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Comment by WalterBright | Hacker News Reader

I (and I've noticed this in others my age) still have a lingering thought that photography is expensive, and to conserve 'film'. Back in the day, even with slides, the finished cost per slide was about a buck each. It's just hard to dispel the habitual thought "is this shot worth taking?"

I'm still getting used to the ability to snap a pic and casually text it to a friend instead of trying to describe it.

I just downloaded a phone app that turns it into a scanner, complete with OCR. It's not as good as my flatbed, but it's incredibly convenient.

I feel like I'm living in the future.

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Film is expensive but its still unbeatable in terms of dynamic range and details, especially if you go to larger formats than 35 mm.

I know. But I never was a good photographer, and digital photography has improved to the point where it's more than good enough for me.

My dad had a rangefinder Leica, and he swore by it. But I look at the pictures he took, and they're often slightly out of focus, grainy, under/over exposed, etc. I'm sure great photographs can be taken with a Leica, but you've got to be a great photographer to get them. But for sure they were better than the brownie he had before :-)

That's not really true anymore. While large format film may still have a slight resolution advantage IF you have high resolution lenses to match, most high-end sensors have better dynamic range than film (~14-15 stops vs ~13 stops).

> most high-end sensors have better dynamic range than film (~14-15 stops vs ~13 stops)

Film is the one with 14-15 stops. Plus its automatic S-shaped gamma curve, with gentle roll-off of the highlights, makes it easier to produce pleasing images. Movies, TV shows, and commercials that were shot on 35mm film in the 80s and 90s usually look better than the digitally shot ones today.

> look better than the digitally shot ones today

Probably because modern directors cannot resist mucking about with the palette so it is all blue and orange. If it's a period peace, they make it all sepia brown. They've reverted to the two-strip technicolor from the 1920's. Arggh.

Oh yeah, the infamous teal-and-orange palette, haha

> While large format film may still have a slight resolution

For 4x5 format it's not "slight resolution" advantage, it's a major resolution advantage. The most expensive sensors these days go in the range of 50~80 M pixels, 4x5 goes way beyond that if you want to use pixels to reproduce the kind of details it provides. That's why film is still used for stuff like very large posters.

90 Mpixels at 9m by 5m (if the sensor matches the format) would be sqrt(2) Mpixels per metre.

That's a dot-pitch of 1400 dots-per-millimetre or 36000 dpi; standard magazine print is 300dpi.

I really can't believe that something higher than that can be useful resolution for billboards unless you're cropping to a very small section of the full image. The stretching of the image with the glue is going to give you lots of distortion, never mind the ridges they usually have in them. http://graphicdesign.stackexchange.com/questions/3651/what-d... suggests a max working ppi of 75 for an actual reproduction of ~9dpi for a billboard.

A very large poster that you want to see close up I can imagine doing at 600dpi, maybe even 1200dpi; but you're going to need a magnifying glass to see that pixelation with normal eyesight I feel.

Even for film reproduction other errors in the process would seem likely to wash out any higher resolution, like dust on the lens in the cinema [do they have some sort of laser cleaning mechanism??], or indeed dust in the air in the cinema?

E&OE.

The caveat here is that large format has rather shallow depth-of-field, and if you stop way down then diffraction limits your resolution. There is somewhat of a resolution advantage from moving to larger formats, but it's not as large as you'd think when comparing to an equivalent depth-of-field with a smaller format.

The counter-caveat is of course that large format is often shot using camera movements that allow the line of focus to be creatively placed to make the most of the smaller depth of field, so stopping down an equivalent amount is not always necessary.

Off topic, but would you mind naming the scanner app?

Several showed up in the top business category, I picked one at random. I don't wish to endorse something I haven't used much nor have a basis for comparison.

One thing about its operation that pleased me was it did a much better than expected job of removing the distortion from the page, one thing you won't get from just a photo. I did like the OCR feature, too.

The others claimed to do the same thing.

Almost all apps seem to handle page orientation and correct it. However, I haven't come across any which can handle page curvature (like scanning a page from a book, instead of a single page document).

This one seems to do a credible job of fixing the curvature (what I meant by distortion).

Microsoft's Office Lens is pretty good. There's also TinyScanner.

CamScanner has been excellent for me. Anything less than $5 is a great deal for it.

i'm old, and i still feel that way and unconsciously hesitate to take multiple shots. Along those lines I get a brief flash of worry when someone calls me on the phone, 'long distance', because its so expense.

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