Flash Diffusers... No need to spend big $$$

This blog is in the process of being moved. Please read and link the updated version of this post here... http://www.australianlight.com.au/blog/post/flash_diffusers_no_need_to_spend_big_dollars/

---------------------------------------------------------------------------------

I see many forum threads extolling the virtues of the latest and greatest camera flash diffuser, wiz-bang light modifier or best ever bounce attachment.... the "must have gadget that makes your on camera flash produce studio lighting".... etc etc

Well the fact is.... physics has not changed! Light still travels in straight lines, is diffused and bounced just like it always has been, sees it's intensity drop to 1/4 as the distance doubles and can only be made "soft" in ONE way..... by making it BIGGER in relation to the size of the subject lit.

This is the principal behind both bouncing and diffusing our flash units. Bounce the flash off a ceiling or umbrella and the light source becomes much bigger. Diffuse our light source through a much larger attachment like a light box and it becomes much bigger.

Of course size is relative to distance... ie: a 100cm soft box will give lovely soft light when 50cm from your subject, but put it a 5m and it starts to become "relatively" small to the subject and the resulting light will be much harder.

What about on-camera diffusers that are not much bigger, how well do they work?

Basically these "diffusers" would be better off called "bounce" attachments, as the relatively small increase in physical size does little to provide a softer light. Instead, they spread the light in all directions, so that it can bounce back off walls and ceilings etc.

Naturally a percentage of this diffused light makes direct contact with the subject and it is the combination of this direct light (which is strongest because it took the shortest route) and the weaker bounced (or "fill") light that makes for a more pleasing light with no harsh shadows.

How do these diffusers work outside, or in large open rooms with nothing to bounce off of?

The short answer is.... not very well. As I stated earlier, the relatively small increase in physical size does little to provide a softer light and if there is nothing to bounce off there will be no secondary "fill". So in effect these diffusers make things worse in these situations, as they waste light that could otherwise be used to light the subject.

I have seen demonstrations where one flash attachment is used to fill a whole ball room of people!

Yes I have seen those too, but don't be fooled by what information is conveniently left out. In the demonstrations that I have seen, the photographer avoids mention that a much wider aperture or higher ISO has been used. When this is done the pre-existing ambient lighting becomes a very large player in the exposure. So the result is NOT as much about how good the attachment is, but equally (if not more) about the different photographic technique used. In the case of a wider aperture, the result comes at the loss of DOF (depth of field) and this is not desirable when trying to keep large number of people in focus.

So what is the best flash diffuser that covers all applications?

None! All the diffusers work given the right situation (normally enclosed spaces), but no "one" is the best at everything. It is my advise to have a number of techniques in your bag of skills and apply the best one for any given situation.
------------------

Here are a few guides to remember when you search for your new flash diffuser....

1: Diffusers are LARGE (ie soft boxes and umbrellas) and need to be set close to your subject to maintain relative size.

2: Most "On camera" diffusers are really "bounce" attachments and have little to no direct diffusion effect, but rely on the diffused spread of light to bounce back off nearby objects. (There are some units that look like little soft boxes and are used as direct flashes.... these are still too small for great diffusion effect in most situations like portraits, but are very good for tiny subjects like macro, where "relative to the subject" they are actually large.)

3: There are many diffusers available on the market today and regardless of the price and makers claims, you can achieve the very same results using everyday items as simple as a business card, tracing paper or even your hand.

4: All diffusers require an understanding of both flash & ambient exposure and how these can be combined for effective results.

5: When testing diffusers always use the cameras fastest shutter speed for flash sync and at least f8 or f11 at 100ISO. This will ensure that ambient light plays little part in the result and you will get a true indication of the diffusers ability.

6: Don't be baffled by the makers BS! They have an agenda to sell you something... normally a 5 cent bit of plastic at $50-100

The following image is to give you some idea of the results from various techniques..

