Film Qualities and Scanning

[SilverGlow]

What film qualities will scanning cancel out? And if film qualities are marginalized too much, then what is the point of shooting film if that image will be digitized later as part of the image mastering workflow?

I'm new to scanning, but not new to film or digital.

Perhaps you can enlighten me on this?

Thanks

 

[sanking]

Not sure what you mean by the term "cancel out".

Grain is almost always a problem with film scans versus digital. On the other hand, digitized film normally has much higher resolution than film.

For example, P45+ Phase Back, cost at about $40K USD, easily beats MF and LF film in terms of grain, but even MF film scanned on film scanner (LS-9000, Imacon or drum scanner) easily beats the P45+ back in terms of resolution.

With appropriate post-processing I am fairly sure that I can beat P45 phase back overall (balance resolution and grain) with top quality MF equipment (Mamiya 7II) and high quality scans. LF of 4X5 and more easily beats P45+.

Course, there are creative possibilities available with digital, be is DSLR or P45+ phase back, that trumps film.

Sandy King

What film qualities will scanning cancel out? And if film qualities are marginalized too much, then what is the point of shooting film if that image will be digitized later as part of the image mastering workflow?

I'm new to scanning, but not new to film or digital.

Perhaps you can enlighten me on this?

Thanks

 

[nsouto]

Apart from the grain issues already mentioned and which can be worked around, the only other thing I can think of is dynamic range.

Unless you are working with a top quality film scanner, you may be reducing the dynamic range present in film by scanning it. This is actually one of the most compelling reasons to use a dedicated film scanner as opposed to a flatbed.

Another thing to keep in mind is that output of the scan should be kept at 48-bit colour (each colour represented by up to >65000 different levels) until at least all desired target colour balance is achieved.

In principle, you should strive for good colour balance straight out of the scan process, by balancing the scan lighting itself.

Some scanners don't allow that, which means you got to do it after the scan. That's called "post-processing".

If you are working with only 24-bit colour output (where each colour is represented by only 256 distinct levels), you post-processing colour balancing might be limited.

There are extensive technical explanations for this.

Suffice to say you will observe banding of large colour gradients if you apply any extensive colour re-balancing to a 24-bit colour image.

This is NOT to say ALL your colour has to be handled at 48-bit! Only up to the point where you are done with colour balance corrections, for whatever reason you might undertake those.

 

[SilverGlow]

Apart from the grain issues already mentioned and which can be worked around, the only other thing I can think of is dynamic range.

Unless you are working with a top quality film scanner, you may be reducing the dynamic range present in film by scanning it. This is actually one of the most compelling reasons to use a dedicated film scanner as opposed to a flatbed.

Another thing to keep in mind is that output of the scan should be kept at 48-bit colour (each colour represented by up to >65000 different levels) until at least all desired target colour balance is achieved.

In principle, you should strive for good colour balance straight out of the scan process, by balancing the scan lighting itself.

Some scanners don't allow that, which means you got to do it after the scan. That's called "post-processing".

If you are working with only 24-bit colour output (where each colour is represented by only 256 distinct levels), you post-processing colour balancing might be limited.

There are extensive technical explanations for this.

Suffice to say you will observe banding of large colour gradients if you apply any extensive colour re-balancing to a 24-bit colour image.

This is NOT to say ALL your colour has to be handled at 48-bit! Only up to the point where you are done with colour balance corrections, for whatever reason you might undertake those.

Guys, thanks for all the info.

So then am I to understand that scanners will output to 8-bit/channel color and not 12, 14, 16 or more? Perhaps I read wrong? It is my hope my scans will result in at least 12 or 16 bit/channel depth. I'm thinking to buy a Nikon 5000 film scanner, but still mulling it over...

 

[DrPablo]

even MF film scanned on film scanner (LS-9000, Imacon or drum scanner) easily beats the P45+ back in terms of resolution.

I believe you, but I haven't ever seen any tests that demonstrate this. Would you be able to reference a direct comparison of the two? This test between drum scanned 4x5 and the 39MP Phase One seems to favor the drum scanned film, but it's hardly a slam dunk. And I doubt MF would fare as well as the 4x5 film in this test.

http://www.luminous-landscape.com/essays/Cramer.shtml

Also, not to be overlooked is the ISO / grain relationship. Fine, Velvia 50 and Tmax 100 have very high resolution and very small grain. But NPZ and Delta 3200 do not, and I'd think that both grain and resolution would disproportionately favor digital capture as you increase ISO.

o then am I to understand that scanners will output to 8-bit/channel color and not 12, 14, 16 or more? Perhaps I read wrong? It is my hope my scans will result in at least 12 or 16 bit/channel depth.

