exposing paper

[algarzai]

guys,
i am planning to build a darkroom now that i have more space in my house. My experience in development is nothing more that 4 years of developing BW film, E6 & C41 in jobo cpp and daylight tanks. I try to minimize variables. I resist temptation to try new developers because i don't have time, or patience. I have a day job that is a little more than full time and run an art gallery/print & framing shop. and most importantly i have a family.

I was printing positives on transparent media for a customer. I am intrigued by the possibilities. So i want to try digital negatives out on BW paper. I am currently reading about making digital negatives. on the other hand, I have never printed on photo paper. I am always discouraged by the amount of trial and error. i find printing a test strip a waste of time and money.

so my question, why can't exposure be determined the same way film is? enlarge the photo, put a light meter at certain locations on the print then calculate exposure. the same process you do with a spot meter. can it be done? and what equipment would i need? kindly say how it could be done.

[Jim Jones]

A variety of enlarging meters are available to do as you hinted. Some are very basic, and require expertise just like a basic meter for photography. Others should let one make an accurate exposure on the first try. Google for enlarging meter for more information.

[algarzai]

great..
anyting you have tried before? i think i like the ones made by darkroomautomation.com


A variety of enlarging meters are available to do as you hinted. Some are very basic, and require expertise just like a basic meter for photography. Others should let one make an accurate exposure on the first try. Google for enlarging meter for more information.

[Jim Noel]

Even with meters designed to assist with getting correct exposure,you still need test strips. One sheet of paper used correctly as a test strip will provide exposure and contrast information quickly and easily. the test strip is the printers friend.

[ROL]

i find printing a test strip a waste of time and money.

Making physical prints by classical means is, or can be, so much more than discrete measurement. You may want to have a look at this (http://www.rangeoflightphotography.com/pages/making-a-fine-art-print).

[algarzai]

there it is.. 3 prints to achieve the desired result with a steep learning curve. Chemicals, paper, notes, questionable repeatability (skill) = all equals time and money. this is exactly what i am trying to avoid.
you might think i am naive for thinking about darkroom printing with high success without putting effort in it. There are other ways to achieve the same end. I haven't verified if it will produce similar quality .. yet. but it is certainly easier and more economical in my case. digital negatives and contact printing. silver gelatin is a step towards many possibilities for me. but i have to start somewhere and silver gelatin is where i am going to start.
having got a digital negative at the desired size photoshopped in whatever way i please. with command Z in action lol. i think i want to achieve a straight print that works. i will achieve that by printing a few test strips of wedges and fine tune a photoshop curve. then standardize that. the only variable is light source. if i am able to find a tool that helps me figure that out, my problem would be solved..

beware: this is all theory that i heard works :)


Making physical prints by classical means is, or can be, so much more than discrete measurement. You may want to have a look at this (http://www.rangeoflightphotography.com/pages/making-a-fine-art-print).

[ROL]

you might think i am naive for thinking about darkroom printing with high success without putting effort in it.

No, certainly, I no longer think that. :rolleyes:

[algarzai]

Lol. It's worth a shot. Some experimentation in the beginning then it should work fine with repeatable and predictable results.

naive
nʌɪˈiːv,nɑːˈiːv/
adjective
(of a person or action) showing a lack of experience, wisdom, or judgement.

I certainly don't have experience. I am sharing this with the forum to hear from experienced people like yourself.


No, certainly, I no longer think that. :rolleyes:

[ataim]

I have an ilford em10. I make an 8x10 proof eack negative it helps to get with 1/2 stop of correct exposure. Good enough to evaluate what I have

[ic-racer]

Page 8 of this : http://www.125px.com/docs/manuals/darkroom/beseler/Beseler_PM2L_Manual.pdf

[algarzai]

Thanks Paul. this looks simple to use. although 1/2 a stop is a little too much...

I have an ilford em10. I make an 8x10 proof eack negative it helps to get with 1/2 stop of correct exposure. Good enough to evaluate what I have

this is good. do you have experience using it? better than half a stop error? why aren't people using it?

Page 8 of this : http://www.125px.com/docs/manuals/darkroom/beseler/Beseler_PM2L_Manual.pdf

[ataim]

Algarzai,

When I typed that I was on my phone. WIth a keyboard I can explain a little better. I use the EM10 as a tool to be able to rapidly print all of my 4x5 and 8x10 negatives into a 8x10 proof for filing and reference. The statement of 1/2 stop gets me close enough to determine if I want to further mess with that negative. IMHO nothing can take place of test strips to nail down an exposure and contrast. I also use it to estimate times when going from an 8x10 proof to a 16x20 or larger print.

[algarzai]

thanks for the info Paul. i really appreciate you coming back to fill in the missing information. :)


Algarzai,

When I typed that I was on my phone. WIth a keyboard I can explain a little better. I use the EM10 as a tool to be able to rapidly print all of my 4x5 and 8x10 negatives into a 8x10 proof for filing and reference. The statement of 1/2 stop gets me close enough to determine if I want to further mess with that negative. IMHO nothing can take place of test strips to nail down an exposure and contrast. I also use it to estimate times when going from an 8x10 proof to a 16x20 or larger print.

