B&W has more grain with Polariser filter?

[Robin Guymer]

On a recent trip to Freycinet Nat Park in Tasmania, I shot quite a few scenes over ocean and lake water. Some with a Polariser filter and some without. The shots with the filter on seem to have created more grain particularly evident in the skyline. Is this a typical result using a Polariser?

Using a tripod for some lake water shots, with the Nikon FA set on P, the shots came out fine. But I tried to flatten the water with long exposures using setting A at F16 which was reading 1/8th. These just developed clear on the neg which I guess is overexposed. So is a Polariser filter not suitable for this and should I have used a red filter or a ND filter instead?

Using Nikon FA, Nikkor 35-135, Pancro 400, Caffenol C-L

 

[markbarendt]

Film grain is unaffected by filters.

What is affected is the light that reaches the film, so the localized contrast and the placement of tones for specific subject matter will be different.

These changes can make grain look more prominent but it is really only a difference in the exposure of the film.

 

[pentaxuser]

Is the increased graininess apparent in the darkroom print or are you scanning the neg and reversing it for viewing and /or printing?

In other words might it be a scanning issue? Just a thought

pentaxuser

 

[Prof_Pixel]

But I tried to flatten the water with long exposures using setting A at F16 which was reading 1/8th. These just developed clear on the neg which I guess is overexposed.

Clear film on the B&W negative means underexposure and NOT overexposure

 

[Robin Guymer]

Is the increased graininess apparent in the darkroom print or are you scanning the neg and reversing it for viewing and /or printing?

The negs have been scanned for viewing. I think the previous post from Mark is correct in that it is my poor exposure of the shot rather than the Polariser filter. These shots show the different results I got. The 1st photo is without the filter.

 

[markbarendt]

I think the previous post from Mark is correct in that it is my poor exposure

That was definitely not my point.

My point is purely that the grain is inherent in the film chosen. The fix for too much grain is not normally an adjustment to exposure, the fix is typically a different, less grainy, film choice. A 100 speed film instead of 400, T-Max 400 instead of Panchro 400, C41 instead of traditional B&W...

 

[Thomas Bertilsson]

The second picture above is showing lots of scanner artifacts too.

I second @markbarendt and his comment above, that grain is largely inherent to the film, and while choice of film developer will affect that outcome to some extent, there isn't much one can do to get around the level of grain a certain film will produce.

With that said, underexposure will typically result in thin negatives, where the scanner will accentuate the grain because it is trying to normalize the tones that are in your negative. If you print an underexposed negative in the darkroom, you will not see that same increase in graininess.
Over-exposure will produce more grain too, but that is a result of silver density being higher in a denser negative, meaning it takes more silver to make up the image. Since there is more silver there are more silver grains, and when you scan or print such a negative the increased grain will be immediately noticeable.

So, particularly when negatives are scanned, exposure and development will be important to how much grain will be apparent in the files. When adding a polarizing filter, exposure requirements change, and the light that reaches the film surface will be different, meaning you will have to learn how to expose properly through it in varying lighting conditions for your grain to look as normal.

 

[markbarendt]

I don't disagree Thomas.

Part of my thought though is that typically people get very reasonable exposure values for most shots, truly poor exposures are rare in my opinion. Poor exposures are also typically quite obvious, I don't see evidence of that in the examples here.

The difference I see in these examples is that the shot with the polarizer has detail in the sky. Personally, I'd happily put up with the more prominent grain in exchange for the more interesting sky.

 

[MattKing]

Use of a polarizer can have a marked effect on localized contrast and the appearance of detail edges. Localized contrast and detail edges seem to sometimes have a marked effect on how scanners and scanning software interpret the negative.
Try scanning with the negatives in the other direction, to see if there is an observable change in appearance. If so, that would be a clue indicating that it is the scanning software that is accentuating the grain.

 

[Old-N-Feeble]

The grain in the non-textural mid tones looks about the same to me.

 

[Sirius Glass]

Grain is in the film and developer. Filters will not by themselves change the grain.

