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02-01-2013, 08:13 AM   #61
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QuoteOriginally posted by Anvh Quote
It's when your only control over the ambient light is the camera that shutter speed becomes important.
You are also forgetting about ISO and the aperture, many stock agencies refuse to take images with obvious flaws such as excessive CA or PF. Also you are better off using a smaller aperture because with product photography your client will most likely want the product to be visible, ja?

Don't forget when it comes to working with ambient light you can get away with a great deal just by using reflectors/flags/gobos.

02-01-2013, 11:06 AM   #62
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This can't be achieved with reflectors and gobos.



This photo was shot at 1/1000th @ f/5.6 ISO 200 using HSS mode. The flash, my Metz 58 AF-2, was at full power, but as you can see, some of the clouds, particularly near the sun in the upper right corner of the frame are blown out. Because I'm at such a high sync speed, the flash is doing everything it can to illuminate my subject, but in reality only a fraction of it's light is reaching the sensor. I probably could have achieved the same look with more detail in the clouds at 1/500th if my sync speed could reach that high, and the flash could have dropped by at least a stop in power giving me faster recycle times and more shots. Even if it couldn't, the first couple stops once you cross into HSS territory are still pretty useful, but having a 1/180th sync speed is like starting a 100 meter foot race 20 meters behind everyone else, you'd have to run that much faster in order to win.

Now I understand that good mechanical shutters are expensive, but there are other ways to achieve higher effective sync speeds, leaf shutters, mechanical-electronic hybrid shutters, and "hyper syncing". For me the whole argument boils down to creativity, not which company has what. It's like if I asked you to paint a picture and gave you a tube of white, a tube of black, and a 3 inch house brush. It can be done, but wouldn't you rather have a whole assortment of colors and an array of brushes for different types of strokes?

Not everyone is foolish enough to shoot with the sun in their frame, but I am, I like the effect. I think Pentax thinks of features in terms of "This will be good enough for most people", but what they should be thinking, if they want to maximize their appeal to the broadest ranger of shooters is "Most folks won't need or use this feature, but there are some who will want to take full advantage of it." I see that design philosophy from Nikon in particular, and to some degree from Canon. Now before you say "well why don't you switch?", believe me, I'm very close to doing so. But I do love my Pentax glass, and it's going to be hard (on my wallet) to find it's equal with Canon or Nikon. I'd be hamstrung for quite some time.

Last edited by maxfield_photo; 02-01-2013 at 12:06 PM.
02-01-2013, 12:10 PM   #63
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QuoteOriginally posted by maxfield_photo Quote
This can't be achieved with reflectors and gobos.



This photo was shot at 1/1500th @ f/5.6 ISO 200 using HSS mode. The flash, my Metz 58 AF-2, was at full power, but as you can see, some of the clouds, particularly near the sun in the upper right corner of the frame are blown out. Because I'm at such a high sync speed, the flash is doing everything it can to illuminate my subject, but in reality only a fraction of it's light is reaching the sensor. I probably could have achieved the same look with more detail in the clouds at 1/500th if my sync speed could reach that high, and the flash could have dropped by at least a stop in power giving me faster recycle times and more shots. Even if it couldn't, the first couple stops once you cross into HSS territory are still pretty useful, but having a 1/180th sync speed is like starting a 100 meter foot race 20 meters behind everyone else, you'd have to run that much faster in order to win.

Now I understand that good mechanical shutters are expensive, but there are other ways to achieve higher effective sync speeds, leaf shutters, mechanical-electronic hybrid shutters, and "hyper syncing". For me the whole argument boils down to creativity, not which company has what. It's like if I asked you to paint a picture and gave you a tube of white, a tube of black, and a 3 inch house brush. It can be done, but wouldn't you rather have a whole assortment of colors and an array of brushes for different types of strokes?

Not everyone is foolish enough to shoot with the sun in their frame, but I am, I like the effect. I think Pentax thinks of features in terms of "This will be good enough for most people", but what they should be thinking, if they want to maximize their appeal to the broadest ranger of shooters is "Most folks won't need or use this feature, but there are some who will want to take full advantage of it." I see that design philosophy from Nikon in particular, and to some degree from Canon. Now before you say "well why don't you switch?", believe me, I'm very close to doing so. But I do love my Pentax glass, and it's going to be hard (on my wallet) to find it's equal with Canon or Nikon. I'd be hamstrung for quite some time.
when I see shots like this, I have to ask why not use, for example a better beamer on the flash to narrow the beam, since most of the flash light presently is just missing the subject.

