Snow Exposure advice needed

[Deleted member 88956]

Use orange or yellow filters, just do not eat yellow snow.

And I've just listened to Frank Zappa, coincidence ?

 

[Paul Ozzello]

Hi Lachlan,

I’ve re-read your posts numerous times and I’m still not entirely sure how to interpret the comparator curves for Delta 100. Am I making the correct following assumptions :

• The aim is to capture detail in zones 1 – 8 , which is about 7 stops of exposure range. Zone 0 is pitch black, above 7 we can’t really differentiate.
• These zones are best captured on the straight portion of the graph and we want to avoid exposing on the toe or shoulders.
• The steeper the curve the better the tonal separation.
• The blue line shows where the tones fall onto the graph if we expose at box speed (iso 100 - for a given development “recipe” based on time and temperature). Decreasing film EI would increase exposure and shift the blue line up the curve, while Increasing EI would shift it down. In my case since I've been exposing at iso 80, I have been moving all my snow tones way into the shoulder where there is very little separation of tones and reduced contrast.
• Delta 100 seems to perform much better in T-Max developer, but it seems like there is a loss of acutance compared to X-tol.

Which leads me to some questions :

1. Is the x-axis measured in EV ? On the T-Max graph could I theoretically expose from EV11 to EV36 (12.5 stops). Is this possible ?
2. Or does the length of the blue line indicate the range of density possible in a single exposure ? For T-Max this would be (1.3 – 0.1 = 1.2). Does the length of this line change depending on development times ?
3. Is the halfway point on the blue line = zone 5/the incident light meter reading ?
4. Delta 100 in X-tol gives a max density of 2.00 and the shoulder begins at 1.4, while T-Max developed in T-Max gives a higher maximum density of 2.4 and a shoulder starting at 2.3. Does this mean T-Max in T-Max has much more exposure latitude that Delta100/X-tol ?
5. Why are there only 11 zones in the zone system ? Can’t film capture more than this ? I thought film could capture ~14 stops of light.
6. Since I’m drum scanning and the drum scanner can scan a density close to 4, ideally I want the widest range of density as possible in my negatives right ?

Paul

Xtol 1+1 and Delta 100 seem to cause quite serious highlight roll-off if you start to push your exposure up the scale - I've attached screenshots of the comparator curves available here. There are caveats - I recall finding some of the Fotoimport results have been developed for slightly wayward times etc, but they do give a useful snapshot. The other point is that as you extend development times you'll steepen the midrange and enhance the roll-off, exaggerating the results into the highlights that are already causing the muddying of details in the higher scale which you are currently dealing with. It also explains why I was a bit puzzled by the Xtol results you were getting compared to what I know Delta 100 does with D-76 and Rodinal. I would however say that my suggestion of TMax developer stands for what you are wanting to do - but that T-Max 100 and T-Max developer might together act to kick the tonal separation up a notch - again the Fotoimport results may seem a bit confusing, but if you adjust the dev time for TMax 100 so the midtones match (9-10 mins, going by Kodak's data, I reckon - see pg.8 and pg. 9), you'll get significantly stronger - even exaggerated beyond linear - highlight separation than Delta 100 and TMax developer give. It's for situations like this that TMax 100 was designed - it just requires a bit of common sense in its usage, rather than the often very casual/ outright sloppy approach people had to the exposure & processing of 100 speed films in the (now quite distant) past - TMax is older than I am!

I'd avoid the Rollei film - it's an Agfa aerial recon film that is a fair bit slower than box speed at sea level - and it doesn't seem to hold linearity through the highlights particularly.

 

[Paul Ozzello]

Fuji seem to have published some data for Acros II - it looks like it does upsweep a bit in the highlights, even in D-76 (Microfine is more or less Perceptol/ Microdol-X, Super Prodol is more or less Microphen from what I recall). Might avoid Xtol as it seems to be intended to dampen highlight density to make negs 'easier' to print.

I should have the film in the next day or two, I'll try the T-Max first.

Worth noting that I don't think Sammallahti uses anything particularly exotic (I did find a reference somewhere to him using XP2 Super) - but his overall printing style tends to differ from what you are after - unless I am much mistaken?

Sammallahti is one of several photographers that inspired me early on as an artist, particularly his ability to capture the depth of a landscape. I accidentally discovered his work at "Le Mois de la Photo" in Montreal 20 years ago. It was a particularly good exhibit that also featured the work of Edward Burtynsky (another favorite), but after all these years I hope I've developed a style of my own. I do a lot of retouching in Photoshop to make my images look like they were printed on platinum and transform the lighting to remove any notion of time. But I think certain cameras do have inherent signatures that are recognizable across various artists (notably Lee Friedlander's use of a Hasseblad SWC).