It's variable, but most scanners these days will output to 16 bits/channel. I have a Howtek 4500 drum scanner that outputs to 12 bits/channel (dumped into the 16-bit mode in Photoshop). But honestly if you have a well-exposed negative and a high end scanner then I don't really see what 16 bits really gets you. If you have a lot of editing, correcting, and digital manipulation to do, then the higher bit depth helps, but for a trivial tweak here and there it's probably just wasted scanning time and wasted file size.

On the other hand, with my consumer scanner (a Microtek i800), I really DO need that higher bit depth because the color accuracy of the scanner is mediocre and the images are soft, noisy, and low contrast (compared with the drum scanner), so I need to do much more digital manipulation to get it looking right.

 

[sanking]

No, I can not point you to a published comparison but I know this to be fact from some comparison testing I did with a couple of friends, which included high quality 6X7cm film (Mamiya 7II), high quality 4X5, and P45 phase back. Our original intention was to write up the results and that may still happen, but we are way behind schedule in doing so. From my perspective the following is true.

1. High quality MF film, drum scanned, beats the P45 in terms of resolution, but loses in terms of grain. MF film easily wins on cost, but loses in terms of overall creativity to MF digital back.

2. 4X5 LF film easily beats the P45 in both grain and resolution, though you may have to print larger than 30X40" to see the difference. LF film easily wins in terms of cost, but MF digital back offers more overall creativity, especially on a camera with movements.

Clearly factors such as film grain, speed, and quality of the scanner have to be carefully factored in when comparing digital with film scans.

Sandy

I believe you, but I haven't ever seen any tests that demonstrate this. Would you be able to reference a direct comparison of the two? This test between drum scanned 4x5 and the 39MP Phase One seems to favor the drum scanned film, but it's hardly a slam dunk. And I doubt MF would fare as well as the 4x5 film in this test.

http://www.luminous-landscape.com/essays/Cramer.shtml

 

[nsouto]

So then am I to understand that scanners will output to 8-bit/channel color and not 12, 14, 16 or more? Perhaps I read wrong? It is my hope my scans will result in at least 12 or 16 bit/channel depth. I'm thinking to buy a Nikon 5000 film scanner, but still mulling it over...

Most modern scanners can output at more than 8bits per colour. Nikon's Coolscan V can output at 14 bits and the 5000 and 9000 can output 16-bit colour. And of course they can also do 8-bit, it's a scan time option.

I do know my 4990 Epson flatbed can do 16-bit as well and so do the V700 series.

Higher bits per colour are useful if you expect lots of colour correction after the scan. As mentioned, this can be the case with scanners that don't handle colour balance that well or don't have a facility to correct colour balance by changing the scanning lighting itself.

All three Nikon Coolscans can change the lighting colour as they use three colour leds with independently controlled colour channels. This makes it possible to use only 8-bit per colour for the vast majority of average balanced photos. Using 8bit colour speeds up the scanning process by allowing smaller file sizes.

For the odd cases, it's very handy to have the ability to use more than 8-bit per colour: you get more headroom to make changes and adjust colours before banding becomes a problem. It does not need to be done for every image, of course. But when you need it, you'll be glad you got it.

 

[pellicle]

Hi

I believe you, but I haven't ever seen any tests that demonstrate this. Would you be able to reference a direct comparison of the two? This test between drum scanned 4x5 and the 39MP Phase One seems to favor the drum scanned film, but it's hardly a slam dunk. And I doubt MF would fare as well as the 4x5 film in this test.

http://www.luminous-landscape.com/essays/Cramer.shtml

In support of Mr Sankings argument I thin that this test a useful comparison (even if it is LL).

I commonly use black and white in my 4x5 (although ADOX rather than Acros, but if I were still in Japan I'd be still using Across)

 

[pellicle]

Hi

For the odd cases, it's very handy to have the ability to use more than 8-bit per colour: you get more headroom to make changes and adjust colours before banding becomes a problem. It does not need to be done for every image, of course. But when you need it, you'll be glad you got it.

actually I now routinely use the highest bits I can get out of my scanners even if there is no "need" for head room. I find that it gives much less posterisation effects on subtle tonal graduations like skys or stuff like that.

This sky was a case in point (even though the provia sheet was well enough exposed)

 

[nsouto]

That is a gorgeous shot, pellicle! If you don't mind me saying. The light is just awesome!

Yes, I agree with you on using as much as one can. Most of the time one can get away with 8bits, but cases like your shot definitely ask for more.

It saves on disk and scan time to use 8bit. Not as much of a drama with 35mm, files are relatively small. But with 6X6 at 4000? Yikes! I get almost 450MB at 16bit and 225MB at 8bit, 6X7 is even worse... BIG difference!

Granted and without a doubt: some types of shots - yours is a good example - may indeed deserve 16bit, though.

Like in anything else it's all in the specific and individual cases, isn't it? Very hard to come up with a "one size fits all"...

Which brings me back to Silverglow's question:
yes, you can survive with 8-bit colour scans,
and yes, when you need 14 or 16bit you'll be glad you can use it!