DIY Softbox grid / egg-crate
I have a couple of long + tall softboxes, what I guess you could call strip softboxes.
A cheap one that keeps breaking but came with lots of additions such as a grid/egg-crate and a nice one from Interfit (SLBR412 – 120cm x 40cm) that didn’t. I initially bought the big Interfit strip to use as a main light – for even whole body lighting – but on occasion and more recently I’ve been using it as a rim-light. However due to it’s size (particularly 40cm width) the spill from it is quite significant. So I started looking for a grid for it.
The task was not very easy. I even e-mailed Interfit and they couldn’t suggest anything. Having looked around I seem to remember (it was a while ago now) finding a custom maker that would make it for about £150 from the states – more than the cost of the actual softbox! (about £100). 120×40 cm was a tricky size too as other manufacturer strips seem to be about 120×30 cm.
So I decided I’d try to make my own, how hard can it be ;)
I found a few online examples of making DIY softbox grids and took some inspiration from those (See References below).
Since I had a pre-existing one I thought I might as well replicate that ones as it seems to work fairly well.
Material wise – it was made out of some form of thin but stiff material/webbing. Since I have no idea about material really, or more so about something unusual like this I just went into a haberdashers and asked what they had was black and fairly stiff. Just happens I was in John Lewis looking for something else (think blackout material) so asked them. They directed me towards “Bolton Twill” saying that another photographer had used some recently! In fact they’d taken almost the last of it so I had to order in. Bit foolish of me really as I hadn’t done any measurements at that point.
Dimensions wise I kept with the existing squares dimensions 6.5cm x 6.5cm and also the same depth – approx 4cm as this softbox has an extending edge from the diffuser panel – as per the cheap one.
I followed the design pattern used by Adriel Henderson give or take a few minor changes. I cut a couple of lengths that were long enough for a side and and a top/bottom – so 120cm + 40cm = 160cm, which would server as the outside edge. For the boxes followed this plan (see diagram). This is the view as seen if looking directly at the softbox. These strips of fabric would also be approx 4cm deep.
The Blue points = the contact points where you join them. (I’ve only displayed for the first strip)
The Red areas = As per Adriel’s design – there is a bit of doubling up where a length of the strip will cover an existing portion of fabric.
I did find an alternative design (sorry I can’t find the link to reference now) which would do away with this doubling up BUT:
- It would mean marking out and cutting a fair few more strips.
- The strips would be of varying lengths – so more work/time consuming
- I had enough fabric to not worry about this doubling.
All materials/equipment used:
- Material – Bolton Twill ~ 3m – £27
- Fabric Scissors ~ £7
- Hand held sewing machine – £4
- Thread £1
- Bobbin – £0.60
- Stick-on Velcro (hooks) ~4m – £6
- Fabric glue – £3
- Chalk to mark out lines – already had.
I had considered buying a mini proper sewing machine – you can get them for £20-40 but rejected it as it would take up space later, and I thought the above would be more suitable as I could sew up into the grid holes, while a larger machine would have issue with sewing parts already stuck to existing small holes – the holes wouldn’t be able to fit…. but I was mistaken – more on that later.
Although 6.5cm squares don’t fit into 120cm evenly – I thought I should round up to the whole square as it’s not a bad thing having a grid slightly too large – better than one that’s too small.
So for the outside edges I needed to cut 2 strips of 124+39 + 2cm spare = 165cm (+ spare if there was)
For the vertical zig-zag sections I had to cut 6 strips of 241cm + spare – so roughly 245cm (+more spare if there was)
One definate tip is while you mark out the strips of fabric – also mark out the markers for where you will join them together – so every 6.5 cm for me. This makes it a lot easier to mark them at the same time – no need for duplicating work – and means you’re sure your glueing/sewing the right place.Thought I had a picture of this – obviously not.
Initially I was going to glue the strips in place but glad I went with sewing as it was sturdier.
I thought that the little hand sewing machine would be able to sew into the squares as I consructed them – but turns out it has one of those fabric advancing feet as standard sewing machines and it moved across – so I had to sew sideways into the squares.
I would initially sew the squares together – but as the little machine would miss some stitches I’d sew one way and then another – I could turn the machine around with some wrestling.
Since the stitch the machine makes can easily pull out along it’s length – the ends do need to be fastened. Rather than sewing this into the fabric by hand I took the easy route – I glued the blighter’s on ;)
Shame I didn’t take more photos explaining the production really… but I guess the layout is fairly basic.
After finishing the grid I trimmed off the fraying edges and put a little spot of glue at all the intersections to try to stop any more fraying.
Attaching to softbox
My existing grid uses stitched on velcro (hook side) to attach to the rim of the softbox which is lined with the opposite hoop side velcro. As my large softbox has this too – I thought migt as well do something similar.
Rather than sew-on (I don’t think the littlsewing machine could cope with it) I’ve gone for srick-on.
Velcro strip usually start from about 20mm but I thought I’d go for slightly wider 25mm to give more support and even out the weight.
Strip pointing at white seamless without and then with the grid:
Here’s a view from what I’d roughly say was 45 degrees. The exposure was as the above two shots – no post done to the levels etc.
You can see there’s more light bleed coming from the first column of cells. InitiallyI wasn’t sure why this was – although not exact – my cells were of roughly similar sizes. But I think I’ve figured it out – because the softbox is a wedge shaped – i.e. narrow at the back where the light is, and wide at the front – the side of the softbox the grid is attaching to isn’t perpendicular if looking head on of course – it’s flared. And so the first column/row on both sides and top/bottom will be wider and have a slanted edge.
There are a few things I would have done to improve the grid….
Although it does a good job – I think I could have looked around a bit more – that of the existing grid is softer and lighter.
I was initially tempted to buy a mini-big sewing machine – but rejected it thinking it wouldn’t be able to sew the squares together as they are only 6.5cm square, and the base of the machine would not fit through there. I also thought the little machine would would sew into the squares, making it easy, but due to the fabric advancing feet I had to sew sideways into the squares.
To do this I flattened the edges of the squares and this made me realise I could have just dones this with a standard machine!
The little sewing machine was also rather temperamental about making stiches – sometimes the back hook wouldn’t catch – so I doubled up.
The velcro attaching the grid to the softbox does come away a little – even though the stick does seem very firm. Looks like I’ll need to sew it a little. Maybe just at regular points rather than al along.
Size of grid cells
Although it does the job – in reality I would prefer that the grid restrict the light more – especially at the edges where I discovered an issue. To do this I would have needed to do one of two things – either make the grid deeper (unlikely as there was no more space to velcro it in and the fabric isn’t THAT firm) or make the squares smaller.
Of course making the squares smaller would mean more sewing and more strips.
While looking up the references to write this blog I came across an old DPreview forum thread I’d started when looking for a grid last year. I’d forgotten someone had linked to a page detailing technical measurements/sizing for grid cells for the angle of light.
A 30 or 20 degree grid would have been great, but with 2-3cm squares that would have meant double the amount of sewing. With this little machine – not a task I’d fancy.
Maybe I’ll consider making another with smaller square – but as I’ve not even used this one properly yet – I’ll stick with it for now. Should probably use my time to do other things…… like writing this blog ;)
Material – used their pattern/design
Gaffer tape didn’t really use