 

[samcomet]

Robin,
For what this comment is worth - I have been shooting film my whole life (50 years +) but ony recently been scanning the negs to keep an inventory so to speak. My scanned negs look like yours with big grain but when I print in my wet darkroom - no issues. Grain reduced significantly. I cannot say for sure that it is what you may find but it may be worth a go for your own peace of mind and print your negs in a wet silver environment.
Cheers,
Sam

 

[darinwc]

When scanning underexposed negatives, the software must increase the amplification digitally. The scanner lamp does not get any brighter. This also increases the apparent grain. Either from the existing grain or from dust in the optical system or digital noise.

You may find them more printable with a traditional darkroom.

 

[Robin Guymer]

Robin,
For what this comment is worth - I have been shooting film my whole life (50 years +) but ony recently been scanning the negs to keep an inventory so to speak. My scanned negs look like yours with big grain but when I print in my wet darkroom - no issues. Grain reduced significantly. I cannot say for sure that it is what you may find but it may be worth a go for your own peace of mind and print your negs in a wet silver environment.
Cheers,
Sam

Thank you Sam ( and thanks Darin and everyone else taking the time to assist with this issue)
You have given me renewed hope and convinced me that I need to take the next step in my new found addictive hobby and jump into enlarging and printing my negatives. It sounds like the results will be far more satisfying and I am excited by this prospect. The scanner I am using is a Plustek 7400 with updated SilverFast 8 software. I see what everyone is saying about scanner software behaviour adjusting itself to the exposure and contrast which can increase the grain as I have just been scanning my first colour film home developed in the Tetenal C41 kit and the auto Midtone and Contrast settings are swinging a lot more either way with each negative than it does with my B&W negs.

The SilverFast software does not have a preset for this new B&W film Bergger Pancro 400. Having tried every film in the list available on the software I have settled on the Kodak T400 CN setting which seems to give a reasonable result. The Plustek is a cheap old scanner I picked up for $100. I will get a decent enlarger first before worrying about upgrading the Plustek.
Regards
Robin.

 

[darinwc]

That is the main problem right now with film to digital process. The film scanners have not improved much in the past 10 years. Neither has the scanning software.

 

[samcomet]

Thank you Sam ( and thanks Darin and everyone else taking the time to assist with this issue)
You have given me renewed hope and convinced me that I need to take the next step in my new found addictive hobby and jump into enlarging and printing my negatives. It sounds like the results will be far more satisfying and I am excited by this prospect. The scanner I am using is a Plustek 7400 with updated SilverFast 8 software. I see what everyone is saying about scanner software behaviour adjusting itself to the exposure and contrast which can increase the grain as I have just been scanning my first colour film home developed in the Tetenal C41 kit and the auto Midtone and Contrast settings are swinging a lot more either way with each negative than it does with my B&W negs.

The SilverFast software does not have a preset for this new B&W film Bergger Pancro 400. Having tried every film in the list available on the software I have settled on the Kodak T400 CN setting which seems to give a reasonable result. The Plustek is a cheap old scanner I picked up for $100. I will get a decent enlarger first before worrying about upgrading the Plustek.
Regards
Robin.

Hiya Robin,
I wouldn't be too disapointed with the neg to scan process but I would posit an idea that if you do need the output as a digi file you might try just for comparison sake either or both:

Scan the silver print instead, when you get into the darkroom process (I get a way better result with the flatbed scan on my Epson film/flatbed);
Or
Have a go with the chromogenic B & W film. I personally do not like the results but then I'm an old ratbag codger. Chromgenic film is a B & W film that uses dyes instead of grain to produce the image on the substrate. It is a C-41 process (of the 1 hour colour variety) so not really a home darkroom process. The negs produced have no real silver grain per se so they might scan a tad better in you setup.

In my humble experiance too, that I would advise not getting too hung up on which preset is for which film stock. In my workflow I usually find somthing close to what looks reasonable and then tweek it by eye and save the results as "my" new preset.

Anyway best of luck!!!
Cheers,
Sam

 

[klownshed]

When scanning underexposed negatives, the software must increase the amplification digitally. The scanner lamp does not get any brighter. This also increases the apparent grain. Either from the existing grain or from dust in the optical system or digital noise.

You may find them more printable with a traditional darkroom.

+1. Underexposed negatives result in more grain apparent in the scan.

Wet printing will result in a completely different image.

