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2006-03-23 by joejx8
Hi, I am intended to buy an old/used densitometer. I have seen a model which seems to measure only R,G,B *density*. Is there a mean to get a BW *density* value (by calculation) from R,G,B density values... I was thinking at a formula like DBW= 0,7*DR + 0,2*DG + 0,1*DB (values are just for illustration) ? Thanks ! J.
2006-03-23 by dlruckus
Hi Joe. You could just use the Green density readings as a relative measure of B&W K by using a Density to Lab_L* formula as given here by S Kale recently. Search on the words Kale,Excell and Density to find his post. The results would not be exhaustively accurate but should suffice for most needs. Regards Duane --- In DigitalBlackandWhiteThePrint@yahoogroups.com, "joejx8" <joejx8@...> wrote:
> > > Hi, > > I am intended to buy an old/used densitometer. I have seen a model > which seems to measure only R,G,B *density*. > > Is there a mean to get a BW *density* value (by calculation) from R,G,B > density values... I was thinking at a formula like DBW= 0,7*DR + 0,2*DG > + 0,1*DB (values are just for illustration) ? > > Thanks ! > > J. >
2006-03-23 by Robert Whitehouse
You could always just calibrate it by using it on a BW target with known density? _____
From: DigitalBlackandWhiteThePrint@yahoogroups.com [mailto:DigitalBlackandWhiteThePrint@yahoogroups.com] On Behalf Of joejx8 Sent: 23 March 2006 10:13 To: DigitalBlackandWhiteThePrint@yahoogroups.com Subject: [Digital BW] Converting RGB density readings into BW density readings Hi, I am intended to buy an old/used densitometer. I have seen a model which seems to measure only R,G,B *density*. Is there a mean to get a BW *density* value (by calculation) from R,G,B density values... I was thinking at a formula like DBW= 0,7*DR + 0,2*DG + 0,1*DB (values are just for illustration) ? Thanks ! J. Please visit the Group Homepage to check the Files, and other resources as they are often being updated. HYPERLINK "http://groups.yahoo.com/group/DigitalBlackandWhiteThePrint"http://groups.ya hoo.com/group/DigitalBlackandWhiteThePrint If you wish to receive no emails or just a daily digest, or you wish to unsubscribe, please edit your Membership preferences by visiting this same page. Please follow these basic guidelines: - As threads develop, trim off excess portions of earlier messages to keep them short. - Good manners are required at all time. No personal attacks or flames. Hostile, aggressive or argumentative users may be removed from the membership without notice. - Keep your posts and threads related to the group topic of digital B&W printing. Users who persistently make off-topic posts may be removed from the membership. - By posting on this forum you agree to abide by the group rules and guidelines, and to abide by the actions and decisions of the group Owner and Moderators. See �Group Topic, Rules and Guidelines� in the Files section: HYPERLINK "http://groups.yahoo.com/group/DigitalBlackandWhiteThePrint/files/"http://gr oups.yahoo.com/group/DigitalBlackandWhiteThePrint/files/ BY PARTICIPATING IN AND/OR POSTING MESSAGES TO THE DIGITAL BW, THE PRINT YAHOO! GROUP YOU EXPRESSLY UNDERSTAND AND AGREE THAT THE �OWNER� AND �MODERATORS� OF DIGITAL BW, THE PRINT YAHOO GROUP SHALL NOT BE LIABLE TO YOU FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, CONSEQUENTIAL OR EXEMPLARY DAMAGES, INCLUDING BUT NOT LIMITED TO, DAMAGES FOR LOSS OF PROFITS, GOODWILL, USE, DATA OR OTHER INTANGIBLE LOSSES (EVEN IF THE �OWNER� AND �MODERATORS� OF DIGITAL BW, THE PRINT YAHOO GROUP HAVE BEEN ADVISED OF THE POSSIBILITY OF SUCH DAMAGES), RESULTING FROM: (i) THE USE OR THE INABILITY TO USE THE DIGITAL BW, THE PRINT YAHOO GROUP; (ii) UNAUTHORIZED ACCESS TO OR ALTERATION OF YOUR TRANSMISSIONS OR DATA; (iii) STATEMENTS OR CONDUCT OF ANY THIRD PARTY ON THE DIGITAL BW, THE PRINT YAHOO GROUP; OR (iv) ANY OTHER MATTER RELATING TO THE DIGITAL BW, THE PRINT YAHOO GROUP. _____ YAHOO! GROUPS LINKS * Visit your group "HYPERLINK "http://groups.yahoo.com/group/DigitalBlackandWhiteThePrint"DigitalBlackandW hiteThePrint" on the web. * To unsubscribe from this group, send an email to: HYPERLINK "mailto:DigitalBlackandWhiteThePrint-unsubscribe@yahoogroups.com?subject=Uns ubscribe"DigitalBlackandWhiteThePrint-unsubscribe@yahoogroups.com * Your use of Yahoo! Groups is subject to the HYPERLINK "http://docs.yahoo.com/info/terms/"Yahoo! Terms of Service. _____ -- No virus found in this incoming message. Checked by AVG Free Edition. Version: 7.1.385 / Virus Database: 268.2.6/286 - Release Date: 20/03/2006 -- No virus found in this outgoing message. Checked by AVG Free Edition. Version: 7.1.385 / Virus Database: 268.2.6/286 - Release Date: 20/03/2006 [Non-text portions of this message have been removed]
