Apertures and Vignetting

As you close down your aperture on a "Canon EF 70-200mm f/2.8L IS USM Telephoto Zoom Lens" (this is not the latest version of the lens) the vignetting disappears. 

The following images are a test I did photographing an evenly lit white board from f/2.8 to f/22. (Click on the first image to view larger and scroll through)

 

All images are the copyright of Paul D. Weinrauch and cannot be used without permission. 

                                                                                    ©2013 Paul D. Weinrauch

Custom Camera Profiles and Camera RAW

I started creating my own custom camera profiles using the X-Rite ColorChecker Passport about 2 years ago so that I had more consistent colors between cameras and was using a standard.

Doing this has helped keep my colors in check and have been pleased!

But I starting asking myself, what happens if I move the RAW file(s) to another computer, buy a new computer, or wipe the OS and install a fresh OS. Does the custom profile that I created stay with the file???

Today I ran a quick test. I moved the proprietary RAW format(in my case a CR2) and the sidecar file to another computer. I also converted it to a DNG and moved that file with it.

I then proceeded to open the CR2  (proprietary RAW format) in Photoshop's Camera Raw and it defaulted to the the Adobes profile. UH OH, where was my custom camera profile?

So crossing my fingers, I proceeded to open the DNG in Photoshop's Camera RAW. There it was, the custom camera profile I created was there!

Moral of the story.... Start using DNG and not your cameras proprietary format!

Recent Auto Focus Adjustment

Here is an example of a recent Micro Adjustment I did on a 5d Mark II with a Canon EF 24-70mm f/2.8L I USM lens.

Click on the image to see it larger.

The Auto Focus was off by 10mm (front focusing) and if you are shooting wide open that could be the difference of the bridge of your nose being in focus versus your eyes.

*Update*

I used a Datacolor SpyderLensCal Autofocus Calibration Aid. You can find them at BHPhotoVideo: http://www.bhphotovideo.com/bnh/controller/home?O=&sku=736849&is=REG&Q=&A=details