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Novaheart
19th of July 2006 (Wed), 11:11
Does anybody know how to find the ISO information after an image has been downloaded to a computer? When I right click on an image and check out the properties/summary/advanced I see lots of info but no ISO setting (this is an image I changed the ISO manually BTW). You can see ISO on the camera when you press the display button while in playback mode so it should be downloaded to the computer. I've also tried finding it in Photoshop and it does have a place for ISO but it's an empty box with a blinking cursor, although it doesn't let you enter anything in there. It's not that important to me but I was just curious :)
Also, I was wondering if it's a common feature for a camera to have the histogram displayed onscreen while you're taking a picture? I think my A620 can only display the histogram in playback mode. I once tried somebody's Casio camera and thought it could show the histogram over the live image.

Rob

spur
19th of July 2006 (Wed), 11:22
The way I understand it is Canon puts the ISO info in a nonstandart place for whatever reason. That makes it hard for most standard EXIF readers to find it. Your Zoom Browser is the only sure way to find it that I know of.

The live histogram is a new feature in the S3 so I don't think it is standard yet but may start showing up a lot more.

PhotoJourno
19th of July 2006 (Wed), 11:30
Hi there. Try http://www.softpedia.com/progDownload/Exif-Reader-Download-11954.html , this is what I use when I am not using Canon Software, or Adobe Bridge (From CS2 Suite).
Cheers,

nwyman
19th of July 2006 (Wed), 11:31
well, I'm not sure how helpful this will be. I just tried checking this out with the Zoombrowser software that came with my camera - you have to use the original shot, for some reason lots, if not all, of the EXIF data disappears once you've edited it.
Anyway - I found an old shot, taken with my S2 and was able to find that it was taken with AUTO ISO setting by clicking at a box on the upper right hand of the screen that looked like a rectangle with some paper in it. (not very technologically advanced here!).

As for the live histogram, I don't think any of the non-pro level Canons have that - I know my XT doesn't - not sure about the 30D. Would be nice, wouldn't it? Guess we're lucky to have what we do.

PhotoJourno
19th of July 2006 (Wed), 11:56
I know 10Ds do not have live Histogram. It would be a nice feature for the wishlist, so long as it would not delay any other process. I recently purchased a Sony Powershot for my grandfather, with all the fancy features, however from the time you pressed the shutter, to the red beam AI focus, IS, Live Histogram, and subsequent shot with flash, it was almost 2 seconds. I like that my Canon takes the photo as soon as I push the shutter.

As for the EXIF data, you definitely want to use programs that will not erase that info. For example, my Canon software and Photoshop allow me to keep the Exif Data, but if I open an original image with Microsoft's Photodraw, as soon as I edit something and save, the Exif is gone bye-bye.

Hope this helps.

ssd
19th of July 2006 (Wed), 12:09
So far as your ISO problem is concerned I suggest to use a good EXIF reader software.
You may try the link below. I am using it in conbination with S2. You will get the ISO value there.

http://www.takenet.or.jp/~ryuuji/minisoft/exifread/english/

ssd
19th of July 2006 (Wed), 12:29
This thread has been duplicated somehow. Find more discussions in the twin.

Moppie
19th of July 2006 (Wed), 16:23
A live histogram requires exposing the sensor to the image, which is a little hard to do with an SLR, the mirror tends to get in the way ;)

Iv used a Sony with a live histogram, IMO it was just a pain in the ass, it responded to slowly, and often didn't reflect what the actualy photos histogram would be.
It also got in the way when trying to compose with the LCD (the view finder was so small it was a waste of time).

If the technology behind them has advanced somewhat, then I can see them being useful, however I can look at a scene now and have a pretty good idea of what the histogram will look like just from experiance.