Full Size Image

This is my "home made" diffuser.... a 40 cent sheet of tracing paper makes about 6 and the results are every bit as good as a popular $100 unit.

Cheers

Rusty
AustralianLight - Landscape Photography

UPDATE: As mentioned previously mentioned... Without an object to bounce off, any and all small on-camera flash diffusers are useless. So in this outdoor situation, the flash was fired through a 36 inch translucent umbrella. (See more information in the comments below)



Tags: diy flash diffuser home made stofen bounce flash light modifier photography photographic camera speedlight

Rusty's Ramble #6: PLEASE, Enough bad HDR!

Arrrrgh! I am so over the bad use of HDR.

HDR stands for "High Dynamic Range" and is a method of combining multiple "different" exposures into one image. The aim of this is to provide a more even exposure across the image... eg: no "extremely" dark shadows that display no detail, no "completely" blown highlights that display no detail and a smooth transition of colour & tonal values in between.

HDR does NOT stand for "Highly Distorted Rubbish".... sadly though, it seems that this is a very common outcome for many HDR users. These HDR images are everywhere at the moment and they keep appearing. You know the ones (naturally I can't single out anyone, or I would be mud) they look like fluro cartoons, just go to any online gallery and search for HDR and you find them.... Lots of them! :-(

The Golden Rule of HDR #1:

Good HDR will not even look like good HDR.

The Golden Rule of HDR #2:

If your image looks like HDR, refer to Rule #1.

"What?" I hear you say. "Good HDR will not even look like good HDR??? - Does that even make sense?"

Yep it sure does. Good HDR will simply look like a well exposed image. It will contain tones that carry right through the dynamic range of the image and these tones will INCLUDE shadows and highlights!

That's right, shadows and highlights!!! They are meant to be there. Take a look around.... where ever you are... right now... take a look. The chances are that you will see shadows that are pretty dark for your eyes and you can only just detect real detail. Similarly, you will probably see highlights that are very bright and you can only just see detail.

This is NATURAL!! This is how we see things in the real world. So why the heck do we end up with HDR images with none of this? How can a user sit in front of their pooter and look at a plastic-fluro-cartoonie image, with no shadows and no highlights and think it looks anything but WRONG??

Yeah I know.... many times someone may want to create an "effect". That's OK, I have no problem with that, as "art photography" has it's place. Just don't try and pass it off as good HDR.

"Keep it real Homie" - HDR Photography 101

End of ramble. ;-)

Cheers

Rusty

Rusty's Ramble #5: 24mm... My forgotten focal length no more!

 

Anyone who has visited my on-line gallery will see that I shoot a lot of wide landscapes. I use a 1DsII (full-frame sensor) and 17-40 f4 L lens that may as well be glued at 17mm. (Note: 17mm on a full-frame sensor is about equal to using 10-11mm on an smaller APS-C sensor camera like a 40D)

17mm gives a very wide FOV (field of view) which is great, but this often comes at the cost or corner sharpness and wide field distortion at the extremities. I use techniques to minimise the effects of these, such as vertical composition, close foreground objects and hyperfocal focusing to maximise the DOF (depth of field). But get these even slightly wrong, as you will pay the price of soft corners and/or unnatural looking distortion.

Naturally some lenses are better than others, but in general, ALL ultra-wide lenses have these issues to some extent. The Holy Grail for me, has for some time now, been an ultra-wide lens with sharp corners and no distortion..... sadly, my quest continues. 

I should say that my 17-40 is mighty fine lens, as is Nikons latest ultra-wide zoom, but even with the better examples of these lenses offering sharp corners at short focal lengths, the wide-field distortion is pretty much inherent in the FOV. :-( (Note the 17mm image above and how the rocks seem to rush away in the bottom left corner)

Recently I was revisiting my wide landscape work and preparing to once again ramp up my quest for the Holy Grail, when my brain finally kicked into gear..... "Why shoot 17mm all the time anyway?"

