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04-23-2015, 09:23 AM   #781
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QuoteOriginally posted by THoog Quote
I thought this (or the K-3II specs thread) was the "Why I won't buy a K-3 II" thread...
I won't buy the K3II because the only new body I need is one for myself, would like a body about 40 years younger.

If I was buying the new Pentax and it came out in three different models, one with flash, one with wifi and the third with GPS it would be the later I would buy followed by the flash and hte wifi last. I imagine that most people would have different orders of preferences.I seldom used the flash on my film cameras or the Kr and when I got the K5ii it came with the now discontinued 200 flash which is in my camera bag all the time. If I was using fill in flash more often I think the on board flash would be important to me, if I was not shooting landscapes the GPS would be less important.

I doubt that Pentax is expecting every K3 owner to upgrade anyways. If you want on board flash and do not have the K3 perhaps it is time to upgrade and if you have the K3 and want the GPS you could have two cameras as many already do and the cameras whould have different features. Pentax cannot go its own way if it has to be exactly like the big two feature for feature. At least not on the top APS model.

04-23-2015, 09:24 AM   #782
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QuoteOriginally posted by Mistral75 Quote
Nope, not as long as the shutter speed is slower than the synch speed: the flash itself lasts less than 1/1,000s and the resulting flash lightening power will be the same, be the shutter speed 1/125s, 1/180s or 1/250s.

It's HSS at shutter speeds faster than the synch speed that results in lower flash power since the flash unit emits a series of short strobes of lesser power, each of them lightening a portion of the final image (the portion corresponding to the window between the two shutter curtains).
Actually no. The Metz AF50-1 at 1/1 power is 1/250th of a second, at 1/2 it is 1/900. 1/4 to 1/16 it gets interesting as a way to freeze movement.

The sync speed it the fastest speed that the sensor is entirely exposed to light during the exposure. Faster speeds the trailing curtain follows the leading curtain across the sensor, and if a flash is used, gives a band of exposed area, the rest darker.

The limit is the shutter design and construction.
04-23-2015, 09:33 AM - 1 Like   #783
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QuoteOriginally posted by derekkite Quote
The limit is the shutter design and construction.
This should be the next area of work for Pentax R&D (of course in concert with their suppliers). Or they should just pay up for a better shutter.
04-23-2015, 09:34 AM - 1 Like   #784
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QuoteOriginally posted by derekkite Quote
Actually no. The Metz AF50-1 at 1/1 power is 1/250th of a second, at 1/2 it is 1/900. 1/4 to 1/16 it gets interesting as a way to freeze movement.

The sync speed it the fastest speed that the sensor is entirely exposed to light during the exposure. Faster speeds the trailing curtain follows the leading curtain across the sensor, and if a flash is used, gives a band of exposed area, the rest darker.

The limit is the shutter design and construction.
Ok, 1/250s instead of 1/1,000s is the maximum shutter speed to fire this cobra flash at full power (I had studio flashes in mind, the flash duration of which is shorter at full power).

As long as the synch speed is lower than 1/250s (in your example), you will get the same illumination power from the flash whatever the synch speed is and whatever actual shutter speed, lower than the synch speed, you are using.

At shutter speeds higher than the synch speed, the trailing curtain follows the leading curtain across the sensor, exposing a progressive band, as you wrote. In this case you need HSS (High Synch Speed): the flash fires several times during the exposure to successively illuminate several portions of the sensor. The flip side of the coin is that each flash then corresponds to a limited power : 1/4, 1/8, 1/16 or 1/32 of max power, depending on the number of successive flashes. There you 'loose' a lot of the flash's illumination power.

04-23-2015, 10:11 AM   #785
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QuoteOriginally posted by RGlasel Quote
Don't forget that flash power is a function of flash duration. Faster sync speeds mean less flash power. For an example, my Metz 52 AF-1 flash requires 1/125 second to provide full power. I don't need a faster shutter speed for group portraits in large rooms (about the only thing I need full flash power for) and there is always HSS for action shots at faster shutter speeds.
There are other kinds of flash such as ring flashes and power heads.

QuoteOriginally posted by JimC1101 Quote


I did not want to reply because someone might say that it went over my head again. :P
Yep. You overlooked power heads and macro flashes.


