Why does my Extreme III 4GB only show 1.8GB?

Very common overlooked problem.? Solution:
Look on the back…See the three labelled switch positions?

Move the switch on the side to the one labelled 4GB.

Which Flash Diffuser do you like best? (Hot S...

Here are some results from the Photography-on-the.net crew: click

Much of it is preference and how much room you have in your bag. Remember the bigger the light source the softer the light. Omnibounce units can only do so much, since they are limited to low, white ceilings.

Stofen Omnibounce and Vivitar 285HV Side by Side

Updates:

Stofen Omni Bounce Pros and Cons
For those who are adamant about getting a Stofen Omni Bounce should know the pros and cons:

The advantages:
-Custom fit to your flash - no velcro, no tapes, no gunk on your flashgun if you’re trying to sell it at a later date.
-Small, lightweight - you can leave it fitted to the flash when it’s sat in your bag, and have it ready for action as soon as the flash has charged up - no messing around assembling something more bulky
-Simple, effective - just pushes on and then it works.

Disadvantages:
-Custom fit: means you’ll need to buy another if you change flashgun
-Small: may not be as effective as some larger diffusers on the market
-Simple: No real flexibility beyond the angle at which you choose to bounce the flash.

Gary Fong Lightsphere Vs. Stofen Omni Bounce
posted by Nikonguy2 on Dpreview:
The Stofen and Lightsphere are but two of the many diffuser reflector adapters that are available. Both work well in limited situations. The Stofen gives good results when you have the proper surface to bounce it from but works poorly as a direct flash type diffuser. The LS works wonderfully for very close portraits and poorly in other situations as Lawrence states. My personal opinion is that the original LS that has been discontinued works better than the new ones. The Ls is not the end all product it is advertised as being and most of the samples shown on the web site appear to be high ISO and large aperture shots using more ambient light than flash.

Where can I learn everything about EOS Flash ...

A common answer on most message boards:

http://photonotes.org/articles/eos-flash/

ttp://photography-on-the.net/forum/showthread.php?t=46599

Those two links should cover just about every EOS flash topic.? Happy Reading.

Does anyone know how to calculate how far a f...

Sunny 16 is an approximation for ambient light exposure and is
unrelated to flash coverage. Flash coverage/distance is not affected by
levels of ambient lighting, only distance(inverse square law) and flash
Guide Number(power).

Distance = GN / f stop at ISO 100

at ISO 200 multiply by 1.4

at ISO 400 multiply by 2

So on a sunny day, the max distance of a 550EX, using f/16, is about 4 Meters at ISO 100.

Flash fill indicates that you are using ambient light as your
primary light source and flash to just fill in some shadows under the
eyes, etc. That means you should also be dialing in -FEC to the tune of
-1 to -1 and 2/3 as long as you stay within that max distance. Outside
that distance the flash will be maxing out and may give erratic
results.

Ron

Can I build my own flash battery pack?

Sure can.? Its cheap and relatively easy to do!? http://forums.dpreview.com/forums/read.asp?forum=1027&message=6038636

Ivan

What is flash trigger voltage and why should ...

The flash trigger voltage is the internal voltage used inside the strobe/flash to trigger it’s circuit. To activate a flash the circuit needs to be closed (turned on) and the flash trigger voltage needs to flow thru the switch. Simple right? Yes, but what is usually the trigger? Well your camera is. Hot shoe or pc sync are built in switches of the camera that close the circuit when the shutter button is pressed.

So what? Well, most newer digital SLR cameras have a limit to how much voltage it can switch. Hence, there is usually a “safe” pc-sync or flash sync voltage that the camera must not exceed. Some flashes with a trigger voltage of say 250V is not intended to work with your Digital SLR with a sync voltage designated at 6V. This is important to know since most early model flash units had high trigger voltages.

I highly recommend you check out the “Photo Strobe Trigger Voltages” Website to see if your flash and camera are compatible before starting a fire Maybe not so bad, but you get the point.

PS. If you have a newer SLR and are thinking about the Vivitar flashes get the 285HV. This has a low triggering voltage and will work with most modern SLRs. The original Vivitar 285 will do some damage!

Where can I find the trigger voltage of my st...

Here is the site you need to go to: http://www.botzilla.com/photo/strobeVolts.html

What is the best rechargeable AA battery?

The Battery Shootout:

http://www.imaging-resource.com/ACCS/BATTS/BATTS.HTM

What is fill flash?

