Contact printing...misinformation?

[ic-racer]

Focus...

First off, thanks everyone for your replies, all suggestions are welcome.

Just to keep focused, here are the goals as a hierarchy:

Goals:
ANALOG
8x10
CONTACT PRINT USING AVAILABLE EQUIPMENT
VARIABLE CONTRAST PAPER

And again, the major problem:
WHITE SPECS SPOILING IMAGE

Solutions and consequences tested so far:
AVOID THE GLASS = no dust but poor sharpness (discussed later)
DIFFUSE THE LIGHT = no dust but poor sharpness

Things that DON"T work or are impossible:
DUSTING THE NEGATIVE UNDER SAFELIGHT. Won't work in my darkroom, it is too dark, you can't see the dust. The negative and glass have to be dusted under a high-intensity light for me to see the dust specs.

ASSUMING THE ENVIRONMENT IS DUST FREE. I already have a Honeywell ((there was a url link here which no longer exists). Its a great Idea to hook it to a timer to run it at night. I already have humidity control with dehumidifier, a humidifier (for different times of the year) and a sling phychrometer and a 'dial gauge' hygrometer to monitor humidity. Goals are 55 in the summer and 45 in the winter. (Without intervention the summer humidity is 65-70 and the winter humidity is 25-30)


Things yet to test:

1) PRINTING FRAME that allows one to 'pre-dust' the negative and mount it inside the frame and keep it there (nice an clean) while the back is subsequently removed and replaced repeatedly to make the test and final prints.

2) MORE PRESSURE on the glass/negative/paper unit, perhaps even vacuum or a well designed printing frame. This would allow the use of a diffuser between the enlarger and the negative.

3) OTHER LIGHT SOURCE MANIPULATIONS. Brunner's post gave me some ideas. I have a couple extra dichro. heads that could be turned into a dedicated VC light source...

The printing frame is going to be the most difficult to test because I don't have one yet I suspect that suggestions on this forum will be the most important factor in avoiding the problem of having to buy or make 2 or 3 frames to get a good one. So far Bostikc-Sullivan is tops on my list (but only from reading posts). Still about a day or two from being ready to buy one 'sight unseen' off the internet, again suggestions welcome.

Since this thread is remote from the original camera restoration thread, realize that, although I could afford any camera/lens I wanted, the goal of the 8x10 restoration was to get up and running at a cost that was consistent with the original price of the camera ($5.00 US). So it is like a challenge. Therefore, some 'controlled-light source-vaccum-printing' apparatus for $2000 is not in keeping with the spirit of the project (unless, of course I can build it myself .

 

[ic-racer]

More comments on the test results...

(http://www.largeformatphotography.info/forum/showpost.php?p=285139&postcount=90)

First and foremost I can see what I am after in the sharpest prints. They are indeed sharper than my best 4x5 negs enlarged to 8x10. Part of this whole project is a response in my part to a post (here or on LF forum) that an "8x10 contact would be superior to a 4x5 enlarged to 8x10". Always being skeptical, I wanted to see for myself, thus the incentive to get that 8x10 camera working after all these years.

Anyway, that sharp contact print really blew me away, it is really like holding a little miniature of the earth in my hand. It IS awesome and based on this, I am going to keep pushing forward with the project.

Another thing that I think was not clear is that I used the dirty scratched glass to AMPLIFY the problem I am trying to solve. For example, a few dust specs here and there are not going to show up well on a scan to post for your all to see. Also, the randomness of a few dust specs could influence the results. That is, I might get a better result because the few dust specs landed in inconspicuous places in the print, or by chance I got the glass cleaner for one test than another.

