Problems with Foma and Ilford FB papers

fdelconte10

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Hi Everybody,

I am having a hard time understanding something happening in the darkroom. I have to print, for an upcoming exhibition, some 50x60 cm photographs, views of the starry sky on 6x7 film. I've made them using an equatorial mount, 40 minutes exposure for each shot. I really like Foma FB glossy paper and I've started using it. The prints come out really well but there is a strange thing happening. Small haloes and stains appear. They are not extremely visible in real life but they bother me a lot. I attached a couple of example. On these sky views they might be more visible then on other types of pictures, let's say landscapes. My working flow is really clean: new chemicals every time, new latex gloves for every final print. I use five liters of chemistry in each tray. I am pretty sure it is a problem of the paper. Has someone experienced something similar?

After some disappointing darkroom sessions, I've decided then to change paper. I am now using Ilford FB paper and I'am having another problem. The photographs are way less contrasty then the previous one made with Foma. The settings of the enlarger are the same ( magenta filter at its maximum) as it is the the developing process. The last time I've used Ilford paper has been many years ago so I am not familiar with it. I wonder, is it a less contrasty paper then Foma? The difference is huge. To show the same amount of stars with the Ilford paper, I need a surprisingly shorter exposure, thus making the sky light gray and not dark. So it is really not an option. If I achieve the proper shade of gray for the sky, I lose so many stars. Does someone has an insight about it? Final consideration, with the Ilford paper I don't have the haloes.

I really need some help friends, it is so frustrating.

Thanks a lot and greetings from Brussels,
Francesco
 

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koraks

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Nice to hear from you again Francesco! It's been a while since we were in touch via email.

fdelconte10 said:
is it a less contrasty paper then Foma?
Click to expand...

No. I suspect you're not developing the Ilford paper to completion. What developer do you use, at what dilution, at what temperature and how long is your development time?

I suspect the problem with the weird stains on the Foma paper is due to the same cause: insufficient development. As a result, you're seeing the remnants of the uneven wetting of the paper when it just hits the developer.
PS: on second thought, maybe the stains are just drying marks on your negatives, but they're not showing up on the Ilford prints because they lack contrast. They may appear on the Ilford paper just the same once you start developing that to completion.
 
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fdelconte10

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Thanks a lot for the fast reply. I normally use Ilford Multigrade 1+9 at around 20°. Just measured the temperature and now is 19°. Developing time is 3 minutes. A few days ago I tried to develop the Ilford paper with the 1+14 dilution for 4 and 5 minutes. I had the same problem, The amount of stars is really really smaller if compared to the Foma paper. I even wonder if something might has happened with the magenta filter of my enlarger, a Durst 138 with the CLS 1000 color head.

Do you have suggestions to solve the problems?
 
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fdelconte10

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The negatives are fine, the stains change position every time. I don't understand how not developing to completion might create (on the Ilford paper) photos with less stars but with the desired shade of dark gray/black of the sky.

And yes, nice talking to you again! =D
 

Don_ih

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It does look like uneven development. Are you constantly agitating the print to keep fresh developer moving over it for the duration? Otherwise, maybe your developer is worn out?
 

koraks

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fdelconte10 said:
The negatives are fine, the stains change position every time.
Click to expand...

That's an important clue. This means they're specific to the print. As @Don_ih also says, it looks like uneven development. Assuming you're agitating sufficiently, worn out developer can indeed be a cause of this issue. Contamination of the tray with fixer is also a possibility if you're working with a single tray, and doing the drain & fill routine (fill tray with developer, develop print, drain developer into a jug, add stop bath to the tray with the print still in it, drain, add fixer to the tray, etc.)

fdelconte10 said:
I don't understand how not developing to completion might create (on the Ilford paper) photos with less stars but with the desired shade of dark gray/black of the sky.
Click to expand...

Sorry, I misunderstood; when you said 'less contrast' for the Ilford paper, I assumed you meant that the black you got was not as deep as with the Foma. If you're 'losing stars' in the sense that the weaker/less bright ones disappear, you're evidently overexposing the print. Make some new test strips.
Given that you're working with full magenta filtration, it also seems that your negatives are a little on the thin side. That makes it a bit of an uphill battle.

