Mistake by jumping to Canon ?

<p>I got 5 D MK II , a week back. The sync speed of 1/200 is not working in studio (with Strobes

triggerd with Radio trigger) I got balck stripes about 3 mm in the bottom of the images. Why , I can't under

stand. It works fine with shtter speed of 1/160 . But Why The Canon is like this? Any one has the similar

problem.? I have posted the same just 10 min ago but I could't found it the fourm. That's why I am posting

again.</p>

<p>It's not the camera, but a problem with the flash sync shutter speed. If you're using larger studio flash units, the shutter speed should be between 1/60 and 1/30. For non-Canon compact units, 1/200 would be fastest allowable shutter speed. Check page 104 of the camera manual.</p>

<p>User error.<br>

Do remember that the synch speed is a max, not fixed... i.e. you can use any speed up to 1/200th and still get flash synch.<br>

Unless you are working in an unusually bright studio then 1/200th is overkill.</p>

<p>Yes it is there in page 104 . But If I want fast shutter speed in studio ,is it not possible with Canon ?</p>

<p>you need to use "High Speed sync" to get fast shutter speeds with Canon flashes</p>

<p>It's neither a mistake jumping to Canon nor a mistake jumping to Nikon, it depends on how one prioritizes the features and benefits of each line. Don't second guess your decision, make the best of it and time will tell you if this was the best choice.</p>

<p>It would be interesting what Radio triggers and flash system you use. We have the Pocket Wizard system on Profoto Pro7/8 and that works fine. But just be on the safe side i shoot one click (third) down fro the highest sync speed and it never failed.<br>

I also tested the new PW TT5 on Profoto last month and they synced actually 1/3 higher than the sync speed of the cameras tested (1Ds III, 5DII).</p>

<blockquote>

<p ><a href="../photodb/user?user_id=1119106">Thangavelu Nachimuthu</a> <a href="../member-status-icons"><img title="Subscriber" src="http://static.photo.net/v3graphics/member-status-icons/sub6.gif" alt="" title="Subscriber" /> </a> , Oct 30, 2009; 07:37 a.m.<br>

Yes it is there in page 104 . But If I want fast shutter speed in studio ,is it not possible with Canon ?</p>

 

</blockquote>

<p>1/200th should be more than fast enough for most studio work.<br>

If your ambient lighting is under control then the exposure duration is effectively the duration of the flash, which is into the milliseconds. If you need faster still then you need strobe flashes, which is basically the mode the canon flash heads go into in high speed synch mode.<br>

But basically these limitations are the limitations of all focal plane shutter cameras, leaf shutter cameras (i.e. most medium format cameras) are traditionally used in studios for this reason.</p>

<p>Sorry, but I can't figure out if he thinks he needs the shutter to STOP action, or deal with a BRIGHT studio combined with some action, or to gain flash adjusted wider apertures ? Maybe upset over slight difference in the two cameras?</p>

<p>Higher shutter speeds tackle bright studio or sunshine issues. On the other hand, with a darker studio, electronic flash can stop almost ANYTHING indoors - i.e. bullet, spinning fan, models blown hair, etc.</p>

<p>You'll have the same problem with any brand camera. The slower syce speed is a limitation fo the lights and the triggering you have set up not the camera body. Some bodies can add even more lag. For example I shoot my canon dslrs at 1/100 in studio but I have to use 1/60 for MF film bodies.</p>

<p>The first thing you need to know is how the flash sync works. When the Canon 430EX flash fires a pulse it isn't an instantaneous pulse of light. The flash pulse (based on my own crud measurements) lasts about 1/180 of a second. For the camera to capture the image the sensor has to be completely exposed. That means the camera waits for the first shutter curtain to fully open, the camera fires the flash, and then the second shutter curtain closes. Longer shutter times (1/100, 1/30, 1sec etc.) work the same way. </p>