[Jim Jones]

The EM10 is one of many adequate tools for making a good test print. That print will indicate any slight changes necessary in exposure and contrast. More important, it should indicate where dodging and burning are required for the best possible print. With experience, one can dispense with a meter or test print and usually make the first print satisfactory for some purposes. However, the fine print might require as much thought and perhaps as much time as a good painting. That's what makes it fine. For an example, go to post #5 at http://www.largeformatphotography.info/forum/showthread.php?114177-Print-technique-Subtle-tweaks-going-round-and-round

[ROL]

However, the fine print might require as much thought and perhaps as much time as a good painting. That's what makes it fine.[/URL]

That was my entire point in presenting a link within my initial post to the OP. I will admit to its subtlety, but the idea, apparently lost on the OP, was that making anything other than straight test prints is much more than evaluation of discrete technical measurements.

[algarzai]

That was my entire point in presenting a link within my initial post to the OP. I will admit to its subtlety, but the idea, apparently lost on the OP, was that making anything other than straight test prints is much more than evaluation of discrete technical measurements.


The EM10 is one of many adequate tools for making a good test print. That print will indicate any slight changes necessary in exposure and contrast. More important, it should indicate where dodging and burning are required for the best possible print. With experience, one can dispense with a meter or test print and usually make the first print satisfactory for some purposes. However, the fine print might require as much thought and perhaps as much time as a good painting. That's what makes it fine. For an example, go to post #5 at http://www.largeformatphotography.info/forum/showthread.php?114177-Print-technique-Subtle-tweaks-going-round-and-round


I appreciate your tries to tell me that a print is something the needs tries, time, and effort to perfectly achieve a true artistic intent. I perfectly understand that.

What I am saying is. I am going to do that on a screen on Photoshop. Then do a digital negative. Having spent the time on Photoshop and examined the result on screen, I need to contact print it on paper. Having done all my dodging and burning and whatever else I wanted to do on photoshop. I just need to have a good exposure which is the subject of this post.

Is it clear?

[Huub]

Tho i don't have any experience going this road i would give it a try. The critical thing will be to match the contrast and density of your digital negatives to the paper you are going to work with. A good negative should match the contrast curves of the paper and the density should be so that every negative should need the same exposure time. Once you have figured that out you should keep the output of your printer constant. What you would ideally want to achieve is that every print needs the exact same exposure and filter settings on your enlarger, given a certain print size. It will be some trial and error to get to this point, but once there things should work out nicely for all your prints i guess.

A thing i ask myself is if you want to enlarge your digital negatives or if you are going the contact printing way. The first way will ask a lot more of the quality of your printed negative and at least a decent enlarger and lens, the second will ask a big printer if you want to do large prints, but you can suffice with a light source that gives a constant and even output and a contact printing frame.

[algarzai]

Tho i don't have any experience going this road i would give it a try. The critical thing will be to match the contrast and density of your digital negatives to the paper you are going to work with. A good negative should match the contrast curves of the paper and the density should be so that every negative should need the same exposure time. Once you have figured that out you should keep the output of your printer constant. What you would ideally want to achieve is that every print needs the exact same exposure and filter settings on your enlarger, given a certain print size. It will be some trial and error to get to this point, but once there things should work out nicely for all your prints i guess.

A thing i ask myself is if you want to enlarge your digital negatives or if you are going the contact printing way. The first way will ask a lot more of the quality of your printed negative and at least a decent enlarger and lens, the second will ask a big printer if you want to do large prints, but you can suffice with a light source that gives a constant and even output and a contact printing frame.

That's the plan. My only question is how do I measure the light hitting the paper and figure out exposure. The guys have proposed a couple of devices.

I have a 64 inches printer in my print shop. I also have a couple of 44 inches printers. I plan on printing large negative. I don't know if this will give better results as compared to enlarged originals. I am guessing I will be get better quality at large sizes. The lower the analog enlargement is the better the quality I would get with analog.
I cannot compare grain vs half tone dot. But I think the bigger the print the more half tone dots required to draw it. This is all theory...

Anyhow, I don't have a large enlarger. I also don't have skills as a darkroom printers at this point. I don't want to end up with gelatin silver prints. I want to practice this method and perfect digital negatives for all the possibilities it brings me and my customers.

[jp]

You want to try darkroom printing, but don't want to end up with gelatin silver prints? What are you after then, an alt process? For that you'd want digital negatives. For silver prints, with a tiny bit of experience it's easy to use test strips to fine tune contrast and exposure. Need a little more contrast? Turn the magenta dial on the enlarger or use a different filter; no need to reprint a negative. It's really pretty simple once you get the hang of it. For alt process stuff, you can indeed make curve "profiles" like digital negative books describe as that can be harder to control contrast / density, etc..

[Huub]

I am not sure what you want to achieve, but it looks like you are pretty well set up for contact printing from an digital negative. When using classic photograpic paper you will end up with a silver gelating print tho.

