"Photo Science", suggestions please!

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ChrisR
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"Photo Science", suggestions please!

Post by ChrisR »

I'm looking for suggestions.

I've been asked to do a short series in a secondary school on "Photo science". Victim age 11-14.
Group size may be 20, but they can work in pairs or groups.
One assistant.

6 x 1 hour slots. Format variable , but approximately:
  • A few Powerpoint screens showing theory on the science and/or what the camera's going to do.
  • "One I prepared earlier"
  • A demo
  • Have a go.
The idea is to integrate some biology or physics or maths, to produce interesting picture(s). Educational fun.

Some will have medium cameras, others only mobile phones.
Close-up /Macro photography will feature significantly I'm sure.
(I could lend some cameras, or have a couple on tripods. Come to think of it, I have about 10 digital cameras.)

I shall steal Brian's soap-film idea. Once we've got the boring old science out of the way they can have fun with coat hangers and bubbles.

Suggestions for sessions would be welcome. I have a bunch of ideas, but won't suggest now because that may steer.

I'll be able to borrow some standard school equipment, but we'll need to buy some things. Budget for all material is fairly low - some can't afford to pay.
We have Overhead projector, Smart Screen, Whiteboard, simple micropscopes, USB microscope.

Perhaps we can collaborate with knowledge/experience in this thread. Ideas evolve.. :) ?

(If anyone has a number of unwanted optical items, please pm me, we'll need multiples of some things.)
Chris R

zzffnn
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Post by zzffnn »

I would do this: https://youtu.be/NKVvp_PQkDk

It should provide excitement, photo/camera science, chemistry and physics.

A permanatently mounted crystal slide would work too, though less exciting.

Soap film would be great too, though it may not be as stable and be slightly more difficult to image?
Last edited by zzffnn on Sat Jan 21, 2017 6:32 pm, edited 1 time in total.
Selling my Canon FD 200mm F/2.8 lens

ChrisR
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Post by ChrisR »

Good Idea Fan!
I can see I can get salicylic acid (and ascorbic acid, which makes birefringent crytals), but not acetylsalicylic acid. Does that work too?
I assume aspirin tablets don't work? :lol:

I have a couple of polar microscopes. Could get some mobile phone sheets of polarizing material.
Is the fun visible without a microscope?
The bigger the crystals the better. Suggestions anyone?
I vaguely remember Hypo fixer (sodium thiosulphate) made large crystals. - ?

I've seen someone make the UK "Union Jack" "Union Jack" flag the right colours by using sticky-tape retarders, but the science is a bit hard for an 11 year old!

Perhaps pictures of something shiny using crossed polars... :-k
Chris R

zzffnn
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Post by zzffnn »

Chris R,

I think all those chemical that you mentioned will work. Aspirin may be the cheapest? The acetyl part only makes it more dissolvable in alcohol.

Any transmitted light + polarizers should work, microscope is likely not necessary (though more convenient? Depends on what you already have, I guess).
Last edited by zzffnn on Sat Jan 21, 2017 6:31 pm, edited 1 time in total.

Beatsy
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Post by Beatsy »

ChrisR wrote:...Could get some mobile phone sheets of polarizing material.
Is the fun visible without a microscope?
Stressing plastic from CD and cassette cases between the cheap pol sheets should generate some interesting patterns that could be photographed without needing a microscope. Very "hands on" and destructive too - perfect for kids (even us "grown up" ones :)

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Post by ChrisR »

Fan - are the crystals big enough to be seen without aid?


Steve, That's a good thought.
Polarization gets conceptually difficult for the age group quite quickly. Take one sheet and shine light through it, tick.
Take another sheet at 90º and the light stops, tick.
Take a third and place it between them at 45º, and light goes through again. Spooky!
Explain to an 11 year old..?

If it's a sunny day, then we'd just head outside :).


Polarization would enter one day's session producing stereo pictures.
Plus red/green, crossed eyed, straight (viewer required). Pol glasses are cheap enough. I have r/g ones.
And they can have fun going boss-eyed.
Chris R

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Post by zzffnn »

Chris R,

The crystals should spread out across at least half of a regular microscope slide (25 mm x 38 mm), if there is enough material. No cover slip is necessary. Some area may have less color than other areas though.

You may want to prepare crystal spread in a vertical rig (hence microscope may be more convenient), to prevent messy dripping and uneven spread, if you are doing video or time lapse.

I have tried 5x total magnification (1x objective and 5x eyepiece on a microscope) and it imaged polarized crystal (spread) size slightly more than a US penny (19.05 mm in diameter). So I assume less than 5x total magnification would also work, as long as there is enough crystals spreading over.
Last edited by zzffnn on Sat Jan 21, 2017 6:31 pm, edited 1 time in total.

ChrisR
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Post by ChrisR »

Thanks Fan, useful info.
That means something like a cheap "macro adapter" on a phone, would do it, even if it's only something like 0.2x!

