Need help regarding photo sharpness.


Pilico

New Member
May 7, 2013
5
0
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24
Singapore
#1
Hi, thank you for coming in.
Please do help me, any guidance will be greatly appreciated.

I read some tutorials and guides teaching how to get sharp pictures but i am still unable achieve it.

Below is one of the photos i took.

The first photo is .jpg from camera, 2nd and 3rd are the blurred ones.
The fourth is converted from raw to jpg after using windows 10 auto enhance but the blur still exist.
On the most left of the 1st and fourth photo, the white color yacht looks weird too.

Equipment used 500D with 28-105 3.5-4.5 II USM
settings =>1/250 sec
f/8
30mm
spot metering mode (i cant remember which part i focused but it should be front of NFT WEST ship.)
iso 100
Aperture priority
Auto white balance

May i know how to improve sharpness on these parts.

$11.jpg
$IMG_1674 (2)1.jpg
$2.jpg
$IMG_1674.jpg
 

JacePhoto

Senior Member
Oct 1, 2007
6,475
9
38
New York City
www.flickr.com
#2
Since no one has helped you, let me try.

There are many reasons for an unsharp photo

1) lens quality (Kit lens vs High end lens)
2) camera quality/ pixel size (ie 12 MP, 24 MP, 36 MP)
3) Diffraction (sometimes the smaller the aperture, it gets you unsharp pictures rather than sharp ones)
4) chromatic aberration

I haven't been following camera models for Canon but I think it may be just a prosumer kind.

Welcome to the club of pixel-peeper. I am one of them and I enjoy my pictures tack sharp too.
 

kandinsky

Moderator
Staff member
Apr 26, 2008
3,013
24
38
#3
Also, to rule out issues with technique like hand shake, try a tripod, with image stabilization turned off, and with a remote shutter or shutter delay. E.g. A simple explanation is that you could have focused on the half-press, then moved slightly before/white you hit the shutter.
 

Feb 7, 2010
120
0
16
Singapore
#4
Another possibility: DSLR has a mirror to reflect light to an AF module. It needs to be calibrated WRT the lens. The problem may lay with the sensor positioning wrt the AF module and it might be the lens. Some camera bodies have micro adjustments by lens ID that users may set to achieve accurate focus.

In contrast, mirrorless eliminates that AF module and place the sensors on the image sensor itself. This practically eliminate the need for users to calibrate the lens.

Other possibilities that came to mind that could cause problem is mirror slap and shutter induced shake. Many work around are mirror lock up, electronic front curtain shutter, etc.

Hope this help


Sent from my iPad using Tapatalk
 

one eye jack

Senior Member
Jun 11, 2011
791
8
18
#5
Since no one has helped you, let me try.

There are many reasons for an unsharp photo

1) lens quality (Kit lens vs High end lens)
2) camera quality/ pixel size (ie 12 MP, 24 MP, 36 MP)
3) Diffraction (sometimes the smaller the aperture, it gets you unsharp pictures rather than sharp ones)
4) chromatic aberration

I haven't been following camera models for Canon but I think it may be just a prosumer kind.

Welcome to the club of pixel-peeper. I am one of them and I enjoy my pictures tack sharp too.
Your answers hit the most bull's eye...:thumbsup:

1) lens quality (Kit lens vs High end lens)

EF28-105 F3.5-4.5 usm II - Some say it sucks on APSC sensors while others say it's good from F7.1 but better from F8 - F11. Does a PRO lens like L series really do better? Also do remember this is EF lens for full frame film cameras.;) Edit: Some say kit lens perform better than this old lens.

2) camera quality/ pixel size (ie 12 MP, 24 MP, 36 MP)

Sensor size do have a co-relationship to sharpness/resolution but don't really determine final output of image.Nikon's pro cameras of old is only 12Mp compared to canon 500D's 15Mp.So what gives?

3) Diffraction (sometimes the smaller the aperture, it gets you unsharp pictures rather than sharp ones)---see 1.


4) chromatic aberration ---See 2nd. photo at 100X. Colour fringes at the edges of the ladder mast. Now look at the photo in Ken Rockwell's review of 28 -105 usm II. Shot on Canon 5D MK3 full frame.This advance camera has built-in lens correction for CA ( chromatic aberation)plus other goodies. Notice the photo is post card size rather than big enlargement ,it's razor sharp to the eye. What's the secret apart from lens correction?

