Tagged: off

12th October 2017 – Steve Dyer My Photography & Building An Off Camera Flash Set Up

This week we had our first of the season’s My Photography sessions, Steve Dyer taking us through his studio work including lights, modifiers and some of his post-production work flow. Some fine images, and a sound outline of the equipment he uses to get his preferred evening was an illustration of some of the talent we have in the club. And Steve was happy to state that the club has played, and continues to do so, a strong part in his development as a photographer.

 

We have looked at light modifiers in the last two posts of 2016, dividing them into soft light modifiers and hard light modifiers. We also referenced the excellent The Strobist website and it remains well worth the effort. These three will form the underpinning of the rest of this post, which will mainly, but not exclusively, be about building an off camera flash on a budget.

 

Steve has spent the last few years and not a little income in collecting his equipment he uses in his set up. The modifiers can be gained quite cheaply, but the build quality is what you really pay for when you buy the more established branded modifiers. One of the keys here is how core these pieces of equipment are to our particular form of photography. Another is our available budget, of course. It can be done relatively cheaply and here we will be looking at the options from a restricted budget perspective.

 

So, our mission is to put together a useable off camera flash with modifiers. Keeping within the basic theme we will start with the flash unit.  Canon Speedlites start at around £160 and, obviously, are designed to work with Canon cameras (though will work with other makes but might have limited use of extended features) and we can pay over £500 for the top of the range and into four figures for the specialist designs. Nikon is not so very different. But how low can we go? The main thing that we give up on a restricted budget is power, as expressed by the Guide Number.

 

The Guide Number (GN) is far more than this though. Usually expressed in meters (feet in the USA) the GN is a tool for calculating the light falling on the subject from that unit at a given distance or F-Stop. How does that work? Actually quite simple. I have a flash gun with a GN of 33. I am 2 meters away from my model. The GN = f Number x Distance. The industry standard is 100 ISO but check the flash-gun’s handbook.

So, back to school maths, GN 33 = f number x 2meters.

Therefore 33 / 2 = f number or 16.5. Set the aperture at f16 to f18 according to the capacity of the lens diaphragm.

 

In an ideal world going to 200 ISO effectively doubles the guide number. Well it would if it weren’t for the laws of physics. There is a thing known as the inverse square law. Double the distance means

four times the light to get the same degree of illumination on a subject. So ISO 400 to get twice the light on the subject from a 100 ISO base.

 

Now TTL metering will sort all this out if the flash unit and the camera are capable of dealing with it, but that basically doubles the cost of the manual flash.  Or we could buy a flash meter (make sure it is a flash meter not just a light meter, and better it is calibrated for photography. as we may waste our money) to do accurate calculations for us. However, dedicated off camera flash meters start at around £175.00. Not within our remit here. This is one area where chimping comes in and getting to know your equipment will really pay off. We can, with practice, get pretty close to right first time but, with the cost per frame and immediacy of digital, test frames consume not a lot other than a little time.

 

As we are talking off camera flash we will need some way of triggering the flash off body. Basically there are three ways to do this: Fixed cable (if the flash unit will take that, but most modern ones will); light trigger; wireless trigger.

 

Wired isn’t much, if indeed any, cheaper at the budget end of the spectrum than wireless. Light triggers (Optical) are built into the front of flash units so enabled and are usually encased in a red plastic cover. These can be triggered by other flashed including on camera flash if you have one built in. Wireless triggers are very popular and even the cheaper ones function pretty well, though it is necessary to maintain a line of site to ensure the flash triggers. The cheaper ones will be more prone to misfire, and will have a limited number of channels they can operate over (usually 4). The more sophisticated units cost more money, are better with weaker signals, can be programmed to fire in zones or sequences, even so there are some good units out there for not a huge amount of money.

 

As an extra and when you have one, essential, piece of kit to complete this summary, a light stand is a good investment.  A light stand will take your flash to a higher angle, usually up to about 9 feet, or just under three meters. This gives us a lot more lighting options.

 

So how much can we do this for? * At 16th October 2017:

 

Flash Unit, Amazon Basics (made by Godox) £26.

Neewer Light Modifiers for Flash £46

This is a pretty complete set and a good start. Refer to the Soft and Hard Light modifier links above and note that some of these quality of light is determined by their size. This is a good place to start, but by no means the only place.

Wireless Triggers  £11

Light Stand £13.60 (two for £22 also available)

All in around £95.

Thanks Steve, for the entry point. The rest of us, enjoy.

 

*There are lights, stands and back drops that members can borrow from the club. See Eddie House.

8th December 2016 – ROC Round 2 2016/17 and Light Modifiers

Round 2 of the club competition last meeting and I shall link to the club website here where the winning entries will be posted in due course. Club thanks to our returning judge Roger Mallinson who got though 21 prints and 58 Digital entries in a prompt and informative fashion.