Unfortunately several of my snowy landscapes are obviously not processed or exposed correctly and are giving me a very hard time to print. I've always avoided getting too involved in the technicalities of film development preferring to spend more time making images but I think it's time I get a better grasp on characteristic curves of films and how to optimize the placement of tones with proper exposure and development.

Thank you for all your help and advice so far.

Paul

 

[Craig75]

honestly, i'd be checking the camera shutter speeds and metering before worrying about film curves because what you have described in the negatives sounds like gross over exposure. already - low contrast and grainy snow = exposure already on the shoulder and being overexposed imo and possibly by 3 stops or more.

I'd bracket a scene -4 -3 -2 -1 0 +1 +2 +3 changing shutter speed and the same again changing aperture this time as something doesn't sound right with the camera to me from you description of negatives.

 

[osella]

I’ve re-read your posts numerous times and I’m still not entirely sure how to interpret the comparator curves for Delta 100. Am I making the correct following assumptions

I don’t think you can necessarily equate those graphs to actual exposure values as they may be relative values not absolute.

If you are looking for separation of tones in the highlight region you want a steeper slope. With xtol and delta 100 the highlight region flattens out compressing tones effectively reducing contrast.

Tmax 100 in Tmax Dev can potentially give you the opposite where the slope increases in the highlight region.

 

[Sirius Glass]

honestly, i'd be checking the camera shutter speeds and metering before worrying about film curves because what you have described in the negatives sounds like gross over exposure. already - low contrast and grainy snow = exposure already on the shoulder and being overexposed imo and possibly by 3 stops or more.

I'd bracket a scene -4 -3 -2 -1 0 +1 +2 +3 changing shutter speed and the same again changing aperture this time as something doesn't sound right with the camera to me from you description of negatives.

Endless, mindless eternal testing is really not necessary for anyone other than Zonestas. Take a deep breath. It is not that complicated. Even I have been successful take photographs of snow and lived to be able to tell about it. Besides there are some great people out there that calibrate light meters, inside or outside cameras.

 

[Paul Ozzello]

but if you adjust the dev time for TMax 100 so the midtones match (9-10 mins, going by Kodak's data, I reckon - see pg.8 and pg. 9), you'll get significantly stronger - even exaggerated beyond linear - highlight separation than Delta 100 and TMax developer give

The Kodak development times for TMAX100 developped in TMAX don't look right

https://125px.com/docs/film/kodak/f4016_tmax_100-2018.pdf

It looks fine for iso 100/Normal exposure 68F, 7.5 minutes - using a dilution of 1:4

but for iso 200/Pushed 1-stop 68F, 7.5 minutes doesn't specify a dilution - implying FULL strength ?

This is different than what is posted on the massive development chart
which states that in both cases dilution remains the same (1:4)

https://www.digitaltruth.com/devcha...%TMax+Dev%&mdc=Search&TempUnits=F&TimeUnits=D

 

[Paul Ozzello]

honestly, i'd be checking the camera shutter speeds and metering before worrying about film curves because what you have described in the negatives sounds like gross over exposure. already - low contrast and grainy snow = exposure already on the shoulder and being overexposed imo and possibly by 3 stops or more.

I'd bracket a scene -4 -3 -2 -1 0 +1 +2 +3 changing shutter speed and the same again changing aperture this time as something doesn't sound right with the camera to me from you description of negatives.

The camera has been CLA'd, and shutter speeds are identical to my backup camera, and shutter speeds sound right, so I think they are properly calibrated. Same for my light meters and digital thermometers. I am overexposing a little by setting my EI to 80 and basing exposure on an incident light meter reading. My negatives of snow/white-out scenes with gray/white skies aren't particularly dense, just VERY flat. There definitely isn't a full range of tones in the actual scene, so what I'm trying to figure out is how to get the maximum amount of contrast (contrast index ? ) from the film in these particular lighting situations.

