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08-09-2015, 10:51 AM - 2 Likes   #46
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I want to apologize to all for my incorrect information. I was not right that the aperture effects only flash exposure. Thank you for correcting me and forcing me to research my information. You all just did your part in making me a better informed and consistent photographer. That is the number one reason I joined this forum. Thanks

08-10-2015, 05:16 AM - 1 Like   #47
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Hey, don't worry ....Its only by stating things we believe directly that points can be identified and picked up. I never worry about being wrong .... Not being sure of something and showing it is the start of more interesting discussion and encourages others to join in!
09-09-2015, 06:30 PM - 1 Like   #48
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QuoteOriginally posted by fredralphfred Quote
The thing I don't understand is why a camera can't have a leaf shutter built-in, but nobody seems to do it.
I am guessing you have noticed that the aperture blades are also between lens elements in a camera? In fact they sit at a point where light rays 'cross over' to create an inverse image on the sensor. If placed anywhere else, the smaller aperture would just block part of the image, as opposed to reducing the level of light transiting the lens.

A leaf shutter placed at this same point can be much smaller - meaning much less mass and finally, less power needed to move the leaves to the full width of the aperture for a given shutter speed. if you placed the leaf shutter inside the camera body, it would have to be the same size as the sensor - - - and for something that big, the best mechanical approach is the focal plane shutter.
09-09-2015, 08:44 PM   #49
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QuoteOriginally posted by BrianR Quote
For me it's mostly working outdoors combining sunlight with flashes where the aperture and iso end up with little leeway to stay under the sync speed. It's much better now that I have a k5iis with iso 80 compared to my old k100d which bottomed out at iso200 (as Class A points out, iso 80 is very handy to have!). I also usually have the luxury of having flash power to spare, so dropping the iso (or nd filters) can work for me (but this isn't the case for everyone). This doesn't mean I wouldn't make use of 1/1250th if it were available though.
I'm often in a similar situation, except I use speedlights and don't have the power to spare. 1/250 would help me darken my background relative to my [lit] subject that little bit more.

09-09-2015, 11:28 PM   #50
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QuoteOriginally posted by skunktail Quote
1/250 would help me darken my background relative to my [lit] subject that little bit more.
Using ISO 80 instead of ISO 100 gets you almost the same kind of exposure decrease. Many cameras cannot go there so for K-5 (II)(s) cameras the 1/180s limit isn't quite as limiting as it initially sounds.
09-09-2015, 11:51 PM   #51
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wouldn't a more powerful flash and an ND-filter achieve the same thing?
09-10-2015, 04:41 AM   #52
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It would but some don't want to go down the ND path.

I don't see the fuss over the approx. 2/3 stop difference vs 1/250. Now if it was compared to 1/360 or 1/500 then it becomes more light and day.

Of course, if 1/250 was offered I'd take it.
09-10-2015, 04:41 AM   #53
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QuoteOriginally posted by Bromberger Quote
wouldn't a more powerful flash and an ND-filter achieve the same thing?
This has the same effect on the relative exposure of flash vs ambient as a faster shutter speed, yes, and would be equivalent to having a lower iso available (though not as convenient- iso 80 really is nice*).

However, an ND filter is no help vs. camera shake or subject movement if the ambient is a contributing factor in your exposure. 1/180th is often in the fringe of where I'm comfortable hand holding, so having a bit more shutter speed available would be nice to cut down on ghosting (think subject lit by flash, background by ambient).


*Would anyone say no to having iso50 avaiable?

09-10-2015, 05:13 AM   #54
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QuoteOriginally posted by BrianR Quote
an ND filter is no help vs. camera shake or subject movement if the ambient is a contributing factor in your exposure.
oh i see. didn't realise that, thank you.
09-10-2015, 02:40 PM   #55
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QuoteOriginally posted by Class A Quote
Using ISO 80 instead of ISO 100 gets you almost the same kind of exposure decrease. Many cameras cannot go there so for K-5 (II)(s) cameras the 1/180s limit isn't quite as limiting as it initially sounds.
I'm not denying this for a second. I use ISO 80 all the time.
But when I'm fighting australian midday sun with speedlights, I'll take all the help I can get.
09-10-2015, 07:10 PM   #56
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QuoteOriginally posted by Class A Quote
I'd rather take the ISO 80 than a sync-speed of 1/250s.
I agree. A lower ISO, like ISO15 or 25 would be even better.

This is what 1/500th flash sync looks like on a K5IIs:


Last edited by Digitalis; 09-10-2015 at 07:17 PM.
09-11-2015, 09:27 AM   #57
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QuoteOriginally posted by shaolen Quote
so many of the posts are saying "why would you need this" and the reason is moving subjects. For sports and action 1/180 is going to still have some motion blur while 1/250 has a better chance at stopping the action. I first noticed this issue when showing my K-5 to a friend who shoots sports with Canon gear and when he saw the 1/180 sync he immediately went "whoa, that's a bit too slow for what I do". Until that point he was absolutely loving the camera but that's one lost customer and I'm sure theres many many more like him.[COLOR="Silver"]
So I don't think your friend is aware what he's doing
A few thoughts

Under flash the flash time freezes the action not the shutter so 1/10 , 1/180 or 1/250 make no odds the athlete is frozen by the flash not the shutter.

If hes deliberately attempting 'fill' flash (probably because hes an amateur and forced to shoot from the spectator stands so has contra jour etc to contend with) then irrelevant of the flash he's going to need 1/400 to freeze the average 'sports' action so again 1/180 or 1/250 wont help

Those sports where you can get down to 1/200 ball park (breast stroke swimming for example) it makes no odds whether your shooting 1/180 or 1/250.

So in summary in most sports/action in ambient light
1/180 will have motion blur
1/250 will have motion blur
at least 1/400 will be required

Under flash
Shutter irrelevant

So to use flash for fill use in sports you need HSS and enough flashes to deliver the power you require anytime your using a dlsr type shutter be it Nikon , Canon or Pentax.

Even to take decent flash only shots you need multiple flashes rather than a faster shutter.
09-22-2015, 01:55 PM   #58
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QuoteOriginally posted by Digitalis Quote
I agree. A lower ISO, like ISO15 or 25 would be even better.

This is what 1/500th flash sync looks like on a K5IIs:
Can you please explain how you did this? There are cases where I would be happy to crop out the black bar if I could just get the flash to fire at faster than 1/180th.
09-22-2015, 06:36 PM   #59
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QuoteOriginally posted by jake14mw Quote
Can you please explain how you did this? There are cases where I would be happy to crop out the black bar if I could just get the flash to fire at faster than 1/180th.
I synchronized the shutter of my Nikon D4 and K5IIs to fire at the same time. After that, it was a simple matter to use the D4 to fire a flash at a white reflector and see how badly the shutter curtains occluded the sensor on the K5IIs at 1/500th shutter speed.

I would rather have a D4 with its faster 1/250th sync speed and fast Nikkor telephoto glass than to waste time cropping out black bars.
09-22-2015, 06:57 PM   #60
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QuoteOriginally posted by jake14mw Quote
There are cases where I would be happy to crop out the black bar if I could just get the flash to fire at faster than 1/180th.
There are alternatives to how Digitalis did it:
  1. You can use an HSS-capable flash as a trigger signal generator and either use manual flashes to trigger on the main flash (pre-flash trigger suppression)) -- that works up to 1/2000s -- or use a Cactus V6 to trigger on the pre-flash and delay the triggering of the remote flash(es).
  2. You can use a trigger supporting delays to trigger the camera and flash at the "same" time.
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