Image seems soft

I'm new to digital, so please bare with me. I have a 20D. When I shoot with my Tamron 70-300 (f4/f5.6), and I zoom long to 300 mm or near 300 mm, with autofocus on, the images that I download and view in Photoshop Elements seem a little on the soft side when viewed at 100%, even where my focus point was when I took the shot. At 70 mm or 135 mm (+/-), things look a little crisper. The same is true with my Sigma 170-500 (f5/f5.6). The Sigma images that I'm thinking of were taken at 1/1600 on a sunny day, without a tripod, but supported by a fence. The Tamron images were taken from a tripod and a remote switch. I took the shots in large JPG format on the 20D. I don't know much about Photoshop, but the instructor in a class I'm taking told us that with a large format JPG on a 20D (or other cameral with 8+ megapixels), we can print images up to 16" X 20". If I were to print the images that I referred to at that size, would I see some of the softness that I mentioned? Is the depth of field just so small at those focal lengths that I'm missing it? Or is it a limitation of the lens? Is it both? Am I expecting too much from the lenses to be able to print something that large at that focal length? Don't get me wrong, the softness at 100% at those focal lengths doesn't seem to be unacceptable, it's just that I know things can look sharper because I've seen images shot under the same lighting conditions, but at a smaller focal length. Would I even notice the slight softness that I do at 100% on the long focal length shots when I print at a more reasonable size, say 8X10 or 5X7? I'd experiment, but I don't have a photo printer yet.

Sorry to be so much trouble.

Thanks for the help.

Can you post some images to show us what you are considering soft? I don't know much about the Sigma 70-300mm, but I do have the 170-500mm APO lens. To be honest with you, it's not the sharpest lens in my bag, nor the softest, but it does pretty good, even at 500mm, as long as you can keep it steady. Have you tried adding some unsharpen mask in photoshop? It does wonders for digital, but be carefull not to get too crazy with it. Too much will add a halo around your images. I don't think I have printed anything taken digitally with my 170-500mm yet so I can't tell you what the images look like enlarged and printed. Sorry I can't be of more help to you.

I can't post them now, because there on my PC at home. But I will post them when I get home. Dumb question- how do you post a photo in these forums?

Quote:

---

Originally Posted by siberia1997

I'm new to digital, so please bare with me. I have a 20D. When I shoot with my Tamron 70-300 (f4/f5.6), and I zoom long to 300 mm or near 300 mm, with autofocus on, the images that I download and view in Photoshop Elements seem a little on the soft side when viewed at 100%, even where my focus point was when I took the shot. At 70 mm or 135 mm (+/-), things look a little crisper. The same is true with my Sigma 170-500 (f5/f5.6). The Sigma images that I'm thinking of were taken at 1/1600 on a sunny day, without a tripod, but supported by a fence. The Tamron images were taken from a tripod and a remote switch. I took the shots in large JPG format on the 20D. I don't know much about Photoshop, but the instructor in a class I'm taking told us that with a large format JPG on a 20D (or other cameral with 8+ megapixels), we can print images up to 16" X 20". If I were to print the images that I referred to at that size, would I see some of the softness that I mentioned? Is the depth of field just so small at those focal lengths that I'm missing it? Or is it a limitation of the lens? Is it both? Am I expecting too much from the lenses to be able to print something that large at that focal length? Don't get me wrong, the softness at 100% at those focal lengths doesn't seem to be unacceptable, it's just that I know things can look sharper because I've seen images shot under the same lighting conditions, but at a smaller focal length. Would I even notice the slight softness that I do at 100% on the long focal length shots when I print at a more reasonable size, say 8X10 or 5X7? I'd experiment, but I don't have a photo printer yet.

Sorry to be so much trouble.

Thanks for the help.

---

Most beginners do not realize that digital images, from cameras or scanners, need to be sharpened. This is particularly true with Canon cameras. Canon tends to reduce the in-camera sharpening to a minimum to let you add what you want. Sharpening can always be added, you can't "undo" it once its there. A DSLR image needs post-processing to get the best results.

Now that you mention it, why is that digital images need sharpening?

Quote:

---

Originally Posted by siberia1997

I can't post them now, because there on my PC at home. But I will post them when I get home. Dumb question- how do you post a photo in these forums?

---

Click on Reply to this post, and scroll down past the Submit Reply button, and click on the upload photos button. You will be able to search for you photos. You may have to resize them to fit. Max size is 640X640 pixels I believe.

You can also do this by clicking on the Quick Reply button, and the clicking the Go Advanced button.