 

[Craig75]

The camera has been CLA'd, and shutter speeds are identical to my backup camera, and shutter speeds sound right, so I think they are properly calibrated. Same for my light meters and digital thermometers. I am overexposing a little by setting my EI to 80 and basing exposure on an incident light meter reading. My negatives of snow/white-out scenes with gray/white skies aren't particularly dense, just VERY flat. There definitely isn't a full range of tones in the actual scene, so what I'm trying to figure out is how to get the maximum amount of contrast (contrast index ? ) from the film in these particular lighting situations.

ah well if they arent dense then something is going wrong somewhere else imo - you should be able to get the contrast in image software - the snow should be sitting on the highest contrast area of the film so any contrast should be easy to correct in software - unless something has gone fundamentally wrong in the chain be it the camera, the developing, or the scanning.

if the negatives look correctly exposed but really flat - it has to be either the film is wrecked, the developer is expired / exhausted, or temp control is wrong or time is far too short.

looking at the hut shot there should be maybe 6 stops between shadowed side of hut and snow is sun so negative shouldnt look flat

 

[Lachlan Young]

The Kodak development times for TMAX100 developped in TMAX don't look right

https://125px.com/docs/film/kodak/f4016_tmax_100-2018.pdf

It looks fine for iso 100/Normal exposure 68F, 7.5 minutes - using a dilution of 1:4

but for iso 200/Pushed 1-stop 68F, 7.5 minutes doesn't specify a dilution - implying FULL strength ?

This is different than what is posted on the massive development chart
which states that in both cases dilution remains the same (1:4)

You can largely ignore the massive dev chart - it's often a weird mix of bad transcription and strange ideologies .

Kodak often spec the same dev time for box speed and a +1 push - not worth going into here, but it's more for preventing the inexperienced screwing up negs. If not spec'd assume standard dilution for TMax dev - aka 1+4.

What's most useful for your purposes is the chart at the bottom right on pg.8 and top left on pg.9. The chart on pg.8 shows characteristic curves for various Contrast Indices. Chart on pg.9 gives time/ Contrast Index relationships. Kodak tend to give their recommended 'box speed' times for a CI of about 0.55, a little below the ISO standard of 0.6. I would definitely compare & contrast to the curves given for D-76 at the top right of pg.8 (Xtol tends to give similar shapes). If you are working in a fairly flatly lit scene, I'd probably try 12 mins in TMax 1+4 and see - it may be not enough, it may be too much. But it should get you a starting point. EI will have to be determined by trial & how you prefer to meter.

 

[Lachlan Young]

With xtol and delta 100 the highlight region flattens out compressing tones effectively reducing contrast.

I think that Xtol sets out (in part) to try and counteract the two major bad habits of photographers - ie the tendency to underexpose (thus the shadow speed boost) and the tendency to overdevelop (thus it rolling off highlight density) - with the intention of improving the number of printable negs.

 

[DREW WILEY]

I can probably shoot and print snow and ice scenes as good as anybody living or dead, and have never even once needed to bracket an exposure! T-Max films will give you a little more reach into deep shadows than ACROS at box speeds. But if you use ASA50 for ACROS, you'll get most of a high contrast scene up on the straight line. I primarily use staining pyro developers to rein in sparkly highlights. If you are, on the other hand, working with a flatly-lit scene, and your negatives are coming out too flat also, they simply aren't developed long enough. Stick with the old adage, Expose for the shadows, develop for the highlights. But if you're trying to shoot TMX100 underexposed at 200, well, that's simply not a good idea to begin with. I'm not going to comment on any fashion of digital printing; it's not my style.

 

[MattKing]

The Kodak development times for TMAX100 developped in TMAX don't look right

https://125px.com/docs/film/kodak/f4016_tmax_100-2018.pdf

It looks fine for iso 100/Normal exposure 68F, 7.5 minutes - using a dilution of 1:4

but for iso 200/Pushed 1-stop 68F, 7.5 minutes doesn't specify a dilution - implying FULL strength ?

Kodak recommends that if you are using T-Max developer, you should use normal processing - do not change development if you under-expose T-Max 100 by one stop (EI of 200).
That recommendation is on the first page of that data sheet.
Every increase in development (push) has a potential deleterious effect on highlight rendition. Kodak's position is that for one stop under-exposure, the benefit in the shadow areas from a one stop push development is less than the damage to the highlights.
One thing to remember though is that this assumes a subject with a normal range of tones, and lighting conditions that provide normal contrast. If your purpose is not to deal with low light levels and under-exposure, but rather to increase contrast - an expansion rather than a push - than information about push processing isn't what you need. You are looking for information about expansion development. For a single grade of contrast increase, something like a 15 percent increase in development time and a very small decrease in exposure - 1/3 stop? - would be a decent place to start. I don't often do that, so I'd suggest asking about that specifically, in the hope that others who do use the technique can chime in.

 

[Paul Ozzello]

I'm attaching some sample images of my negatives (1 good and 2 bad) with their corresponding prints, along with mock ups i originally took with my iphone.

