[roywiggins]

As optimistic as I am about photogrammetry and other 3D-scanning technology, I'm leery of calling it "preservation" or letting you "recreate" artifacts.

It captures shape and texture, but that's all. It's hollow. You can't take a core sample of a 3D scan, you can't X-Ray a 3D scan, you can't smell it or touch it; you can't tell if there's anything inside and you can't carbon-date it. It can't capture how pliable or brittle the object is or how dense it is. A high-res scan of the Mona Lisa can't actually be used to recreate the Mona Lisa. Short of nanoscale replicators, there's information missing.

[jfoutz]

Of course, the real one will be blown up, sooooooo. Hanging on to the copy of the copy of the copy worked ok for books. it's infinitely better than nothing.

[roywiggins]

There's an awful lot of value in a particular book-as-object that you lose in a copy, especially in pre-Gutenburg manuscripts:

- What script was it written in?

- How was it bound?

- What shape and size is it?

- Huge roomy margins or small tiny margins?

- Is it actually a palimpsest with another text underneath?

- Who owned it?

- How old is it?

And so on. If someone just writes down the text and burns the book, you've preserved the text but thrown away an awful lot about the people that produced and used the book.

A 3D scan might preserve 100% of aspect A, but 0% of aspect B, in which case it's exactly as bad as no scan if what you care about is aspect B.

[jfoutz]

Just so i understand, your point is it's much better to have nothing, than having a poor copy of the original object?

That makes, well, not much sense to me. but ok.

[roywiggins]

I mean that a lot of circumstances, having a picture/scan/copy only slightly diminishes the loss if the object is destroyed, and the existence of 3D scans etc shouldn't be confused with preservation of the original.

Obviously, take pictures and make 3D scans of everything! It's a great way to make unique objects available (to some extent) across the globe. But they're more aids to study than actual backups. Objects haven't been "saved" by being scanned; they're saved when they're actually preserved. A 3D scan of the Buddhas of Bamiyan would have only kinda sorta have ameliorated their loss.

[jfoutz]

Ah! gotcha. we were talking past each other. i was worried about the incidental damage from war and destruction by zealots, you're talking more about general preservation.

[toomuchtodo]

> A high-res scan of the Mona Lisa can't actually be used to recreate the Mona Lisa. Short of nanoscale replicators, there's information missing.

Baby steps. 100 years ago, I'm sure no one considered 3D scanning and 3D printing might ever exist. The next 100 years are going to be just as fun.

[solipsism]

Exponentially more fun!

[dogma1138]

And? if you are looking at a good reproduction of the Mona Lisa do you feel anything less?

There are tons of items that cannot be displayed to the public in fear of damaging them this can help to create a more accurate replica that can be easily displayed at a fraction of the cost.

Just so you know museums have been displaying replicas for decades (if not longer) as many items were too fragile to display, many "original" items that you might see in a museum are in fact replicas carefully crafted, some museums go as far as commission high end manual reproduction paintings if the original is too fragile to display.

And while reproduction paintings are rare natural history museums are filled with replica's those dinosaur fossils are not the actually fossils found in the ground, those are cast and hand finished to look good for the display and the casts often do not even come from a single fossil as a full fossil is almost a unicorn.

[mchahn]

> that cannot be displayed to the public in fear of damaging them

I saw the Mona Lisa at the Louvre on vacation. It was being displayed on a wall like any other painting but it had a big sign, saying no flash photography. There was a large crowd in front and there was a constant flashing from cameras. I wanted to yell at everyone but it wouldn't have done any good.

[viraptor]

Was that the original? I remember seeing Lady with an Ermine in Poland - really thick glass in front, dark room, people reminding you about the flash before going in. And I imagine that's not even remotely as important painting.

[mchahn]

> Was that the original?

Yes. It was 30 years ago so they have probably improved the protection since then.

[roywiggins]

Reproductions are awesome as aids to study and for education, no question. Scan everything and make it available in virtual & physical museums! There are huge gains from that. A faithful reproduction of an ancient Egyptian coffin lid is probably nearly as good, from an educational point of view, as the real thing.

But you're not going to be able to take that reproduction coffin lid, put it in a CAT scan, and find a 3000-year-old fingerprint.

http://www.independent.co.uk/news/science/three-thousand-yea...

[dogma1138]

Of course not but there are other good uses for reproduction and that if they are good enough you can gain insight from actually touching and handling them. Humans gain quite a bit of information from touching things, the lack of touch is actually felt in some fields like astronomy that have now started to experiment with 3D printing staler objects based on observational data and mathematical models to gain additional insight into various objects.

"The success of our work and easy identification of previously unrecognized physical features highlight the important role 3D printing and interactive graphics can play in the visualization and understanding of complex 3D time-dependent numerical simulations of astrophysical phenomena."

http://arxiv.org/abs/1503.00716

And while you won't be getting any fingerprints or trace material of a reproduction sarcophagus more people could see it, be inspired and you can actually use them in touch exhibits which open a whole other world for allot of people including the blind.