But along those lines, I was really surprised by the way the diffused light source makes all the problems go away! I am still amazed at this. It is an effect much more dramatic than I had expected. What a powerful tool (better than Photoshop because its an analog solution!)
Here is another link to the composite image:
http://img.photobucket.com/albums/v670/ic-racer/scratchcompare.jpg

 

[ic-racer]

Diffraction

I was serious when I posted I can only print at night, so I can't make any more tests right now, and there is no place I can drive today to get a contact frame (thought I may be able to cobble one together today when I get done wasting my time on the computer )

Anyway I did want to digress, and discuss the results obtained WITHOUT the glass. **CAUTION** this post may involve mathematics so pleas skip to the next post if not interested.

In the initial post I disregarded any effects of diffraction. I am not sure, but this may be an error. DIffraction is a sometimes mysterious process (one of my favorite real life examples I witnessed was being in a jet plane and seeing its 'shadow' cast as a 'bright spot' when we were at just the right distance for the diffraction pattern to show the center of the bulls-eye as light vs dark.)

Anyway, the test picture that was obtained WITHOUT the glass was not outside the bounds of the test equation. That is, the negative was NOT displaced more than 0.5 mm above the paper. Yet , this image is 'blurrier' than expected from the equation.

One possible explanation is diffraction. The pictures posted show a magnified area of the center of the image which is an image of BLADES OF GRASS that are on the other side of a small river, about 50 METERS FROM THE CAMERA.

Using the 'thin lens' formula with these numbers I can find the width of these blades of grass as they appear in the negative. Distance to grass = 50000mm, Distance to negative = 210mm, size of grass blade = 1mm, calculated size of grass blade image = 0.0042mm.


To refresh my memory, here is a simple quote from a basic web site on physics:

"The amount of bending depends on the relative size of the wavelength of light to the size of the opening. If the opening is much larger than the light's wavelength, the bending will be almost unnoticeable. However, if the two are closer in size or equal, the amount of bending is considerable..."

What I was underestimating is that light diffracts more when forced to go BETWEEN two objects rather than around one large object.

I had estimated that the light just has to go AROUND big opaque areas of silver, but, in-fact, the light is being forced to go BETWEEN the little images of the blades of grass. This is causing more diffraction than I had realized. Not sure but just a thought.

OK if you don't like math and optics you can start reading again at this point....

 

[Vaughn]

Newton rings can form between any two surfaces that are not in complete contact with each other. J

Just an observation...the rings can also form from uneven pressure. I packed a contact printing frame with extra padding to increase the pressure and only increased the rings. Areas directly under the springs were under greater pressure. Reducing the pressure by removing some of the extra packing got rid of the rings.

Vaughn

ic-racer -- I have a couple B&S contact printing frames...good quality!

 

[rwyoung]

Just a quick though, and you may have already dealt with this, but...

When I use my enlarger as my light source for contact printing, I leave the lens in so I can control the light via height and f/stop. But I also make sure to rack the focus (and now I can't remember if I'm racking it full in or out) so that the schmutz that might be on the condenser glass or on the filters won't be focused by the enlarger lens.

This probably isn't that important but if you were to leave a negative carrier with glass in the enlarger, you could potentially be focusing any of the dust on the carrier onto your final print. I stopped using glass carriers so my only concern is dust on the condenser lenses or VC filters.

 

[lee]

schmutz on a lens won't be in focus because the image is not in focus at that the lens point only at the contact of the paper and film. Clean working conditions from loading the film in the holder to drying the film and then contact printing the neg need to be worked out. I generally wash the glass on both sides with soap and water and then dry it. I use a pretty heavy piece of glass I got somewhere several years ago and I use a piece of foam rubber under the paper film and glass.

Making quality 8x10 contacts is not hard to do but you will have several process problems to work out. Dust is just one of them.

here is a sample of some of my contact prints http://photographs-johng.com/ROG2/index_2.htm mine are on the top row. click on the image to enlarge. These are for a cancer charity.

lee\c

 

[ic-racer]

. I use a pretty heavy piece of glass I got somewhere several years ago and I use a piece of foam rubber under the paper film and glass.