This is a well exposed/processed negative (ei 80, xtol)

And the processed image :

This is one of the PROBLEM negatives, lots of snow, clouds, very little contrast.

The Processed image after scanning

The iPhone mock up - which has much more detail and contrast in the snow

Second problem negative of frozen bay with large ice structures, cloudy sky lots of snow.

The scan is so flat I just don't have anything to work with. Here is the iPhone mockup

So despite the very flat lighting conditions, the iphone is still capable of capturing a fair amount of texture in the snow that I can barely capture on film...

The densities of the bad negatives look darker than they acutally are, the density of the skies are about the same as the good negative.

 

[MattKing]

The densities of the bad negatives look darker than they acutally are, the density of the skies are about the same as the good negative.

This tells me that you are over-exposing. The highlights in the skies are in the shoulder, and the mid-tones and shadows are crowding up against them.

 

[Lachlan Young]

This tells me that you are over-exposing. The highlights in the skies are in the shoulder, and the mid-tones and shadows are crowding up against them.

Yep, the lowest shadow densities are way above base + fog.

 

[MattKing]

FWIW, that overly dense negative might be perfect if you were seeking something like this:

 

[Paul Ozzello]

This tells me that you are over-exposing. The highlights in the skies are in the shoulder, and the mid-tones and shadows are crowding up against them.

Yep, the lowest shadow densities are way above base + fog.

So definitely overexposed and not overdeveloped ? Is my first negative also overexposed ?

I'm using an incident meter, Sekonic L-508, which gives an identical reading to my Minolta Flashmeter V. The camera's shutter speeds are correct : when I had the camera CLA'd it was tested with transparency film and the exposures where spot on. So I'm not sure why they are so overexposed. Unless they are way overdeveloped, but the frame numbers on the film also look ok.

I'll try bracketing with reduced exposure to dermine what iso I should shoot.

If you are working in a fairly flatly lit scene, I'd probably try 12 mins in TMax 1+4 and see - it may be not enough, it may be too much. But it should get you a starting point. EI will have to be determined by trial & how you prefer to meter.

Is this applicable ?

 

[Craig75]

meter error, didnt set camera up right after metering, shutter is way out, or aperture is stuck - as those look heavily overexposed and everything's been lost in the void of shoulder.

could the cold be affecting the shutterspeed ?

 

[Lachlan Young]

So definitely overexposed and not overdeveloped ? Is my first negative also overexposed ?

First neg is fine - deepest/ black shadows & film base+fog are same density. Other two negs are maybe stop + over. I wouldn't necessarily go trying the contrast expansion processing if the first neg is close to what you are wanting tonally. The only immediate thing I can suggest (if everything else is the same) is that the cold is making the voltage from the batteries drop in the Noblex, the drum runs slower & thus overexposes - or something atypical like that

 

[osella]

Looks like some overdevelopment too, it can be a tricky balance between exposure and development when trying to expand contrast on really flat scenes.

I usually use Delta 100 at EI 100 when making negatives for Platinum printing. The negatives can get really dense and blocked up quickly when overexposed and developed.

 

[Paul Ozzello]

could the cold be affecting the shutterspeed ?

is that the cold is making the voltage drop in the Noblex, the drum runs slower & thus overexposes.

I suppose both are possible.

But I'm only having the problem with 5-6 negatives that contain mostly snow. The remaining 74 images were also taken in frigid temperatures of scenes with significantly more contrast. They are all properly exposed like the first sample and scanned great, and the prints are beautiful.

Maybe my light meter is getting overwhelmed by the snow ?

At any rate I'm going to try the Delta 100 with xtol again and bracket by lowering my exposure in 1 stop increments. I'll also do the same with a roll of TMAX100/TMAX to compare, and a roll of TMAX100/TMAX developed for 12 minutes.
I'll also bring my Sony A7R to compare exposures.

 

[Paul Ozzello]

I usually use Delta 100 at EI 100 when making negatives for Platinum printing. The negatives can get really dense and blocked up quickly when overexposed and developed.

I get the impression xtol might not be the best developer for this film under these lighting conditions, what developer are you using ?

 

[Paul Ozzello]

FWIW, that overly dense negative might be perfect if you were seeking something like this:

Hah!

I was able to salvage the image by adding some glacier ice texture from another negative to the lower left side of the image and it came out better than expected. Still needs a little fine tuning but I'm pleased so far :

 

[Sirius Glass]

1. Did you take a light reading of the sky? Even part of the sky messes up reflectance readings.
2. An incident meter would have given you the correct light reading.
3. Have you had your cameras CLA'd and light meters calibrated?