Photographing birds in flight

M-M wrote:
In article ,
"Roger N. Clark (change username to rnclark)"
wrote:

There should be no exif
data as the jpegs are stripped to reduce size.

You remove the EXIF purposely to reduce the size, or reducing the size
removes the EXIF?

For web images I use photoshop's save for web function.
It strips out all the extraneous header info to reduce
the byte count of the image. Smaller image size in bytes =
faster download times. I have started turning on the ICC
profile so ICC data are included in my newer images.
That increases file size by only a few tens of bytes.

Roger

Dr. Joel M. Hoffman wrote:
Beautiful gallery! According to the EXIF data, these are scans. Yes?
Thanks. No, they are all digital, mostly 1D Mark II. There should be no exif
data as the jpegs are stripped to reduce size.

There's lots of EXIF data, with fields such as "Progressive Scans,"
"Device Attributes," etc. I don't know much about the EXIF fields; I
thought those looked like scanner attributes.

BTW, as a reminder:

http://exif.posted-online.com

will display a web page and add EXIF-data boxes for all the images.

-Joel

Interesting. I exified this image:
http://www.clarkvision.com/galleries...8715b-700.html

The info beyond basic image data appears to be entirely due to the embedded
sRGB ICC profile and the jpeg compression. The is no exif data about the
image and its creation. The "Device Attributes," etc. are ICC profile
data.

Roger

ExifTool Version Number : 6.70
File Type : JPEG
MIME Type : image/jpeg
JFIF Version : 1.2
Resolution Unit : None
X Resolution : 100
Y Resolution : 100
Quality : 70%
Profile CMM Type : Lino
Profile Version : 2.1.0
Profile Class : Display Device Profile
Color Space Data : RGB
Profile Connection Space : XYZ
Profile Date Time : 1998:02:09 06:49:00
Profile File Signature : acsp
Primary Platform : Microsoft Corporation
CMM Flags : Not Embedded, Independent
Device Manufacturer : IEC
Device Model : sRGB
Device Attributes : Reflective, Glossy, Positive, Color
Rendering Intent : Media-Relative Colorimetric
Connection Space Illuminant : 0.9642 1 0.82491
Profile Creator : HP
Profile ID : 0
Profile Copyright : Copyright (c) 1998 Hewlett-Packard Company
Profile Description : sRGB IEC61966-2.1
Media White Point : 0.95045 1 1.08905
Media Black Point : 0 0 0
Red Matrix Column : 0.43607 0.22249 0.01392
Green Matrix Column : 0.38515 0.71687 0.09708
Blue Matrix Column : 0.14307 0.06061 0.7141
Device Mfg Desc : IEC http://www.iec.ch
Device Model Desc : IEC 61966-2.1 Default RGB colour space - sRGB
Viewing Cond Desc : Reference Viewing Condition in IEC61966-2.1
Viewing Cond Illuminant : 19.6445 20.3718 16.8089
Viewing Cond Surround : 3.92889 4.07439 3.36179
Viewing Cond Illuminant Type : D50
Luminance : 76.03647 80 87.12462
Measurement Observer : CIE 1931
Measurement Backing : 0 0 0
Measurement Geometry : Unknown (0)
Measurement Flare : 0.999 %
Measurement Illuminant : D65
Technology : Cathode Ray Tube Display
Red Tone Reproduction Curve : (Binary data 2060 bytes, use -b option to extract)
Green Tone Reproduction Curve : (Binary data 2060 bytes, use -b option to extract)
Blue Tone Reproduction Curve : (Binary data 2060 bytes, use -b option to extract)
DCT Encode Version : 100
APP14 Flags 0 : [14], Encoded with Blend=1 downsampling
APP14 Flags 1 : (none)
Color Transform : YCbCr
Image Width : 700
Image Height : 560
Image Size : 700x560

Dr. Joel M. Hoffman wrote:

2b. I know the 30D can follow soaring birds and keep focus. (Take a
look at:


Sorry to follow up on my own post. In response to people who have
asked, I've posted some close-ups on:

http://www.posted-online.com/ArizonaBirds/Page1.html
and
http://www.posted-online.com/ArizonaBirds/Page2.html

and moved the other pages, so the owl- and hawk-series pages are now:

http://www.posted-online.com/ArizonaBirds/Page3.html
and
http://www.posted-online.com/ArizonaBirds/Page4.html

BTW, for a good reason NOT to use JPEG, take a look at the bottom
picture on

http://www.posted-online.com/ArizonaBirds/Page1.html

( http://posted-online.com/ArizonaBirds/pix/14.jpg - 100K ). Notice
the blue hues around the green leaves. There was no blue in the
original picture. Sigh.

Nice shots but I don't know why a jpeg would produce those blues... that
doesn't sound right?

Dr. Joel M. Hoffman wrote:

( http://posted-online.com/ArizonaBirds/pix/14.jpg - 100K ). Notice
the blue hues around the green leaves. There was no blue in the
original picture. Sigh.

I've noticed when slightly over-exposing darks on hard white that there
are similar artificats. Not sure why "blue" comes out.

--
-- r.p.e.35mm user resource: http://www.aliasimages.com/rpe35mmur.htm
-- r.p.d.slr-systems: http://www.aliasimages.com/rpdslrsysur.htm
-- [SI] gallery & rulz: http://www.pbase.com/shootin
-- e-meil: Remove FreeLunch.