I was re-reading "The Print" today and Ansel's description of contact printing is brief. In fact I suspect there are many on this forum that could write a much better chapter. He has a picture of a similar setup in the book (ie thick glass over foam rubber). A big obstacle for me is the thought of the negative touching the rubber when doing little test strips. I use strips and Ansel seems to indicate he uses whole sheets which is probably the safest thing to do (in terms of getting anything on the negative). I know there are many types of foam rubber from browsing the McMaster Carr catalogue and I suspect some of them can leave a residue (on the negative, when doing skinny test strips that is...I'm not overly concerned about the back of the paper touching the rubber).

Ansel also indicates that he dusts the negative then places it with the paper under the glass. I just don't see how this is possible. I need a high intensity white light shining on the negative to see the dust. He doesn't explain.

Also, what do you do once the you take the paper out? Do you pull the paper out and let the negative touch the foam? Do you have something over the foam? If so what is it and how do you clean it? Or do you put the negative back in it's plastic sleeve or wherever inbetween exposures?
How or where do you store the glass? Do you wear the white gloves when assembling the sandwich under the safelight?

I think these details are important. I mean, this isn't some 6th grade photography course, these prints will represent the culmination of my 30 years of darkroom work.

Someone mentioned Newton's rings and I think most of the good solutions have been covered on prior posts, but I'm shure I will be there at some point. Personally, I cannot imagine projection printing without 'anti-Newton ring' glass on the flim base side. I guess this brings one hesitation toward the $125 B&S frame. Which is the possible need to replace the glass in it with some anti newton or anti-glare glass. And then there is the concern that the texture in that glass will show up with direct enlarger light (I'm sure someone out there has checked this)

It would be nice to have a good write up on contact printing for the expert that covers all the little details. For example I know that when I projection print there are a hundred little details extending through negative deveopment time, format, framing, borders, neg-carrier issues, lightbox issues, lens focal length, lens aperture, alignment, column steadyness, foot pedal vs button, counter steadyness, bla bla bla.

 

[David A. Goldfarb]

Ansel's description is brief, because it's not a complicated process, and doesn't require much more than a general knowledge of the principles of photography and a little common sense.

If you want to contact print onto a strip and don't want the neg to touch the foam (if you are using foam--I use a split-back print frame), then put a sheet of paper (any kind of paper) under the photographic paper for the purpose of the test strip.

I do wear white cotton gloves when setting up a contact print, since the neg, paper, and glass can all get fingerprints. Between exposures I just lay the top of the frame face down with the neg emulsion side up, and the back next to it. Re-sleeving between exposures would be excessive handling.

Test with your film before investing in A-N glass. Some sheet films have a retouching surface on the base, which is less likely to contribute to Newton's rings.

Newton's rings are an interference pattern caused by light reflecting between the film and the glass. Some A-N glass is textured, but some has an anti-reflective coating rather than a texture, which is more expensive. Yes, you can obtain A-N glass for any contact printing frame. There are various sources.

 

[Mateo]

Oh man, please forgive me in advance if I'm wrong but kinda I think someone is pulling everybody's leg here. I ain't got no 30 years of darkroom work to culminate about but I did figure out how to dust a negative. I think we're all getting laughed at here.

Uh oh, I just thought...did you dust your negative holders all them years?

 

[lee]

Mateo may be right about this.

I have never worried about the neg touching the foam. I have never seen a problem with it. I dont wear white gloves either. I do wash my hands a lot.

Am I correct in assuming that in your 30 years of darkroom work you have never made a contact print?

lee\c

 

[removed account4]

i never knew making a contact print / contact sheet
could be so difficult or confusing that it would take 4 pages
to explain:

i thought it was just:

negative under glass, on top of paper
.. turn light on - any light
.. expose paper

maybe i am missing something ?

john

 

[Harrigan]

If dust is the problem learn how to spot your prints properly. I have never produced a contact silver gelatin print that did not require some spotting. This is a basic and necessary part of the hand made printing process.