<p>However above 1/200 of a second the operation of the shutter changes. So if you set the exposure to 1/400 of a second the camera releases the first shutter curtain, and then releases the second shutter curtain while the first is still moving. So instead of the shutter opening and then closing you now have a open slit that travels across the sensor. If you fire the flash at such a speed only a portion of the sensor will see the light of the flash. </p>

<p>Nikon, Pentax, Olympus, and Sony DSLR cameras all work this way although there is some variation on flash sync speed and flash pulse duration. Almost all current DSLR are about 1/200 of a second, older cameras can be 1/100 to 1/60 of a second. The new 7D has 1/250 of a second shutter sync speed. Flash pulse length is seldom specified by the manufactures and it can very widely. Some can be very short at full power while others can be longer than 1/200 of a second. So for some studio flash setups you might have to use a shutter speed of 1/100 of a second or slower. The manual should state what the sync speed is.</p>

<p>If you want a faster shutter speed there are two things you can do:</p>

<ol>

<li>Reduce the flash power output. When the flash is set to 1/2 power the flash pulse last about about half as long. At 1/8 power the flash pulse is 1/8 as long as the full power pulse. A 1/2 power pulse is equivalent of 1/400 of a second shutter, while a 1/8 power setting will give you a pulse equivalent of about 1/1600 of a second. So while your camera shutter is still set to 1/200 of a second, the flash exposes the image at 1/1600 of a second when it is set to 1600 of a second. However this works best if all of the light on the subject must come from the flash. That means you must turn off the room lights first, make the exposure, and then turn the room lights back on. If you want to take a picture of a bullet set the flash to its lowest power setting and trigger it when the bullet is in front of the camera (a special trigger is required in this case and the camera shutter is typically set to bulb mode). You can still do this with some ambient light but you have to balance subject distance, aperture, and flash power to insure that most of the light comes from the flash. </li>

<li>Use Canon's High Speed Sync setting. Lets say your shutter speed setting is faster than 1/200 of a second and the shutter curtains are traveling across the sensor with a slit gap of 6mm. The High Speed Sync setting will then fire the flash 4 separate times to cover the entire sensor (the vertical side of the sensor on a full frame camera is 24mm. 24mm divided by 6mm = 4). This feature is built into the flash. Not all Canon flashes have this feature. </li>

</ol>

<p>The down side of both of these methods is that the flash power is reduced. This means you need to compensate by moving the flash and camera closer, increase iso, and or open the aperture further. </p>

<p>In regard to sync speed...as every one is saying, you will need to use a slower shutter speed. The 5D has a max sync speed of 1/200, however when I use my MicroSync radio slave (even when triggering Canon 580EX flash) the max speed is 1/180.</p>

<p>On that note, as I recall older Nikon DSLRs (I don't know what models) used an electronic shutter (even along with a mechanical focal plan shutter) and so you could sync up to something like 1/500 with radio slaves and no problems. This was talked about a lot on Strobist a while back before Nikon droped the electronic shutter and went with the mechanical shutter only. So if the OP used one of these older bodies, it may better explain the confusion. </p>

<p>Also as stated Canon shows the camera as working with 1/200 max sync speed (the OP is using radio slaves so talking about high speed sync is pointless) however with some radio triggers, the max speed is reduced a bit...should not be a real issue in a studio where things can be controled.</p>

<p>Jason</p>

<p>Thanks to every one . I am convinced now.</p>

<p>That advice to reduce flash output to shorten flash duration does not apply to all flash units. My understanding regarding Alien Bee flashes is that the shortest flash duration is ironically seen with a full power flash. In any case, the duration of the flash is so short that it will have little effect on sync speed, which is limited by shutter speed. It's easy to see why smaller sensor cameras have faster sync speeds, as the curtain has a shorter throw.<br /> <br /> The main issue here is the fact that radiotriggers (and studio flash) can produce slight delay, which may cause sync speed to be lower than published data for the camera. You might try hardwiring your flashes, to exlude your radiotriggers from the loop, and then test the limits of your sync speed. I suspect your radiotriggers are the culprit.<br /> <br /> In any case, sync speed should not be a critical issue for studio flash -- is it really that important for your purposes?</p>