Re: Underwater Digital Camera recommendations

> Get the Sony 7MP (DSC-P150) and their housing. The total should be
> right in the $600 range if you buy right.

Are you able to use an external strobe with this set-up?

In article <Xns95DC69A8F73CDbobengrhotmailcom@207.115.63.158> ,
bob <bobengr@hotmail.com> wrote:
>
>> Get the Sony 7MP (DSC-P150) and their housing. The total should be
>> right in the $600 range if you buy right.
>
>Are you able to use an external strobe with this set-up?

Yes, if you optically slave it (that is, the flash fires based on the
on-camera's "flash"). There is no TTL port available with it - or
with any other "compact" point and shoot camera, however.

To get a sync output you need to go to something like an Oly 5050 and Ike
housing which is both significantly larger and more expensive.

--
--
Karl Denninger (karl@denninger.net) Internet Consultant & Kids Rights Activist
http://www.denninger.net My home on the net - links to everything I do!
http://scubaforum.org Your UNCENSORED place to talk about DIVING!
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"Dan Bracuk" <NOTbracuk@pathcom.com> wrote in message
news:3c79u0dc06kon52fvjrv2r0t8nt2t7cihk@4ax.com...
> "ben bradlee" <up2u2figr@NoWay.zip> pounded away at his keyboard
> resulting in:
> :You have nice pictures Dan. The Sony pictures exhibit an eerie clarity. Is
> :that from reducing the file size? What file did you use for the web? The
> ictures load instantly.
>
> Thank you for the compliment. Since many people I know, Mom for
> instance, still have dial up connections, I try to minimize
> downloading time. I try to send images no larger than 60 KBytes to
> the web.
>
> To achieve a 60 Kbyte file, I do this. With my new 4 MPixel camera,
> files go from the camera to computer as jpg's roughly 1.7 Mbytes in
> size. I immediately save them to tiff, which expands them to about 15
> Mbytes. Subsequent editing results in a tiff file anywhere from 5 to
> 16 Mbytes large, depending on what I did. These are the files I
> print.

Why do you expand the file. You get no more detail and are you not just wasting
memory?

Adam



>
> Note that with my 1.3 Reefmaster, the files are roughly one quarter
> the size.
>
> If I want to put one of these images on the web, I save back to jpg.
> I give it a width of 600 pixels and compress it by a factor ranging
> from 20 to 50, whatever it takes to produce a file of about 60 Kbytes.
>
> Sometimes this last step results in image deterioration. For example,
> look at the background water in this shot.
> http://www.pathcom.com/~bracuk/under...llowSponge.htm. Notice
> how the colour sort of changes. That only happens after the final
> conversion of tiff back to jpg, and only when I really compress the
> image.
>
> Dan Bracuk
> If we don't succeed, we run the risk of failure.

In message <9TbFd.26608$jn.4945@lakeread06>, Karl Denninger
<karl@FS.Denninger.Net> writes
>Yes, if you optically slave it (that is, the flash fires based on the
>on-camera's "flash").

What do you need to do this? I have a Sea & Sea TTL Strobe - could this
be made to work on a point & shoot like a Canon ixus, (IXY SD500).

--
Richard Faulkner

In article <Th4zRwFreY5BFw3X@estate.demon.co.uk>,
Richard Faulkner <richard@estate.demon.co.uk> wrote:
>
>
>In message <9TbFd.26608$jn.4945@lakeread06>, Karl Denninger
><karl@FS.Denninger.Net> writes
>>Yes, if you optically slave it (that is, the flash fires based on the
>>on-camera's "flash").
>
>What do you need to do this? I have a Sea & Sea TTL Strobe - could this
>be made to work on a point & shoot like a Canon ixus, (IXY SD500).
>
>--
>Richard Faulkner

Just a strobe that knows how to optically slave. Most do, but not all,
because even if you TTL fire one of them, you almost never are able to slave
the second off the first (except optically.)

--
--
Karl Denninger (karl@denninger.net) Internet Consultant & Kids Rights Activist
http://www.denninger.net My home on the net - links to everything I do!
http://scubaforum.org Your UNCENSORED place to talk about DIVING!
http://www.spamcuda.net SPAM FREE mailboxes - FREE FOR A LIMITED TIME!
http://genesis3.blogspot.com Musings Of A Sentient Mind

"Adam Helberg" <sendspamhere@yahoo.com> pounded away at his keyboard
resulting in:
:Why do you expand the file. You get no more detail and are you not just wasting
:memory?

I read somewhere that everytime you save a jpg file, it compresses a
bit and gets a bit worse. When editing my photos, I will save the
file up to a dozen times as I go along.

Reef Fish, (Large Nassau Grouper), who frequents the rec.scuba ng
pointed the article out to me. He might know where to find it, I
don't.

What I read could be wrong, but I believe it. Plus, my pc has ample
memory and hard drive space so it does not matter if I waste a byte or
two.

Dan Bracuk
If we don't succeed, we run the risk of failure.

"ben bradlee" <up2u2figr@NoWay.zip> pounded away at his keyboard
resulting in:
:I realized from looking at your photos that I've incorrectly named fish.

What makes you so sure I was the one who was right?

Dan Bracuk
If we don't succeed, we run the risk of failure.

Richard Faulkner wrote:

>> Yes, if you optically slave it (that is, the flash fires based on the
>> on-camera's "flash").
>
>
> What do you need to do this? I have a Sea & Sea TTL Strobe - could this
> be made to work on a point & shoot like a Canon ixus, (IXY SD500).

If the Sea & Sea strobe has a built-in slave sensor it will fire when the flash on
the camera fires. Since the ixus is digital, though, it probably has a pre-flash,
which means the flash will fire when the camera is checking focus and exposure, and
not when the camera is actually taking the picture, unless the strobe is designed for
digital cameras. For a digital camera that has pre-flash you need a slave sensor that
is designed to ignore the pre-flash and fire on the main flash. Ikelite offers two
slaves that will do that, for about $150 each. Look here, and scroll down a bit:
http://www.ikelite.com/web_pages/sync_cords.html

The TTL slave sensor uses the camera's flash duration to control the external flash,
and the manual controller offers you 10 power settings and can be triggered with a
sync cord (when the camera and housing are compatible with it) or its built-in slave.
The catch is that they only work with Ikelite's new digital strobes, which will set
you back at least $300. You can get a package with the smaller strobe, sensor and a
strobe arm for about $500 and change.

Be aware that the slave sensor may not give you the full power of an external strobe.
If the flash duration of the on-camera strobe is too short the external strobe may
not reach maximum output before being quenched. For some cameras Ikelite will suggest
the manual controller for that reason.




--
Steve

The above can be construed as personal opinion in the absence of a reasonable
belief that it was intended as a statement of fact.

If you want a reply to reach me, remove the SPAMTRAP from the address.

If you are going to use an external flash on a digital camera using it as a
slave unit, it must have three additional functions:

1. It must have a slave sensor that can trigger the flash from an external
flash. For reliable operation you may need a fibre-optic cable kit to
ensure that it will still trigger even when not pointed directly at the
cameras built-in flash unit.

2. It must be compatible with the pre-flash given out by many digital
cameras, otherwise it will 'flash' when the internal camera does it's
pre-flash, not when the main exposure flash is triggered.

3. You will need a variable flash power setting so you can manually set the
external flash to suit the distance between you and the subject, aperture
and ISO (ASA) setting. In addition this can also be useful when balancing
flash against ambient light, as when photographing a close-up whist not
losing detail in the background.

Many UW flashes have these functions. I use the Sea&Sea YS90TTLdx Duo, the
YS120dx also has these functions. Ikelite, Subtronic, Epoque and Inon also
of these functions on some of their models.

The Inon are getting very good reviews over here in the UK.

"Dan Bracuk" <NOTbracuk@pathcom.com> wrote in message
news:6vobu09onpjgqiumgsvg6v5q8ih5cus9ae@4ax.com...
> "ben bradlee" <up2u2figr@NoWay.zip> pounded away at his keyboard
> resulting in:
> :I realized from looking at your photos that I've incorrectly named fish.
>
> What makes you so sure I was the one who was right?

I saw it on my computer screen - it has to be right )