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05-31-2009, 03:59 PM   #166
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QuoteOriginally posted by Prognathous Quote
Shutter noise can be an issue and can make you take less photos if you care at all about the people around you.

You didn't relate to the point I raised in second question. Here it is again:

"Can you give an example where using 1/250 HSS instead of 1/250 X-sync would make the difference between capturing the image and having to give up completely?".

1/250 HSS vs. 1/250 X-sync - what's difference does it make for you?

Prog.
I did relate to your question. I told you no, I can't give an example where using 1/250 HSS instead of 1/250 X-sync would make the difference between capturing the image and having to give up completely because I never give up completely, even when I'm working with a limitation on my gear (which is always). When I want a shot badly enough I get it - period. I can tell you that when I need 1/250 X-sync though, 1/250 HSS is not even almost the solution. Not unless I have more than one HSS enabled flash.

When I need 1/250 or 1/500 X-sync my solution is to shoot at the 1/180 limitation I'm stuck with, add a neutral density filter and pump more light in there from a pair of off camera Vivitar 4600 flashes. If that makes sense to you then you can probably figure out why I don't use HSS in those situations without me having to spell it out for you. If it doesn't make sense to you, especially after the limitations of HSS have been covered several times in this thread alone, then ... never mind.

05-31-2009, 04:05 PM   #167
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QuoteOriginally posted by Canada_Rockies Quote
I have shot a wedding where cameras were not allowed in the nave at all. I used the A 70-210 from the "crying room" in the balcony through a window. It is not unheard of that the sound of a camera, or the flash, or both, or even the presence of the photographer in the aisle is not appreciated.
The K-7, quiet shutter and all, would not solve that particular limitation. In that case, you would need a hidden camera with a silent shutter that operated through a hole in your lapel since they probably wouldn't even let you wear your hat cam in that sanctuary. Sounds like the K-7 is a total miss for you.
05-31-2009, 08:42 PM   #168
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QuoteOriginally posted by GoldenWreckedAngle Quote
The K-7, quiet shutter and all, would not solve that particular limitation. In that case, you would need a hidden camera with a silent shutter that operated through a hole in your lapel since they probably wouldn't even let you wear your hat cam in that sanctuary. Sounds like the K-7 is a total miss for you.
In that situation I was not using the K10, nor was I using the MZ-S, nor even the SF-1. I was using my KX, which is long gone. A tripod, Ilford XP-1 and away we go!
05-31-2009, 10:20 PM   #169
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QuoteOriginally posted by GoldenWreckedAngle Quote
I wonder... As I understand it, electronically shutting off the CMOS sensor (electronic shutter) is not an option, but what about turning it on electronically. It sounds like the limitation with the mechanical shutter is the inability to open the first curtain all the way faster than 1/180.

Would it be possible to open the first curtain all the way, turn on the sensor, then snap the second shutter closed? I think we could hit some pretty impressive synch numbers if possible.

There is a way... It must be found.
I do not think this will solve it. The problem is if the whole frame area is allowed to be opened, the second shutter has too much distance to cover in the small time required.

Pentax could offer a 55mm in the lens shutter with 1/1000 xync or slightly less. It could be special order and the few people that really need this vs. hi speed sync flash, could have it and we could stop talking about it.

Or maybe some clever person could design a leaf shutter that mounts on the camera somewhat like an extension tube. Of course it would be activated manually.

06-01-2009, 03:58 PM   #170
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QuoteOriginally posted by Photomy Quote
I do not think this will solve it. The problem is if the whole frame area is allowed to be opened, the second shutter has too much distance to cover in the small time required.

Pentax could offer a 55mm in the lens shutter with 1/1000 xync or slightly less. It could be special order and the few people that really need this vs. hi speed sync flash, could have it and we could stop talking about it.

