Best way to capture a 35mm slide with an iPhone X?

May 28, 2018 7:36 PM

I am working with some images on slides that are part of a library collection. I’d like to get a copy of a few of them, at the highest quality possible. I’m not allowed to use a slide scanner and the slides can’t leave the room they’re in. I’m allowed to use a light table and my iPhone. I’m thinking maybe I should get a good lens to add to my phone? Any recommendations appreciated.
posted by brbmaroon to Technology (9 answers total)

Best answer: One thing you want is a scanning app like Microsoft Lens. This will make sure that you get a non-skewed rectangle. (I’d love to get a recommendation about which Lens-like app is most optically precise.)

For lenses, I’m very happy with the Moment lens system. Would telephoto be the best application?
posted by blueshammer at 7:53 PM on May 28, 2018 [1 favorite]

Best answer: Depending on what you're going to use the scans for, a secondary lens might be worthwhile. The Wirecutter's recommendation here (which is the same as blueshammer's) seems like a good option.
posted by Making You Bored For Science at 7:57 PM on May 28, 2018 [1 favorite]

Best answer: Flagship smartphone cameras are pretty amazing now, I think you could get a good image with just your phone. It probably can't focus close enough so that the slide fills the entire image but even if you stand back a bit and need to crop out some of the photo, the resolution is high enough that you should still get a good quality final image. A tripod will help you get as possible and line things up so you have an easier time cropping later. Try taking photos of postage stamps and see if that's good enough.

If you buy a lens, I think you want a macro lens, which will allow your phone to focus on closer objects, rather than a telephoto. Someone who knows lenses better than me should weigh in on this. The thing to watch out for though is distortion towards the edges, especially in cheap lenses. I haven't tried the Moment lenses but the reviews are good. Take a picture of a piece of graph paper so you know if/where the lens starts to distort the image.
posted by yeahlikethat at 6:21 AM on May 29, 2018

Best answer: Another thought: My phone does strange things when taking pictures of fluorescent lights and computer monitors. You might want to test out your phone and/or bring a different model of phone as a backup, depending on how mission critical this is.
posted by yeahlikethat at 6:55 AM on May 29, 2018

Best answer: How complicated are you willing to get, what equipment will they let you bring, and how much are you willing to spend? Given the constraint of "it can't leave the room" I'd bring in a DSLR, macro lens, and slide duplicator. The slide duplicator is key. It's a piece of metal that screws onto the front of the macro lens, positions the slide at the correct distance, and diffuses the light going into the slide. Here's the Nikon version, although there are cheaper third party options:

https://www.nikonusa.com/en/nikon-products/product/slide-copy-adapters/es-1-slide-copying-adapter-for-52mm-thread.html

If you have a DSLR (or can borrow one) the macro lens will probably be the most expensive part of this.

Here are a couple threads on a photo forum about it:

https://www.dpreview.com/forums/post/57208771
https://www.dpreview.com/forums/thread/3975801
posted by unix at 8:02 AM on May 29, 2018 [2 favorites]

Best answer: In my experience, macro lenses for smartphones are too close/too aspherical for this purpose, but I might be surprised.

Obviously nothing is better than a DSLR and slide duplicator.
posted by blueshammer at 8:47 AM on May 29, 2018

Best answer: Does the library offer reproduction services? It might be worth it to just pay the fee to get a nice clean scan rather than spending money for a lens/jig set-up you might not use too often. I say this as an archivist who scans 35mm slides and transparencies for researchers all the time. Some times the longest way 'round is the quickest way home, if you know what I mean.

If you are using a camera phone, the most important thing I think will be keeping the camera parallel to the slide, regardless of the lens used, and making sure light is not hitting the slide surface from some other source. You could use a tiny cardboard box with no bottom to hold your phone/camera steady over the slide (remember the light is coming up from below) and just crop out the black space.

Also, a clean sheet of copy paper placed between the slide and the table can diffuse the light nicely and avoid visual artifacts from florescent lighting in the light table. New led light tables (sold as tracing tablets or whatever) can be really bright and diffuse; we use one for photographing glass lantern slides and it works great.
posted by gyusan at 9:10 AM on May 29, 2018

Best answer: Nothing to add except high end dslr and lenses are available for short term rentals. I have had good results with lensrentals.com and friends have used borrowlenses.com

A quick search shows these two rental houses do not have slide adaptors in stock but that’s probably the cheapest part of the camera/macro lens/slide duplicator trilogy.
posted by sol at 10:53 AM on May 29, 2018

Best answer: I think the easiest and cheapest way to do this would be with a film scanner app. I haven’t used any myself so I can’t recommend one, but if you google either film scanner app or negative scanner app there are quite a few out there. You might have to do some photoshop correcting later but that isn’t too difficult.
posted by mygothlaundry at 9:23 PM on May 29, 2018