Grain on large format (scanned negative): hp5 plus vs tmax 100

[hsandler]

I've scanned a fair bit of 4x5 on an Epson V750 at optimal height at 2400ppi, but I don't have any examples posted online at full resolution to show you. I like HP5 at box speed or FP4 at box speed for even finer grain. Honestly, you would have to print pretty big to see grain in a large format image. As others noted, you are not really scanning grain on a flatbed scanner; it can't resolve grain. You are just seeing aliasing of the grain into larger apparent clumps the size of a scanned pixel. So I shoot these two films largely because they are the lowest cost Ilford films. For medium and smaller format I use Ilford Delta for finer grain.

[Pere Casals]

As others noted, you are not really scanning grain on a flatbed scanner; it can't resolve grain.

You scan grain with a flatbed !!! it resolves true film grain. Of course it resolves better HP5 grain than TMX or Delta 100.

It is true that a drum may deliver sharper grains, and small grains are very aliased with a cheap flatbed.

An epson resolves some 0.01mm, and many grains are way larger. Another thing is bromide crystals in the emulsion, those are seen with electronic microscopes

[mmerig]

You scan grain with a flatbed !!! it resolves true film grain. Of course it resolves better HP5 grain than TMX or Delta 100.

It is true that a drum may deliver sharper grains, and small grains are very aliased with a cheap flatbed.

An epson resolves some 0.01mm, and many grains are way larger. Another thing is bromide crystals in the emulsion, those are seen with electronic microscopes

Kodak defines grain as "A particle of metallic silver or a cloud of dye in a photographic emulsion. Exposed silver halide crystals in raw emulsion that become grains in the photographic process." See Print Grain Index, E-58. C. E. Kenneth Mees, in his book "From dry plates to Ektachrome", discusses grain sizes and what it takes to see them. According to Mees, a grain particle itself is about 1 to 5 microns in diameter (the silver halide crystals).

What we see as grain in a scan is noise and grain clumps. If individual grain particles were "way larger than 0.01 mm", the resolving power of film would be poor.

[Pere Casals]

Kodak defines grain as "A particle of metallic silver or a cloud of dye in a photographic emulsion. Exposed silver halide crystals in raw emulsion that become grains in the photographic process." See Print Grain Index, E-58. C. E. Kenneth Mees, in his book "From dry plates to Ektachrome", discusses grain sizes and what it takes to see them. According to Mees, a grain particle itself is about 1 to 5 microns in diameter (the silver halide crystals).

What we see as grain in a scan is noise and grain clumps. If individual grain particles were "way larger than 0.01 mm", the resolving power of film would be poor.

Please see this document, Page 2 http://www.tmax100.com/photo/pdf/film.pdf This is nice info, a doc worth to keep.

It shows pictorial film grain is 10 to 30 microns this is 0.01mm to 0.03mm. (In microfilm type film, adox cms 20, it is way smaller)

My view is that those grains in the 0.03mm range are well depicted by a cheap (V800, at top performance settings, 0.01mm) flatbed, those grains in the low end (0.01) are mostly blurred by a the cheap flatbed but well depicted by a high end flatbed or drum scanner. A very cheap flatbed (V600) it even blurs the big grains.






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Aliasing/blurring the big grains it also may happen during Ps edition with resize, rotate, etc. And of course it will happen when digitally printing.

Dealing with grain in the hybrid workflow (small formats) it's not easy if structure counts.

Also note that those scanners that are limited in resolving power by the dpi in the sensor like Nikon LS 9000 or Hassy X5 may deliver aliasing when working at top prformance, these are scanners sporting a very good lens but using a 8000pix sensor. A flatbed like a V850 will never deliver grain aliasing because resolving power limitation come from the optics, the sensor (40,000 pix) outresolves the lens by an x2 factor, the V850 covers always 5.9" so the lens performance is always stressed. The EPSONs may blur the grains, but will never have aliasing.

This effect can be compared with the lowpass optical filter many DSLRs had to prevent aliasing. Today the smaller pixel size makes the LPF less useful (and not placed) because the sensors outresolve the lenses is most of practical situations.