Fill flash is often used when the subject of a photograph is in front
of a bright background, or a background with details that would
normally be lost with a standard flash mode.

Fill flash is a general term; it can mean different things to
different people, but almost always shares the common idea that it
simply bumps up the light values on the subject just enough to expose
the subject properly, without under exposing the background.

There are MANY ways that photographers achieve this. One thing to
remember is that your overall exposure should remain the same or very
close to the naturally occuring light. Your flash exposure should be
slightly lower than the ambient light (naturally occuring light). This
adds just a little bit of flash that only the trained eye can see
therefore making the photo better balanced with light and just
generally more dynamic.
dslro

How do I do the Overlay / Sequence Shots in P...

1. Open that image in photoshop.

2. Open the second image, go select all, copy the photo

3. Switch back to the original image, (control-shift-tab), and paste the 2nd photo on top of the first

4. Select all again, and then go to layer, layer mask, reveal all.

5. Set your color selections to black on top, and white on bottom. How
this process works is that using the paint brush with black as the
color ‘reveals’ what is under the top layer (use to reveal you in the
original frame), while white "paints in" the top layer more. Use the
white tool if you accidentally reveal the bottom layer over your 2nd
image.
Tazo

Is there a way to trick the AI Servo?

Tricking AI servo, three ways I know… (works in ANY mode):

1. Achieve focus lock on a subject and then whilst keeping the shutter half depressed and the subject centered, move the lens focus ring - camera drops into AI servo and will stay there as long as the shutter is kept half depressed. (Only works with lenses that support full time manual focusing such as Canon USM and Sigma HSM lenses)

2. Achieve focus lock on a subject and whilst keeping the shutter half depressed use the lens zoom mechanism to zoom in slightly. Camera drops into AI servo and will stay there as long as the shutter is kept half depressed. Obviously only works with zoom lenses and doesn’t work with parfocal lenses.

3. Achieve focus lock on a relatively close subject and then whilst keeping the subject centered, and the shutter button half depressed take a step forward. Camera drops into AI servo and will stay there as long as the shutter is kept half depressed.

All three methods take a little practice and some methods work better with some lenses than others. Fairly easy to do though.Rick

How do I calculate the Depth of Field?

Use a DOF calculator: http://www.dofmaster.com/

In most cases your lens will come with a DOF chart that you can refer to.

What is the crop / maganification factor?

Here is everything you need to learn about it:
Write-up at Luminous Landscape

Ivan

How should I sharpen my pictures?

Well, if I can give you one bit of advice, it’s that you should never use the ‘Sharpen filter’

It’s not controllable and isn’t generally ’smart’ on what it sharpens.

Learning how to build edge masks is not that difficult, but takes a lot
of explaining so you’re better to read something like this:

http://www.luminous-landscape.com/tutorials/smart_sharp.shtml

And this is an excellent overview of sharpening to
web/prints/whatever which serves as a good starting point in developing
your own tailored sharpening workflow:

http://www.creativepro.com/story/feature/20357.html

Leeroy

How do I perform a lens focus test?

Focus Test Links:

http://md.co.za/d70/chart.html

http://www.photo.net/learn/focustest/

Ivan

How many actuations is my camera good for?

Curious how long your camera is going to last.? Here is a rough estimate based on actuations:

300d - 350d? ~ 30,000+

20d ~ 50,000+

1d Mk2 ~ 250,000

Ivan

Where can I find a manual for the 20D?

http://consumer.usa.canon.com/ir/controller?act=SupportDetailAct&fcategoryid=215&modelid=10464

Click on "Product / Software Manuals", then download in whatever language you want.

Comparison of the Digital Rebel XT vs. Modif...

A very interesting side by side comparison of the 350D/XT and a modified 300D:

http://www.camerahacker.com/Canon/DRebel_Comparison.shtml

Is there an alternative to the $120 white tri...

If you own a Canon 70-200mm f/4L, 300mm f/4L or 400mm f/5.6L
lens, you don’t have to spend $120 for the white tripod ring (Canon
Part: # 2889A002, "Canon Tripod Mount Ring A"). Instead, buy the black
version (Canon Part #: 2888A002, "Tripod Mounting Ring A for 200mm f/2.8L II").
This part is identical to the white version (targeted at L lenses) but
is painted black. Though not as asthetically pleasing, you do save $35!
Matt

How do you clear your CF card on Canon DSLR?

The quickest and most used way according to forum users is to "format" the card in camera.??
Ivan