Also, when you consider that HSS cuts the guide number substantially, stopping down more, and cutting the ISO to 100 might actually have given you more headroom than trying to control/offset the background lighting with HSS.

The big point you are missing, and everyone screaming for faster HSS is in the same position, they just do not understand that increased sync speed also requires a new flash , with substantially higher light output for a much shorter duration, in order to achieve the same guide number. Faster sync is simply not as easy as people think, because the short durations required will involve extremely bright flashes, that get very hot, and are audibly very loud due to the energy discharge. Aside from that, no one has a focal plane shutter at 1/500 sunc speed to begin with, and the forces in the shutter will rise exponentially with speed, and life is cut by an order of magnitude for each doubling of load. so even if yyou do some day get higher sync speeds I don't ever want to hear complainte about shutter life, flash gun life, etc. etc...

until we get electronic shutters that is.
02-01-2013, 12:30 PM   #64
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am just trying to take my first HSS shot so I can understand this thread better.
Ist ds with AF360fgz, the ist ds manual page 155.
The ist ds is in m mode with M lens and HS is selected on the flash
I tried all modes TTL>A>M but the shutter speed is not adjustable above 180th.
When the flash is in SB, the faster speeds are available on the ist ds.
What am I doing wrong?

02-01-2013, 12:37 PM   #65
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OK, hold the phone on the above, I stuck a DA lens on and now i can take nice flash shots up to to 4000th.
How does the flash do that? Is it burst firing?
02-01-2013, 12:45 PM   #66
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Actually this was shot with a 12mm lens, and I was standing about 2 feet from her. The flash was set to it's widest setting, but at 2 feet away (I was holding it in one hand, attached to a TTL cord) the flash is actually falling off at the bottom of the frame. A better beamer would not have produced a desirable result. I really wanted to use my Lumiquest LTP softbox, but I had to take it off because the flash just wasn't strong enough.

Setting the camera to ISO 100 would have lowered the ambient a bit, and then I wouldn't have had ro resort to 1/1000th, which as you say diminishes the flash output considerably, but the camera has better dynamic range in "D-range" mode at it's native ISO of 200. The clouds would have been equally blown out at 100. "Just put a CPL or a ND filter on the lens." you say? Sorry, the Sigma 8-16 doesn't accept them.

Increased sync speed most certainly does not require a new flash. My old analog Metz 45CL-4 syncs perfectly well with my PZ-1p at 1/250th, and even my old Yashica A with it's 1/300th leaf shutter as does the Metz 58 (glad I bought a Cactus trigger and not a Yongnuo though). It doesn't matter to the flashgun at what speed the camera syncs. You can buy the same Metz 58 for Canon and Nikon and it syncs at 1/250th and even hyper syncs using the PocketWizard mini and flex system. And for the record, Canon does have a 1/500th shutter in their 1D. If Pentax would allow us to disable "black bar protection", we could do all sorts of neat tricks like hypersyncing or cropping out the black bars in post.

More flexibility is a good thing, you may not always need it, but it's nice to have when you do. If you don't want a faster shutter, rejoice, I hear the K5 is a great camera, but those of us who want a faster sync speed are S.O.L.
02-01-2013, 03:18 PM   #67
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QuoteOriginally posted by Anvh Quote
Well that's the reason why you want higher sync speeds, not for freezing things like you're suggesting earlier.

You want higher sync speed so you can lower the daylight while using a flash, and still use a wide aperture or without having to use the flash at full power.

You can certainly manage with 1/180 outside but a bit more would be welcome.
Certainly if you plan to use the flash light as your main light.