I would also recommend against the cotton gloves as these have quite a bit of lint and collect dust particles that can drop onto your glass. If you use them make sure when you’re done to keep them sealed up and not simply laying around. I simply use a 10x12 sheet of glass for 8x10 contacts and don’t worry about fingerprints on the outer edges as this area is never used. I replace my glass if it has defects on it. I always make sure to clean the oils off my hands before handling negatives.

Keep your work area clean. I work in an old dusty house built in 1940. My darkroom is kept as clean as possible but there is no way I can keep all the dust off a contact print. Dust is part of printing, learn to deal with it.

 

[rwyoung]

schmutz on a lens won't be in focus because the image is not in focus at that the lens point only at the contact of the paper and film.

lee\c

Not on the LENS, on the negative carrier (if it had glass and was left in place) or on the bottom side of the condenser glass. And possibly on the contrast filter, depending on where you put it. I could put it above or below the condenser glass and I choose above to make sure it is too far away to matter.

 

[ic-racer]

Uh oh, I just thought...did you dust your negative holders all them years?

Sorry, but this post is split, with the 'camera' part over in the LF website. The holders are only a few days old and are very clean. They have only gone through one round of films since I got them and I have not had a problem with dust. (http://www.largeformatphotography.info/forum/showpost.php?p=283867&postcount=88)

Maybe I am missing something here but to use a piece of glass (rather than a frame) would require dusting the negative under safelight conditions right?

 

[ic-racer]

.. turn light on - any light .......
maybe i am missing something ?

Yes, light color influeces contranst of VC materials.

 

[removed account4]

Yes, light color influeces contranst of VC materials.

cool, i appreciate you helping me out here.
i am kind of oblivious to this sort of thing ...

john

 

[ic-racer]

Mateo may be right about this.

I have never worried about the neg touching the foam. I have never seen a problem with it. I dont wear white gloves either. I do wash my hands a lot.

Am I correct in assuming that in your 30 years of darkroom work you have never made a contact print?

lee\c

I recall making some 4x5 contacts in graduate school, but other than that, never an 8x10. I used to make what one would call 'proof prints' of pages of roll-film negatives back in the 70s and early 80s but stopped. I can safely say that up till a few days ago I was 100% projection printing.

I think based on some of these suggestions I am going to try some 'framing' glass that I have and see how that works. I could weight it at the edges to simulate thicker glass. If that works then I could have a glass co. cut and edge-polish a nice thick piece of glass for me. The issue of dusting the negative under the safelight still is somewhat of a dilema, I wonder if those little portable safelights that you can wear around your neck are bright enough to show the dust when held close to the negative?

Maybe I'll pick up a Spotone kit, but I hope using it won't be my standard routine.

 

[ic-racer]

I think we're all getting laughed at here.

Oh yea, I spent two months working almost non-stop on a project (documented here: http://www.largeformatphotography.info/forum/showthread.php?t=29267) just to have a few laughs with you all....:rolleyes:


Seriously, though, If you dust your negatives under white light or safelight, let me know. If you do it under white light, what do you do with the clean negative while you are preparing the paper and glass under safelight conditions? I think at this point this is this issue that will sway me between the simple glass plate vs the contact frame. I was kind of set on the contact frame until I re-read Adams, where he says he does not use it.

Adams admits he did not do many contact prints at the time he wrote that chapter, so maybe he is not so much an expert on that topic. Also, his negatives are not currently contact printed:

"The prints are made by projection rather than by contact, regardless of negative format. This ensures a consistency in finished size and also affords the greatest control of dodging and burning. Most of the negatives in the series are 8x10 format, but other negative sizes include 5x7, 4x5, 31/4x41/4, and 120 rollfilm. The 8x10 and 5x7 negatives are printed in the Beseler 8x10 enlarger designed by Ross, with a custom Aristo 12"x12" cold-light head. Negatives 4x5 and smaller are printed with an Omega D5500 enlarger with a diffusion color-head" from http://www.anseladams.com/content/care_collecting/SEP_processing_methods.html

 

[lee]

ic racer typed this, "Oh yea, I spent two months working almost non-stop on a project (documented here: Dead Link Removed) just to have a few laughs with you all...."

something just set off the alarm bells...