2006-03-23 by joejx8
Hi Bob, That's a great great idea :-). I just have to find one BW target ..... Do you know if someone (kodak,...) manufacture such BW targets ? Thanks again for your idea ! J. --- In DigitalBlackandWhiteThePrint@yahoogroups.com, "Robert Whitehouse" <bob.whitehouse@...> wrote: > > You could always just calibrate it by using it on a BW target with known > density? > > > _____ > > From: DigitalBlackandWhiteThePrint@yahoogroups.com > [mailto:DigitalBlackandWhiteThePrint@yahoogroups.com] On Behalf Of joejx8 > Sent: 23 March 2006 10:13 > To: DigitalBlackandWhiteThePrint@yahoogroups.com > Subject: [Digital BW] Converting RGB density readings into BW density > readings > > > > Hi, > > I am intended to buy an old/used densitometer. I have seen a model > which seems to measure only R,G,B *density*. > > Is there a mean to get a BW *density* value (by calculation) from R,G,B > density values... I was thinking at a formula like DBW= 0,7*DR + 0,2*DG > + 0,1*DB (values are just for illustration) ? > > Thanks ! > > J. > > > > > > > > Please visit the Group Homepage to check the Files, and other resources as > they are often being updated. > > HYPERLINK > "http://groups.yahoo.com/group/DigitalBlackandWhiteThePrint"http://g roups.ya > hoo.com/group/DigitalBlackandWhiteThePrint > > If you wish to receive no emails or just a daily digest, or you wish to > unsubscribe, please edit your Membership preferences by visiting this same > page. > > Please follow these basic guidelines: > - As threads develop, trim off excess portions of earlier messages to keep > them short. > - Good manners are required at all time. No personal attacks or flames. > Hostile, aggressive or argumentative users may be removed from the > membership without notice. > - Keep your posts and threads related to the group topic of digital B&W > printing. Users who persistently make off-topic posts may be removed from > the membership. > - By posting on this forum you agree to abide by the group rules and > guidelines, and to abide by the actions and decisions of the group Owner and > Moderators. See "Group Topic, Rules and Guidelines" in the Files section: > HYPERLINK > "http://groups.yahoo.com/group/DigitalBlackandWhiteThePrint/files/"h ttp://gr > oups.yahoo.com/group/DigitalBlackandWhiteThePrint/files/ > > BY PARTICIPATING IN AND/OR POSTING MESSAGES TO THE DIGITAL BW, THE PRINT > YAHOO! GROUP YOU EXPRESSLY UNDERSTAND AND AGREE THAT THE "OWNER" AND > "MODERATORS" OF DIGITAL BW, THE PRINT YAHOO GROUP SHALL NOT BE LIABLE TO YOU > FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, CONSEQUENTIAL OR EXEMPLARY > DAMAGES, INCLUDING BUT NOT LIMITED TO, DAMAGES FOR LOSS OF PROFITS, > GOODWILL, USE, DATA OR OTHER INTANGIBLE LOSSES (EVEN IF THE "OWNER" AND > "MODERATORS" OF DIGITAL BW, THE PRINT YAHOO GROUP HAVE BEEN ADVISED OF THE > POSSIBILITY OF SUCH DAMAGES), RESULTING FROM: (i) THE USE OR THE INABILITY > TO USE THE DIGITAL BW, THE PRINT YAHOO GROUP; (ii) UNAUTHORIZED ACCESS TO OR > ALTERATION OF YOUR TRANSMISSIONS OR DATA; (iii) STATEMENTS OR CONDUCT OF ANY > THIRD PARTY ON THE DIGITAL BW, THE PRINT YAHOO GROUP; OR (iv) ANY OTHER > MATTER RELATING TO THE DIGITAL BW, THE PRINT YAHOO GROUP. > > > > > _____ > > YAHOO! GROUPS LINKS > > > > * Visit your group "HYPERLINK > "http://groups.yahoo.com/group/DigitalBlackandWhiteThePrint"DigitalB lackandW > hiteThePrint" on the web. > > > * To unsubscribe from this group, send an email to: > HYPERLINK > "mailto:DigitalBlackandWhiteThePrint-unsubscribe@yahoogroups.com? subject=Uns > ubscribe"DigitalBlackandWhiteThePrint-unsubscribe@yahoogroups.com > > > * Your use of Yahoo! Groups is subject to the HYPERLINK > "http://docs.yahoo.com/info/terms/"Yahoo! Terms of Service. > > > _____ > > > > -- > No virus found in this incoming message. > Checked by AVG Free Edition. > Version: 7.1.385 / Virus Database: 268.2.6/286 - Release Date: 20/03/2006 > > > > -- > No virus found in this outgoing message. > Checked by AVG Free Edition. > Version: 7.1.385 / Virus Database: 268.2.6/286 - Release Date: 20/03/2006
