Is this acceptable image quality?

01/21/2009 01:44:43 AM · #4

What %crop/zoom are we looking at here?

chromeydome

Nikon D7000

01/21/2009 01:52:20 AM · #5

Are you doing any post processing of the raw image file before exporting to a jpg? A raw file is not suitable for direct use without pp.

Go into aperture and try a bit Definition slider, some Vibrancy slider and just a bit of Sharpening, then export another: you should see a big difference

Bear_Music posted a really good explanation about this in a thread just yesterday--hunt it down (I would do that for you but
I am typing this on my iPhone & my patience is insufficient :)

Covert_Oddity

Nikon D700

01/21/2009 02:12:29 AM · #6

Pretty much every shot I bring into Aperture using RAW I push the "definition" slider up around half way, otherwise the images look soft, even using prime lenses. I do think your shot looks a little too soft, read some reviews on the lens and see if that's normal at the far end of the zoom.

roba

Canon EF 70-200mm f/2.8L IS USM

01/21/2009 02:38:40 AM · #7

That definitely does not look right. That thing should be razor sharp.
Might want to try out a focus test, like the ones here or here.

dwterry

Canon EOS-1D Mark III

01/21/2009 08:42:38 AM · #8

There was a similar thread posted here. But there is a HUGE DIFFERENCE between your thread and the other one. The other one was using f/8 and yours is using f/2.8.

One common problem between both of your threads is that your pictures lack context. Show us the rest of the picture to give us an idea how much you have cropped in.

Why? Because at f/2.8 the pictures you have shown COULD look perfectly acceptable depending on the context. Because f/2.8 is going to be soft and the closer you come to a 100% crop of the image, the more visible that softness will be.

For example, this image looks pretty sharp at this size:

However there are TWO THINGS that are going to make a 100% crop of this image look bad: 1) it was shot at f/2.8 and 2) the "context" of my 100% crop is going to be a TINY piece of the image:

Compare the above image and crop with the f/8 example I posted in the other thread:

and 100% crop:

Both sets of images shot with the Canon 70-200 lens. The first one at f/2.8 and the second at f/8. Both crops are 100% crops, but the first one the subject is far away, the second one is much closer.

Message edited by author 2009-01-21 08:52:03.

smurfguy

Sony SAL-1855 DT 18-55mm f/3.5-5.6

01/21/2009 10:25:16 AM · #9

Your phrase "near 100% crops" makes me curious. What is the process you used? If they're not exactly 100% crops, there will be softness introduced from the (up/down)-sizing.

I posted this elsewhere, but here're 100% crops from my Rebel XT + 24-105 and 5DII + 85.

Remember that there are a lot of factors that influence sharpness, the most prominent being depth of field (aperture), camera shake (shutter), and noise (ISO). Other factors are quality of lens, aberrations (ghosting, flaring, color fringing), and contrast of the scene. Try testing your lens with ample light (i.e. f/8, ISO 100, 1/400) so that you can eliminate DOF, noise, and shake as variables. Personally I get the best pictures when using a flash through an umbrella (as shown above), though you could also use shaded daylight.

The lizard shot appears to have an odd glow to me - like when you get out of the pool after opening your eyes underwater. The duck shot looks reasonable to me for handheld at 200mm, ISO 400, f/2.8, 1/100.

lawrysimm

Sony SLT-A57

01/21/2009 11:38:37 AM · #10

If it was handheld/monopod, my understanding is that to avoid camera shake you should use a shutter speed faster than the focal length of the lens. So for your bird shot at 200mm, your shutter speed was 1/100th... a shutter speed faster than 1/200th is realistically required to avoid camera shake. Of course this might require uping the ISO if you're already at max aperture which of course will introduce more noise.

Having said that, the lizard shot is at 1/500th so camera shake shouldn't be an issue on that one.

Message edited by author 2009-01-21 11:40:04.

shanksware

Canon EOS-5D

Canon EF 85mm f/1.2L II USM

01/21/2009 11:46:35 AM · #11

A 200mm lens at f2.8 has a DOF of a 1/3 of an inch at 6 ft.
Everything outside of that 1/3 of an inch gets soft, softer, softest.

Online DOF Calculator

lawrysimm

Sony SLT-A57

Sony SAL-1855 DT 18-55mm f/3.5-5.6

01/21/2009 11:48:48 AM · #12

Originally posted by shanksware:

A 200mm lens at f2.8 has a DOF of a 1/3 of an inch at 6 ft.
Everything outside of that 1/3 of an inch gets soft, softer, softest.

Online DOF Calculator

Nice link, thanks!

scalvert

Canon EOS-5D Mark III

Canon EF 24-105mm f/4.0L IS

01/21/2009 11:49:33 AM · #13

Also note that if you have a cheap UV filter or polarizer on the lens it can seriously degrade the image quality.