Or maybe some clever person could design a leaf shutter that mounts on the camera somewhat like an extension tube. Of course it would be activated manually.
I think a TC with leafshutter will be more useful. You can use all your lenses and you loose as much sharpness as a NDfilter.
06-01-2009, 07:46 PM   #171
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QuoteOriginally posted by Photomy Quote
I
Or maybe some clever person could design a leaf shutter that mounts on the camera somewhat like an extension tube. Of course it would be activated manually.
You actually are on to something, my good man.
A quick measure tells me that a Copal #1 shutter will cover (just) the front element of slower 50mm lenses such as the A 50/1.7 or M50/2.0.
It might be necessary to stop down a little.
This would give a sync speed of up to 1/400 second by firing the flash off the leaf shutter.
It actually would take a surprisingly small amount of cleverness to attach it to a 49mm filter ring.
There is no compelling reason for the leaf shutter to go between the camera body and the lens. It can go anywhere in the light path as long as it's big enough.
06-02-2009, 09:38 AM   #172
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QuoteOriginally posted by Wheatfield Quote
You actually are on to something, my good man.
A quick measure tells me that a Copal #1 shutter will cover (just) the front element of slower 50mm lenses such as the A 50/1.7 or M50/2.0.
It might be necessary to stop down a little.
This would give a sync speed of up to 1/400 second by firing the flash off the leaf shutter.
It actually would take a surprisingly small amount of cleverness to attach it to a 49mm filter ring.
There is no compelling reason for the leaf shutter to go between the camera body and the lens. It can go anywhere in the light path as long as it's big enough.
I've never fired a leaf shutter but the mechanics of it seem like it would introduce a pretty strong vignette. I tend to post process a vignette around my subjects anyway so that might actually be a plus. I know so little about large format that I didn't even realize there were external shutters that might be adaptable to the end of many lenses. I'm learning a lot today thanks to Google and this thread.
06-02-2009, 09:54 AM   #173
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For those sharing my limited knowledge of leaf shutters, this article is worth a read.

06-02-2009, 10:02 AM   #174
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QuoteOriginally posted by GoldenWreckedAngle Quote
I've never fired a leaf shutter but the mechanics of it seem like it would introduce a pretty strong vignette. I tend to post process a vignette around my subjects anyway so that might actually be a plus. I know so little about large format that I didn't even realize there were external shutters that might be adaptable to the end of many lenses. I'm learning a lot today thanks to Google and this thread.
The Copal #1 shutter has a 30mm iris diameter, the A 50/1.7 front element is also 30mm in diameter. Depending on how close a mount one could manage, vignetting should be fairly minimal with the lens stopped down a little bit. I suspect that by f/4, there should be little if any, and probably easily cropped out by shooting a bit loose.
Not an ideal solution, but the problem being corrected is a relatively rare one as well.

One of these days I might see if I can make my 90mm LS lens work with my K20 as a high sync speed lens, though even if it can be done, the FL is so long that a very powerful flash would be indicated, which would obviate some of the advantage of the high shutter speed.
06-02-2009, 10:28 AM   #175
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or maybe a properly focused flash, rather than powerful? 90mm sounds nice for closer portraits and such (on aps-c).

leaf shutters are not only related to large format. you can get a very cheap one to play with by getting a smena 4m (i think it was called, cmena spelled in russian), it is a sort of rangefinder, and dirt cheap. (it also happens to have been my first camera), it comes with a leaf shutter, in the (non-interchangeable) lens. it is simple and rugged, so you might find it fun to take it apart and see how it works . in this case, the shutter is very close to the apertures blades, so to the optical center of the lens, i guess the main reason is precisely to avoid vignetting (you can get some light loss, but across the frame instead of local, as if stopping down a little, which leads to the discussion about shutter efficiency).

i am not sure how having a leaf shutter so far from the centre of the optical system would work, but i am afraid it would be practically the same thing as having a focal plane shutter (the same issues if you go over the "sync speed", only instead of sliced horizontally or vertically, you have it circular now, like a sort of very hard vignette), unfortunately, if i am not mistaking, the very point of the leaf shutter (also called "central" shutter as opposed to "focal" shutter) is to have it in the centre of the optical system, and that is also what gives it the virtually unlimited sync speed, not it's design in itself (if one would be silly enough to design a vertical travel shutter to work in the optical centre of the lens, you would get the same feature of unlimited sync speed, unfortunately, the opposite is also true: if you take the shutter away from the centre of the lens, you will get a focal shutter (or some freak hyper-focal shutter, or whatever), regardless of the way it uses to block the light, as long as it doesn't block all area at the same time, the sync speed will be limited by the mechanical speed of the shutter.

sorry. (i would be glad to be proven wrong )
06-02-2009, 11:27 AM   #176
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QuoteOriginally posted by Prognathous Quote
When shooting in a quiet place, such a church or a theater, the noise the camera makes directly effects the photographer's ability to "capture an image", so much that using a noisy camera would be forbidden and result in no pictures at all.

Can you give an example where using 1/250 HSS instead of 1/250 X-sync would make the difference between capturing the image and having to give up completely?