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Regarding film resolving power it all depends on contrast, at 1:1000 is when a BW film may go well beyond 100lp/mm, in that situation what is working is very, very small grains that are only exposed at some +3 overexposure, and that are formulated in the emulsion for the curve shoulder shape.

The doc says:
Silver-halide crystals are 0.2-2.0 um
Color Clouds are 10-30 um
BW T grains are 15-25 um

Time ago I made a personal/informal test. I made a tinny cross with a marker in a negative, I observed the fladbed and drums scans, and then I also observed the cross in a microscope at x400. I was very interested for knowing how grain was digitally printed and what happened with scanners. I could identify the same particular grains in the cross and in the scan, so I could compare. It is an excercise I'd recommend to those interesed in grain structure, anyway this is a least concern in LF, but in rolls it can a powerful aesthetic tool for some.

[rpagliari]

I dont have enough technical background for this. However, I do see different grain when scanning different type of negative, and it always increases as asa goes up.

How could that be just digital noise?

[Pere Casals]

I dont have enough technical background for this. However, I do see different grain when scanning different type of negative, and it always increases as asa goes up.

How could that be just digital noise?

You only have digital noise in the crazy high high densities, this would be in the extreme Velvia shadows, this is electronic noise.

Your V550 delivers 1500dpi effective, if you get the V800 you will have 2800dpi effective in the transverse axis and some 2300dpi in the vertical axis, so some 2500dpi effective average, this is a big leap forward concerning grain.

IMHO the V800 is very capable for LF and even MF, for 35mm film you may want an additional 35mm cheap Plustek.

I most practical situations the V800 nearly matches camera/film performance for LF, and for LF grain is usually not a concern.

For roll film you may want to exploit grain structure. To me TMax or Delta flat grains are not interesting for the aesthetics. IMHO those were products intended to minimize grain, not intended to deliver a nice structure.

HP5, FP4, TX, and TXP are a different war. Those films evolved during many decades and are still there because they have an strong aesthetic culture backing them.

After releasing TMax kodak planned to discontinue TX. A riot was assembled, kodak managers didn't know why photographers were buying TX...

TX/TXP delivers more grain in the shadows than in the mids (if scene microcontrast not masking grain), delivering a dramatic mood. HP5 has its peak grain in the mid grays, delivering a particular atmosphere.

Format modulates grain. 35mm shows a lot, 645 vs 6x7cm is not the same. And LF hides most grain.

So, to me, for grain wait until you have the 800 and see. IMHO you'll be happy with MF and LF scans. If wanting a better depiction for 35mm than you'll need an additional cheap Plustek 35mm, if not wanting to spend a lot in a Plustek 120.

Note that V850 bundles a silverfast version that is Multi-Exposure capable, which is good for Velvia extreme shadows, with V800 you can purchase that software feature in the future if you want. This is an important difference I see V800-850. V850 have the lenses coated, but I guess that this is not much noticed.

[rpagliari]

You only have digital noise in the crazy high high densities, this would be in the extreme Velvia shadows, this is electronic noise.

Your V550 delivers 1500dpi effective, if you get the V800 you will have 2800dpi effective in the transverse axis and some 2300dpi in the vertical axis, so some 2500dpi effective average, this is a big leap forward concerning grain.

IMHO the V800 is very capable for LF and even MF, for 35mm film you may want an additional 35mm cheap Plustek.

I most practical situations the V800 nearly matches camera/film performance for LF, and for LF grain is usually not a concern.

For roll film you may want to exploit grain structure. To me TMax or Delta flat grains are not interesting for the aesthetics. IMHO those were products intended to minimize grain, not intended to deliver a nice structure.

HP5, FP4, TX, and TXP are a different war. Those films evolved during many decades and are still there because they have an strong aesthetic culture backing them.

After releasing TMax kodak planned to discontinue TX. A riot was assembled, kodak managers didn't know why photographers were buying TX...

TX/TXP delivers more grain in the shadows than in the mids (if scene microcontrast not masking grain), delivering a dramatic mood. HP5 has its peak grain in the mid grays, delivering a particular atmosphere.

Format modulates grain. 35mm shows a lot, 645 vs 6x7cm is not the same. And LF hides most grain.

