Scanning Resolution Question

[interneg]

And it should be noted that Hasselblad/ Imacon scanners are not under any circumstances a 'drum' scanner - no PMT's, no fluid mount on perspex drum. They are 'virtual drum' with flexible holders, but are really just a very good CCD scanner. To refer to it as a drum scanner is fundamentally dishonest. I'm extremely familiar with them & while they don't necessarily have the learning curve of drums, they are outperformed by the better drum scanners.

As for 'I don't need a better scanner for 35mm because I shoot handheld'... let's just say that's one of the more laughably bizarre statements I've heard in a while.

[interneg]

There are clients of mine using this 100mb camera and stitching making monster files, I am worried my measly PS printing platform will need to be upgraded to handle these monster files, keeping and printing in 16 bit (though not critical over 8bit) means files over 1 gb which starts slowing down things.

Going above the 4GB mark is where things start to get really entertaining... One of those 50x65s hit 12GB in 16 bit I recall - bringing a pretty powerful computer to a crawl. Looking at building a new machine here too, with a decently serious GPU in order to handle those sort of files.

[Pere Casals]

And it should be noted that Hasselblad/ Imacon scanners are not under any circumstances a 'drum' scanner - no PMT's, no fluid mount on perspex drum. They are 'virtual drum' with flexible holders, but are really just a very good CCD scanner.

"are not under any circumstances a 'drum' scanner" yes, but better than most drum scanners, 4.8D for the X5. Hassy is Hassy.

As for 'I don't need a better scanner for 35mm because I shoot handheld'... let's just say that's one of the more laughably bizarre statements I've heard in a while.

It is not bizarre at all. You can test that for shure very easy. Just take a good DLSR and shot a resolution target handheld, with both VR ON and OFF, also with tripod. Then calculate the blur radius you have on sensor/film, it is a plain calculation, I think you should be able to perform, but on any doubt I can explain it to you.

I do that calculation often for industrial video systems that are on a machine with vibrations, sometimes a LED illuination delivers blur but a 1uS strobe freezes it very well. I use that for contactless metrology.

Once you have your on film blur radius you can guess how many scanning dpi you need. Anyway you can see it by eye without calculations, technical calulations are no need at all for art, but anyway doing it once in a lifetime is a good learning to know matters or not.

Regards

[faberryman]

PS edition also can make grain more or less sharp.

You can't make the grain more or less sharp in PS if the grain itself is not resolved by the scan, as is the case with the Epson flatbed.

With respect to camera shake, when I scan I would rather have sharp blur than blurry blur so I use a film scanner. But to each his own.

[Pere Casals]

You can't make the grain more or less sharp in PS if the grain itself is not resolved by the scan, as is the case with the Epson flatbed.

With respect to camera shake, when I scan I would rather have sharp blur than blurry blur so I use a film scanner. But to each his own.

Tabular grain (TMX, Delta) is not evident even in 35mm ...for LF not seen at all.

The particular case of big grain films, (HP5, Silvermax) are well seen with V700/850, and a sharpening (or softening) action with very small radius will adjust well grain depiction.

This an example with silvermax vs TMX with V750

https://www.flickr.com/photos/125592...posted-public/

https://www.flickr.com/photos/125592...posted-public/



You can find really good photographers like this one (that I like a lot and inspires me), working with grain and using V700

https://www.flickr.com/photos/558734...57633306014832

https://www.flickr.com/photos/558734...57633306014832

Of course with LF... no grain !!!

With respect to camera shake, when I scan I would rather have sharp blur than blurry blur so I use a film scanner. But to each his own.

"sharp blur" and blurry blur to me it's the same in terms of image quality. But "Sharp blur" (strange concept ) may show more grain.



I would like to add that grain depiction can be important in digital process: Amazonas team that edited Salgado's Genesis struggled a lot with it. Half of the shots were digital but they introduced artificial grain (with DXO filmpack, IIRC) to have consistence with TXP 645 shots, then printed it on Delta 100 8x10 sheets with a Kodak LVT Rhino, 4 images per sheet, and enlarged optically.

What I mean is that grain can be a digital postprocess concern, of great aesthetical complexity. And this also concerns how grain is scanned. I've been exploring all that with a lot of personal interest... but still I've a lot to learn...

[IanBarber]

Pere, how much testing have you done with Epson V series with regards to the required distance between the film and the scanner glass to achieve optimal sharpness from the scanner on Medium Format films or any size film come to that

[faberryman]

Tabular grain (TMX, Delta) is not evident even in 35mm ...for LF not seen at all.

I see grain in my 10"x15" (10x) darkroom enlargements from 35mm Delta 400, particularly in areas like the sky. The Epson V700 cannot resolve that grain, so similar size prints from those scans are not sharp; they look mushy. Scans at 3900 ppi clearly show the grain structure on screen and in the prints, and I don't use sharpening to enhance that grain. These are my actual results; they are not theoretical.

I would post comparative scans from an Epson flatbed and a 3900 ppi film scanner, but after doing my initial 35mm film scans on an Epson V700, I saw what they looked like, deleted them, and bought a film scanner. Again, if you are scanning large format, an Epson flatbed may be just the ticket, though it is no where near as good as an X5 or a drum scanner.

[Corran]

I think Pere is seeing grain aliasing. And worse his overly-aggressive unsharp masking is accentuating this grain. A smoother overall image can be achieved with higher-resolution scans - and yes, this applies to any format, because the film is roughly the same regardless of how large a piece it is (yes, enlargement ratio will play a part in what it looks like though). I have seen plenty of very grainy scans from 120 and 4x5, even with slow film (also important here is manipulations in contrast and highlights). "Resolving grain" is not as simple as seeing grain in your scans.

From what I've seen, grain aliasing looks more like random noise and less like film grain to me. Pere's 35mm silvermax shots clearly show this fuzzy noise in the scan that to me is a perfect example of aliasing, especially when exacerbated by USM.

[faberryman]

I think Pere is seeing grain aliasing. And worse his overly-aggressive unsharp masking is accentuating this grain. A smoother overall image can be achieved with higher-resolution scans - and yes, this applies to any format, because the film is roughly the same regardless of how large a piece it is (yes, enlargement ratio will play a part in what it looks like though). I have seen plenty of very grainy scans from 120 and 4x5, even with slow film (also important here is manipulations in contrast and highlights). "Resolving grain" is not as simple as seeing grain in your scans.

From what I've seen, grain aliasing looks more like random noise and less like film grain to me. Pere's 35mm silvermax shots clearly show this fuzzy noise in the scan that to me is a perfect example of aliasing, especially when exacerbated by USM.

Here's an example (not mine) of grain aliasing. It isn't pretty:



What you see on the left is multi-colored pixels; on the right, grain, or more accurately, dye clouds.

[Pere Casals]

I see grain in my 10"x15" (10x) darkroom enlargements from 35mm Delta 400, particularly in areas like the sky. The Epson V700 cannot resolve that grain, so similar size prints from those scans are not sharp. Scans at 3900 clearly show the grain structure on screen and in the prints, and I don't use sharpening to enhance that grain. These are my actual results; they are not theoretical.

Well... I'm not very interested in Delta or TMY grain, to the those grain structures are lacking character, to me it looks DSLR noise, while I love TX/TXP/HP5/FP4/Silvermax/APX and P3200 grains. For Delta and TMX I prefer to hide grain as much I can, so I can't tell.

I'm pretty sure that a Coolscan would deliver a better grain, but don't think that 2800 to 3900 dpi (say effective optical) is a big change for grain depiction.