fill flash on bright day


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woah ho! ISO200?? :sweat: flash sync at 1/180..:sweat:
spot meter ur background to get a rough estimate of aperture to use..

hmm.. even the higher end pentax k10 has Flash sync speed: 1/180 sec, lowest iso 100... am i reading the specs wrong or is pentax that poor in flash?
 

very simple, just tell your D70/D70s that you are not using Nikon Flash, than you can sync all the way to 1/8000s, of course Nikon will not tell you this will work.

In fact no need to sync beyond 1/2000 unless you need super fast recycling... Full power output takes about 1/800, half power 1/1600, quarter power 1/3200. :D You can already overpower the sun with SB600.

But you need to work in manual flash mode, which is easy on digital anyway.
 

hmm.. even the higher end pentax k10 has Flash sync speed: 1/180 sec, lowest iso 100... am i reading the specs wrong or is pentax that poor in flash?

K10 is not really high-end ... 1/180 is probably due to the in-body AS, without which it may do 1/200.

The super high sync speed on D70/D40 is due to the electronic shutter (CCD shutter) used. The mechanical shutter on D70 syncs at something around 1/125 (1/90 on N70 but D70 has 1.5x crop).
 

In fact no need to sync beyond 1/2000 unless you need super fast recycling... Full power output takes about 1/800, half power 1/1600, quarter power 1/3200. :D You can already overpower the sun with SB600.

But you need to work in manual flash mode, which is easy on digital anyway.
Why sync beyond 1/2000s will give you faster recycling?:dunno: Flash power has nothing to do with sync speed.

A classic case that someone will need flash with high speed sync is when you need to use fill-in flash in bright environment and yet still want to use large aperture for shallow DOF. When you have large aperture in bright environment, your shutter speed have to go up for proper exposure, unless you use ND filters to keep the shutter speed within the normal sync speed.

BC
 

K10 is not really high-end ... 1/180 is probably due to the in-body AS, without which it may do 1/200.

The super high sync speed on D70/D40 is due to the electronic shutter (CCD shutter) used. The mechanical shutter on D70 syncs at something around 1/125 (1/90 on N70 but D70 has 1.5x crop).

so what can i do to have proper fill flash with the limitation of 1/180?
 

so what can i do to have proper fill flash with the limitation of 1/180?
If the scene is too bright that you have to use shutter speed faster than 1/180s, use a ND filter to bring down the shutter speed.

Pentax cameras do not have high speed sync features? I thought they do.

BC
 

If the scene is too bright that you have to use shutter speed faster than 1/180s, use a ND filter to bring down the shutter speed.

Pentax cameras do not have high speed sync features? I thought they do.

BC

maybe it's a P-TTL thingy :dunno: ... i know nuts about flash...

found an article, which suggested setting -1.7 compensation

http://photo.net/bboard/q-and-a-fetch-msg?msg_id=00K0O8

P-TTL works much better for closer stuff. I think manual works pretty well for far off stuff.

P-TTL also works great for fill. -1.7 comp usually does the job for natural looking fill (shooting fairly close to the subject 5-20ft).

Not sure if you gain anything, I'd gladly trade P-TTL for a higher native X sync.
 

so what can i do to have proper fill flash with the limitation of 1/180?
on a bright sunny day, your minimum iso is 200, max sync speed is 1/180s, you you lens aperture is around f16 1/2, I have no idea of what pentex p-ttl do, but you can set to P mode and let the camera take care about the rest, or use S mode to set speed at 1/180s, and let the camera take care of f stops.
 

on a bright sunny day, your minimum iso is 200, max sync speed is 1/180s, you you lens aperture is around f16 1/2, I have no idea of what pentex p-ttl do, but you can set to P mode and let the camera take care about the rest, or use S mode to set speed at 1/180s, and let the camera take care of f stops.

i did use p mode, but the camera is over exposing my shots... maybe i'll try to set the speed to 1/180s r compensate the flash by -1.7 and see how things goes...

thanks guys for your help!
 

i did use p mode, but the camera is over exposing my shots... maybe i'll try to set the speed to 1/180s r compensate the flash by -1.7 and see how things goes...

thanks guys for your help!
it shouldn't be, the camera should know a flash attach and will no go beyond 180/s, unless you have override it in the camera setting.
 

it shouldn't be, the camera should know a flash attach and will no go beyond 180/s, unless you have override it in the camera setting.

i am using the in camera flash, so it should know what it is doing in p-mode but it didn't
 

i am using the in camera flash, so it should know what it is doing in p-mode but it didn't

I don't think the built-in flash can do FP flash...:sweat:
 

i did use p mode, but the camera is over exposing my shots... maybe i'll try to set the speed to 1/180s r compensate the flash by -1.7 and see how things goes...

thanks guys for your help!
When you say overexpose, is the whole scene overexposed or just the flash overexposing the subject?

BC
 

the subject is over exposed

In that case, shutter speed may not be the problem. Flash compensation may help.

When you are using flash, try shooting in M mode. Meter the scene manually, leave the flash to adjust itself via TTL (with the appropriate flash exposure compensation). You'll have more control on the overall exposure.

BC
 

Why sync beyond 1/2000s will give you faster recycling?:dunno: Flash power has nothing to do with sync speed.

A classic case that someone will need flash with high speed sync is when you need to use fill-in flash in bright environment and yet still want to use large aperture for shallow DOF. When you have large aperture in bright environment, your shutter speed have to go up for proper exposure, unless you use ND filters to keep the shutter speed within the normal sync speed.

BC

Flash has a duration. Normally a good flash's full output takes about 1ms, so 1/1000 is the limit to record a full flash output. At 1/2000, half of the flash output will be after the shutter has been closed. Given a fixed ambient-flash lighting ratio, above 1/1000, the faster the shutter speed, the lower the flash output is required.

Say for example the ambient is metered ISO 100, F/8, 1/1000 and you would like to fill in with a full flash output - you can dial to F/5.6 1/2000 and half flash output instead. Since the capacitor is only half-discharged, the next shot will be ready sooner.
 

what is a FP flash?

Focal plane (FP) flash. Instead of a single pulse of flash (<= 1ms), the strobe maintains a lower output level for a longer time (appx. 5ms).

When shooting above the sync speed, the film is not exposed entirely at any instance of time, only a slit is open for light and the slit travels vertically. FP flash keeps a constant illumination for this slit to run across the film.
 

In that case, shutter speed may not be the problem. Flash compensation may help.

When you are using flash, try shooting in M mode. Meter the scene manually, leave the flash to adjust itself via TTL (with the appropriate flash exposure compensation). You'll have more control on the overall exposure.

BC

I think he's getting overexposure because the camera enforces the X-sync speed instead of the metered speed.

lizzy -
Get either AF360 or AF540 for the so-called high speed sync (FP), alternatively, as others have suggested, get an ND filter.
 

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