I have the Tamron 75-300 f/4-5.6, and it does tend to get soft at 300mm. Of course, the DOF will be really shallow, and sometimes AF doesn't get the exact spot you'd hoped...But I've noticed that images at 300mm are softest when the subject is pretty reflective, because light tends to halo around it. Here's a couple of 100% crops to show you what I mean. The deer is actually pretty sharp despite being shot at 300mm handheld, but the bird shot shows how the chromatic aberrations can affect sharpness...So basically, you just have to be really careful about the light you shoot in, and try to avoid going out much longer than about 250mm.

Quote:

---

Originally Posted by Norfindel

Now that you mention it, why is that digital images need sharpening?

---

I'm not an expert but I know it has to do with the loss of " acutance" during the digital process. Acutance is a complex topic that boils down to sharpness. Digital loses actuance because of information that is getting lost. From Luminous Landscape: "...we resort to the old law that two wrongs make a right. We throw away even more information in the hopes that what is left gives the illusion of the original acutance."

Adding back sharpness takes experience. I know I grossly oversharpened when I first started out. Some consumer P&S cameras do this in-camera. People love them at first but, after a while, start to see problems. It takes a careful balance! This is why I make very sure to keep the original images in a safe place. When I learn more, I can go back to these originals and try again!

I was just reading a book today about post processing digital images. They talked about waiting till the final step to sharpen the image. The reason behind this is that the more you work with an image, the softer it becomes. Is this accurate? I have heard people say on these boards that they sharpen in small amounts throught the entire post processing process. Is there a right or wrong time to add sharpening to the process of creating you image?

I posted an image shot at 500 mm, f/5.6 at 1/1000 sec. The image, in Large JPG format on my 20D, was quite large in Photoshop. It may not be possible to see the softness that I see when I view at 100% in Photoshop, but maybe you can.

From what I'm reading on this forum, and others, it seems to be a trait of consumer lenses.

Quote:

---

Originally Posted by siberia1997

I posted an image shot at 500 mm, f/5.6 at 1/1000 sec. The image, in Large JPG format on my 20D, was quite large in Photoshop. It may not be possible to see the softness that I see when I view at 100% in Photoshop, but maybe you can.

From what I'm reading on this forum, and others, it seems to be a trait of consumer lenses.

---

Have you applied any USM to this image? I tried it, and it made a huge difference. Also, increasing contrast will do a lot to increase apparent sharpness. I did both to your pic and it worked pretty well. I'd say what you are seeing is not OOF softness, but simply a lack of strong in-camera sharpening. I prefer that the camera do as little sharpening as possible, so I can do it myself...You could probably bump up the in-camera sharpening if you don't want to do it in PP though....

Quote:

---

Originally Posted by siberia1997

From what I'm reading on this forum, and others, it seems to be a trait of consumer lenses.

---

Yes and no. Consumer lenses are generally a lot softer than top of the line L series lenses and will require more post processing sharpening than say an L series lens. Even the top of the line lens, is going to need some sharpening when shooting digital. It might not need near as much post processing work, but it will need some.

I'm no professional, but I sharpen last. And I sharpen it depending on what the purpose is.

If the image is full resolution and I'm planning on printing it, I may sharpen some with the radius less than one pixel -- if needed... I do not like the paper doll "cut-out" look of over-USMed images. Note also, that an image sharpened for printing may look over sharpened on your monitor.

If you down-size an image for posting on the web (like here at PR.com), then sharpening is definitely required to bring back the crispness of the original.

BR,
Tim

Siberia1997- You said in your first sentence that you are new to digital. You obviously have photography experience in film, judging by the way you phrase your questions.

There are a couple things that you should be aware of as generalizations for digital shooting.

I own and shoot Canons (300D and 20D) so my comments are related to these devices primarily.

Canon designs and builds their DSLR models to give the shooter, a bunch of options that P&S generally lack. They also set defaults to the least amount of "in-camera" processing, letting the owner set parameters to their own preferences.
A common complaint from new DSLR shooters is the fact that their shots look soft, out of focus, flat, etc. Much of this is due to my statement above. Many people are used to the oversaturated/crisp prints from labs and sub-conciously expect their own shots to look the same.
If you cruise the different forums, you will notice how many topics deal with post-production of the images and the various software packages used by digital folks.
The simple fact is that now YOU are the lab/darkroom. Along with the digital technology of cameras, you (like it or not), are it. Some love it (me) some hate it, but we all have to do it.

My second comment is the lens issues you bring up. Again the focusing points you chose have an effect - your focusing parameters (AI,AI servo, etc) have an effect - your sensor size is smaller, as the focal length increases your DOF decreases - on-and-on.

There is a definate so called learning curve and it sounds like you are getting into it full bore.

Hang in there - all will be revealed !