[Gooshin]

deja vous

deja vous is the wrong word here

this bullshit creeps up every single year, over and over and over again.

just mindless repetition, we should create a new term.

[tr13]

If you really want high FPS, you are not pro, and use it frequently - you don't need DSLR.
You need fast ultrazoom using CCD sensor with optical stabilization. Despite lower sensitivity, no rolling shutter, and good compacts have generally longer shutter life.
Shooting with high FPS have some advantages. For example, it is easear to catch interesting moment with ordinary people then you have not much time to shoot.

[Ratmagiclady]

I hate drama queens, show me a MEANINGFUL,TANGIBLE difference between 5 FPS and 6FPS

how do you think photographers back in the film days dealt with this?. they didn't spray and pray they anticipated the moment of peak action, and captured it. Most film cameras in the mid 1990s weren't half as fast as current DSLR cameras are.

When I did sports, usually with a winder in the neighborhood of 2 fps and change, I'd play music for rhythm and watch the players. By combining the two, you can have pretty good timing. Even if I leaned on the shutter I knew exactly when it was going to fire and I could alter that timing pretty well. (For batters, well, you watch *them,* they're already trying to time their gross motor actions to the arrival of the ball, so you just read *their* body-English and synch up to what they're doing. As someone said, it'd be pure luck to take a scattershot approach. I haven't timed it, but it looks to me that most of the interval you want out of a batter's swing is well inside even a 6fps winder's rate. It's not really about speed, it's about precision.

I think the reason Pentax hasn't gone with the high FPS shutters is cause it's a lot of engineering for something that hasn't been very useful to most of their market niche. And, as someone explained on some other thread, they could have the faster shutter and FPS if you went with a bigger shutter mechanism and related stuff. Focusing faster would be more of a priority to me, too.

[falconeye]

I have long thought about doing a test for this, not only for the issue about freezing action but with respect to flash duration.

Actual flash duration must be extremely short.

Current print copy of German fotoMagazin 2009/09 p.128ff has an issue about high speed photography written by Andreas Wietig (who otherwise just is a reader of the magazine).

One of his images is here:

fotoMagazin

He uses an acousto-electronic trigger, ordinary [d]SLR and flash to freeze high speed action such as a bullet. He recommends to use lowest flash power as it results in shortest flash duration. I can see the bullet in his photography. To freeze a bullet requires something like 1/50000s, I guess. On the internet, a value like 1/20000s is typically quoted as short flash duration

[Lowell Goudge]

Actual flash duration must be extremely short.

Current print copy of German fotoMagazin 2009/09 p.128ff has an issue about high speed photography written by Andreas Wietig (who otherwise just is a reader of the magazine).

One of his images is here:

fotoMagazin

He uses an acousto-electronic trigger, ordinary [d]SLR and flash to freeze high speed action such as a bullet. He recommends to use lowest flash power as it results in shortest flash duration. I can see the bullet in his photography. To freeze a bullet requires something like 1/50000s, I guess. On the internet, a value like 1/20000s is typically quoted as short flash duration

if 1/20000 is the shortest duration, and I want you to think about this, lets play the numbers game

lets allow 6 power steps in total between minimum and maximum, this has durations in total of

1/20000 s
1/10000 s
1/5000 s
1/2500 s
1/1250 s
1/613 s

this last step is 1.6mS and now becoming significant in the total timing

[falconeye]

if 1/20000 is the shortest duration, and I want you to think about this, lets play the numbers game

Well, somebody actually measured it for a Canon 580EX:

1/1 power = 1/1000 second
1/2 power = 1/2000
1/4 power = 1/4000
1/8 power = 1/9000
1/16 power = 1/15000
1/32 power = 1/21000
1/64 power = 1/30000
1/128 power = 1/35000

Flash duration of a Canon 580Ex flashgun | PhotosbyKev
Well, some strange curve but not very far off your guesstimate.

So, let's assume for Pentax to be on a safe side and leave the shutter open for 2x full power or 2ms.

Then the 5.55ms shutter open time would be divided into
2 ms full open time and
3.55 ms (or 1/282s) curtain travel time (which is 4.5m/s travel speed -- I can run faster ... )

[Pentaxor]

unless the subject motion is at right angles to the camera then focus is changing with motion and everything is out of focus.

With respect to this and other comments, why not look at the 30FPS HD vidio the K 7 can do? Again, for motion studies it will be better than still photos.

with this I will stop, there is no point going in circles

Lowell, I just remembered. he's not into the K-7's HD video capability. remember what he said, he'd rather have a K20D with 6fps than having a K-7. I think he already made up his mind, regardless of the reasons, alternative solutions on how to capture his precious game of baseball that supposedly knows much better than anyone here who shoots or does sports photography. actually, your suggestion of using the HD video in capturing point by point motion is the best solution for capturing such scenario which the OP considers as too critical to handle and only a 6fps camera could manage to capture. I don't think he would still imply on saying that a 6fps still photos would still be better in capturing baseball action compared a 30fps HD quality converted movie stills.

the thing is, there is no point in downsizing the capability of the K-7 if you can't have it or don't want it. it's clearly pathetic, looking for silly reasons not to like the K-7 for that. if you are contented the K20D, so be it. otherwise, buy a 50D as someone already stated. there's nobody forcing you not to. of course, with a 6fps camera, there's no need to focus properly, need a tripod or time your shots to capture those precious baseball moments as someone would reiterate. a 6fps would be enough.

[Edvinas]

Actual flash duration must be extremely short.

Current print copy of German fotoMagazin 2009/09 p.128ff has an issue about high speed photography written by Andreas Wietig (who otherwise just is a reader of the magazine).

One of his images is here:

fotoMagazin

He uses an acousto-electronic trigger, ordinary [d]SLR and flash to freeze high speed action such as a bullet. He recommends to use lowest flash power as it results in shortest flash duration. I can see the bullet in his photography. To freeze a bullet requires something like 1/50000s, I guess. On the internet, a value like 1/20000s is typically quoted as short flash duration

One Lithuanian guy is using the same technique to get quite spectacular shots:
Linas Liaukonis. Akimirkos.