QTR Beginning Questions

[MJF]

Hello everyone,

I am just getting started with the process of making digital negatives for Platinum/Palladium printing and after reading several posts and getting tons and tons of information about QTR for making the negatives, I still have a few very basic questions. My Epson 3800 is on the way and I can hardly wait to get started.

I very simple question to start with is about when you process the rgb file from your capture source, in my case a scan of a b&w negative processed in rgb, with photoshop, do you convert it to a grayscale file or keep it in rgb for QTR?

With the this model printer are there any special settings to the printer for making degital negatives?

What seems to be the normal period for someone to get up and running with QTR. I understand that it depends on past experience, but just getting started with the 3800 calibration, I was wondering what to expect.

I have already downloaded Ron Reeder's manual, curve, and step table.

Thanks for all your help, and it is good to find this forum.

mary

 

[Ron-san]

Hello everyone,

I very simple question to start with is about when you process the rgb file from your capture source, in my case a scan of a b&w negative processed in rgb, with photoshop, do you convert it to a grayscale file or keep it in rgb for QTR?

With the this model printer are there any special settings to the printer for making degital negatives?

What seems to be the normal period for someone to get up and running with QTR. I understand that it depends on past experience, but just getting started with the 3800 calibration, I was wondering what to expect.

I have already downloaded Ron Reeder's manual, curve, and step table.

mary

Mary--
In my experience trying to explain QTR and digital negs to others, the learning curve can vary from 30 minutes to infinity. However, since you will soon have a 3800 and I have posted a QTR profile for printing with palladium, I would hope your personal curve will not be too long. The published profile should at least allow you to start making prints, even if they are not perfect.

Yes indeed, there are specific printer settings that need to be used when printing negs with QTR. No way to abbreviate those, you have to read the manual where I hope they are all listed.

I know of no advantage of using an RGB file with QTR. I scan my B+W negs in 16 bit depth and immediately imbed gray gamma 1.8 in the image (because all my profiles are calibrated with a grayscale stepwedge that has gray gamma 1.8 embedded in it). Once the image has been edited it is flipped horizontally, inverted to negative, and sent to the printer to be printed using the appropraite QTR profile.

You have interesting days ahead, but I think the outcome will be worth the effort.

Cheers, Ron Reeder

 

[donbga]

Mary--
In my experience trying to explain QTR and digital negs to others, the learning curve can vary from 30 minutes to infinity. However, since you will soon have a 3800 and I have posted a QTR profile for printing with palladium, I would hope your personal curve will not be too long. The published profile should at least allow you to start making prints, even if they are not perfect.

Yes indeed, there are specific printer settings that need to be used when printing negs with QTR. No way to abbreviate those, you have to read the manual where I hope they are all listed.

I know of no advantage of using an RGB file with QTR. I scan my B+W negs in 16 bit depth and immediately imbed gray gamma 1.8 in the image (because all my profiles are calibrated with a grayscale stepwedge that has gray gamma 1.8 embedded in it). Once the image has been edited it is flipped horizontally, inverted to negative, and sent to the printer to be printed using the appropraite QTR profile.

You have interesting days ahead, but I think the outcome will be worth the effort.

Cheers, Ron Reeder

Ron,

Is your gray gamma set to 1.8 because you are using a Mac? Shouldn't Windows users use a gray gamma of 2.2?

Thanks,

Don Bryant

 

[Ron-san]

Ron,

Is your gray gamma set to 1.8 because you are using a Mac? Shouldn't Windows users use a gray gamma of 2.2?

Thanks,

Don Bryant

Don-- Yes, fundamentally it is set to 1.8 because I am using a Mac. If you want to use gamma 2.2, however, you should use gamma 2.2 throughout your entire workflow. Your computer screen should be set to gamma 2.2 and the step wedge you use to calibrate your digital negatives should have gamma 2.2 embedded in it.
When I use the Photoshop eyedropper to read the % gray values of my calibration step tablet, I want it to read the same % gray as is written on the a particular step. And I want to be certain that when I read a gray value from an image file that it is the same as what is on the calibration step tablet. So, I think it is important to be consistent with the same gamma throughout your entire workflow. Nothing particularly sacred about gamma 1.8, but consistency is sacred. Cheers, Ron Reeder

 

[donbga]

Don--

Yes, fundamentally it is set to 1.8 because I am using a Mac. If you want to use gamma 2.2, however, you should use gamma 2.2 throughout your entire workflow. Your computer screen should be set to gamma 2.2 and the step wedge you use to calibrate your digital negatives should have gamma 2.2 embedded in it.

Correct!

When I use the Photoshop eyedropper to read the % gray values of my calibration step tablet, I want it to read the same % gray as is written on the a particular step. And I want to be certain that when I read a gray value from an image file that it is the same as what is on the calibration step tablet. So, I think it is important to be consistent with the same gamma throughout your entire workflow.

RIght, I follow that.

Nothing particularly sacred about gamma 1.8,

Well for display gamma Windows users should have their monitors calibrated and profile to 2.2. Hence my question. Also I use Gray Gamma 2.2 for PS editing gray scale files.

I think it;s easy to get confused about these issues since most of us don't keep them in mind most of the time.

Thanks,

Don

 

[MJF]

Well, I finally got the QTR up and running, but I am having trouble with CS3 saving the curve .acv file. It will not give me the optons of saving that file type, seems to like .psd and .tiff. I had to finally add the information by hand, but would like to know how to do this on a windows machine.
Thanks.
Mary

 

[sanking]

Mary,

You can save the .acv curve with CS3. After adjusting the curve to what you want look at the top of the dialog box. At the top of the box, between the Preset box and OK, you will see a small box. Click on this box and it will give you the option of loading or saving an .acv file.

Doing this in CS and CS2 was much easier as there was a Save box. The Photoshop guys almost outdid themselves in stupidity in hiding the load/save box the way they did in CS3.

I am on a MAC but assume you have the same dialog boxes in the adjust curve menu.

Sandy King

Well, I finally got the QTR up and running, but I am having trouble with CS3 saving the curve .acv file. It will not give me the optons of saving that file type, seems to like .psd and .tiff. I had to finally add the information by hand, but would like to know how to do this on a windows machine.
Thanks.
Mary