On Sat, 07 Apr 2007 18:23:11 GMT, Paul Furman wrote:

( http://posted-online.com/ArizonaBirds/pix/14.jpg - 100K ). Notice
the blue hues around the green leaves. There was no blue in the
original picture. Sigh.

Nice shots but I don't know why a jpeg would produce those blues...
that doesn't sound right?

I don't think it's a jpeg produced artifact. You often get color
fringing when objects have an intensely bright background, such as
the sky, and better lenses produce less of it. The blue in this
shot is probably so easily noticed because it covers a greater area
due to being considerably out of focus. I've noticed CA having
several different colors, sometimes blue, sometimes purple, yellow
or orange. The glossary entry (link below) mentions that CA often
increases when a lens is used at its widest, and that the commonly
noticed "purple fringing" is probably more due to the sensor's
microlenses than a result of the lens's design.


http://www.dpreview.com/learn/?/Glos...rration_01.htm

Ed Ruf (REPLY to E-MAIL IN SIG!) wrote:
On Sat, 07 Apr 2007 18:23:11 GMT, in rec.photo.digital Paul Furman
wrote:

Dr. Joel M. Hoffman wrote:

( http://posted-online.com/ArizonaBirds/pix/14.jpg - 100K ).
Notice
the blue hues around the green leaves. There was no blue in the
original picture. Sigh.

Nice shots but I don't know why a jpeg would produce those blues...
that doesn't sound right?

I've seen something similar , even in raw files from a D70 processed
by RSE. Probably a bit of bloomimg/CA?

I'll conject it's the blue sky, un-overexposed by diminution of
intensity by the palm-frond filter.

Similar effect: Overexposed out of the direct sun, greater color
saturation under the shade of the pier.
http://www.fototime.com/8D5F43553123D59/orig.jpg

--
Frank ess

"Ed Ruf (REPLY to E-MAIL IN SIG!)" wrote in message
...
: On Sat, 07 Apr 2007 18:23:11 GMT, in rec.photo.digital Paul Furman
: wrote:
:
: Dr. Joel M. Hoffman wrote:
:
: ( http://posted-online.com/ArizonaBirds/pix/14.jpg - 100K ). Notice
: the blue hues around the green leaves. There was no blue in the
: original picture. Sigh.
:
: Nice shots but I don't know why a jpeg would produce those blues... that
: doesn't sound right?
:
: I've seen something similar , even in raw files from a D70 processed by
: RSE. Probably a bit of bloomimg/CA?
: --
: Ed Ruf )
: http://edwardgruf.com/Digital_Photog...ral/index.html

I can get that effect with 5D if I use a cheap, long lens wide open and the
foliage is backlit.I always thought it was Chromatic Aberration. Just out of
focus like the rest of the area.

: ( http://posted-online.com/ArizonaBirds/pix/14.jpg - 100K ). Notice
: the blue hues around the green leaves. There was no blue in the
: original picture. Sigh.

I can get that effect with 5D if I use a cheap, long lens wide open and the
foliage is backlit.I always thought it was Chromatic Aberration. Just out of
focus like the rest of the area.

Hmm. It's with the Canon 17-85 IS USM (f/8, 1/640, ISO 500), not a
great lens, but not a cheap one, either.

A long time ago someone posted a digital way of eliminating or
reducing CA, but I've lost the link. My guess is that whatever
digital magic does this won't work with out-of-focus CA, but I'd be
curious to find out. If someone has access to this anti-CA filter,
feel free to play around with the image and post what you learn....

-Joel

----------------------------------------------------------------------------
EXIF data for any image or web page: http://exif.posted-online.com
----------------------------------------------------------------------------

"Dr. Joel M. Hoffman" wrote in message
...
:: ( http://posted-online.com/ArizonaBirds/pix/14.jpg - 100K ). Notice
: : the blue hues around the green leaves. There was no blue in the
: : original picture. Sigh.
:
: I can get that effect with 5D if I use a cheap, long lens wide open and
the
: foliage is backlit.I always thought it was Chromatic Aberration. Just out
of
: focus like the rest of the area.
:
: Hmm. It's with the Canon 17-85 IS USM (f/8, 1/640, ISO 500), not a
: great lens, but not a cheap one, either.
:
: A long time ago someone posted a digital way of eliminating or
: reducing CA, but I've lost the link. My guess is that whatever
: digital magic does this won't work with out-of-focus CA, but I'd be
: curious to find out. If someone has access to this anti-CA filter,
: feel free to play around with the image and post what you learn....
:
: -Joel
:
: ----------------------------------------------------------------------------
: EXIF data for any image or web page: http://exif.posted-online.com
: ----------------------------------------------------------------------------
:
Look for "Flo's tools" This Frenchman has produced a really nice set of very
useful tools which are camera make independent, they just need a PS
compatible program to use as a host.

Dr. Joel M. Hoffman wrote:
You remove the EXIF purposely to reduce the size, or reducing the size
removes the EXIF?

I just went through this dilemma. When I created a web page for my
birds from Arizona, I decided to keep the EXIF data in the
thumbnails. This increased the size of each thumbnaim from about 7K
to about 22K. That's a really big difference, especially for people
using dial-up connections.

Yes, I don't keep it in thumbnails. But for the actual image, say 700
pixels on the long side and probably 50k-100k in size, I leave EXIF and
IPTC data in. I want the location and date and any people identified to
stay with the photos if they're saved and passed around. Of course
that's dependent on the type of photography I do; for many other
subjects it doesn't seem that useful (beyond the date and geographic
location anyway).