PDA

View Full Version : Anyone use a 5D w/a Tamron 17-50 2.8 ?


jgoetz4
Sep-26-2008, 05:54 AM
Morning Folks,
Has anyone used a 5D with a Tamron 17-50 2.8 lens ? I know it will vignette to a certain extent, but I was curious as to what the image looks like around 20-24mm @ 5.6 or so. Sample pics would be appreciated if anyone has them.
Thank you very much and have a good day :D
Jim...

tjstrider
Sep-26-2008, 07:21 AM
It is my understanding that the Tamron 17-50 is the equivilant to a Canon Ef-S lens therefore not compatible.

duronboy
Sep-26-2008, 07:38 AM
It does fit, technically, but the vignetting is more severe than the average EFS lens on a full frame, at any aperature. If you do try it, be sure to use partial metering.

ziggy53
Sep-26-2008, 07:46 AM
It does fit, technically, but the vignetting is more severe than the average EFS lens on a full frame, at any aperature. If you do try it, be sure to use partial metering.

Duronboy, welcome to the Digital Grin. :clap

Thanks for the informative comments.

jgoetz4
Sep-26-2008, 07:50 AM
Morning Folks and thanks for getting back to me :thumb
I was curious about the size of the image circle, compared to the image circle of my Tamron 24-135mm, which is a ff lens. The 17-50's image circle is larger then the 24-135's image circle, that why I wanted to see some pics :wink Thanks again.
Have a good day :D
Jim...

jgoetz4
Sep-27-2008, 03:24 PM
Good Evening Folks,
I have attached a picture of the Tamron 17-50 2.8 and the Tamron 24-135mm, which is a ff lens. The 17-50 clearly has a bigger image circle, but apparently vignettes on a ff camera, whether digital or film. Just curious as to why this would happen to the 17-50, and not the 24-135.
Thanks ahead of time :thumb
Have a good evening :D
Jim...

ziggy53
Sep-27-2008, 03:56 PM
Jim,

The "Image Circle" of a lens is the projected image from the lens onto the film plane (or image plane in the case of digital).

Take those two lenses and a sheet of white paper. Go outdoors on a bright sunny day. Find some shade, the inside of a car or van will do, and use the lenses to project an image of the bright scene onto the white paper. Use the FF lens first and mark roughly the approximate image size on the paper when the image is in focus.

Now repeat the process with the "crop" lens. See how much smaller the projected "image circle" is on the crop lens?

jgoetz4
Sep-27-2008, 04:07 PM
Jim,

The "Image Circle" of a lens is the projected image from the lens onto the film plane (or image plane in the case of digital).

Take those two lenses and a sheet of white paper. Go outdoors on a bright sunny day. Find some shade, the inside of a car or van will do, and use the lenses to project an image of the bright scene onto the white paper. Use the FF lens first and mark roughly the approximate image size on the paper when the image is in focus.

Now repeat the process with the "crop" lens. See how much smaller the projected "image circle" is on the crop lens?
Good Evening Ziggy and thanks for the response :thumb
My bad, since I thought the image circle was the actual "back" of the lens opening. That's how it was explained on another forum some time ago.
Thank you for the clarification. I will compare the two lenses on the next sunny day.
Have a good evening :D
Jim...