how sharp is sharp enough?

Folks,

Need a bit of advice here…I’m trying to get into grips with my new 20D, my first DSLR. One persistent comment I'm getting from my brother, a die hard 35mm, is that my photos are not sharp enough.

Here is an example:

http://home.btconnect.​com/mossbox/AES/test/I​MG_1015.JPG

Lens is EF 50mm 1.4 USM. Auto focus point is on the mouth and here is a relevant crop http://home.btconnect.​com/mossbox/AES/test/u​ntitled.JPG


Do you think there is something wrong with my camera (I am aware of the 45 deg sharpness test and will get around to do it next week), the lens or my brother?

ta

ds

Post the Exif data for your shot. Could be a simply issue of shutter speed.

Here it is:

Camera Model
Canon EOS 20D
Shooting Date/Time
19/02/2006 13:09:43
Shooting Mode
Aperture-Priority AE
Tv( Shutter Speed )
1/80
Av( Aperture Value )
3.2
Metering Mode
Evaluative Metering
Exposure Compensation
0
ISO Speed
100
Lens
50.0 mm
Focal Length
50.0 mm
Image Size
3504x2336
Image Quality
Fine
Flash
Off
White Balance Mode
Auto
AF Mode
One-Shot AF
Parameters Settings
Contrast Standard
Sharpness Standard
Color saturation Standard
Color tone 0
Color Space
sRGB
Noise Reduction
Off
File Size
3481 KB
Custom Function
C.Fn:01-2
C.Fn:02-0
C.Fn:03-0
C.Fn:04-0
C.Fn:05-0
C.Fn:06-0
C.Fn:07-0
C.Fn:08-1
C.Fn:09-0
C.Fn:10-0
C.Fn:11-0
C.Fn:12-0
C.Fn:13-0
C.Fn:14-0
C.Fn:15-0
C.Fn:16-1
C.Fn:17-0
C.Fn:18-0
Drive Mode
Single-frame shooting

Looks like some front-focusing or misfocus. Look at the tree right next to her head (slightly in front of her). It's relatively sharp. Are you sure you focused on her mouth?

Your shutter appears fast enough to rule out camera blur. Did you do any post-processing on this image at all, or is it straight from the camera? I see what you mean about the crop not being very sharp. Hopefully, someone with this lens will be able to comment.

PS: You may want to actually get off your duff and do some formal lens tests. I'm not an advocate of constant pixel-peeping but you should make sure your lens is up to spec and can focus properly.

Did you have only the center AF on? To my eye, it looks like the camera was focusing on her hair rather than her mouth.

ok I had a look and I notice you used the right focusing point, I dont know if that has anything to do with it but the center point is the best to use.

Also I found with this lens the shutter speed has to be higher than 100 to get sharp images but then I have shaky hands, it also looks like your lens is front focusing but please try the focusing test first.

I have done a 100% crop of your image and sharpened it and it dont look too bad.

Bruce

IMAGES REMOVED. IMAGE OWNER HAS NOT GIVEN PERMISSION TO EDIT/REPOST PHOTOS!
See https://photography-on-the.net/forum/showthre​ad.php?t=115805 for more info

Ditto... you have an extremely sharp tree to the left of your subject.

Could be a bit of subject movement also. 1/80s is typically good enough to prevent blur from camera shake, but it's pretty slow for a candid of a person. For a shot like this I prefer to use something like 1/200s.

Considering that the red channel is clipped on the subject's face, I agree with Bob. It wouldn't have hurt to go with a faster shutter. This would also mitigate the CA issues on the branches on the left. I don't really have an issue with histograms that clips in the highlights, but clipping in the subject area is inexcusable - and not really salvagable, making sharpness a moot point. This is a perfect situation for a flash, BTW. Depending on how much flash you use, you could bring the sky in the background down at least a stop.

follow up on: how sharp is sharp enough?

Many thanks – loads of useful stuff. Some answers to points raised plus some follow up q:

• Flash – distance was too far for the build in flash and I didn’t have with me an external unit. jfrancho – could you please expand on CA point (is this to do with the fairly bland colours?)

• Shutter speed – could have done with faster. Maybe by increasing sensitivity to ISO to 200?

• Post processing – I am well impressed with the effect of what sony23 did. What exactly do you mean when you say you did 100% crop of the image and sharpened. Am I right to assume that you blew it up to allow 1 pixel of the photo equals 1 pixel on the screen and then used PS sharpening?

• Focusing on right a/p point – I’m still experimenting with this but I am aware EOS owners are strongly encouraged (by Canon) to abandon ‘point-recompose-shot’ and instead use the a/p point that will actually be used in the final composition. How to get over old habits is a subject for another thread i guess (currently i am trying fn4=3).

CA = Chromatic Aberration. Look at the tree branches on the left ay 100% or better and you'll see the red and green ghosting, smearing. Overexposure seems to exagerrate that. Given that you used a 50mm focal length, I'd say you were cose enough for the built in flash - my DRebel works fine at this distance. As far as upping ISO, I couldn't say for sure, but since the exposure blown to begin with, you would either increase shutter, and or aperture before raising ISO. To get a 100% crop, open the image in a an editor, zoom to 100%, use a selection tool to make a crop that will fit on the screen, save without resizing, now you have a 100% crop. It's a portion of the image displayed at 1:1, or 100% without having to upload/download the whole image. It is for convenience.

OK, got around to do a formal focus test. Snap taken from a distance of around 40cm. Seems to me that auto focus certainly gets it right in terms of focusing to the correct distance. What i am still unconvienced about is the softness of the focus. What do you think?

Here is the file: http://home.btconnect.​com/mossbox/AES/test/I​MG_1028.jpg

Here is the exif:

File Name
IMG_1028.JPG
Camera Model
Canon EOS 20D
Shooting Date/Time
22/02/2006 21:25:45
Shooting Mode
Manual Exposure
Tv( Shutter Speed )
1/200
Av( Aperture Value )
1.4
Metering Mode
Evaluative Metering
ISO Speed
100
Lens
50.0 mm
Focal Length
50.0 mm
Image Size
3504x2336
Image Quality
Fine
Flash
Off
White Balance Mode
Tungsten
AF Mode
One-Shot AF
Parameters Settings
Contrast Standard
Sharpness Standard
Color saturation Standard
Color tone 0
Color Space
sRGB
Noise Reduction
Off
File Size
1970 KB
Custom Function
C.Fn:01-2
C.Fn:02-0
C.Fn:03-0
C.Fn:04-0
C.Fn:05-0
C.Fn:06-0
C.Fn:07-0
C.Fn:08-1
C.Fn:09-0
C.Fn:10-0
C.Fn:11-0
C.Fn:12-0
C.Fn:13-0
C.Fn:14-0
C.Fn:15-0
C.Fn:16-1
C.Fn:17-0
C.Fn:18-0
Drive Mode
Self-Timer Operation

Image quality - Fine, and not Raw. JPEG algorithms blur or smudge the pixels. Doing a focus check on this is not that useful. Use RAW quality, and apply no sharpening to see what you are getting.

Note that due to the Beyer pattern interpolation of the sensor data, you cannot get a 1-pixel edge.