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Flat bed vs DSLR scanning


Exactly.
 
Alan Edward Klein said:
Regarding 35mm, I suppose the v850 cannot provide sharpening as good as a drum scanner. But it does a pretty good job certainly acceptable for the web.
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Acceptable? Sure, totally acceptable.

My point is that, even at web-sizes, the increase in clarity from a really good scanner will be evident. And this is illustrated by the girl/model image i uploaded above.


The oversharpening of the negative is readily evident.
 
Now i will show an example of a DSLR scan with no oversharpening.

Full image (downscaled).




No scanning artifacts visible.

100% crop of the full-res image. You can check out how the grain (dye clouds) resolved -without being artificially pronounced on the downsampled image- and, again, there's no oversharpening on the image. Every fine detail is resolved.

 

Wouldn't that depend if the film is flat or not. The glass on the V850 film holders is there to keep the film flat for scanning. The problem with the built-in glass though is it tends to pick up more dust.
 
Digital sharpening changes the image, based on statistical data and relatively reliable algorithms.
It doesn't reveal detail that is hard to see but otherwise there. It interprets what is there, and adds more based on statistical assumptions.
It certainly makes a lot of scans look better. But it can make the file a less accurate copy of the original.
Here is a scan of a pinhole negative, with relatively little sharpening - it looks reasonably similar to the negative.




And here is a sharpened image of the same digital file, with a little bit of contrast tweaking.




And finally, here is a nice and pretty positive of the scan, sharpened and adjusted to taste.





A carefully made darkroom print will usually appear less "sharp" than the last version, although unsharp masking techniques can be used to add apparent sharpness.

But in all cases, sharpening adds something that isn't already there.

FWIW, every single method used to digitize film will disrupt the acutance of the original - it is inevitable in any duplication process. Some digitization processes are less disruptive than others. It is appropriate to do some sharpening, to help offset that disruption.
 

These comparisons are but a very small part of the overall 4x5 image equating to around the size of a 35mm shot. You can see the whole picture and what part was magnified in the first part of the thread.

Howtek 8000 Drum vs. Epson V850 flatbed scanners

Here's a comparison between Howtek HiResolve 8000 drum scanner and Epson V850 flatbed. Negative is mine, Tmax 100, processed normal by North Coast Photo dip and dunk with Clayton F76+ developer (similar to Kodak D76). Taken on a Chamonix 45H-1, Schneider Symmar APO 150mm with B+W orange...
www.largeformatphotography.info
 

In my sample, the Howtek was not sharpened but the V850 was sharpened a lot. So I understand your point. But if the end results due to required sharpening is not noticed, what difference does that make? After all, isn't that what all sharpening is doing even on digital photos? MAking things that are blurrier into something that's sharper to the eye?
 

Depends on whether it matters to you how faithful to the original your scans are.
If you don't mind the fact that scanning loses detail and sharpening adds different detail, not otherwise present in the film original, then go for it.
 
MattKing said:
Depends on whether it matters to you how faithful to the original your scans are.
If you don't mind the fact that scanning loses detail and sharpening adds different detail, not otherwise present in the film original, then go for it.
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But if you look at my samples between the Howtek and the sharpened Epson, you can't see any difference in the final details.
 
Alan Edward Klein said:
But if you look at my samples between the Howtek and the sharpened Epson, you can't see any difference in the final details.
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Sure I can - they look different.
The Howtek is likely to be more faithful to the original film, while the sharpening on the Epson adds a pleasing facsimile of detail that looks nice in the scan.
Whether the differences matter to you depends on what you are looking for.
 

100 lp/mm is 5000+ dpi.
 
MattKing said:
[sharpening] interprets what is there, and adds more based on statistical assumptions.
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Hm... I wouldn't put it this way. There are several sharpening techniques. Your statement describes "smart sharpening/upsampling" in Photoshp. But the good ol unsharp mask is basically just contrast adjustment. It's quite literally takes what's already there and makes it more visible without adding anything at all.
 

Do you have an Epson V700 or V800 series scanner? If not, please don't tell those of us who have one, what it can and cannot do.

Other people who use these scanners find they get better image quality with the V800 style holders, which flatly contradicts the review you link. The review claims, with zero evidence, that the ANR glass used in the holders somehow refracts the various wavelengths of light differently-- but I'm not aware of how a flat piece of non-curved glass can (or plastic) do that. Perhaps Nodda Duma can chime in.

Most of the people who are very eager to tell me how terrible my Epson scanner is, do not in fact own one. Most of them have never used one. Getting the most out of an Epson flatbed takes time and effort, and frankly, the people at filmscanner didn't really try very hard-- or, as I've said before, if they did, they didn't document it. They didn't even mention if their unit was new, with the transport locks engaged, or a "review unit", passed around from reviewer to reviewer, with unknown treatment. Because if you really, really want bad scans from an Epson, pack it up, and ship it across the state with the transport locks disengaged.
 