The SilverFast software does not have a preset for this new B&W film Bergger Pancro 400.

This is compounding your problem. When you let the scanner decide how to scan you end up with everything averaged and you also lose information from the negative as when the scanner sets the black and white points it compresses the tonal range and effectively throws away detail. That's ok when the scanner gets it right and you don't need to adjust, but the scanner will often get things wrong.

You will get superior results if you turn off all the auto settings in the scanner and scan it 'flat'. This will result in a very dull, grey image but the file will contain far more tonal information.

You then edit it in your photoshop type software to make it look the way you'd like it to. The easiest and quickest way is to use the 'levels' tool and drag the black and white points until the image looks more or less right. You can then use the midpoint slider to adjust the mids or for finer control use the curves tool.

As you scanned it flat there is far more information in the file and this will result in smoother graduations. And less grain.

The scanner presets in silverfast are terrible.

Just as with wet printing in the darkroom, scanning requires care too.

Oh. And turn off sharpening in the scanner software. Sharpening should be the very last stage once everything else is perfect. Sharpening in the scanner will just make the grain even more apparent.

 

[markbarendt]

Just an FYI for those who are suggesting underexposure as a possible problem here. In this specific case the example of the offending grain is most prominent in the clouds and sky, the areas of the negative that got the most exposure, in fact obviously plenty.

If there were an underexposure problem the problem would show in the dark areas of the positive.

 

[klownshed]

Just an FYI for those who are suggesting underexposure as a possible problem here. In this specific case the example of the offending grain is most prominent in the clouds and sky, the areas of the negative that got the most exposure, in fact obviously plenty.

If there were an underexposure problem the problem would show in the dark areas of the positive.

When you scan an underexposed neg using the auto settings, the software tries to set the black and white points at the low end of the histogram. This usually ends up with crushed dynamic range as it compresses the data, making the graduations between areas of similar tone more coarse, showing off the grain in the sky. The sharpen algorithms then make them even more apparent. There is noise in the shadows, but the grain will still be most apparent in the brighter areas.

Try shooting a foggy scene. If you underexpose it and then scan on auto, the foggy areas (brightest in the image) will be the most apparently grainy areas, much more so than the grain in the shadows.

 

[markbarendt]

When you scan an underexposed neg using the auto settings, the software tries to set the black and white points at the low end of the histogram. This usually ends up with crushed dynamic range as it compresses the data, making the graduations between areas of similar tone more coarse, showing off the grain in the sky. The sharpen algorithms then make them even more apparent. There is noise in the shadows, but the grain will still be most apparent in the brighter areas.

Try shooting a foggy scene. If you underexpose it and then scan on auto, the foggy areas (brightest in the image) will be the most apparently grainy areas, much more so than the grain in the shadows.

While you may have a point for an underexposed shot of a foggy scene, that isn't the problem here.

We are looking at a well lit scene with decent detail all the way into the shadows.

 

[klownshed]

While you may have a point for an underexposed shot of a foggy scene, that isn't the problem here.

We are looking at a well lit scene with decent detail all the way into the shadows.

You said if the scene were underexposed the grain would be appear in the shadows. That's what I was replying to.

The grain in a scan is almost always most apparent in areas of sky or fog or any bright areas with small changes in tones and underexposing increases the chances of getting more grain from the scan.

Scanning on auto can massively increase the grain as it inevitably reduces/compresses the tonal range. Scanning it flat allows there to be much smoother gradients in large areas of sky, etc.

 

[markbarendt]

You said if the scene were underexposed the grain would be appear in the shadows. That's what I was replying to.

The grain in a scan is almost always most apparent in areas of sky or fog or any bright areas with small changes in tones and underexposing increases the chances of getting more grain from the scan.

Scanning on auto can massively increase the grain as it inevitably reduces/compresses the tonal range. Scanning it flat allows there to be much smoother gradients in large areas of sky, etc.

No, I said an underexposure problem shows in the shadows. That isn't about grain, it's about having enough exposure to get good well defined detail on the negative in the shadow areas.

When underexposed the shadow detail is marginal on the negative. When the negative has marginal shadow data and the software or the operator tries to fix underexposed shadow detail digitally you get 'digital noise' not film grain.

Completely different problems, completely different fixes.