> > > > [Non-text portions of this message have been removed] >
2006-03-23 by joejx8
Hi Duane, Thank you very much for your reply :) I have found several calculators: kale's one: http://www.brucelindbloom.com/index.html?CompandCalculator.html and: http://www.colorpro.com/info/tools/convert.htm http://www.forret.com/tools/color.asp But I don't really know how to use them regarding my need... J. --- In DigitalBlackandWhiteThePrint@yahoogroups.com, "dlruckus" <dlruckus@...> wrote: > > Hi Joe. > You could just use the Green density readings as a relative measure > of B&W K by using a Density to Lab_L* formula as given here by S Kale > recently. Search on the words Kale,Excell and Density to find his post. > The results would not be exhaustively accurate but should suffice for > most needs. > > Regards > Duane > > > > > --- In DigitalBlackandWhiteThePrint@yahoogroups.com, "joejx8" > <joejx8@> wrote: > > > > > > Hi, > > > > I am intended to buy an old/used densitometer. I have seen a model > > which seems to measure only R,G,B *density*. > > > > Is there a mean to get a BW *density* value (by calculation) from R,G,B > > density values... I was thinking at a formula like DBW= 0,7*DR + 0,2*DG
> > + 0,1*DB (values are just for illustration) ? > > > > Thanks ! > > > > J. > > >
2006-03-23 by Helen Bach
An amber Wratten 106 is used as the 'visual' filter in Macbeth densitometers (and maybe others) to make the spectral response of the sensor simulate that of the eye. The 106 allows almost all the red, some green and a little blue through. However, that in itself isn't enough information without knowing the spectral characteristics of everything else. I just did a few quick tests on the Status A RGB and Visual density data I have readily available, and I go a reasonable match when Dvis = 0.3*R + 0.55*G + 0.15*B That doesn't mean that it is correct, just that it might be close enough in the absence of better information. Depending on where you are, why not look around for a cheap densitometer that has a visual channel, or better still, buy a PrintFix Pro on eBay. Best, Helen --- In DigitalBlackandWhiteThePrint@yahoogroups.com, "joejx8" <joejx8@...> wrote:
> > > Hi, > > I am intended to buy an old/used densitometer. I have seen a model > which seems to measure only R,G,B *density*. > > Is there a mean to get a BW *density* value (by calculation) from R,G,B > density values... I was thinking at a formula like DBW= 0,7*DR + 0,2*DG > + 0,1*DB (values are just for illustration) ? > > Thanks ! > > J. >
2006-03-24 by joejx8
Hi Helen, Thank you so much for your detailled answer. I found two formula for converting Y / RGB: Y=0.299*R + 0.587*G + 0.114*B Y=0.222*R + 0.707*G + 0.071*B Seems that the first one match your's. Did you get your formula from few or many (Y,R,G,B) values ? I have looked à PrintFix pro. Very interesting but still too expensive for my need (about $500) :) Thanks again ! J. --- In DigitalBlackandWhiteThePrint@yahoogroups.com, "Helen Bach" <helenbach@...> wrote: > > An amber Wratten 106 is used as the 'visual' filter in Macbeth > densitometers (and maybe others) to make the spectral response of the > sensor simulate that of the eye. The 106 allows almost all the red, > some green and a little blue through. However, that in itself isn't > enough information without knowing the spectral characteristics of > everything else. > > I just did a few quick tests on the Status A RGB and Visual density > data I have readily available, and I go a reasonable match when > > Dvis = 0.3*R + 0.55*G + 0.15*B > > That doesn't mean that it is correct, just that it might be close > enough in the absence of better information. > > Depending on where you are, why not look around for a cheap > densitometer that has a visual channel, or better still, buy a > PrintFix Pro on eBay. > > Best, > Helen > > --- In DigitalBlackandWhiteThePrint@yahoogroups.com, "joejx8" > <joejx8@> wrote: > > > > > > Hi, > > > > I am intended to buy an old/used densitometer. I have seen a model > > which seems to measure only R,G,B *density*. > > > > Is there a mean to get a BW *density* value (by calculation) from R,G,B > > density values... I was thinking at a formula like DBW= 0,7*DR + 0,2*DG
