Seed germination time lapse project

[bass_junkie83]

Spring has sprung and at school my daughter is learning about baby animals and blossoming trees and all that. So I thought it would be a nice little project for her if we were to get a small fish tank, fill it with soil and plant some seeds tight up against the glass so she can see them grow.

Naturally, things escalated and I thought if we are going to this effort why not also photograph it and see if we can make a time lapse, and having not done this before I thought it might be worth recording the process here.

First up was sorting out a camera. I don't want to use mine, a Fuji X-T3 as I don't want it unavailable for other things. The only other camera I have that has been sitting unused at the back of a cupboard for a few years is an Olympus XZ-10 compact, if I can get that to work then great!

First issue is controlling the shot intervals, which after a bit of research online it seems 10 minute intervals should be about right. Being a fairly basic compact, this feature is not native to the camera, but I was able to find out that it can be used with an intervalometer, so thanks to ebay I got myself this.



The next issue to solve is powering the camera. It may need to be left running for 3-4 weeks at a time depending on what seeds we decide to grow so battery power clearly isn't going to cut it. The camera will run and charge while being powered via the usb port, but this is already being used by the intervalometer. Olympus never made a mains adapter for this camera so I thought to make one, but one thing I wasn't confident about was cutting up a lithium battery to convert to a dummy battery, but fortunately these were available from aliexpress.



So with that, all that was left was to sort out the power supply which actually took two attempts.
The battery is rated at 3.7V, which I assumed would be voltage at full charge and that the camera would continue to operate at lower voltages up to a point. I built a power supply using a 240V AC to 3.3V DC module but the camera failed to power on.
So I measured the battery voltage when fully charged and again when depleted, it turns out that at full charge the battery sits at 4.3V and the camera shuts down when it reaches 3.7V, bugger!.
So a power supply around 4.3V would be ideal, but I could not find a module around this rating, the next one up I could find was 5V. As the camera will charge and run off of a USB connection which is 5V I guessed this would be fine. So here is the final power supply.



Along with a fly lead to connect the dummy battery to the power supply, I checked that I was seeing the correct voltage, and checking that I hadn't screwed up the polarity before trying it on the camera!



All looks OK, so final test, the dummy battery in the camera and all seems to be working. Whoopee!




That's probably the most challenging part of the project out of the way. Left to do is

1. Knock up a set-up to mount the fish tank and camera.
2. Sort out lighting.
3. Add a mains socket in my loft as this is where I intend to place it when finished.

 

[bass_junkie83]

This morning I have completed the set-up, with everything mounted to a single sheet of plywood so that there is no chance of the camera position moving.

I have only part filled the tank with soil and set the camera height so that the top of the soil is at mid-height in the frame. The hope is that by doing this instead of completely filling the tank to the brim I will avoid seeing the top edge of the glass.



Just need to clear up my pig sty of a loft and make some room to put this and I will be able to get started .

 

[bass_junkie83]

I cleared a space in the loft this morning where it can be left undisturbed.



All that is left to do now is to sort out lighting.
My first thought was to get a cheap external flash unit, but as the Olympus has no hot shoe the only way I could trigger it is with an optical trigger. But the little pop up flash that would trigger it will also create some horrible reflections off the glass. So as an alternative I am thinking to use a continuous LED light, there will be no motion that I need to freeze so this should be OK I think.

 

[4wd]

You will need to be wary of reflections of cables etc too by the look of it perhaps some dark cloth over anything lighter coloured.
A good choice of seed might be runner beans, if it goes smoothly you could continue as they grow rampantly looking for light and then something to climb on

 

[bass_junkie83]

You will need to be wary of reflections of cables etc too by the look of it perhaps some dark cloth over anything lighter coloured.
A good choice of seed might be runner beans, if it goes smoothly you could continue as they grow rampantly looking for light and then something to climb on

Good point on the reflections. I have some black fabric somewhere which I can use to cover things up if needed.

I thought to start with some sort of brassica first, the seeds are small and might not show much but they are quick to germinate and will give me some quick feedback on anything that might need to be tweaked.

Then as you say a bean of some sort, so there is a nice big seed to see sprouting. And them maybe some carrots for a bit of excitement, which reading back is possibly the lamest thing I have ever said.

 

[Nod]

If the first attempt is a success, maybe a small selection of seeds - a couple of each of those you've mentioned would do. Maybe radishes as the brassica element - larger seeds than many Brassicas and pale in colour.

Good luck.

 

[bass_junkie83]

If the first attempt is a success, maybe a small selection of seeds - a couple of each of those you've mentioned would do. Maybe radishes as the brassica element - larger seeds than many Brassicas and pale in colour.

Good luck.

Good idea, a comparison of different plants growing next to each other could be good.

Lighting is now sorted by way of a cheap LED strip, angled to that there are no unwanted reflections. I am going with one shot every 30 minutes for the first go.

 

[bass_junkie83]

So I have completed the first attempt and learnt a lot to put into the next go.

In no particular order...

1. Do a better job of cleaning the glass! The glass between the seed and the camera is very clean, but smudges and smears on the back pane are still visible.
2. Moisten the spoil before starting to avoid a dark wet patch.
3. Take more care when covering the seed, it ended up moving away from the glass though this should be less of an issue with larger seeds.
4. My lighting isn't up to the job, more on this below.

I have been using a cheap LED strip light that I had knocking around which has been perfectly acceptable for the lighting I need, but is not good enough for the plant to grow under. The seed sprouted but got very leggy and didn't develop any leaves past the seed leaves (or cotyledons as I have just learn't is the proper name), so what I need is a full spectrum grow light which raises some other questions.

Grow lights, at least the cheap ones that I am willing to pay out for, come with built in timers which allow them to be on for up to 12 hours per day. Reading into it it seems having plants under light 24/7 is not good for their growth. I don't know if for a short period, i.e. just catching the initial sprouting and first couple of sets of leaves it would be OK. So one option is to get one of these light and remove the timer.

If I keep the grow light timed then I am not sure how to turn that into a good consistently lit time-laps, maybe delete the 12hr worth of dark frames and hope there has been no growth in that time?


There is just one more little problem to solve. The camera was shooting for 5 days, yet only recorded 18 shouts on the first day and stopped. The intervalometer was still triggering but the camera stopped recording images, I need to look into why as that kinda kills the project.