In cases like these it always helps if you provide clear examples of all the problems/symptoms. Here, it would help to be able to see a comparison between the Foma and Ilford prints you've produced so it's easier to tell what you mean by the difference in contrast.
 
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fdelconte10

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Thanks guys for the support. I work with several trays and not just one. I make new developer for every session. Since I've started to make this astro-prints, the higher number of 50x60 cm prints I made in one session was 5. I work with 5 liters. So, way less then what recommended on the Ilford instructions right?

By their nature, the negatives are indeed really transparent and they request the highest contrast. The thing is that I am really satisfied with the contrast and the look I achieve with the Foma paper. If it weren't for the haloes the prints would be perfect. I start the developing with the print face down and after 30 seconds I turn it face up. From there I agitate the tray. I've now tried a shorter exposure and a longer development ( 5 minutes). It is a little better but still light years away from the Foma paper.

Last year I've been printing the same negatives on Foma. Same workflow. I remember having some similar issues but less visible.

I attach a comparison between Ilford and Foma paper (there are many reflexes because the paper is glossy)
 

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koraks

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fdelconte10 said:
So, way less then what recommended on the Ilford instructions right?
Click to expand...

Yes, that should be well within the capacity of the developer.
When did you open this bottle of developer concentrate and what color is it? I.e. is there any chance that the concentrate has gone bad since the bottle was bought?

fdelconte10 said:
I've now tried a shorter exposure and I longer development ( 5 minutes).
Click to expand...

What you need to do is take a strip of the Ilford paper and make a test strip to determine the shortest exposure time to get maximum black through your negative. Then use that time. For the 1+14 dilution of Ilford Multigrade I would stick to 5 minutes development time in any case, since you need all the contrast you can get. I think you're still overexposing your Ilford prints and the loss of starts is the result of this.

Note that the grade 5 on Fomabrom is actually a lower contrast than grade 5 on Ilford Multigrade FB Classic. Compare the curves in the datasheet and do a test strip using a step wedge; you'll see. So if you get a lower contrast from the Ilford paper, it really suggests a processing/handling problem.
Be sure to also exclude any chances of fogging on your paper - although Fomabrom is much more sensitive to this than Ilford due to the difference in spectral sensitivity.
 

ic-racer

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Face down promotes air pockets.

If you need more contrast try dilute lith developer. Also, next time increase negative development.
 

Don_ih

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If you have access to some lith film, you can try copying the negatives. If you make a contact print on lith film and reverse develop it, you can either use that to make your prints or stack it with the existing negative to add density to your stars.
 

pentaxuser

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If the OP does not have the haloes with Ilford paper and does everything else the same way then doesn't this suggest that the haloes might be specific to the Foma as everything else appears to be the same in terms of his method ?

If he uses max magenta with both types of paper, as he says he does, but gets much lower contrast with Ilford paper then even if Foma is inherently more contrasty i.e. say 1/2 to one grade more contrasty than Ilford at the same grade setting then the way the difference in contrast is expressed by him suggests that any difference in inherent contrast is way more than just a half or even one grade

Francesco, I take it that both shots you have shown us are on Foma paper as both have haloes. If that is the case can you show us the Ilford paper prints so we can see the difference?

Thanks

pentaxuser
 

koraks

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pentaxuser said:
doesn't this suggest that the haloes might be specific to the Foma as everything else appears to be the same in terms of his method ?
Click to expand...

Sure, but a problem can be specific to a combination of factors. In this case, it's very well possible that the risk of air bubbles suggested by @mshchem creates this particular problem with Fomabrom when developed in this dilution of this particular developer, etc. Change one or two factors and the problem 'magically' goes away.

pentaxuser said:
even if Foma is inherently more contrasty
Click to expand...

It isn't. It's the other way around.

pentaxuser said:
any difference in inherent contrast
Click to expand...