ps. LCD shutter these days can go down to 1/1000 and that's the full shutter area so that is also your sync speed.
I doubt we will see them on smaller sensored camera soon but on a medium format they would make sense actually.
It removes a fairly big moving part with a static part meaning less camera shake.
With medium format you also useally shoot with higher f-numbers so the slightly slower max shutter speed is not that much of a problem.
I was not trying to imply that I was trying to freeze action, but merely trying to balance out the daylight with the shadow, while shooting directly into the sun, and I have never had any probs. I do agree however that lcd shutters would be fantastic on any camera, if they have improved directly in proportion to the the lcd screens have.. No moving parts,no camera shudder,no problem sync at any speed.. Like you say I doubt we'll see them on 35mm cameras.. But you never know, maybe the manufacturers monitor these sites to see whatt the real users want, that would also be a great selling point.. Pentax please note.
02-01-2013, 05:40 PM   #68
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QuoteOriginally posted by Lowell Goudge Quote
The big point you are missing, and everyone screaming for faster HSS is in the same position, they just do not understand that increased sync speed also requires a new flash , with substantially higher light output for a much shorter duration, in order to achieve the same guide number. Faster sync is simply not as easy as people think, because the short durations required will involve extremely bright flashes, that get very hot, and are audibly very loud due to the energy discharge
Interesting fact - the "pop" sound we hear when a flash discharges is actually a sonic boom contained in the flashtube, the discharge of a flash is basically a stroke of lightning. Yes we are going to need a new flash, I will state for the record the rise time of the AF540FGZ is really slow compared to other makers - at 1:1 power the AF160FGZ is actually faster than the AF540 and the flash heads on that thing are massive* when compared to the pentax AF540. Hopefully the newer AF360FGZ is going to have a faster timings, but as Lowell mentions there is always the problem of overheating - the Nikon SB900 is famous for this problem, and frankly the only way I think it can be tackled is by using solid state capacitors using passive heat dissapation through an internalised heat sink. The problem with the SB900 is that Nikon is the positioning of the battery compartment (The batteries get very hot** - don't even think of using lithium batteries in a SB900) and the use of wet capacitors - and they are notorious for having heat problems when run continuously at full capacity. Solid state capacitors have a longer life, are considerably smaller and are able to be cooled effectively using conventional methods.


*120mm in length Vs 40mm
**Actually if you overwork any modern shoe mount flash you will inevitably melt something, usually the plastic fresnel in front of the flash head is the first thing to go south.


Last edited by Digitalis; 02-01-2013 at 05:54 PM.
02-01-2013, 11:22 PM   #69
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QuoteOriginally posted by wombat2go Quote
OK, hold the phone on the above, I stuck a DA lens on and now i can take nice flash shots up to to 4000th. How does the flash do that? Is it burst firing?
You got it. In HSS mode the flash continually pulses a series of small bursts for the entire time that the curtains are in motion, which coincidentally is the max sync duration. There is a drawback though, a big one. For a flash to mimic a continuous light, it takes a lot of energy. So much so that full power in HSS mode is only about as bright as one quarter power in normal mode, and that's at the slowest HSS speed. As the shutter speed increases, there is, effectively, an ever-narrowing slit formed by the shutter curtains that travels across the sensor. At 1/4000th of a second, it may be as small at 10% of the frame height (I'm kind of guessing), which means that at any one point in time, 90% of the sensor is covered by curtains and the light is just bouncing off of them. So not only are you starting with 1/4th power at the lowest HSS speeds, but it just goes downhill from there as shutter speed increases.

It's good not to cross over into HSS speeds if you can help it (because your guide number essentially drops 75%), but for the first stop or two, it's still somewhat useful for restoring detail back into an over exposed sky or background, after that it's pretty much rubbish at anything but point blank range. Of course having a more powerful flash helps.

But, having a higher sync speed also improves HSS efficiency in two ways. First, since the flashgun must pulse for the entire time the curtains are in motion, having a higher sync speed means the light doesn't have to stay on as long. In fact simply increasing the sync speed from 1/180th to 1/250th makes the 'on time' 27% shorter, meaning the flashgun can put more power into each pulse. Secondly, since the shutter curtains travel faster in a 1/250th shutter, the moving slit at any given speed over max sync is wider than that of a 1/180th shutter at the same speed, which means that more light can reach the sensor.

[EDIT: P.S. to answer your other question, HSS mode is pTTL based. The *Ist DS is one of the few cameras that can do both TTL and pTTL, but HSS will only function in the latter. You might look in the users manual and see if there's a way to force the camera into pTTL mode with older lenses. I've read about a K-mount hack that involves shorting some of the pins in the camera mount with foil, but I've never tried]

Last edited by maxfield_photo; 02-01-2013 at 11:33 PM.
02-02-2013, 12:25 AM   #70
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QuoteOriginally posted by Lowell Goudge Quote
when I see shots like this, I have to ask why not use, for example a better beamer on the flash to narrow the beam, since most of the flash light presently is just missing the subject.

Also, when you consider that HSS cuts the guide number substantially, stopping down more, and cutting the ISO to 100 might actually have given you more headroom than trying to control/offset the background lighting with HSS.

