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rcmartins
9-Aug-2014, 15:39
Recently I took several photos of an indoors old hydraulic power plant with fuji NS160 sheets. I'm not used to this film, being more used to portra 160. The exposure as metered should have been 5 s but not having at hand any information I shot as if it was portra which in my typical development would imply 2 stops of compensation so I opened the shutter for 20 s. When I managed to get a hold of the fuji datasheet I got worried since it says that it requires a simple 1/3 stop extra development. Basically I overexposed 1+2/3 stops. I know that typically C41 film can withstand great amounts of overexposure but I would like to optically print to RA4 paper and am not sure if I can do it with that much overexposure. Can I correct, to some extent, this dumb error during development? Thank you very much for any input.
raul

Liquid Artist
9-Aug-2014, 16:36
The chances are that it won't be all that bad and you can pull it in the printing process.
However there are some labs that can pull or push a stop or 2, but you will have to do some research to see who can in you country. If there is no one else who can, I believe that Dwayne's in the USA can.

The third option is you can always buy the chemistry, and develop it yourself.

rcmartins
9-Aug-2014, 16:53
Thank you for your reply. Yes, you are right, I forgot to add. I am used to doing my own development with the tetenal 5 liter kit and a Jobo CPA2. The tetenal uses a color developer followed by the blix, rinse and stabilizer. I am guessing that to pull I have to shorten just the first color development bath. However, I don't know by how much nor if it is better to change the temperature instead or both (time shortened and temperatures lowered). I am guessing that temperature is not something to temper with in C41 but am not knowledgeable enough about this process to be sure and color negatives, specially in sheet sizes, are kind of expensive to play with. Also, I am guessing that at some point, negative or print, I will pay a price in color shift. This can be a bit troublesome since I mixed daylight (shadow) with flash. I used the flash to paint with light some of the most gruesome details in the machinery. The color shift might unbalance the white balance, I guess. Some directions would be very much welcomed.
raul

Liquid Artist
9-Aug-2014, 21:05
I just googled up tetenal push pull processing, and it looks like there should be an instruction sheet inside.
It also sounds like it is around +or- 30 seconds per stop.

With old flashbulbs and film you may have an issue with color shifting, but it doesn't seem to be that big of a deal these days. So I think you may be lucky there, and could have some interesting results.
If not, and I hate to say this word but Photoshop may become your best friend.

One thing I love about sheet film is that you aren't destroying all your photos at once if you have some difficult processing to do. Try 1 sheet first, and go from there. If possible use a sheet you may have duplicated with bracketing or something.

Good luck, and please post the results here if they turn out.
It could interest others who may have the same issue.

Daniel Stone
9-Aug-2014, 21:52
I've unintentionally overexposed 160S sheet film before, rated it at 50. It came out fine with NORMAL processing. A bit light on global contrast compared with a normally-shot negative, but was easily corrected in post(scanning)

With C-41(and it's 3:15 development time), PULL processing can incite color shifts past a 1/2 stop that I've found in my preliminary testing. I wouldn't recommend that you pull your film unless you have tested the same film + development scenario before committing critical shots to "on a whim" development.

If it were me, I'd just have the film processed normally(so no pulls), and then when scanning, you'll be able to adjust your exposure using curves.

Just my 2

-Dan

Henry Ambrose
10-Aug-2014, 06:21
It will almost certainly be fine with normal processing. Of all the color films you could have picked, this one is the most accommodating of over exposure. In the past I've shot boxes and boxes of this film rated at 100 with excellent results. Your exposure is not far off and definitely better than not enough exposure.

LF_rookie_to_be
10-Aug-2014, 06:38
Pulling 30 or even 45 seconds can help a lot if you intend to print the negatives in the darkroom onto current RA4 papers, which are almost all extremely contrasty and saturated. But since you already overexposed, the contrast and saturation are reduced. Should be fine with normal development and print well. Which paper are you using?

Bruce Watson
10-Aug-2014, 06:57
With C-41(and it's 3:15 development time), PULL processing can incite color shifts past a 1/2 stop that I've found in my preliminary testing.

This. The C41 process is not designed for variable development times. The time/temperature was designed to allow the chemistry to diffuse properly through all the many layers in the emulsion. This, takes time. If you reduce the time in developer, you severely reduce the time the developer has with the inner-most layers of the emulsion. Which will almost certainly induce (non-linear) color shifts. Which are difficult to impossible to correct with darkroom printing.

