How to capture Max DOF (infinity) and use Fill Flash

[jcuknz]

If you have a Guide Number of 80 then to use f/16 the subject needs to be at five feet and not ten feet. That is basic flash practice. 80/16 = 5 Though as a syncro-sunlight fill I would have thought the result better with subject at 7'6".
.

Note. DoFMaster tells me that with a 28mm lens focus at 10 feet you have DoF from 4.48feet to infinity ...
so bringing subject in to five feet would have been permissable and you don't need that P&S

Edit some days later ... sorry I got confused and thought you had the 28mm lense but even with the 35mm focused at 12 ft the subject at 7.5ft should have been sharp though of course this depends on how large you aimed to enlarge to and at what distance it was viewed from.
Further edit ...Puzzled by examples which do not match Dennis's requirement that the background be sharp. In suggesting the 12ft focus distance I am assuming that anything beyond around 200ft will not be noticed as soft so even my answer doesn't really give Dennis the solution if one is hyper critical.

[DeKa77]

FlashTech !



Same same situation and it is shot as following :

D 90 + expo180 + aper f8 + focal 35mm + Iso 200 + FlashTech ( only one flash fixed on the body )

[Colin Southern]

FlashTech !



Same same situation and it is shot as following :

D 90 + expo180 + aper f8 + focal 35mm + Iso 200 + FlashTech ( only one flash fixed on the body )

Hi,

Hice shot, but don't forget to point the flash up a little to feather the output and prevent it over-exposing the foreground (or zoom the flash head more) (I've knocked it back 2 stops with a digital GND here) ...

[DeKa77]

Tks for yr retouch. The weak point of this flashtech that we called flashdown is the lower part of the subject is often a little overexposure and we are trying to overcome this, as following :

[Colin Southern]

Tks for yr retouch. The weak point of this flashtech that we called flashdown is the lower part of the subject is often a little overexposure and we are trying to overcome this, as following :

Normal (post-processing) work-around is to apply a digital GND to balance the lighting, and then a vignette to give the illusion of perfectly targeted lighting ...

[William W]

In the first image sample the Subject's: Left Knee, Left Shin and Left Foot (skin); and Left Thigh (Dress); and Front of Left Elbow (skin) are all illuminated by direct sun.

Are they not?

WW

[DeKa77]

In the first image sample the Subject's: Left Knee, Left Shin and Left Foot (skin); and Left Thigh (Dress); and Front of Left Elbow (skin) are all illuminated by direct sun.

Are they not?

WW

Tks and I think so . We are trying to get to the peak of FlashTech - you hardly find the flash reflect except the catchlight in the eyes and trying to narrow it.

[DeKa77]

Overexposure or Sunlight !



FYI, it's taken at noontime.
D 90 + epo 90 + ape f8 + 70 mm + Iso 200 + FlashTech (the distance to apply FT is to depend on the focal length - so 40-45cm is also OK. )

[Colin Southern]

In the first image sample the Subject's: Left Knee, Left Shin and Left Foot (skin); and Left Thigh (Dress); and Front of Left Elbow (skin) are all illuminated by direct sun.

Are they not?

WW

Probably, although I suspect it was a bit of both.

At the time, I would have used a diffuser (or repositioned the subject). In PP I would have applied a digital GND as well though.

[William W]

Overexposure or Sunlight !

BOTH.
It is very likely overexposed areas of the frame (specifically the spot on Forehead and top Left Breast and Left Shoulder)as a result of being illuminated by direct sunlight.

This was one of the points I was making in Post #26.

Specifically:
If your text is interpreted correctly, the first of these three images was shot at:
F/8 @ 1/180s @ ISO200.

It appears there is direct sun on the areas specified - the shin foot and thigh.

If both these assumptions are fact and the shot was made between about 0900 and 1600, then depending upon the latitude of the location, those areas lit by direct sunlight are approximately 1⅔ to 2⅓ stops over exposed by the sunlight, irrespective of any effect by the flash.

***


Similarly in shot three, it is mentioned that the image was made at midday.

If the exposure specs were: F/8 @ 1/90s @ ISO200, then the areas of skin illuminated by the direct sun are about 3 stops over exposed.


WW

[DeKa77]

Thank Bill. Your C&C help me a lot !

[DeKa77]

FYI : F/5.6 @ 1/125s @ ISO200 @ FlashTech

[William W]

Dennis, DeKa77,

When using Flash as Fill In Sunlight:

> If you want your flash to be as powerful as possible as a Fill in Sunlight, in relation to the sunlight and,
> Also to have the broadest range of useful Fill Light (Flash) to Key Light (Sunlight) Ratios,

Then you should set the shutter speed to the x-sync speed of the Camera and work your Ambient and Flash Expoures from that base.

I believe for a D90 that the Max Flash Sync is 1/200s; the same 1/200s is the Max Sync Shutter Speed for a D5100 as I understand.

I thought I had and I had intended to mentioned this before: but it appears I didn’t.

WW

[Colin Southern]

FYI : F/5.6 @ 1/125s @ ISO200 @ FlashTech

Looking good in terms of exposure - levels - colour balance - processing. The only thing I'd change is the crop - IMO there's too much space above the head that not contributing anything to the image (and a little behind the lady also).

[DeKa77]

Thank Colin Southern for the crop, it made our pic better.
Also, tks to Bill . FYI,acctually, the max flash sync of D90 is 1/250s, but the above pic is set at 1/125s in order to have DoF to Infinity !

[DeKa77]

FYI : F/8 @ 1/250s ( this made the backgound blur ) @ 50mm @ Flashdown.
Flashdown is a tech of FlashTech in which the flash is adjust down to the ground and it reflects to the subject. And we think this Tech can apply to Dennis' - the beach sand is wonderful soft reflector in this scenario !

[William W]

FYI,acctually, the max flash sync of D90 is 1/250s, but the above pic is set at 1/125s in order to have DoF to Infinity !

Page 268 of my Nikon D90 User Manual says 1/200s is the Max Flash Sync Speed, so I believed that to be correct.

I do not believe that the image above which was shot at Shutter Speed 1/125s, has DoF to infinity – the background is definitively Out of Focus, in my opinion.

WW

[DeKa77]

Thank Billl, I agree with yr opinion and wonder if we set at 1/30s or 1/15s instead of 1/125s , the DoF may be to infinity ? Or F to F/11 @ F/16 ?

[jcuknz]

I could have sworn I added an apology to the OP for suggesting a 28mm lens instead of the 35mm he told us quite clearly he had ... the revised info from dofmaster gave a DoF from 6.nnft through to 224ft at f/16 when focused at 12ft. If the 'subject was at 7.5 feet I'd hope the softening beyond 225ft would not be noticeable so that is how the OP could have achieved his sharp background.

[DeKa77]

We suggest this can help to apply for Dennis' scenario.
FYI : 1/180s @ F/5.6 ( kit 18-55 ) @ 23mm @ ISO 200 @ FlashTech ( Focal length may be not in effect )