DOF Notes:1 - Head shots using a 50mm lens.

[jaspreetsinghrawel]

Hi Richard,

I have just started photography as a hobby.

I clicked the attached photograph using the below settings using a Canon 550D with Canon EF 50mm 1:1.8 II lens in the evening when the there was no sunlight and it was about to get dark but day light was there.

AV Mode, 1/60, f/1.8, ISO 200, RAW format

Image size - 21.5 MB

I used ZOOM browser to save the image as in JPEG format - the size got reduced to around 930 KB.

The image as seen in the attachment is not very sharp. Can you please suggest the corrections?

Thank you,

Regards,
Jaspreet Singh

[RichardTaylor]

That lens is not real sharp at F1.8/F2.

Try shooting it at F2.8 (or F4 )at the very minimum.

Keep in mind you almost always need to sharpen the image when shooting in RAW (It's the last thing I do)

[Doug Sundseth]

Minor comment on something you said earlier in this thread:

While it's true that sensor size has no direct effect on DoF, if you have two sensors with the same number of photo sites and different sizes, you'll get greater DoF with the larger sensor for a given focal length and aperture. This is true because the the minimum resolvable detail size can be no smaller than the size of a photo site, so any blur less than that size will not be seen.

That is, the circle of confusion for a larger photo site is larger than it is for a smaller photo site, so the Depth of Field at critical sharpness will be greater for the larger photo site. (Try it at DoFMaster.)