.....Der!!!! It was a boom-shanka moment for my tiny pea brain and I reached into my bag for my Olympus 24mm.

I regularly use my Oly 24, but always reserved it for stitched panoramas. When used in vertical/portrait orientation, the 24mm FOV provides just the right amount of image for a single row pano and it's exceptionally sharp, minimal distortion characteristics made it perfect for stitching multiple images. Hmmmm? "exceptionally sharp, minimal distortion characteristics".... der! I should have been shooting some of my regular landscape work with this lens much sooner.

So into my bag went the 17-40 and there it stayed while I gave the Oly 24 a solid run for the weekend. Well the results speak for themselves, sharp contrasty images from corner to corner and no unnatural looking distortion. (as shown)

So why have I done everything at 17mm until now? To be honest I don't really know. In my film days my widest was a Canon EF24/2.8 and back then I always considered it wide enough. After getting the 17-40 for my digital, the ultra-wide FOV became a bit of a novelty that soon turned into standard practice.. I guess I simply got "stuck in a rut" so to speak.

So this begs the question.... is 24mm the new "novelty" for me at the moment? ....I don't think so. I am a bit of a pixel-peeper and image quality is an obsession of mine, so I don't see how sharp corners and no distortion can ever be anything other than "getting it right".

I will still shoot with the 17-40, but it will be no longer automatic to grab it for anything landscape. If the subject matter really needs 17mm (and wide-field distortion and corner softness can be kept to a minimum), then the 17-40 will get a run, but even so.... if that same image can be created equally effectively at 24mm, then image quality will most likely be my deciding factor and it will be the Olympus that I reach for.

I guess all this means that we should be careful not to get set in our ways (as I was).  Every image is new and deserves our attention to every detail, rather than us simply "shooting how we normally shoot".

Cheers

Russell
My Gallery: http://www.pixelpix.com.au/gallery
Australian Digital Photo Of The Day: http://www.potd.com.au


Photography help for beginners - Film & Digital Camera Techniques - Post Processing - Photography tips and tricks - 24mm Olympus - Landscape Photography

Tip 9: Waders - The best $50 a landscape photographer can spend!

Well it's been quite a while since I have made a post to my blog.... very slack of me I know :( but I am here to rectify that, even if it's only with a small tip.

Waders! ....Yep, those dorky looking rubber fishing type waders.

I purchased a set recently for a trip down to Bright in Victoria. Knowing that the area has mountain streams, I figured that waders might allow me to get into some more "unique" positions, as I would not be limited by my aversion to cold, wet water.

As it turns out, my Waders are the best $50 that I have ever spent as a landscape photographer. (My Grizzly Bear repellent may well turn out to be the best, but until I go back to Canada that remains to be seen. ....thinking about though, how will I know if it's working? If I don't see a grizzly, is it my repellent, or are there no grizzlies there to begin with? Hmmmm??) Anyway, back to my waders....

Being able to wander over river rocks without the a real worry about dry foot placement was really quite freeing and being able to sit or stand in cold mountain water provided some excellent POVs. (POV = Point Of View)

Amazingly, the waders keep you warm too! I could feel that I was standing in cold water, but at no time did I feel cold. I look forward to using these in the warmer swampy areas, as my aversion to snakes and all things creepy-crawly is just as strong as my aversion to cold, wet water. ;-)


This image gives you an idea of how useful waders can be, especially compared to your regular gumboot.


The following image is an example of the unique POV (middle of the rock pool) that the waders allowed for in this pano.

As usual, larger versions of these can be seen by clicking the images, plus they can also be found in my gallery.

















Cheers

Russell
My Gallery: http://www.pixelpix.com.au/gallery
Australian Digital Photo Of The Day: http://www.potd.com.au



Photography help for beginners - Film & Digital Camera Techniques - Post Processing - Photography tips and tricks - Waders for landscape photography