QuoteOriginally posted by RGlasel Quote
The sync speed it the fastest speed that the sensor is entirely exposed to light during the exposure. Faster speeds the trailing curtain follows the leading curtain across the sensor, and if a flash is used, gives a band of exposed area, the rest darker.

The limit is the shutter design and construction
.

Which is why the need for a sync speed. Otherwise none of this would matter and the 1/180 wouldn't be lagging behind Nikon etc.

Last edited by Blue; 04-23-2015 at 10:24 AM.
04-23-2015, 10:17 AM   #786
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QuoteOriginally posted by monochrome Quote
This should be the next area of work for Pentax R&D (of course in concert with their suppliers). Or they should just pay up for a better shutter.
I am not sure the shutter on the K-5 and K-3 or even the K-7 and K20d was really the problem because they are already more advanced than the other bodies. How tough would it be to get 1/250 out of them?
04-23-2015, 10:47 AM   #787
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QuoteOriginally posted by Mistral75 Quote
Nope, not as long as the shutter speed is slower than the synch speed: the flash itself lasts less than 1/1,000s and the resulting flash lightening power will be the same, be the shutter speed 1/125s, 1/180s or 1/250s.

It's HSS at shutter speeds faster than the synch speed that results in lower flash power since the flash unit emits a series of short strobes of lesser power, each of them lightening a portion of the final image (the portion corresponding to the window between the two shutter curtains).
No, he's correct. Some flashes have long durations (T.1 vs T.5 times). I've seen units that take 1/100s at full power. That means if you shoot at 1/180ths, you are cutting off some of the flash and decreasing its exposure.
04-23-2015, 10:48 AM   #788
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QuoteOriginally posted by monochrome Quote
This should be the next area of work for Pentax R&D
What benefits did you have in mind?

Assuming that the reason for Pentax using 1/180 as flash sync speed instead of 1/250 is that the leading and trailing curtains of the shutters Pentax uses move 28% slower (less than 1/2 stop) than the ones Nikon uses, does improving the shutter mean a faster minimum shutter speed? (Although the D7200 and K-3 have the same 1/8000 sec. spec)

Are you thinking of changing the style of shutter altogether? How many of us would give up faster shutter speeds (leaf shutters generally max out at 1/500 or slower) in order to get slightly faster flash sync?

Now, if the reason for Pentax lagging Nikon in terms of flash sync is that Pentax is using less reliable shutters, that can't be trusted to consistently leave the entire sensor exposed for less than 1/250, maybe all exposures could be improved with a better shutter?


Last edited by RGlasel; 04-23-2015 at 10:53 AM.
04-23-2015, 10:52 AM   #789
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QuoteOriginally posted by RGlasel Quote
What benefits did you have in mind?

Assuming that the reason for Pentax using 1/180 as flash sync speed instead of 1/250 is that the leading and trailing curtains of the shutters Pentax uses move 28% slower than the ones Nikon uses, does improving the shutter mean a faster minimum shutter speed? (Although the D7200 and K-3 have the same 1/8000 sec. spec)

Are you thinking of changing the style of shutter altogether? How many of us would give up faster shutter speeds (leaf shutters generally max out at 1/500 or slower) in order to get slightly faster flash sync?

Now, if the reason for Pentax lagging Nikon in terms of flash sync is that Pentax is using less reliable shutters, that can't be trusted to consistently leave the entire sensor exposed for less than 1/250, maybe all exposures could be improved with a better shutter?
Do you have a citation from Pentax that states that the shutter in the K-5 and K-3 is the hitch with this mythical 28% stuff? I don't think it is.
04-23-2015, 11:00 AM   #790
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QuoteOriginally posted by Blue Quote
Do you have a citation from Pentax that states that the shutter in the K-5 and K-3 is the hitch with this mythical 28% stuff? I don't think it is.
I don't, and I think you are right that differences in shutters between brands of camera aren't the reason for differences in flash sync speed. I really don't understand this obsession with flash sync speed, but I might be missing something.
04-23-2015, 11:14 AM   #791
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QuoteOriginally posted by RGlasel Quote
I don't, and I think you are right that differences in shutters between brands of camera aren't the reason for differences in flash sync speed. I really don't understand this obsession with flash sync speed, but I might be missing something.