We could measure the effect of a cooling fan or a heat source, on rate, and crystal morphology.

Time lapse is intended to be another session! I have to think of "Science" things which happen in say 5 - 20 minutes.

Open to suggestions - Drosera ...? Venus Flytrap? Does mimosa come as a pot plant? Ice cream melting...! Pollen tubes - would have to be something like Alder at this time of year. Sugar crystallizing from molten, fst and slow.
Electroytic capacitor swelling and bursting, LiPo battery exploding...


Keep them coming. I have a fair list, but I'm sure others will come from a different direction.
Chris R

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Post by LordV »

Some thoughts.

1. Refractive properties of liquid in air and air in liquid using say glycerol

2. Making cross-eye stereograms

3. Rigging some kind of event trigger eg sound or optical. to take a photograph

4. If crocuses are in flower then doing a time lapse of an opening flower. A picked flower bud can be kept cold but will open in about 5 mins in a warm room

Brian v.
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Post by ChrisR »

Thanks much Brian. SOme unknowns on my part:

1: Small square tank of glycerol with a "bent looking" rod in it, ok (Or a quarz glass rod which "disappears" because the RIs match)

BUT air in glycerol - I don't follow :?:

2: Cross eye stereograms certainly, but Rik's report is that at first, few can "see" them . Therefore I need to make or buy some simple viewers for parallel viewing. I know he's mentioned one which works but iirc there were problems getting them.

I'll need to talk about 3d TV too, which is developing outside my knowledge..
There's photography + fun + perspective there, + physiology of the eye.

3: Absolutely. I have some cheap little lasers and phototransistors, also infrared and Ultrasonic sensors. The kids can connect them up and connect to a hacked Android remote shutter, for a camera-phone trap. Electronics + fun + a camera.
I made a simple audio trigger on a breadboard: microphone + amplifier + rectifier + optocoupler.

4. Great - I didn't know flowers could be that fast. it'll be nearer to summer. Will ask about flowers.

I intend to watch the water engorging the plant, with flourescent dye, so it glows in the dark/UV (Ok, it needs light to transpire ;) ).


4b :For larger plants we may be able to inject a plant at the leaves and see one dye in the phloem, and put another in the roots and see it inthe xylem.

4c:
The poikilohydric nature of the helical mosses is watchable but again I don't know how fast they react. Water/dye NOT through roots.

5: We can do some close-up type macro of course to demonstrate optics.
If we can get away pfrom phone cameras we can use bokeh.
LEDs places around to giv bright OOF blobs, then Butterfly shaped cutouts in front the lens to go all girlie.

6: we can do time-lapse with reflective spots while somene does a tennis serve, or use a strobe. Wonder if I can train the cat?

7: We can go from spots to stick men to cartoons and CGI, though I'm not aware of any ideal free software.

8: there's always stitching and perspective lessons which ensue. They'll know about panos, but probably not 2 dimensional stitches. Circular perspectives, fisheyes.. Telecentricity for measurements, and reversed perspective.

9: I have a FLIR and an IR night-scope but they're a bit naff, and they'd all want one.

10: there's loads of maths stuff. Whizz a light around your head and use a short shutter speed to work out how fast...

11. I was a plumber - so there's always Schlieren photography.
Chris R

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Post by LordV »

Chris with the glycerol I was thinking of refraction using droplets of glycerol perhaps on a glass slide with a flower or something underneath. The refracted image appears in front of the image of the drop.
In reverse bubbles in a glycerol mixture in a thin clear bottle or perhaps between two glass slides will also refract but the image appears behind the bubbles.

Brian v.
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Post by ChrisR »

LordV wrote: The refracted image appears in front of the image of the drop.
It does?
What I'm imagining now is a van-Leeuwenhoek-microscope. Great for a lesson.
I'm thinking pre-cut sheets from Al cola cans could be folded into shape, rather than cardboard, with self-tapping screws.

Now I need a lot of very short focus lenses. CDs, Laser pens, phone cameras, webcams?

Does anyone know if the lenses one can get to put over LEDs would do?

I think disposable camera lenses, even if I could get enough, would be longer.

If I can get soda glass rods, then there's a chance to melt something -always cool.
Chris R

Andy Davies
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Other ideas

Post by Andy Davies »

How about a prism to split light as in Dark Side of the Moon?

Shine light through smoke in a bell jar to show Brownian motion. Place camera in bell jar and remotely trigger it. Diffusion of smoke through a hole in a barrier in the jar?

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Post by johan »

No specific suggestion, but there's a lot of fun to be had with UV fluorescence I think that you might be able to make one lesson out of? Ie banknotes, tonic water, bananas, blood, there are all sort of things that look funky under UV lighting. or dabble UV paint on your face which you can't see unless lit by UV - all sorts of fun and games to be had :). You're more than welcome to borrow my UV torches for the lesson too of course
My extreme-macro.co.uk site, a learning site. Your comments and input there would be gratefully appreciated.

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