I'm confused, or just brain dead...

[jl-lb.ms]

OK - see below for info from flickr; i.e. the exif data for a photo I posted. Note "f2.0". How would f2 get in the exif data on a Leica M8???


More detail about Oyster boat AL3203KR


Taken on
March 13, 2010 at 7.13am CST
Posted to Flickr
March 13, 2010 at 8.08AM CST

Edit the photo dates


What is EXIF data?
Almost all new digital cameras save JPEG (jpg) files with EXIF (Exchangeable Image File) data. Camera settings and scene information are recorded by the camera into the image file. Examples of stored information are shutter speed, date and time, focal length, exposure compensation, metering pattern and if a flash was used.
Source: Digicamhelp.
Your privacy
If you like, you can prevent the link to your EXIF data from displaying on the photo page. Set this in your privacy options.

Camera: Leica Camera AG M8 Exposure: 0.001 sec (1/750) Aperture: f/2.0 ISO Speed: 160 Exposure Bias: 0 EV Flash: Auto, Did not fire
File Size: 103 kB File Type: JPEG MIME Type: image/jpeg Image Width: 799 Image Height: 570 Encoding Process: Baseline DCT, Huffman coding Bits Per Sample: 8 Color Components: 3 X-Resolution: 240 dpi Y-Resolution: 240 dpi Orientation: Horizontal (normal) Software: Adobe Photoshop CS4 Windows Date and Time (Modified): 2010:03:10 08:06:33 Exposure Program: Aperture-priority AE Date and Time (Original): 2010:03:13 07:13:37-06:00 Date and Time (Digitized): 2010:03:13 07:13:37 Max Aperture Value: 1.0 Metering Mode: Center-weighted average Light Source: Unknown Color Space: sRGB Focal Plane X-Resolution: 3729 dpi Focal Plane Y-Resolution: 3764 dpi White Balance: Auto Digital Zoom Ratio: 0 Scene Capture Type: Standard Image Unique ID: 000000000000000000000000000010E4 Compression: JPEG (old-style) XMPToolkit: XMP Core 4.1.1-Exiv2 Orientation: Horizontal (normal) Creator Tool: 2.004 Rating: 0 Metadata Date: 2010:03:10 08:06:33-06:00 Format: image/jpeg Color Mode: 3 ICCProfile Name: sRGB IEC61966-2.1 Original Document ID: xmp.did:898D75044F2ADF1191BDB149A2AACC02 History Action: saved History Instance ID: xmp.iid:898D75044F2ADF1191BDB149A2AACC02 History When: 2010:03:10 08:06:33-06:00 History Software Agent: Adobe Photoshop CS4 Windows History Changed: / History Parameters: from image/tiff to image/jpeg Derived From Original Document ID: xmp.did:898D75044F2ADF1191BDB149A2AACC02 Global Angle: 30 Global Altitude: 30 Photoshop Quality: 12 Photoshop Format: Standard Progressive Scans: 3 Scans Viewing Conditions Illuminant Type: D50 Measurement Observer: CIE 1931 Measurement Flare: 0.999% Measurement Illuminant: D65 Flash Return: No return detection Flash Mode: Auto Flash Function: False Flash Red Eye Mode: False

 

[martin s]

The camera makes a semi-educated guess.

martin

 

[jarski]

lens max aperture is recorded to exif, camera pics up this from coding (or in M9, manual configure).

same thing happens e.g with Nikons, with lenses camera cannot contact, but has some programmed setting.

 

[NickTrop]

Verdict? Confused. Brain dead would mean you couldn't post threads.

 

[dfxinc]

are you shooting with a Summicron? Is it telling you the max aperture for the lens.

 

[jarski]

dont have M8 (yet), but remember when using D200 with non-AI manual lens.

there were several ApertureSomething parameters, but since it wasnt able to figure out exact value, effective aperture shown was what I had set from D200 menus as lens max aperture:

AFAperture = 1.0
MaxApertureAtMinFocal = 1.0
MaxApertureAtMaxFocal = 1.0
EffectiveMaxAperture = 2.0
Aperture = 2.0

 

[jl-lb.ms]

This was shot with a Zeiss 35/2 set at 2, with the camera at aperture priority. (So, no lens markings.) Good guess; it got it right. I looked at another shot from the same set, and it correctly labeled it f/4, so not the maximum aperture. Wow.

 

[jarski]

I looked at another shot from the same set, and it correctly labeled it f/4, so not the maximum aperture. Wow.

interesting. I should be able to check this soon too, camera is on the way 😛

 

[swoop]

My M8 has always recorded the aperture as F1on all my lenses.

If you have coded lenses. the M8 will estimate the aperture. Adobe Lightroom makes an estimation as well.

Most of my shots from my M9 are labeled as f2.8 since I use the manual lens selection option.

 

[jaapv]

The blue dot on the camera is a light meter. It reads the ambient light. The camera knows the exposure and deduces the aperture from those data. It is reasonably accurate. The blue dot is used to guesstimate the flash exposure as well to set the preflash as well. It is in EXIF. Some RAW converters - and all exif readers- can record this line.

 

[Phil_F_NM]

Blue dot? I'm curious about this. The little "electric eye" above & to the left of the red dot logo (looking at the camera front) is a sensor for adjusting the info in the VF. It has no bearing on the exposure of the actual image nor the coding of EXIF as far as I can tell. I've had it covered and uncovered for tests to see if it did anything more than adjust the brightness of the light meter info in the VF. It never added any extra data to my EXIF and if it should I need to get mine working. Hmmmm.

 

[ampguy]

probably OK

probably OK

The blue dot is a sensor, but is not used for AE (or manual) metering purposes. It is used for estimating what your ambient light may be, and further, there is a guess f-stop made internally by the camera.

This info. is only used if your lens is coded, with lens detection on, so that with certain known WA lenses, corrections can be made for corners.

Since the deployment of this, it has been found by most to be inaccurate, and can be confirmed by those who've seen over-correction with coding (subscribe to Reid reports, and see for yourself).

Basically, there is no way to estimate, with accuracy, what F stop is used, but measuring ambient light, and assuming 18% grey or so metering used, is a novel technique.

Blue dot? I'm curious about this. The little "electric eye" above & to the left of the red dot logo (looking at the camera front) is a sensor for adjusting the info in the VF. It has no bearing on the exposure of the actual image nor the coding of EXIF as far as I can tell. I've had it covered and uncovered for tests to see if it did anything more than adjust the brightness of the light meter info in the VF. It never added any extra data to my EXIF and if it should I need to get mine working. Hmmmm.

 

[jaapv]

Carsten W. did a statistical analysis of the results and it was not bad as far as accuracy goes. It has indeed nothing to do with the exposure of the camera