1/200 sec flash x-sync on 5D

In message ,
"Steve Wolfe" wrote:

Why are you concerned over a quarter of a stop? If you have anything that
1/200 won't do for you, 1/250 probably isn't going to cut it, either.

What if the difference is right on the border of action-stopping or
hand-holdability? The difference can be visible.
--


John P Sheehy

"J Miro" wrote:

I am about to purchased a DSLR camera and some high quality lenses. I am
seriously considering Canon EOS 5D because it offers most of the features I
need for studio/portraiture photography. However, the 1/200 sec x-sync (vs.
1/250 on 20D and 1D series cameras) concerns me. I have been told that this
means I will be limited to shutter speeds of 1/200 sec or slower when using
non-Canon strobes and professional studio power packs. Is this true? If so,
I would like to ask the professionals out there whether this is limiting in
studio photography (or in general) and if there is a solution. If you were
in my position, would you pick the new 1D Mark II N over 5D because of this
limitation? Thanks in advance.


In the studio a 1/200 synch speed isn't a limitation at all.

It only becomes limiting outdoors in daylight when you are using
daylight balanced fill flash. Even then, the small difference between
1/200 and 1/250 sec is not going to make a significant difference.

What if the difference is right on the border of action-stopping or
hand-holdability? The difference can be visible.

The OP was talking about studio work. When using flash in the studio the
shutter speed doesn't make any difference. It only makes a difference
when balancing ambient light with flash, and in that case if he has the
money for a 5D then he could probably afford a Canon strobe which
eliminates that problem as well.

It also reduces the "action-stopping" capability of the flash to the
shutter speed, whereas the flash could be as short as 1/10,000 with
normal sync, with high ISOs and/or close subjects.

In other words, switch the shutter speed from 1/200 to 1/320, and the
shortest flash duration possible drops from 1/10,000 to 1/320, and it
also exposes different parts of the frame at different times, which can
create artifacts, when the shutter speed is 1/320.

This is one of my biggest problems with my gear; I like to shoot birds
from close range in moderately dark conditions, and like to use about 30
- 40% flash for the exposures, but I use 560mm on a 1.6x crop with IS,
and I really need a shutter speed of at least 1/320, but am forced to
use 1/250 (20D max sync) to get a truly punctuating flash.

Ah yes, that makes sense. I wasn't sure what you meant there for a bit,
but then I remembered that in high speed sync mode the flash pulses for
the full duration of the exposure. I can understand how in certain
situations that would result in a different effect. That's one of those
situations that I hadn't thought of, but still this wouldn't be a
problem when working in a studio.

In message ,
Eugene wrote:


Ah yes, that makes sense. I wasn't sure what you meant there for a bit,
but then I remembered that in high speed sync mode the flash pulses for
the full duration of the exposure.

Which, of course, is longer than the stated time, looking at the frame
as a whole; it is only the individual pixels that are exposed for that
time; one end of the frame is exposed before the other.

I can understand how in certain
situations that would result in a different effect. That's one of those
situations that I hadn't thought of, but still this wouldn't be a
problem when working in a studio.

I like to think of high-speed sync as auxilliary lighting that is only
lit when the shutter is open. That gets right to the bottom line, and
avoids any confusion.
--


John P Sheehy

I like to think of high-speed sync as auxilliary lighting that is only
lit when the shutter is open. That gets right to the bottom line, and
avoids any confusion.

Just out of curiosity. What happens when the flash is in high-speed sync
mode but the shutter speed is at (or longer than) the sync speed? Does
it automatically change back to normal mode, or would it still do the
pulsing thing? I often just leave the flash in high-speed mode, so that
I don't have to worry about forgetting to switch it on when I'm using
fill in bright sunlight.

"J Miro" wrote in message
...
I am about to purchased a DSLR camera and some high quality lenses. I am
seriously considering Canon EOS 5D because it offers most of the features I
need for studio/portraiture photography. However, the 1/200 sec x-sync (vs.
1/250 on 20D and 1D series cameras) concerns me. I have been told that this
means I will be limited to shutter speeds of 1/200 sec or slower when using
non-Canon strobes and professional studio power packs. Is this true? If so,
I would like to ask the professionals out there whether this is limiting in
studio photography (or in general) and if there is a solution. If you were
in my position, would you pick the new 1D Mark II N over 5D because of this
limitation? Thanks in advance.