I think this started with a comment where individuals had said they wish Pentax would increase the onboard flash sync speed to be greater than 1/180 just as Nikon does with 1/250 speed. I made a comment stating that Pentax fixed that problem by going from 1/180 to 0 on onboard now because there will not be an onboard flash on the K-3II. We all know that P-TTL HSS can go higher than 1/180. It kinda got off track and the point is moot, the K-3II and the upcoming FF will not have an onboard.
04-23-2015, 11:19 AM   #792
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QuoteOriginally posted by RGlasel Quote
I don't, and I think you are right that differences in shutters between brands of camera aren't the reason for differences in flash sync speed. I really don't understand this obsession with flash sync speed, but I might be missing something.
The reason you don't see "black out" on digital is that the camera's electronics over rides the shutter speed when the flash is on. With nature photography especially with sun, it would allow faster shutter speeds to be used at greater distances using an external flash for fill.
04-23-2015, 09:34 PM   #793
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QuoteOriginally posted by JimC1101 Quote
Apologies to all. I have not been trying to stir anything up intentionally but in my many years here, I have never seen such posts where so polarizes for and against and some people are trying to make it a war. I don't think of it in that way. As I said, everyone has requirements and to me, they are all valid to each of us. I would never try to tell someone to stop posting and move on, unless they are harsh or unfounded, because this forum is about discussing our opinions. Once again, apologies.
None needed in my opinion. This discussion got a little more polarized than usual. You have a (valid) opinion and nothing wrong with posting it. I don't agree (for me) but that's no reason for things to get heated. And if I was a little strong you have my apologizes.

The problem is there are three options:
WiFi
GPS
Flash

Some want one, or two. Some want none, or all. It appears that Ricoh feels the FLUCard solves the WiFi (on this model), and that GPS built in is more important than flash built in. From an engineering standpoint this solution is the only one that works if you only have room for flash or GPS because external GPS prevents flash use of any kind, while built in GPS still allows flash (using an external model).

Is that ideal? Obviously not to everyone. And I would really, really like to hear from Ricoh the reasoning behind dropping the internal flash. I'm curious if there is more to it than just lack of space.
04-24-2015, 03:06 AM   #794
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QuoteOriginally posted by RGlasel Quote
What benefits did you have in mind?

Assuming that the reason for Pentax using 1/180 as flash sync speed instead of 1/250 is that the leading and trailing curtains of the shutters Pentax uses move 28% slower (less than 1/2 stop) than the ones Nikon uses, does improving the shutter mean a faster minimum shutter speed? (Although the D7200 and K-3 have the same 1/8000 sec. spec)

Are you thinking of changing the style of shutter altogether? How many of us would give up faster shutter speeds (leaf shutters generally max out at 1/500 or slower) in order to get slightly faster flash sync?

Now, if the reason for Pentax lagging Nikon in terms of flash sync is that Pentax is using less reliable shutters, that can't be trusted to consistently leave the entire sensor exposed for less than 1/250, maybe all exposures could be improved with a better shutter?
Isn't the solution for faster sync speeds to use an electronic shutter for those situations? I don't know how much better 1/250 is versus 1/180. It is a half stop? Lets you open your lens from f2.8 to f2.4 more with a Nikon than with a Pentax. On the other hand, the Nikon D40 had a 1/500 flash sync speed (even though it wasn't a very good camera otherwise) because it used an electronic shutter. But I'm not an engineer to know how possible this sort of thing is.
04-24-2015, 04:43 AM   #795
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QuoteOriginally posted by jatrax Quote
None needed in my opinion. This discussion got a little more polarized than usual. You have a (valid) opinion and nothing wrong with posting it. I don't agree (for me) but that's no reason for things to get heated. And if I was a little strong you have my apologizes.

The problem is there are three options:
WiFi
GPS
Flash

Some want one, or two. Some want none, or all. It appears that Ricoh feels the FLUCard solves the WiFi (on this model), and that GPS built in is more important than flash built in. From an engineering standpoint this solution is the only one that works if you only have room for flash or GPS because external GPS prevents flash use of any kind, while built in GPS still allows flash (using an external model).

Is that ideal? Obviously not to everyone. And I would really, really like to hear from Ricoh the reasoning behind dropping the internal flash. I'm curious if there is more to it than just lack of space.
In the Q&A addendum of the Press Release Ricoh says space was the problem. For internal GPS removing the flash was the only option.
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