So, to me, for grain wait until you have the 800 and see. IMHO you'll be happy with MF and LF scans. If wanting a better depiction for 35mm than you'll need an additional cheap Plustek 35mm, if not wanting to spend a lot in a Plustek 120.

Note that V850 bundles a silverfast version that is Multi-Exposure capable, which is good for Velvia extreme shadows, with V800 you can purchase that software feature in the future if you want. This is an important difference I see V800-850. V850 have the lenses coated, but I guess that this is not much noticed.

Thanks a lot for the info. I'm using a Plustek with 35mm. So, in the end, I'd better upgrade my epson, as I do MF and LF as well..

Thank you,

[mmerig]

Please see this document, Page 2 http://www.tmax100.com/photo/pdf/film.pdf This is nice info, a doc worth to keep.

It shows pictorial film grain is 10 to 30 microns this is 0.01mm to 0.03mm. (In microfilm type film, adox cms 20, it is way smaller)

My view is that those grains in the 0.03mm range are well depicted by a cheap (V800, at top performance settings, 0.01mm) flatbed, those grains in the low end (0.01) are mostly blurred by a the cheap flatbed but well depicted by a high end flatbed or drum scanner. A very cheap flatbed (V600) it even blurs the big grains.

The Tim Vitale article you linked to says the following:

"The term “film grain” is often incorrectly used to describe the “fundamental” particles in a chemical-based photographic image."

and

"Grain is a regular repeating noise pattern larger than the fundamental particles. Some mistake film grain for the image-forming elements in film.

and

"Many Kodak and Fuji “popular” publications, including much of the popular photographic literature (magazines), also make the mistake of referring to fundamental film particles as filmgrain. This further propagates the imprecise usage of the term."

C. E. Kenneth Mees, who worked for Wratten and Wainwright, then Kodak, was involved with decades of research in photographic materials. His definitions differ from Vitale's, and I would hardly call Mee's books "popular" in the sense that Vitale uses. In essence, Mees (in his book From Dry Plates to Ektachrome Film) defines grain as the fundamental particle, or silver halide crystal (in the 1 micron range). The 3-dimensional clumpiness aspect, or structure of the grain particles, he calls granularity, and its appearance as graininess.

This is somewhat semantic, but intuitively, a grain of sand is analogous to a silver halide crystal in emulsion, and it makes more sense to call the individual particles grain.

[Pere Casals]

This is somewhat semantic, but intuitively, a grain of sand is analogous to a silver halide crystal in emulsion, and it makes more sense to call the individual particles grain.

We have silver-halide crystals before development and metallic silver clumps after, we may call grain to both, but they are different things.

My view is that photographers and industry always call film grain to the metallic silver particles we have after development:



"Fine grain" or "coarse grain" always refer to that... Me, I use "silver halide crystals" (or simply crystals) to refrer the "fundamental particles" in the emulsion (a suspension in fact) before development, but when I learn DIY emulsion recipes for my dry plates I find some "grain" word usage with the crystals.

It has to be noted that good technical literature always use crystal for silver halide particles and never grain, for example you will find epitaxial or tabular crystal growth depending on the pAg factor (silver concentration in the addition), a technician-scientist will never say grain for that, IMHO.

It has to be noted that with processing the "fundamental particles" (halide crystals) disapear. The shape of the clump depends on solvent effect, infectious development etc, but the individual crystal shapes are not there anymore, in fact the crystals disolve during development or fixing.

My view is that we should say crystals for silver-halide crystals, as we always are in a technical context when mentioning that then better if we say the real concept, and it's better to leave the grain word for the metallic silver that is mentioned everywhere in general film photography for developed film.


Anyway when scanning we cannot go wrong with semantics, crystals are destroyed in the processing. ...so for sure we speak about the metallic clumps.

[interneg]

[Mees] calls granularity, and its appearance as graininess.

And it is the rendering of this characteristic in low contrast areas (smooth grey sky tones for example) that is a tough test for an optical system's MTF performance. Epsons & most consumer flatbeds fail at this. At 2000ppi & with good MTF performance (aka, high end CCD of various sorts, PMT drum scanners, camera scanning too), you will be able to render this detail proportional to overall resolution. The weird mush from consumer flatbeds that becomes a horrid noisy mess when sharpened is not a reasonable rendering of a film's granularity/ grain character.