First of all, see the tan spots on the background just below your
subject on the right side. I suppose that could be just dirt on the
background paper but it looks to me that it might be dust on your
sensor. It may need cleaning.
On 10/21/2010 6:29 PM, Olaf Greve wrote:
> Hi Chuck and others,
>
> 1) I mounted the brolly boxes on the swivel heads with the flashes; no
> problem. But... the umbrellas are wide and the tripod legs are
> preventing the umbrellas from being angled at some 45 degrees from
> above. I may figure out an easy way around this, but I certainly
> welcome suggestions.
> Either way: this issue caused the umbrellas (and flashes) to be
> shooting perpendicularly from the table top (i.e. from the side of the
> subject, but then positioned higher than the subject, so it's not from
> the very side).
I think I briefly touched on this in our earlier discussions. The flash
unit is probably nearly centered over the tripod. When the brolly box
fits over the flash the brolly is too close to the tripod and the legs
interfere. The flash head must either be raised or extended
horizontally so the brolly can move out farther. I think I had
suggested a piece of aluminum stock about 6x25mm and perhaps 15-20cm
long with a mounting hole on each end. This would allow the flash head
to be moved away from the tripod centerline and also move the brolly
outward the same distance. A trip to your hardware or home supply store
should provide a piece of stock that a hacksaw and drill can fix up with
not much work. As I pointed out before, the brolly boxes are really
made for studio monolights which extend out from the centerline of the
light stand by about the recommended 15-20cm. If you bought the type of
flash adapter bracket you pictured earlier I think the extension bracket
can be gripped in its mini-vise and the T-20 autoconnectors can be
fastened on the other end with 1/4-20 screws.
>
> 2) The daylight was just starting to fade and the location where I was
> taking the pictures was relatively dark. This caused great
> difficulties for the Auto Focus to do its work. The built in flash
> cannot pop up, as the flash shoe cable (T-cord) blocks it. I guess I
> could use an external (small) lamp to make focussing easier, but then
> I'd be throwing incandescent light into the mix. I tried manual
> focussing but that's pretty tough too. I guess I need to shoot during
> the daytime then...
The trick is to remove the autofocus from the shutter button such that
focus and exposure are two separate actions. I forget what model
e-thingy you're using but the instructions to do this are in your user's
manual... some custom setting on your menu system somewhere. Use a
bright light in the room to focus and then turn the light off. There
will be no further need to focus again until you change or move the
target. With the focus control no longer on the shutter button the
camera won't focus again until you press the *new focus button*...
whatever that is after you make the change.
>
> Then, the set-up was:
> E-500 + 14-45 F3.5-5.6, Manual, 1/160 @ f5.6, ISO 100, two T20s, one
> to the left, one to the right of the subject, both firing into the
> brolly boxes, coming straight from the side. Distance from flash to
> diffuser (i.e. round part of the umbrella) +/- 20 cm, distance of
> diffuser to subject +/- 25 cm.
>
> The results are pretty pleasing, but not perfect. If you consider this
> shot (full size, unedited):
> http://www.millennics.com/test/PA215718.JPG
>
> The WB was not yet set properly; in reality, the backdrop is plain
> white.
The color balance isn't too bad once the exposure is increased to reduce
the gray. I think if you just process the image with color balance set
to flash you'll get something that's very close to perfect.
>
> Now, my two main issues with the pictures are:
> 1) Some shadows still occur. This was surprising to me. Perhaps the
> high, perpendicular, position of the flashes relative to the subject,
> caused that? Is this something that can easily be improved (reflector?
> 45 degree angles from above? something else?)
> 2) Another unexpected issue are the two 'gleam' lines running over the
> length of the subject.
>
> To illustrate this, consider:
> http://www.millennics.com/test/PA215718_with_comments.jpg
>
> Could it perhaps be that the light was not diffuse enough?
>
> Any ideas how I can improve this?
Actually, I rather liked the gleam lines. And, while I think the
shadows should be reduced, I don't think they should go away completely.
It will look truly flat if they do. But only you know what you really
want. Diffusion and exposure will increase if you can get the flashes
even closer. To kill residual shadows you need to place some reflectors
around on the side where the offending shadows are. I think I suggested
some pieces of foam core board from the local craft shop. Large pieces
in white can be had for $1-2. A sharp knife and some tape or a glue gun
to attach foam core support pieces to the foam core reflectors should
get what you want.
If you can't get the exposure up by moving the lights closer you may
have to up the ISO. I assume you can go as high as ISO 400 without any
significant degradation of the image.
>
> Cheers,
> Olafo
Cheers,
Chuck Norcutt
--
_________________________________________________________________
Options: http://lists.thomasclausen.net/mailman/listinfo/olympus
Archives: http://lists.thomasclausen.net/mailman/private/olympus/
Themed Olympus Photo Exhibition: http://www.tope.nl/
|
