Limited to 1/30 sec using pop-up flash on K20D?

<p>I want to catch the grandkids doing something cute. I don't have time to fiddle with my big flash, setting to X (1/180th sec) setting and checking which aperture does the job.<br>

Trouble is, flipping up the built-in flash results in 1/30 sec, no matter whether I'm in AV, TV or Green mode. I find 1/30 sync to be OK in many situations, but not with fast moving kids. I don't find the manual to be much help. Or am I dumb?</p>

<p>The manual indicates that the flash will use any shutter speed 1/180th and slower in Av depending on ambient light. You should be able to change the shutter speed while in Tv or TAv. Some test shots with my K20D in Av mode the camera set itself at 1/45s. In Tv mode I can set the speed to any speed up to1/180s. I hope this helps.</p>

<p>it's probably because the camera's using idiotic logic of setting the speed to the (approximate) reciprocal of the focal length used, they did it back in the zx-blah film days as well; however, you should be able to overwrite it in M mode. You can test this by putting a zoom on and and zooming in and out, while observing the sync speed changing.</p>

<p>I love the way Zenit phrased that. Yes use M mode or Tv mode and set the shutter speed you need. But remember that you have very short working distances. Maybe less than 10 feet in very dark situations.</p>

<p>I've always wondered about this 1/180th sec. limit when using the flash on my K100D. Can you freeze motion with this limited shutter speed? I remember this specific limit has something to do with the speed of the firing of the flash syncing with shutter speed. Is this correct? </p>

<p>I have yet to find an override on my camera in allowing the use of a faster shutter speed to freeze motion.</p>

<p>Or does the fact you can attenuate the flash output makes this 1/180th limit not much of a concern?</p>

<p> </p>

<p>As to how much shutter speed is needed to stop motion- depends on how fast the motion! 1/180 sec is generally enough to freeze most action, other than very fast action. If the ambient light conditions are on the dark side, the flash itself, providing MOST of the light for exposure, even at 1/30 sec or certainly at 1/60 sec, will generally stop motion. </p>

<p>Where flash is used for fill under brightly-lit conditions, its influence is not adequate to stop motion on its own, so shutter speed must be increased as it would be without flash. If I meter a scene and find exposure to be down only a stop or two, then it is clear that the needed flash will be as fill, and the ambient light will provide the greater lighting of the scene for exposure. Here is one such example of fill flash use under brighter conditions. Note that the 1/125 sec used for the shot, with flash, was not sufficient to freeze all motion- the top wrestler's leg is blurred as it moves. But this is why I chose this shutter speed, so that such fast motion of limbs <em>would </em>be blurred, to convey action. If conditions would have been dark, with the flash providing most of the lighting, this motion would have been stopped as well.</p><div></div>

<p>To answer your question more specifically, Doug, when in Program or in the Green mode, the camera will choose a shutter speed for flash based on the focal length used. A higher SS for tele and less for wide. It goes to a lower-end safer value for the FL to presrve a modicum of hand-held safeness for when flash is used as fill, but also provide adequate effective flash distance. It also measures the available light and will balance output and shutter speed accordingly so the surrounding areas that are not lit by flash are still visible. If you go outdoors in daylight, the fill flash will kick in at a higher shutter speed to balance exposure with the outdoor scene. But as with all automated functions, your needs are not always met. And your camera, being the type it is, is equipped for you to do it your way. When action is involved, with or without flash, the Tv mode or Manual mode will allow you to control your shutter speed.</p>

<p>t lookingbill-with a focal plane shutter(which the dslr has) max shuuter speed with flash is the sspeed that you get when the first edge of the shutter reaches the far side of the frame, BUT the trailing edge has not yet started across. if you attempt ot go faster the the trailing edge will have already started across and a strip under the trailing edge will not get the flashes light. you can go slower than xsync but not faster.</p>

<p>also note the following, in any situation/scene in which the flash is the primary light source. it is the flash's duration that stops motion NOT THE SHUTTER SPEED. the flash duration can be as fast as 1/50000sec depending on the flash. this is how you see bullets stopped in flight. they are stopping motion with the flash not the shutter speed. another scene is the fired arrow going through a egg with half the arrow one side and the other half on the other side of the egg. this is done with flash speed.</p>

<p>if you inside a home or a building in dimish conditions, then the flash is the primary light source. simply set the dslr you are using to the way flashes are used and you will stop any motion in the scene. for example, you do not see any motion in a wedding ceremony or reception. the flash stops it all.</p>

<p>for normal ext flash operation, not fill or highspeed, simply mount your pentax 360 or 540 flash to the dslr(this works for the istD, k210,k20. do not know about the k7) turn on dslr first, set sspeed to xsync, turn on flash, set flash to pttl, set fstop to be used(i use f8.0. this makes the whole thing full auto to 39ft without bounce flash, if bounce about 25ft or so. this is for the 540), all flash settings to default, frame your scene and shoot. i use this for all my flash shot and the exposure is fine. this was the method i got from pentax boulder colorado when i called them on the phone. if you wish to use a flsh defuser, like the stofen omnibounce do so. but the range is not what the flash says on the back, it is about half or 2/3. still, with the described rig above the makes diffused flash full auto to about 20-22ft.</p>

<p>There it is. I use the DA 21 for group shots inside in small rooms. I also got pretty good results with a Canon hot shoe flash (low voltage trigger) in the shoe, with TV set to 180. Rather than set the distance and f-stop according to the scale on the flash, I just took a couple of test shots to find the best aperture.<br>

I have found the pop-up flash to work well for fill flash situations outdoors.</p>

<p>One other important tip- when dealing with darker conditions and/or action, it is best to increase ISO, which will also increase the flash's effective distance, and allow higher shutter speed if needed. My above shot was using Fuji Superia Xtra ISO 800 film.</p>