What you need to achieve this is a light source that gives a constant and even spread of light over the maximum size of the negatives you want to expose, a sheet of glass large enough to cover the negative and sheet of paper, trays and chemicals to develop the paper. And a darkroom of course.

When you don't change the place of your light source relative to the paper and negative you want to expose and if the output of your power source is constant enough so there is no variation in the light output, the time you have to expose the negative and paper should be indendent of your size of paper and negative. There will be only two variables left: the density and contrast of your negative and the kind of paper you want to use. The denisity of your negative is set digitally by yourself, the curves and sensitivity of your paper is set by the manifacturer. A manufacturer like Ilford has excelent quality control and a given type of paper will have almost the same characteristics, independent of size and emulsion number.

There are a few devices to measure the output of your light source to match it to a certain paper. The Ilford thing mentioned earlier is one of these, the stopclock from RH design is another. Thing is that you have to calibrate these devices to the characteristics of the papers you want to use. This will costs you a few sheets of the given paper and about an hour or so work for each paper you want to use. This is about the same amount of effort it will cost you to figure out the exposure time for contact printing the classical way, using test strips.

So my idea would be to invest a few days of work to figure out if this works out for you, using a box of 8x10 paper of the quality of paper you are likely going to use. When it works out, you can upscale it without much effort. And when it doesn't: it was a good learning moment.

[Tim Meisburger]

I don't think you need to measure the light. If the print looks right on your computer, and you figure out one time the correct exposure to reproduce that on paper, then every time for every print you will get it right on the computer, print your digital negative, the give that your standard exposure. The density of the digital negative will be determined by your digital manipulations on the computer so the same exposure will give you the correct print every time. I think (but what do I know).

[algarzai]

That's the plan. My only question is how do I measure the light hitting the paper and figure out exposure. The guys have proposed a couple of devices.

I have a 64 inches printer in my print shop. I also have a couple of 44 inches printers. I plan on printing large negative. I don't know if this will give better results as compared to enlarged originals. I am guessing I will be get better quality at large sizes. The lower the analog enlargement is the better the quality I would get with analog.
I cannot compare grain vs half tone dot. But I think the bigger the print the more half tone dots required to draw it. This is all theory...

Anyhow, I don't have a large enlarger. I also don't have skills as a darkroom printers at this point. I don't want to end up with gelatin silver prints. I want to practice this method and perfect digital negatives for all the possibilities it brings me and my customers.


You want to try darkroom printing, but don't want to end up with gelatin silver prints? What are you after then, an alt process? For that you'd want digital negatives. For silver prints, with a tiny bit of experience it's easy to use test strips to fine tune contrast and exposure. Need a little more contrast? Turn the magenta dial on the enlarger or use a different filter; no need to reprint a negative. It's really pretty simple once you get the hang of it. For alt process stuff, you can indeed make curve "profiles" like digital negative books describe as that can be harder to control contrast / density, etc..

yes i am after palladium and carbon printing from digital files (scanned or original). It is easier to start with silver gelatin prints until i get a hang of digital negative making and i get it reproducible with the least amount of trail and error.


I am not sure what you want to achieve, but it looks like you are pretty well set up for contact printing from an digital negative. When using classic photograpic paper you will end up with a silver gelating print tho.

What you need to achieve this is a light source that gives a constant and even spread of light over the maximum size of the negatives you want to expose, a sheet of glass large enough to cover the negative and sheet of paper, trays and chemicals to develop the paper. And a darkroom of course.

When you don't change the place of your light source relative to the paper and negative you want to expose and if the output of your power source is constant enough so there is no variation in the light output, the time you have to expose the negative and paper should be indendent of your size of paper and negative. There will be only two variables left: the density and contrast of your negative and the kind of paper you want to use. The denisity of your negative is set digitally by yourself, the curves and sensitivity of your paper is set by the manifacturer. A manufacturer like Ilford has excelent quality control and a given type of paper will have almost the same characteristics, independent of size and emulsion number.

There are a few devices to measure the output of your light source to match it to a certain paper. The Ilford thing mentioned earlier is one of these, the stopclock from RH design is another. Thing is that you have to calibrate these devices to the characteristics of the papers you want to use. This will costs you a few sheets of the given paper and about an hour or so work for each paper you want to use. This is about the same amount of effort it will cost you to figure out the exposure time for contact printing the classical way, using test strips.

So my idea would be to invest a few days of work to figure out if this works out for you, using a box of 8x10 paper of the quality of paper you are likely going to use. When it works out, you can upscale it without much effort. And when it doesn't: it was a good learning moment.

good and informative post. thanks..



I don't think you need to measure the light. If the print looks right on your computer, and you figure out one time the correct exposure to reproduce that on paper, then every time for every print you will get it right on the computer, print your digital negative, the give that your standard exposure. The density of the digital negative will be determined by your digital manipulations on the computer so the same exposure will give you the correct print every time. I think (but what do I know).

i think the same.. but what do i :)
my question relates to this part of your post: "and you figure out one time the correct exposure to reproduce that on paper"