Edit: Note that you can correct for CA (chromatic aberation) in photoshop and may be in Lightroom (newer version) I think.

Here's the secrets...

1. Camera settings - set noise reduction to off.It affects jpeg image quality.RAW is left untouched.

2. Use lowest ISO. Know what is the "native ISO" of the camera's sensor.This is the ISO that gives
the best resolution. Truth is there is only ONE ISO - native iso.:bigeyes: It's also the real analog output (voltage signal) of the sensor vs amplified ISO rating eg. If native is 100 then 200,400,800,1600 are pushed or amplified signal. As common knowledge the more signal is amplified ( bigger amplitude) the more electrical noise it generates. Hence to turn off all noise reduction settings. Read the native ISO links below, it's an eye opener! Rather than pushing digitally ISO ,pulling ISO eg. 125,250, etc. has benefits -- better dynamic range in terms of exposure. Note some sensors native is at ISO 200 but can set to 100 which is digital pulling ( reduced amplification of actual analog signal).

3.Image sharpness, the science of optics or lens engineering. It's relative meaning the
term known as accuity. It can be defined as how a lens resolve fine details (hardware/lens quality) or how humans see how sharp an image is. This is primarily about image contrast vis-a-vie sensor resolution. See Cambridgeincolour article below.

So in essence if the lens cannot resolve fine details it can be enhanced by image processing -boost/increase image contrast.You only sharpen image LAST after all other adjustments are done like white balance,colour,etc.Note if you got the exposure spot on/correct this contrast adjustment will not be necessory.Sharpen adjustment actually
increase contrast of light and dark areas especially along lines or edges to simulate optical/lens accuity or sharpness.

4. Understand how camera meter works and how to compensate the exposure.Read Ansel Adam's Zone system of exposure, the famous zone 5 relative to the other zones.Know and recognise what these zones are in a scene you compose. Edit: Strange that TS use spot metering when the overall scene's brightness/contrast does not require it when matrix mode or whatever canon calls it is sufficient.

5. Shoot in RAW or RAW + Jpeg. Gives you a better chance of retrieving fine details/dynamic range when post processing.

6. Use a better image processing software other than the one included in the camera's CD like Lightroom or photoshop. If after all this you cannot take sharp photos please kick yourself..just joking.:bsmilie:


http://kenrockwell.com/canon/lenses/28-105mm.htm

http://www.cambridgeincolour.com/tutorials/sharpness.htm

http://www.imatest.com/docs/sharpness/

http://improvephotography.com/686/tips-sharper-photography-sharpness/

Native iso:

http://www.bobatkins.com/photography/digital/canon_digital_rebel_T1i_review_3.html

http://shootintheshot.joshsilfen.com/2010/05/13/canon-hd-dslr-native-iso/
 

Last edited:

Kermitfm

New Member
Mar 10, 2007
301
2
0
#6
Some of my thoughts based on your sample photo.

The shutter speed and aperture setting for the focal length used are good enough to eliminate camera shake. I think your main problem is the lens.

If you do research on the 28-105, it is not especially a good lens for pixel peeping. In fact, most non-professional lens are not good for pixel peeping. If you want tack sharp photos at 1:1 viewing, you need good lens (and of course, the good techniques suggested by the posts above).

Using a lens comparision tool, here are the 1:1 test image taken with the 28-105 at f/8 and 35mm. The camera boy is Canon EOS Ds MkIII. The area taken is the corner where lens performance is the most lacking.

$28_105.jpg

Here is the same settings and camera but with the 24-105 L lens.

$24_105L.jpg

You can see the difference. For your information, there is minimal difference in the quality/sharpness of the image in the middle of the frame.

Should you upgrade? It will depend on your need. If you are just capturing images for the web and/or printing to 4R size, I don't think the quality difference matters that much. If you are picky and have spare cash, then ... your decision.

Note: I am not sure if the link works, but if you want to play around with the comparision tool, go to: digital picture

Hope this has been helpful.
 

SkyStrike

Moderator
Staff member
Nov 29, 2010
3,444
11
38
Somewhere
#7
From what I see from the original photo, (as others pointed out) it don't seem like camera shake, and it doesn't seems like mis-focused either. So I can only suspect that it's the lens image quality rather than the mechanics of the lens.

Since I do not own this lens, I can't really be sure if this is how the lens should perform even when it's tuned to it's best... But, if you suspect that your lens was never this soft in the past, you might want to bring it down to the service center and let the technicians take a look to see if any of the lens elements have shifted.