Best bet, process normally. OTOH, if you insist on shortening the development time and cause color shifts in the negative, you can always drum scan it, correct the color shifts in an image editor, and send the resulting file to something like a lightjet printer, so you still end up with a darkroom print. Or inkjet print a new negative at final print size and make a contact print from that. There are many paths to the waterfall.

rcmartins
10-Aug-2014, 18:04
Thank you all for the replies and help. The consensus seems to be to develop the film as if it was correctly exposed. Ok, I'll do just that. I'll start with just a few sheets to see how they come out though it seems that there isn't much I can do about it. I do not want to go the digital path - not that I have anything against the digital, but it simply isn't the path I enjoy taking and I much prefer the look and mood I get with the optical printing. This is part of the problem since I am still learning to control the optical RA4 process and still struggling with changing the contrast...something pretty trivial with B&W but that has been eluding me in the RA4 process. Overexposing a negative typically implies lower contrast, though I'm not sure with this film, and not being proficient at changing contrast and wanting it for aesthetic reasons is what set me trying to look for solutions.
These photos are being taken at the Azores Islands. I will be here one more week and will try to get authorization for another set of pictures which hopefully will allow me to ensure proper exposure - I also managed to get more fresh film which a friend sent me by mail.
In the next weekend I will get home and develop the first set of sheets. I will also make some contact proofs so that I can get a grasp of how they will behave in terms of contrast, grain and color shifts. I will post the results here.
Again, my sincere thank you for the help.
raul

rcmartins
10-Aug-2014, 18:14
I forgot to add that I will be printing in the fuji crystal archive paper, the one that is most easily found in precut sheets. I have, however, placed an order at Calumet UK for the fujifilm flex crystal archive supergloss paper. They haven't shown any reaction to my order in a week so I am not sure if I will be able to pursue that route or not. The aesthetics I am looking for for this project would call for such a saturated and contrasty paper but in europe it is very hard to get.
raul

rcmartins
5-Sep-2014, 01:24
Just to bring a follow up. I have developed all the film and made some prints. As pretty much everyone stated, the two stop overexposure was extremely well handled by the Fuji NS160. I developed as usual with the tetenal 5L kit and used the 1-4 film dev. time: 3m15s.If anything, there was a slight blue tint on the negs, at least when printing on RA-4 paper (optical), but a very, very light tint that probably can be attributed to something else, like mixing shadow with flash (in some others, like the one I am placing here as an example, I also had to mix fluorescent bulb lighting). I did not notice any particular increase in grain.
In several of these photos, and the one I am putting here as an example I did it too, I made the shot firing several times the shutter thus integrating the light from the several exposures. I did it to accommodate the recharging time for the batteries of the flash unit I was using. If I hadn't done this I wouldn't be able to use as much flash. In terms of light it came out as I wanted it but what I notice is that the negative is blurred. It's not noticeable here, as the resolution is too low, but if I enlarge it 15x or more, it shows. As much as I tried to not move the camera, the force needed to cock the shutter must have also moved slightly the camera. The photo that I show here had the shutter fired 6 times. I will have to find a way to fix better my camera to the tripod head, or better fix the front panel.
The sheets went through the airport hand luggage security check x-ray machine twice. No harm as far as I can tell.
Thank you everybody for your help.
raul
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vinny
5-Sep-2014, 03:30
Over exposure decreases apparent grain.

Drew Wiley
5-Sep-2014, 08:26
I certainly wouldn't mess with the development, for reasons already stated. The neg might come out a bit dense, or maybe just fine. Hard to say exactly how well it will print without trying. A lot depends on the original scene contrast. The only darkroom way to fine-tune contrast on Fujiflex is via some kind of registered silver
mask to the neg. But most of the time that isn't necessary. Hard to say in this case. Depending on the subject, you might be able to simply dodge and burn your
way through any problems. I wouldn't worry too much at this point. That particular film has a fair amount of wiggle room.

Drew Wiley
5-Sep-2014, 08:28
Oh, sorry... I just noticed you already posted. Looks like you succeeded to some extent, though fluorescent lighting is always something of an issue.

rcmartins
6-Sep-2014, 08:54
Drew, no problem and I appreciate all the help. The density of the negs did not accompany the overexposure. In particular, while the overexposure was 2 stops, while enlarging the exposure was just 1 stop over what would be required for an equivalent neg. This is obviously a rough approximation since it depends on the overall lighting range of each negative, but I am confident that I am not far off with this estimate.
To control the contrast I am using a CRM (Contrast Reduction Mask) in a registered carrier. For these negatives the highest density of the mask is around 0.15. I then also use a SCIM (Shadow Control Increase Mask) to make the print more punchier.
As for fluorescent, indeed it is an issue, and quite a lot of paper is wasted while trying to find an equilibrium point that suits my taste. Its fun but it isn't cheap.
raul