MAK

Leica M Monochrom

Voigtlander Ultron 21mm f1.8

01/21/2009 11:51:00 AM · #14

I had probs with my 70-200 f2.8 IS, you may just have a bad copy like I did, apparently (I did a lot of googling to find out why it was so soft) that lens I had had a few people claiming it was soft after 110mm at f2.8 and very acceptable from 70mm. My copy was exactly like this, I thought about calibration etc etc but after a long think I traded the lens and got an 85mm f1.2 that is tack sharp even wide open and I decided to purchase the 300mm f4 IS that is also tack sharp. I have a good friend who uses the 70-200mm f2.8 and has no issues at all with it, obviously it is not as sharp as the 300mm prime but totally acceptable and way way better than my copy.

good luck

smurfguy

Sony SAL-1855 DT 18-55mm f/3.5-5.6

01/21/2009 12:46:45 PM · #15

Originally posted by scalvert:

Also note that if you have a cheap UV filter or polarizer on the lens it can seriously degrade the image quality.

Ah yes, I forgot this. I used a closeup +3 filter on my 70-300mm, and quality sucked. It looked like I described before - like I was coming out of a swimming pool. That's sort of what the lizard shot looks like to me.

lawrysimm

Sony SLT-A57

01/21/2009 01:09:10 PM · #16

Originally posted by scalvert:

Also note that if you have a cheap UV filter or polarizer on the lens it can seriously degrade the image quality.

I didn't realise this... I've been somewhat disappointed with my pics and kept wondering what I was doing wrong (though I knew not to expect too much from kit lenses). But before I even used my camera for the first time I bought some cheap UV filters to protect the lenses so I've never really seen any pics without these filters on. It could just be the cause of my woes. Suppose that's what I get for paying a couple of quid on ebay for cheap UV's

dassilem

Nikon D90

Nikon AF-S DX NIKKOR 18-200mm f/3.5-5.6G ED VR II

01/21/2009 01:12:38 PM · #17

Originally posted by chromeydome:

I need to find this as when I look at the shot on my camera screen it looks sharp...then I put it on my pc and it is not....I must be messing it up in Raw

Ann

Olympus OM-D E-M1

Olympus 12-40mm f/2.8 Pro

01/21/2009 01:32:11 PM · #18

It might be the lens, or it might be technique. Test the lens in more of a "lab" environment. Pick a day that's not windy, put the lens on a solid tripod (don't extend the legs if the tripod's not really sturdy), use mirror lockup if your camera has it, and use a remote release or self timer, so that you don't shake the camera. Focus carefully, and take shots at various aperture settings. Then look at what you have. If it's soft, it's probably a lens problem. If it's sharp, it's your technique.

A lot of the time, shots taken with long lenses are soft because of bad technique, not a bad lens. It takes some practice to get a sharp shot with a long lens.

chromeydome

Nikon D7000

Sigma 10-20mm f/4-5.6 EX DC HSM for Canon

01/21/2009 01:35:37 PM · #19

Originally posted by dassilem:

Originally posted by chromeydome:
Are you doing any post processing of the raw image file before exporting to a jpg? A raw file is not suitable for direct use without pp.

Go into aperture and try a bit Definition slider, some Vibrancy slider and just a bit of Sharpening, then export another: you should see a big difference

Bear_Music posted a really good explanation about this in a thread just yesterday--hunt it down (I would do that for you but
I am typing this on my iPhone & my patience is insufficient :)

I need to find this as when I look at the shot on my camera screen it looks sharp...then I put it on my pc and it is not....I must be messing it up in Raw

Here is that thread--Bear's explanation of the RAW vs the jpg should be helpful in this context. (and the camera lcd image is not the raw puppy)

Dominic146

Canon EOS-400D Rebel XTi

01/21/2009 08:48:58 PM · #20

First of all I'd like to say thanks for all the advice everyone has given me on this. Now a few people have commented that it could be soft due to wrong technique. So I wanted to find this out myself if do have the wrong technique, even though shooting on a monopod with a shutter speed of 1/1000th should eliminate most bad technique. Also I know the lens is completely wide open at max zoom but shouldn't it be a little more sharp? Here are the results

Note: I don't use any filters on the lens at all

Thanks again

Message edited by author 2009-01-21 20:54:53.

smurfguy

Sigma 10-20mm f/4-5.6 EX DC HSM for Canon

01/21/2009 09:17:57 PM · #21

There's no wrong technique per se, but just trying to eliminate variables during the test shots. =)

Yes, I would expect that to be sharper. I still think you might try it slightly stopped down. I'd email Canon support about it and send it in - especially if it's under warranty.

One other thing you might try first, though. Does your 100mm f/2.8 or 400mm exhibit similar behavior in the same spot in the image? Could it be the sensor or something in the body?

Message edited by author 2009-01-21 21:18:48.

Dominic146

Canon EOS-400D Rebel XTi

01/21/2009 09:22:23 PM · #22

No the other lenses don't experience any of this softness. The 400mm lens was also quite a recent purchase and the sharpness on this lens is phenomenal. I know it is a prime, but I am blown away by how sharp it is. At a 100% it is still awesome

Message edited by author 2009-01-21 21:22:53.

dwterry

Canon EOS-1D Mark III