Question 1. is this a new bellows?

Question 2. if not, have you vacuumed it out lately? if not, do so.

Question 3. how high is the relative humidity in your darkroom? if low I would add water someway to raise the humidity. That will cause the dust to start to lay down.

Question 4. since you share a space with a wood working area I would re-double my efforts to clean the area again.

I would also recommend that you get a non static cloth or brush to wipe the glass BEFORE you let it make contact with your neg and paper.

lee\c

 

[dslater]

ASSUMING THE ENVIRONMENT IS DUST FREE. I already have a Honeywell ((there was a url link here which no longer exists). Its a great Idea to hook it to a timer to run it at night. I already have humidity control with dehumidifier, a humidifier (for different times of the year) and a sling phychrometer and a 'dial gauge' hygrometer to monitor humidity. Goals are 55 in the summer and 45 in the winter. (Without intervention the summer humidity is 65-70 and the winter humidity is 25-30)

I had a look at this link. I don't see how you can have a dust-free environment when you're sharing your dark room with a work shop and storage. If I were you, I'd try to find some way to close off a dedicated darkroom area and make that as dust free as possible.

Dan

 

[David A. Goldfarb]

Seriously, though, If you dust your negatives under white light or safelight, let me know. If you do it under white light, what do you do with the clean negative while you are preparing the paper and glass under safelight conditions? I think at this point this is this issue that will sway me between the simple glass plate vs the contact frame. I was kind of set on the contact frame until I re-read Adams, where he says he does not use it.

I use a contact print frame, and I dust the glass and the neg with a 4" Kinetronics brush and/or Dust Off with the lights on. Frame goes face down, neg face up on the glass, lights off. If I notice any dust under safelight, then I'll dust it off again.

 

[ic-racer]

Who really WANTS to do contacts?

After reading that web site on printing Adams work I was curious how you all felt about contact printing 8x10 vs Projection printing. That is, do you contact print because you don't have an 8x10 enlarger? Or do you do it because it is "better" than using an enlarger?

Personally, I'd like to get an 8x10 enlarger at some point, if I decide to stick with the 8x10. I guess that if I were to convince myself that contacts were better, it would temper my enthusiasm for an 8x10 enlarger.

 

[Ian Leake]

Who really WANTS to do contacts?

I do, for one. OK, I use Pt/Pd but even when I was printing on enlarger paper I prefered contact prints. For me they are the right size, richer, "truer" (for want of a better word), and easier than enlarging. All of that is subjective (and other people will surely have a different opinion), but for me contact prints are the only way to go. I still have an enlarger, but only because I'd like to work out how to create internegatives from 6x6 roll film.

 

[David A. Goldfarb]

They're different. Big prints from big negs can be impressive, but contact prints can have a kind of three-dimensional quality that is characteristic of contact prints.

There is also something appealing about working at a 1:1 ratio, where the image you see on the groundglass is the same size as the print.

Contact printing of course opens up the possibility of other processes, and that has its attractions.

 

[PhotoHistorian]

After reading that web site on printing Adams work I was curious how you all felt about contact printing 8x10 vs Projection printing. That is, do you contact print because you don't have an 8x10 enlarger? Or do you do it because it is "better" than using an enlarger?

Personally, I'd like to get an 8x10 enlarger at some point, if I decide to stick with the 8x10. I guess that if I were to convince myself that contacts were better, it would temper my enthusiasm for an 8x10 enlarger.

PLEASE don't buy an 8x10 enlarger. APUG doesn't have enough file space on their servers to help you accomplish using one. If you can't contact print GIVE UP! My wife and I have taught kindergarteners how to contact print and with excellent results. I can't believe this discussion has gone on for 5 pages!

Walker