and Canon are in-between, by having several different sized
thermal elements driving each nozzle.
The results are good. You can still see the droplets with a loupe. I
can't with naked eye.
 




Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

vB code is On
Smilies are On
[IMG] code is Off
HTML code is Off
Forum Jump

Similar Threads
Thread Thread Starter Forum Replies Last Post
Inks, paper for archival prints of digital images? Bert Hyman Digital Photography 3 April 24th 07 02:53 AM
Digital prints from negatives Norm Fleming 35mm Photo Equipment 58 October 31st 06 03:05 AM
Nikon Coolscan V ED and Black&White negatives Hoshisato Digital Photography 49 August 3rd 06 12:07 AM
spotting black and white prints [email protected] In The Darkroom 15 November 15th 05 03:10 AM
Making 35mm negatives from 16mm or 110 colour negatives [email protected] General Photography Techniques 3 March 1st 05 07:43 PM


All times are GMT +1. The time now is 11:07 PM.


Powered by vBulletin® Version 3.6.4
Copyright ©2000 - 2024, Jelsoft Enterprises Ltd.
Copyright ©2004-2024 PhotoBanter.com.
The comments are property of their posters.