The big point you are missing, and everyone screaming for faster HSS is in the same position, they just do not understand that increased sync speed also requires a new flash , with substantially higher light output for a much shorter duration, in order to achieve the same guide number. Faster sync is simply not as easy as people think, because the short durations required will involve extremely bright flashes, that get very hot, and are audibly very loud due to the energy discharge. Aside from that, no one has a focal plane shutter at 1/500 sunc speed to begin with, and the forces in the shutter will rise exponentially with speed, and life is cut by an order of magnitude for each doubling of load. so even if yyou do some day get higher sync speeds I don't ever want to hear complainte about shutter life, flash gun life, etc. etc...

until we get electronic shutters that is.
Then why can you do HSS when a pentax flash is mounted on the camera? Why should it suddenly change off the camera? My radio triggers are capabpe of it. It does only work at lower power, but why cripple it?
I have uses for higher flash sync in some situation where i have to comprimise and work around it. Wouldnt it be better for me to create my vision, or almost get it right?.....
02-02-2013, 05:59 AM   #71
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QuoteOriginally posted by sbroadbentphoto Quote
Then why can you do HSS when a pentax flash is mounted on the camera? Why should it suddenly change off the camera? My radio triggers are capabpe of it. It does only work at lower power, but why cripple it?
I have uses for higher flash sync in some situation where i have to comprimise and work around it. Wouldnt it be better for me to create my vision, or almost get it right?.....
You can do HSS off camera with the *istD using the internal flash of the *istD as the master. Only Pentax camera I know of that can do this, I don't know why they changed koto be honest.
02-02-2013, 06:05 AM   #72
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QuoteOriginally posted by maxfield_photo Quote
Increased sync speed most certainly does not require a new flash. My old analog Metz 45CL-4 syncs perfectly well with my PZ-1p at 1/250th, and even my old Yashica A with it's 1/300th leaf shutter as does the Metz 58 (glad I bought a Cactus trigger and not a Yongnuo though). It doesn't matter to the flashgun at what speed the camera syncs. You can buy the same Metz 58 for Canon and Nikon and it syncs at 1/250th and even hyper syncs using the PocketWizard mini and flex system. And for the record, Canon does have a 1/500th shutter in their 1D. If Pentax would allow us to disable "black bar protection", we could do all sorts of neat tricks like hypersyncing or cropping out the black bars in post.
The flashes you mention we're designed for much shorter duration than the AF 540FGZ , my old Pentax AF500FTZ also supports 1/250. Why you might ask, simply because it was designed to. Go back a few pages and you will see that I have already commented on this, but the AF500FTZ simply does not support P-TTL so it is of little use.

Remember, the flash has to completely end before the shutter begins to close or you get banding, and this is already reported at full power and 1/180 for the AF540FGZ at max power, so to go to 1/250 sync with a shorter open period for the shutter, yes we do need a new flash. Now, here is where aftermarket might have an advantage, because they make flashes to suit canikon as well, and an aftermarket flash likely will have the shortest duration of all the camera makers, so that it works with the fastest shutter. Something to think about
02-02-2013, 06:35 AM   #73
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Hey Maxwell, Thanks for the good explanation at #69.
I have never used it but HSS might be good for the outdoor summer parties, so I will get some practise.
02-02-2013, 08:06 PM   #74
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The AF540 has a long flash tail, it's true, but there is actually very little light being emitted by the end of it. Our own Astro Dave has measured the duration of the unit, and you can read about it here http://photodave.us/AF540FGZ/
At full power, the t.1 duration of the AF540 is actually shorter than you might think, 1/200 of a second, and the P90 time as he calls it (the point at which 90% of the power has been emitted) is 1/243. But that's a full power. The t.1 duration of the Metz 58 at full power is actually longer at 1/125th.

But all these number are at full power, half the point of a faster sync speed is to lower the ambient light levels so that the flash can balance the ambient with less power. If the flash is having trouble balancing with the ambient light at full power at 1/180th shutter speed because of the long flash tail, increasing the shutter speed to 1/250th means the flash can drop to 3/4th power which shortens the flash duration. It's kind of counter-intuitive, I know, that increasing the shutter speed actually allows more of the flash to be captured, but look at the measurements. By half power, the t.1 time is 1/800th and the P90 time is 1/939th. That's almost within the duration of the fastest leaf shutters, but of course with that much ambient light being quelled, you can afford to open up a stop or three, and lower the flash power even more.

I don't know, am I missing something?

Last edited by maxfield_photo; 02-02-2013 at 08:15 PM.
02-04-2013, 05:49 PM   #75
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QuoteOriginally posted by maxfield_photo Quote
Not everyone is foolish enough to shoot with the sun in their frame, but I am, I like the effect. I think Pentax thinks of features in terms of "This will be good enough for most people", but what they should be thinking, if they want to maximize their appeal to the broadest ranger of shooters is "Most folks won't need or use this feature, but there are some who will want to take full advantage of it."
??? On the contrary: In general Pentax has always been known to take chances and develop unique cameras and lenses. Regards
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