 

This week we are going to return to the studio as it were, and start to investigate light modifiers as previously promised. So, starting with the obvious, just what is a light modifier? Yeah, ok, it’s something that modifies light, a true but otherwise unenlightening answer which we need to look at in a little more detail. If we take the word modify we can use it in two senses:

  1. To change in form or character; alter.
  2. To make less extreme, severe, or strong.

With light the second meaning is a consequence of the first, it is also an inescapable  consequence and though a tad obvious to some the conclusion is the same as the one that Mark and Rob gave us a couple of weeks back, that if you are going to do a lot of this then it is best to buy yourself a light meter. The reasoning is thus, every time you make an adjustment in intensity or distance (one and the same thing often times) then you are going to effect the elements of the exposure triangle and using the old saying: two measures to one cut as a guide, okay two measures to one slick in this case, means a lot of time effort and battery can be spared. For the occasional user then it is a case of trial and error. Eventually you will get to know your kit well enough to be reasonably accurate in your estimations.

 

There are basically two kinds of light modifiers which we can divide into soft light and hard light. Flash is the most likely entry point for a hobbyist into controlled off camera lighting. With flash we tend to use more of the hard modifiers, that is we use them more of the time, but both categories need considering.

 

The thing to remember, that is the thing not to get carried away with, is we modify light to enhance the subject. It is always about the subject, he, she or it, not about the modifier. Unless you are writing about modifiers I suppose. Still, that false conundrum aside we choose the modifier to light the subject, not the subject to show off the mod as a general rule. The subject is the thing. Always.

 

Soft Modifiers

So this week we will start with soft modifiers. Another term for light diffuser, because diffused light gives soft shadows, that is the differences between light and dark look more a gentle grey than a stark black. Make no mistake we are using the light to create shadow. Shadow is the form of the statement we are making and without light there is no shadow.

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So a soft modifier spreads the available light over a larger surface, that is, larger than the source itself . Smoothing the transition from light to dark on your subject the main use of soft modifiers is for key lighting in portraiture. The key light is usually the primary light source, the brightest and most important.

 

The two most frequently used soft modifiers are softboxes and umbrellas. Softboxes are normally vaguely pyramidal and lined with a silver, highly reflective material. They come in a variety of sizes and those sizes relate to how soft the light is, not how wide spread the light is. Yes, you are right, those two things are directly related. Most softboxes and umbrellas are used at a distance of two meters or less from the subject. Though there will be differences in the areas lit between any two given sizes, at these sort of distances they are minimal and really, really not the point. The point is how diffuse the light is, how soft the shadows are.

 

Softboxes are a studio staple but they can be very bulky, heavy, require more than one stand and generally take up a lot of space even when not being used and can take quite a time to set up. They are good for using with other modifiers though and also good at controlling light spill (basically light coming through at unintended angles which may or may not intrude on your desired effect).

 

A subdivision of the softbox is known as an Octa, octabox, octadome or octa softbox/dome . Octas, as we will call them,  come either as an octagonal shaped softbox or as a hybrid softbox and umbrella. The angle and amount of light fall off is different to a softbox, but they do tend to be a lot more expensive and as bulky as softboxes.

 

There are further modifiers than can be fitted to a softbox or and octa. You can add grids (to give direction), flags (put shadows in), filters (control colour and intensity) to give you a greater control.

 

In case you are thinking, “Hey, I can make my own softbox” then I have to say, yes you can. The difference is in the quality control and the length of time that it is likely to last, but there is no reason why you can’t use tin foil and a cardboard box to put over your light source (flash gun rather than bare bulb, depending on the quality and exclusions of your house insurance and fire damage claims) and a plain shower curtain works wonders (make sure it doesn’t have  blue tinge if made of plastic and yes it will melt over a hot bulb). Go ask YouTube, there are many different videos covering this.

 

Umbrellas

Essentially umbrellas for modifying light as, opposed to keeping the rain off, come in two varieties: Shoot through and reflective. They are a little more untidy in the way that they deal with light, it will spill round the open edges. They are also prone to having a hot spot which may or may not prove a small problem. They are usually a lot cheaper than softboxes or Octas.

 

A shoot through acts like a lampshade, softening the light simply by putting a semi transparent material between light source and subject. A reflective umbrella is opaque, black on the outside with a highly reflective, usually silver, sometimes gold or maybe white interior. These are pointed at the subject so that the open side of the brolly is facing the subject and the flash unit faces the inside, away from the subject, to bounce light from all round the internal reflective surface from every attainable angle.

 

Umbrellas come in a range of sizes from small to huge (10 feet or more) and they are a low price, effective, portable light modifier. This makes them very popular. As already mentioned their biggest disadvantage is their tendency to spill light around the sides. Not a huge problem, normally, but one which does need to be attended to. Unlike softboxes there really aren’t any effective DIY options, but they can be bought pretty cheaply and so even if there was a DIY alternative the cost advantage would probably be very low.

 

Next week we will be looking at hard light modifiers and it is the club social, see website and or Facebook for details and Rob is doing a Bokeh session to boot.