> > + 0,1*DB (values are just for illustration) ? > > > > Thanks ! > > > > J. > > >
2006-03-24 by Helen Bach
Hi, I used about thirty sets of readings from a Macbeth TR924. I'll try the second formula on them when I get the chance. I bought my PFP on eBay. It was $400 including shipping, and it was delivered the day after I won it. Best, Helen --- In DigitalBlackandWhiteThePrint@yahoogroups.com, "joejx8" <joejx8@...> wrote:
> > > Hi Helen, > > Thank you so much for your detailled answer. > > I found two formula for converting Y / RGB: > > Y=0.299*R + 0.587*G + 0.114*B > Y=0.222*R + 0.707*G + 0.071*B > > Seems that the first one match your's. Did you get your formula from > few or many (Y,R,G,B) values ? > > I have looked à PrintFix pro. Very interesting but still too > expensive for my need (about $500) :) > > Thanks again ! > > J.
2006-03-24 by John Vitollo
--- In DigitalBlackandWhiteThePrint@yahoogroups.com, "Helen Bach" <helenbach@...> > I used about thirty sets of readings from a Macbeth TR924. I'll try > the second formula on them when I get the chance. > I bought my PFP on eBay. It was $400 including shipping, and it was > delivered the day after I won it. Helen, You have the beta software for PFP that reads LAB and Density? Contact CDTobie if not. Best, John V.
2006-03-25 by Steve and Ann Taylor
Hi, I asked this question over on the QTR group but haven't gotten a reply so I thought I'd ask here, too. It seems like there is a lot of overlap of members, but maybe somebody will see it here. I tried QTR quite a while ago and got frustrated with trying to get it working. Now I just downloaded the most recent version and am going to give it another try. My problem is that up until now, all my photo editing work has been on my Win98SE computer. That is where my scanner, printer (Epson 2200), and software all reside. I have loaded QTR on another computer that is running Win2000. When I tried this before, there was a place to tell the software that it should print to a network printer. My 2200 is set to share as QUAD2200 on the Win98 machine but the new QTRgui doesn't find it when it starts up. With the old QTR software, I did manage to get it to print over the network but I was having a lot of trouble with it printing just parts of the image in various places on the paper. The images looked great as far as tone but I could never get a complete image on a sheet. I gave up. I have been using the Epson Gray Balancer program and that has made by B&W prints on the 2200 come out pretty nice. I am hoping that with the QTR they can be even better. So, how can I get QTR to recognize my 2200 on the network? Thanks, Steve Taylor -- Using M2, Opera's revolutionary e-mail client: http://www.opera.com/m2/
2006-03-26 by joejx8
Hi Helen, Thank you for your reply :) I wish I've known about PFP before I bought my old Xrite 880 densitometer. I should try first to use this densitometer, get results, determine my needs. PFP is a great value device. Best regard, J. --- In DigitalBlackandWhiteThePrint@yahoogroups.com, "Helen Bach" <helenbach@...> wrote: > > Hi, > > I used about thirty sets of readings from a Macbeth TR924. I'll try > the second formula on them when I get the chance. > > I bought my PFP on eBay. It was $400 including shipping, and it was > delivered the day after I won it. > > Best, > Helen > > --- In DigitalBlackandWhiteThePrint@yahoogroups.com, "joejx8" > <joejx8@> wrote: > > > > > > Hi Helen, > > > > Thank you so much for your detailled answer. > > > > I found two formula for converting Y / RGB: > > > > Y=0.299*R + 0.587*G + 0.114*B > > Y=0.222*R + 0.707*G + 0.071*B > > > > Seems that the first one match your's. Did you get your formula from
> > few or many (Y,R,G,B) values ? > > > > I have looked à PrintFix pro. Very interesting but still too > > expensive for my need (about $500) :) > > > > Thanks again ! > > > > J. >