I don't know what 'inherent contrast' means in this context.
The difference in contrast seems to me to be caused mostly by overexposure of the Ilford print. Exposure is critical if you want to preserve the faintest of stars on a negative that's already very low in contrast to begin with. You really need to make incremental test strips with very small differences in exposure between the steps to exactly nail the sweet spot between getting sufficient density in the black background while not loosing too many of the weaker stars.

pentaxuser said:
I take it that both shots you have shown us are on Foma paper as both have haloes.
Click to expand...

The images in post #1 are both on Foma paper. Post #9 shows Foma paper on the left and Ilford paper on the right. The problem with the 'halos' (which I think is not really an appropriate term for these low density defects) is not very apparent in the full-sheet photo in post #9. It shows up more clearly on the close-up in post #1.
 

pentaxuser

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Thanks koraks I can only hope for the OP's sake that you are right on all counts above. I must admit I had assumed that when changing paper from Foma to Ilford he had done the standard test print again doing what you had suggested and not simply hoped that the same enlarger exposure was right for either paper

Based on what you said I note that he has shortened exposure and it was better but still not what he wants

Francesco have you tried a range of exposures in say a series of quarter stops either side of what you found to now be the better exposure? You could of course simply start with what you have found to be the better exposure and decrease in say quarter or smaller fractions of stops but I mention a range either side of the better exposure you have already achieved just to be sure that you can rule out longer exposures being of any value

pentaxuser
 
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fdelconte10

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Hi guys,

It was a long day but eventually I made it. I tried again with the Foma paper, mainly because I love its glossy finish, and I solved the issue. It was most likely, as suggested, an underdevelopment problem. I processed the print face up and extended the developing time from 3 to 5 minutes. The halos /stains did not appear this time. I am so relived.

Don't know whats going on with the Ilford paper. I probably can't work it well.
@koraks you are probably right when you say that the point is finding exactly the sweet spot between getting sufficient density in the black background while not loosing too many of the weaker stars. However, with the Foma paper is really not a difficult thing to do.


It is exactly as explained by @koraks

I attached one of the two prints I eventually made today: the star Deneb in the constellation of Cygnus.

Thank you all for the help,
Best
Francesco
 

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RalphLambrecht

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May be it was backgroundradiation from the big bang? Just kidding. Glad you figured it out.
 

Sal Santamaura

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fdelconte10 said:
...I tried again with the Foma paper, mainly because I love its glossy finish...
Click to expand...

While not perfect, the surface shine of air-dried glossy Foma 111 is the least bad available today. Unlike Ilford's glossy fiber papers, which cause unacceptable distracting reflections unless displayed under carefully controlled lighting. As a bonus, Foma's product is flatter out of the box and stays that way after drying on screens.
 

koraks

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fdelconte10 said:
I attached one of the two prints I eventually made today: the star Deneb in the constellation of Cygnus.
Click to expand...

It's magnificent! I'm so glad to hear you've been able to solve the problem.
The Foma paper is a fine paper; I've always used it with pleasure.

fdelconte10 said:
finding exactly the sweet spot between getting sufficient density in the black background while not loosing too many of the weaker stars. However, with the Foma paper is really not a difficult thing to do.
Click to expand...
It's easier with the Foma paper because the curve is less steep. This makes the sweet spot a little wider (but the contrast lower, evidently). I think that may have been part of the reason why you had trouble finding the sweet spot with the Ilford paper. For a print like yours, a tiny difference in exposure makes a big difference. This is a little less so with the Foma paper, which gives you some more leeway.
 
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fdelconte10

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Really thanks again. I will send you an email with the details of the exhibition. It opens at the end of January in Brussels during the Photo Festival. I am also showing a piece related to my research about colors. You might come and have a look =)
 

grain elevator

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Glad you were able to solve it! Just in case, if you need to increase contest further, beside Lith printing which has been mentioned, there is also the possibility of using a blue filter, and lastly, using farmer's reducer to lighten a print that was printed darker than the outcome is intended (works more on the highlights than in the shadows, thus increases contrast).
 
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fdelconte10

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Thanks! And thanks for the information. I don't have time for experimenting now but I will keep that in mind
 
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