experiences with f280 flash

<p>I've seen people touting the F280 full sync flash around on the forum as the be all and end all to automatic flash. I wanted to get an idea of how good it is and how often people use it where a normal TTL flash wouldn't have done the job.</p>

<p>I agree that it is a somewhat revolutionary flash, but I'm trying to get an objective view of is it worth the expense of the Om-4ti + the flash? I've used medium format cameras for a while with leaf shutters, so the ability to sync at any speed is not new to me.</p>

<p>so, I'd like to know from people who have the flash, what situations you use it for? how you use it (ie. do you use it as a flash or do you try to balance ambient/flash light; how do you know how much of each you'll get). And how often do you use it where a t32 or other flash wouldn't have also done the job. Do you find that you take shots that you wouldn't have otherwise been able to take?</p>

<p>I had on many years ago but couldn't get along with it, so I sold it. I think the main problem was that I couldn't work out what it was doing. With ordinary flash, particularly fill in, it's quite easy to balance ambient and flash. I find it's getting the balance right that makes a good picture so I prefer to do this manually. I know with my flashgun (GN 28 and with 100ASA film), at f5.6 and 4 paces I'm illuminating my subject correctly. I then set the shutter speed for ambient (i.e. the background). If I would need a shutter speed faster than 1/60, I move in a step and use f11; and so on (I'm sure you know all this, Tim!). It's quick so I don't miss shots and my subjects don't look bored (well, hopefully!). In auto mode I couldn't get an idea of what the F280 was doing and it was too complicated to use manually: effectively the GN is dependent on the shutter speed. You would need to carry around a look-up table! Also, I did not find it much of an advantage being able to synchronise at high shutter speeds because the effective GN is so small, GN 4 at 1/1000 I seem to remember. The F280 is a good idea and no doubt in the right hands you can get the result you want...but I prefer a normal flash and accept its limitations. It was to better balance flash and ambient under high contrast conditions that I bought an OM2000 (1/125th flash sync) and I have been very pleased with it.</p>

When I submitted my response, I had a 'counted out' message and assumed it had not been accepted. I tried several times with the same result. Imagine my horror when, after going away to get a cup of tea, I found all my attempts posted on the website! I've deleted all the responses but cannot delete the headlines. Sorry!

<p>The F280 was a way for Olympus to work around the fact that getting fast flash synch with a horizontally traveling shutter is difficult. Canon's F-1 cameras and Nikon's F2 both had horizontally traveling titanium foil shutters with a top speed of 1/2000. The novelty of the OM4 models was that they kept a cloth horizontal shutter and still managed to get the 1/2000 top speed. Based on the need to pulse the flash to achieve an effective high speed synch, the Olympus system was not going to provide the high speed synch with adequate power to cover a long flash to subject distance. It was more suited to macro and close-up work. Years later Cosina made the OM2000 for Olympus. That camera has a vertically travelng shutter and a 1/125 flash synch speed. The Nikon FE2, with its top shutter speed of 1/4000, had a flash synch speed of 1/250. <br>

If I am not doing close-up or macro work and want to be able to synch at any speed I use a Bronica ETR, SQ or GS series camera. All the lenses have leaf shutters and synch at all speeds. It helps to have a flash with a variable power setting if you want to do fill flash work. My Minolta X-700 cameras have a slow 1/60 synch speed but with a Sunpak 522 or Minolta 360PX I can vary the power output of the flash. In TTL mode with the 360PX I can also use the exposure compensation dial. With a 35N back on an ETR/S/Si you can use 35mm film. The 75/2.8 makes a nice short portrait lens and you have flash synch at all speeds.</p>

<p>Yeah, as you do Jeff, I use a camera with a leaf shutter (Mamiya RB67) when I want to use flash and sync faster than 1/60. I also just got a Vivitar 285HV and I've been working my way through some of the strobist articles and playing around with off-camera flash.</p>

<p>I guess, I posted this response after seeing some threads advertising the F280 flash compatibility of OM3/4ti as one of the major benefits. However to me it doesn't sound like that much of a benefit since the feature has limited use and it has a near useless guide number when used in this fashion. Certainly to me this feature alone wouldn't justify the price difference between an OM4 and an OM4ti.</p>

<p>And it seems that every time Olympus OM and Flash gets mentioned in the same topic, the discussion always leads towards the F280 as being the best thing in the world ;)</p>

<p>My take on balancing ambient & flash is that I meter the ambient light in the scene and set the exposure on the camera based on what I want the ambient light to give me (ie. usually I'll underexposure the background by 1-2 stops), and make sure I'm using 1/60 or slower. Then I will use the guide number + aperture to calculate the flash distance and then position the flash at that distance at the angle that I want. The method I use seems very simple to me and produces predictable results, the f280's method of fill-in flash at any speed relies on the computer in the flash and I think I would find it hard to gauge what it's going to do.</p>