Prog.
Disadvantges of HSS vs. full x-sync. speed.

1) Can only use proprietary flash system. Cannot use HSS mode with more powerful mono-head type flashes or less expensive generic flashes such as Vivitar or used Nikon flash on a Pentax camera. Many photogs have a collection of the latter.

2) Proprietary flashes, especially in HSS mode, significantly shorter distance they can be used. This may mean that an umbrella cannot be used because even more light is lost.

Disadvantages of slower sync speed.

1) Some photogs like to take shots of moving subjects that are mostly lit by ambient light, but would like to use some fill flash. If subject is close enough to HSS flash it may work, but it may not. ND filters may help some by increasing the amount of the lighting is from the flash, but this is not fool proof.

2) Most photogs, on occasion, like to use a larger aperture to keep DOF in control while in bright outdoor lighting and would like to reduce the shadow with fill flash. ISO choices do not go low enough (maybe in the future), and slow shutter will not bring shot in desired exposure for background (will be blown out). Quality ND filters would fix this completely, but some photogs do not like to carry them around, or are afraid it will reduce the quality of the image, or believe they are a hassle (especially when you have 3 or more filter sizes for you lenses). This could be a couple hundred dollars in filters or more.
06-02-2009, 11:35 AM   #177
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I was thinking of the diaphragm style leaf shutter, pretty much identical to a lens aperture. The reason it seemed to me that it would cause vignetting is that as the blades open the center is immediately exposed but the edges don't get exposed until the diaphragm is fully open, then the edges are covered again as the diaphragm begins to close but the center continues to be exposed until it is fully closed. I'm sure as I learn more about this the reason that doesn't happen will become clear to me.

I think we are moving this thread further and further from news and rumors with each post. Do we need an new section for hypothetical, theoretical armchair engineered solutions to debatable gear limitations?
06-02-2009, 12:22 PM   #178
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QuoteOriginally posted by Photomy Quote
Disadvantges of HSS vs. full x-sync. speed.

1) Can only use proprietary flash system. Cannot use HSS mode with more powerful mono-head type flashes or less expensive generic flashes such as Vivitar or used Nikon flash on a Pentax camera. Many photogs have a collection of the latter.

2) Proprietary flashes, especially in HSS mode, significantly shorter distance they can be used. This may mean that an umbrella cannot be used because even more light is lost.

Disadvantages of slower sync speed.

1) Some photogs like to take shots of moving subjects that are mostly lit by ambient light, but would like to use some fill flash. If subject is close enough to HSS flash it may work, but it may not. ND filters may help some by increasing the amount of the lighting is from the flash, but this is not fool proof.

2) Most photogs, on occasion, like to use a larger aperture to keep DOF in control while in bright outdoor lighting and would like to reduce the shadow with fill flash. ISO choices do not go low enough (maybe in the future), and slow shutter will not bring shot in desired exposure for background (will be blown out). Quality ND filters would fix this completely, but some photogs do not like to carry them around, or are afraid it will reduce the quality of the image, or believe they are a hassle (especially when you have 3 or more filter sizes for you lenses). This could be a couple hundred dollars in filters or more.
Good summary. A couple of added limitations of HSS:

3) HSS pulses the flash so it is virtually incapable of stopping action. Not only does it radically drop the flash power, which is essential to stopping the action, but each pulse also catches your moving subject at a different spot, often causing more perceived blur than a much slower sync speed.

4) HSS will not work with radio triggers for off camera flash. There are a couple of pricey exceptions now in the Nikon and Canon camps but none for Pentax just yet.

Higher sync speed is not just for fast action either. Its primary purpose for me is to control the ambient light without having to stop my aperture down. It's usually not the moving subject or DOF I'm concerned about, its flash power. The faster your shutter speed, the darker the ambient exposure. The wider the aperture, the more powerful your flash.

I like to shoot into the sun, using it as a free rim or back light, so faster sync is very useful even on posed models. (This was shot Sunday at 1/750 for example) I need to be able to crank up the shutter speed to get that powerful ambient under control and still leave my aperture wide open to catch as much of the limited flash power as possible.

There are countless other ways to control the ambient/ flash lighting (or more accurately environment/ subject lighting) mix, but a faster sync speed is the cleanest and easiest answer pretty much every time.

Last edited by GoldenWreckedAngle; 06-02-2009 at 01:16 PM. Reason: Add a link to example photo
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