The sharpening technique I prefer for film is frequency separation. It allows me to separate out the level of detail I want to sharpen, and apply as much sharpening as I like to that detail, without over-sharpening anything else. You're right that it's just altering the contrast between areas, but at least I have more detailed (ha) control over the process.
 
grat said:
Source?
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Math. A 35mm negative is 36mm long. 100lp/mm means you need 7,200 pixels for 36mm AKA 1.42 inches.

7,200/1.42=5070

I will say that 100lp/mm is firmly outside of the realm of real world benefits. Combination of lens quality, grain, shake and low contrast detail, plus the fact that 95% of photos I take are crap anyway result in... let's just say I'm not sure I have a single negative which can benefit from scanning at this resolution. It only works for staged shots like this, but even that one is HP5+ and, therefore, downsampled to 6,400px on the wide side.
 
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When the true 5000dpi-resolution dedicated film scanners appeared on the market, many claimed this was useless and that the already existing scanners (circa.2400dpi) were good enough, that there wasn't enough detail in the frame anyways. And then the results proved otherwise.

In the very same way that when 6MP digital cameras appeared, many people claimed they were already surpassing 35mm film in quality and being comparable to medium format...

When you scan a frame with a really good film scanner, you're gaining clarity of detail. It doesn't just mean that you're resolving up to the tiniest hair of detail, that's a minor benefit. The MAJOR benefit is that the MTF curve of the whole system is higher for all frequencies. In plain english, the clarity of the whole image will improve, not just on the parts that have tiny details.

Again, this is perfectly illustrated by the portrait/model picture above.
 

Exactly. On both observations.
 

Prove me wrong.....literally.....but it seems to me that Epson scanners have a focusing problem. You gotta do "this" to get best results. I've never seen anything about Canon scanners needing focusing.

Maybe I'm naive. Mi dos centavos.
 
Paul Verizzo said:
Prove me wrong.....literally.....but it seems to me that Epson scanners have a focusing problem. You gotta do "this" to get best results. I've never seen anything about Canon scanners needing focusing.

Maybe I'm naive. Mi dos centavos.
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Esos dos centavos tienen muchísimo valor...
 

That erroneously supposes that you need two pixels to resolve an intersection with a line pair. That is never ever true unless we are talking completely synthetic images.

Even with the best of sharpening and edge detection tech and a monochrome sensor, you need at least 3 pixels to resolve a line. Quite possibly more depending on contrast and exact shape and orientation.

With a bayer sensor things gets much more complicated, and even more complicated when we have multicoloured dots (sand, brick, berries, freckles, etc. Almost any natural image texture will have tiny subtle colour changes.

Flavio81 is completely right in that any photo will benefit in sharpness with better scanning. Contrasty high frequency tonal changes happens everywhere. Almost any transition between an object and background for example.
 
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Helge said:
Flavio81 is completely right in that any photo will benefit in sharpness with better scanning. Contrasty high frequency tonal chances happens everywhere. Almost any transition between an object and background for example.
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Thank you so much, i was feeling frustrated that few could see the obvious despite evidence

I really felt like Mugatu...

 

Of course, they look different. Contrast and other adjustments are different in each sample. But the sharpness and details of both match very closely. Everyone can make their own judgment. I'm curious what others think.

In any case, I don;t disagree that the Howtek scans should be better than an Epson. What surprised me, at least with 4x5 Tmax 400, was how nicely the Epson did. Most people looking at the comparison didn't see any difference. Of course, if you're pixel peeping, you might see something, But photographers don't present two shots next to one another for viewers to compare. They only show one, If that one is close to the other and passes muster, no one cares about pixel-peeping differences. That's just stuff we argue about.

Screen shot compares scanners at 100 percent after sharpening by Alan Klein, on Flickr
 

Much of what we actually see is the contrast between adjacent details of an image - in many cases very small, very adjacent details.
All of the sharpening techniques increase that contrast - sometimes accentuating differences that we can already perceive, and in some cases creating such differences, where there were no perceivable differences before.
It is the latter situation that I reference when I talk about sharpening "adding" detail.
 
But Matt, does it really matter? It's all illusion manufactured in our brains. So the sharpening is really adding contrast to the edges (acutance). It's not really adding more resolution. That's fixed by the sensor or film.

Of course, a drum scanner resolves better than a flatbed. So in that case it should be more naturally "sharper". Of course, how large you blow up the final image matters. Extra resolution only matters with larger final prints or displays because the eye can't resolve the small lines anyway. So contrast (accutance) sharpening becomes so important.

I suppose my samples would not look so good on a large print. Of course, if I was going to make one, I would have my film professional scanned with a drum scanner first. But for small prints and the web, the Epson is pretty good.
 
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