Jay

Yes it's true but it's not a problem unless you're hand-holding a 1000mm
lens! ; )
Usually in the studio the burst of flash is solely responsible for the
complete exposure. This burst (depends on the model) will have a duration of
something like 1/700 to 1/1400 of a second. So there's really no issue at.
Your camera will be in manual mode, your aperture selected within the
'confines' of the flash output, and the sync shutter speed really doesn't
matter unless ambient light is very bright. Some time ago 1/125 sync was the
norm.
Sync speed does matter when you're using both flash and ambient light to
make your exposures. If your studio has good daylight available (and you
want to use it with flash) then you have an issue. To be honest though the
difference between the two models sync speeds is negligible.
Both the 1D mkII and the 5D are fine for the studio. I'd personally choose a
5D as its extra resolution opens up more markets to sell to
--
Simon
http://www.pbase.com/stanmore

In article Eugene writes:
$Just out of curiosity. What happens when the flash is in high-speed sync
$mode but the shutter speed is at (or longer than) the sync speed? Does
$it automatically change back to normal mode

Yes. The switch *enables* high-speed sync mode; it doesn't *select*
it. If you turn off the switch, you don't get high-speed sync, and
the body will limit the shutter speed to maximum X-sync. If you turn
on the switch, you get normal flash at max X-sync or below, and high-
speed sync above that.

$ I often just leave the flash in high-speed mode, so that
$I don't have to worry about forgetting to switch it on when I'm using
$fill in bright sunlight.

I do the same, and have had no problems with doing this on a 380EX
with an Elan II, or with a 420EX on an Elan 7E and now on a 20D.
--
Stephen M. Dunn
---------------- http://www.stevedunn.ca/ ----------------
------------------------------------------------------------------
Say hi to my cat -- http://www.stevedunn.ca/photos/toby/

In message ,
Eugene wrote:

I like to think of high-speed sync as auxilliary lighting that is only
lit when the shutter is open. That gets right to the bottom line, and
avoids any confusion.

Just out of curiosity. What happens when the flash is in high-speed sync
mode but the shutter speed is at (or longer than) the sync speed? Does
it automatically change back to normal mode, or would it still do the
pulsing thing? I often just leave the flash in high-speed mode, so that
I don't have to worry about forgetting to switch it on when I'm using
fill in bright sunlight.

The system doesn't use high-speed sync unless it really needs it. If
you leave it on, though, the shutter speed won't change to the max sync
speed when you turn the flash on.

Let's say you manually set the Tv to 1/320; with high speed sync
enabled, it will stay at 1/320; if you have it disabled it will go to
1/250 (20D) when you turn the flash on.
--


John P Sheehy

On 2005-10-23 18:56:09 -0400, "J Miro" said:

I am about to purchased a DSLR camera and some high quality lenses. I
am seriously considering Canon EOS 5D because it offers most of the
features I need for studio/portraiture photography. However, the 1/200
sec x-sync (vs. 1/250 on 20D and 1D series cameras) concerns me. I have
been told that this means I will be limited to shutter speeds of 1/200
sec or slower when using non-Canon strobes and professional studio
power packs. Is this true? If so, I would like to ask the professionals
out there whether this is limiting in studio photography (or in
general) and if there is a solution. If you were in my position, would
you pick the new 1D Mark II N over 5D because of this limitation?
Thanks in advance.



Jay

I am not a pro.. but why on earth in a studio with controlled light
would you care? The exposure time is controlled by the flash duration
which is measured in x/1000's of a second. The time your shutter is
open has little effect, in fact probably NO effect on the exposure.
The only advantage to high shutter speed flash sync is when outdoors
using fill flash etc where you are merely supplementing the ambient
light. In a studip, unless you are doing some cool stuff with natural
window light and flash, the flash is the exposure.


--
Jim