<p>Anyway, Jim the guide number doesn't normally take into account the shutter speed at all. It could be different with the F280, however normally...<br>

Guide number = distance * fstop<br>

So, the Vivitar 285 has a guide number of 36m at 100iso means that at f/1 the flash will illuminate a subject at 36m distance correctly.<br>

So, you can calculate the distance by using the above formula. So with GN=36<br>

f/2.8 = 36/2.8 = 13m<br>

f/8 = 36/8 = 4.5m<br>

So, say you have a subject at 9m distance.<br>

to calculate the fstop.... 36/9 = 4 so you need to use f/4 with iso100 film<br>

It's a useful formula to know if you know what the GN of the flash is at manual power setting.</p>

<p>Anyway.... that exhausts about all I know about flash</p>

<p>I took a look at the manual for the f280 and it gives a table of different guide numbers in super fp mode based on the shutter speed! I guess this is what you were referring to so I take your point there.</p>

<p>The FP mode works by having the flash 'ON' for the whole time the curtains are travelling across the film -a few milliseconds, I guess. In this way, the whole film is illuminated by flash at all shutter speeds. Effectively, its just like switching on a light and taking a picture...but this means that both the shutter and the aperture must be set to get the right 'flash' exposure...and of course you have ambient to worry about as well! As I said, too complicated for me! At least with ordinary flash you can control the ambient by setting the shutter speed without affecting the flash, up to the flash synchronisation speed. </p>

<p>Thinking about it a bit more, the F280 can't control the flash duration (like a conventional AUTO flash) because the flash has to be ON while the curtain moves across the film plane. It must control the flash intensity. Presumably it takes the exposure reading from the camera then sets the flash intensity accordingly. The trouble is, what does 'accordingly' mean? The flashgun may get the exposure reading from the camera but the camera certainly does't tell it how far away the subject is. Maybe there's some kind of distance measuring unit behind the red window on the flashgun? Certainly we don't easily know the chosen flash/ambient ratio (in AUTO) or it's complicated (in MANUAL) and in any case the range of the 'FP flash' is limited.<br>

</p>

<p>I agree with the criticisms above. Olympus, to my mind, occasionally suffers from what I think of as half-assed innovation. They came up with a great idea in terms of the FP setting on the F280 flash, but then never bothered to develop a bracket or grip that would allow the flash to be used off-camera. (If you stick the F280 in the Grip 2, the FP feature won't work). Likewise, the F280 doesn't swivel or tilt, even though these kinds of features were commonplace in many brands of flashes, including earlier OM system flashes. Just like when they stuck for years with those horrible plastic screw-in hot shoes that proved to be so easy to break. Olympus knew how fragile they were early on, but they kept on making the damned things until the OM-2S/OM-3/OM-4 bodies came out. Olympus could have accomplished the same system versatility with a sturdy, on-camera hot shoe and a plug-in module for off-camera flash.</p>

<blockquote>They came up with a great idea in terms of the FP setting on the F280 flash, but then never bothered to develop a bracket or grip that would allow the flash to be used off-camera.</blockquote>

<p>The <a href="http://olympus.dementia.org/eSIF/om-sif/flashphotogroup/ttl_auto_cord_f.htm">TTL Auto Cord F 0.6</a> is designed solely for off-camera use with the F-280. The cord is not compatible with T-series units. It can therefore be used on any bracket with a shoe.</p>

<p>I've got the F280 too, but haven't used it yet, because I didn't know HOW to use it.</p>

<p>I've just checked the mir.com.my and olympus.dementia.org pages about F280, and it seems to me, that to use it for fill-in in manual mode, you need to adjust distance from subject according to the ambient light.</p>

<p>So for example if the ambient reading gives you 1/125 f/11 (typical sunny day exposure for 100ASA film) you need to be 1m from your subject to get the subject illuminated by flash light only, or 1,4m to get 2:1 ratio of ambient:flash light. G.N. at 1/125 is 10.4<br>

The same distances are correct even if you change film speed, because according to "sunny 16" rule, for 400ASA you would need 1/500 f/11 exposure, and at 1/500 and 400ASA(!) the G.N. of F280 is again 10.4 and the f-stop remains the same.<br>

If we change the exposure of the first example to an equivalent combination of 100ASA 1/500 and f/5.6, the G.N. changes to 5.2 and again, the correct distance is approximately 1m.<br>

If however the light changes, and the light meter says 100ASA, 1/125 f/5.6 (overcast day) the G.N. is 10.4 and the correct distance according to the f-stop is approximately 2m.</p>

<p>=> it seems it only depends on the amount of ambient light.</p>