Novaheart
21st of July 2006 (Fri), 10:50
Thanks to everyone who responded, I always learn a few things from you guys. I guess my biggest problem is that I haven't installed the Canon software that came with the camera, at the advice of my brother. :lol: That's the reason I didn't know I could remotely control the camera using a computer in my "bracketing" post. Maybe I should check out the software manual ;)

Oh, and sorry about the double post. Is there a way to delete your own posts?
Rob

waussie
21st of July 2006 (Fri), 11:22
Irfanview (freeware) gives details:
File: - C:\My Documents\z20060518_arvo_194.jpg

Make - Canon
Model - Canon PowerShot S2 IS
Orientation - Top left
XResolution - 180
YResolution - 180
ResolutionUnit - Inch
DateTime - 2006:05:18 15:47:24
YCbCrPositioning - Centered
ExifOffset - 196
ExposureTime - 1/250 seconds
FNumber - 3.50
ExifVersion - 0220
DateTimeOriginal - 2006:05:18 15:47:24
DateTimeDigitized - 2006:05:18 15:47:24
ComponentsConfiguration - YCbCr
CompressedBitsPerPixel - 5 (bits/pixel)
ShutterSpeedValue - 1/251 seconds
ApertureValue - F 3.51
ExposureBiasValue - -0.67
MaxApertureValue - F 2.71
MeteringMode - Multi-segment
Flash - Not fired, compulsory flash mode
FocalLength - 6.00 mm
UserComment -
FlashPixVersion - 0100
ColorSpace - sRGB
ExifImageWidth - 800
ExifImageHeight - 583
InteroperabilityOffset - 2174
FocalPlaneXResolution - 11520.00
FocalPlaneYResolution - 11571.43
FocalPlaneResolutionUnit - Inch
SensingMethod - One-chip color area sensor
FileSource - DSC - Digital still camera
CustomRendered - Normal process
ExposureMode - Auto bracket
WhiteBalance - Manual
DigitalZoomRatio - 1.00 x
SceneCaptureType - Standard

Maker Note (Vendor): -
Macro mode - Normal
Self timer - Off
Quality - Superfine
Flash mode - Not fired
Sequence mode - Single or Timer
Focus mode - Single
Image size - Large
Easy shooting mode - Manual
Digital zoom - None
Contrast - Normal
Saturation - Normal
Sharpness - Normal
ISO Value - 50
Metering mode - Evaluative
Focus type - Auto
AF point selected -
Exposure mode - Tv-priority
Focal length - 600 - 7200 mm (100 mm)
Flash activity -
Flash details -
Focus mode 2 - Continuous
White Balance - Sunny
Sequence number - 0
Flash bias - 0.00 EV
Subject Distance - 59
Image Type - IMG:PowerShot S2 IS JPEG
Firmware Version - Firmware Version 1.00
Image Number - 1000080
Owner Name - Teaman
But image number is incorrect:)
Faststone (freeware) gives a lot less.

PhotoJourno
21st of July 2006 (Fri), 11:43
What was that!!! It felt like a Broadband Enema... Lots of information there. ;)

Histograms are essential to digital photography. One can always edit images based on good eye and common sense, but when you are editing for printing (say an album for your first wedding), just because it looks good on your screen does not mean it will print exactly the same.

Luminesence Histograms are my favorite feature of Digital Cameras. Specially when I put them in Photoshop (CS2 is mine), and I get the Histogram per color, it really allows you to see "Into the Matrix" of the photo, and give you info on what colors and shades are predominant, shiny and dark spots, and other distribution. It has the potential to help you turn a decent photograph into a greatly balanced and eye pleasing image.

I am very glad you are finding your way, and strongly encourage you to learn as much as you can about histograms. Just google it, and I am sure there will be enough material to at least get started. The time I used to spend in the darkroom, I usually spend editing and studying the Histogram. For some, it is a guideline, for those who have a technical mind and are used to charts and graphics, it holds a wealth of information.

Cheers,

Gerry@Rick
30th of July 2006 (Sun), 11:04
A live histogram requires exposing the sensor to the image, which is a little hard to do with an SLR, the mirror tends to get in the way ;)



I think that you may have answered my question. With the 350 I get the histogram when I've taken a shot but hadn't been able to work out if it is possible before I press the button. It would be useful to have it before I shoot but I suppose I can always scrub the shot if it is duff. It's that mirror getting in the way that's the problem. :lol: