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DerekW
27th August 2008, 09:45 AM
For my sins I am only taking Jpegs - and using the Natural mode with the sharpness set +1.

However I am finding the image slightly unsharp when viewed on the screen, using Image Magic to correct for out of focus often by only a 1% correction I get a sharp image.

The situation occurs on both the 12-60 and 50 200 lenses and at various ISO settings and exposure settings (both shutter and aperture)

The question is - how much sharpening do you apply to images, is it via the USM filter or by another technique and do you re sharpen the image for different image sizes. I very rarely print to large image sizes, mainly small prints and or newsprint and web use.

Any comments welcome - not too much ridicule please <g>

theMusicMan
27th August 2008, 09:59 AM
Hi Derek - I too have the sharpening setting in-camera set to +1 by default. I always shoot in RAW and use Lightroom (and sometimes CS3) to PP images when required.

I find most of the 'keeper' softer shots (I still have way too many non keepers :) ) are when I have used the Sigma at the extreme of its range i.e. close to 500mm and I then have to apply some additional sharpening to the final image. Sharpening images for when they are to be displayed on the web should always be a necessity, how you do it is down to personal preference.

I now have Lightroom2 and have found the sharpening tool in that to be much improved over previous versions and particularly Lightroom 1.4. This coupled with the fact that I can now do selective sharpening, contrast, clarity, saturation and exposure amendments (rather than on the entire image) I don't venture into CS3 that often now.

However, when I do use CS to sharpen images, I tend to use a combination of the Smart Sharpen tool and the USM tool. I have created an action that I use to do this which I have automatically assigned to a fn key - so it's a single key press for me to activate the process used.

I have also found that the USM tool with a larger radius sometimes helps to remove 'window shooting' appearance when one has shot through glass.

andym
27th August 2008, 10:09 AM
Hi

I shoot in Raw nearly all the time so any of the Sharpening setting set on the E3 do not apply.
I develop in Silkypix and apply a very small amount of sharpening on the output image.
I then use Photoshop(elements6)to finish my image .I resize my viewing images normally to 1280x960 to fit my screen resolution.
At the end I use USM with settings as follows

Ammount=125
Radius=0.5
Threshold=4.

I use this as a starting point and adjust if I need to.

If posting on the web I will resize to 800x600 or there abouts and reduce the ammount/radius.

Remember I am not an expert but this seems to give me sharp images.

Ps remember any sharpening setting applied on the camera will not apply to the Raw image unless you use Master/Studio to develop that image in which case it will apply the in camera setting to you Raw file.

knikki
27th August 2008, 10:24 AM
I have all sharpening etc set to '0' (altough I have seen some comments that it is not a true zero setting) and shoot in RAW
I do some PP in Olympus Studio Master and some in CS2
If I add any sharpening, which is very rare, then is done via USM in CS2 and is only set to 10% radius 2 threshold 2 (might have to check that)

Jim Ford
27th August 2008, 11:17 AM
Bruce Fraser's statement that _all_ digital capture images are inherently soft and need sharpening, should be in a bold heading in red on every page of this site!

Sadly, I see many potentially good images in the gallery that desperately need sharpening. Many DSLR photographers mistakenly think that because they've paid a lot of money for an expensive camera and lens, it can't possibly produce soft images.

I have an E3 with 12-60, 50-200 and 50mm lenses. Raw images (which are unsharpened) are soft - very soft, out of the camera, with all lenses. There's nothing wrong with the camera body, it's just inherent in the process of digital photography.

There are many web sites with tutorials that describe how (and as importantly, why we need) sharpening - here's one:

http://ronbigelow.com/articles/sharpen1/sharpen1.htm

I now use 'Photokit Sharpen' for all my sharpening. It's expensive, but very good and very flexible. It can be downloaded as a trial.

Here's a review:

http://www.computer-darkroom.com/sharpener/sharpener_page_1.htm

Jim

(Did I mention that _all_ digital capture images are inherently soft and need sharpening?)

Jim Ford
27th August 2008, 11:23 AM
Hi Derek - I too have the sharpening setting in-camera set to +1 by default. I always shoot in RAW

Erm, my understanding is that you can set the in-camera sharpening to whatever you like - it doesn't have any effect whatsoever on raw images. That's why they're called 'raw'!

Jim

Jim Ford
27th August 2008, 11:31 AM
BTW, the optimum amount of sharpening (I _have_ previously mentioned that _all_ digital capture images are inherently soft and need sharpening, haven't I?), is dependent on the display device and final size the image will be displayed. An image on an inkjet at A3, A4 or A5, or monitor at 1024 or 800 pixels will all require different degrees of sharpening.

Jim

theMusicMan
27th August 2008, 11:33 AM
Erm, my understanding is that you can set the in-camera sharpening to whatever you like - it doesn't have any effect whatsoever on raw images. That's why they're called 'raw'!

JimHi Jim

Interesting. I just did a test by shooting the same shot on my E-3, three times but on #1 the Sharpening setting was set to -2, on #2 the sharpening setting was set to 0 and on #3 the sharpening setting was set to +2.

If I zoom in to 1:3 and compare each of the images, there is a marked difference in the RAW files I view within Lightroom2.

I might repeat this test later using the 14-54 when I can set up the E-3 on a tripod (which is in the garage at the moment!)

Makonde
27th August 2008, 12:21 PM
I don't know the E1 Derek but FWIW I've found with the E520 that it tends to produce soft images in JPEG (that are otherwise very faithful to the RAW versions), and it seems that some of the in-camera processing may contribute to this softness. I keep gradation set to normal and the noise filter to off, and I suspect that the reasoning goes something like this: the 4/3 sensor needs tweaking to reduce noise and improve dynamic range, so Olympus attacked that for jpegs by processing and in the process, detail is lost. There's an interesting review in ?dpreview of the E510 where they conclude that in an attempt to recover from the loss of detail, Olympus then cranked up the sharpening under the camera sharpness settings. With jpegs on the E520, I find I get clearer and less soft results by turning off anything I can think of that implies in-camera processing (hence my recent thread asking if there was a price to pay for image stablisation too). Then I found that if I actually reduced the sharpness settings by one or two notches things got clearer!

Then I gave up on jpegs, really, and am now shooting simultaneous RAW plus small jpeg. I skim though the files in small jpeg to determine the keepers, then save those RAWs and delete the rest from my hard drive straight away - alas, 95% of the pics I take are rubbish.

Jim Ford
27th August 2008, 12:25 PM
If I zoom in to 1:3 and compare each of the images, there is a marked difference in the RAW files I view within Lightroom2.

Hmm, maybe I've got it wrong, but my understanding of raw is that the camera records the data from each of the photosites from the sensor, straight onto CF card without any processing (but I think noise setting is an exception. I'm not sure - I need to mug up on this). The data doesn't even carry any colour information - just greyscale. It's up to the raw processing software to de-mosaic and interpret the data.

Jim

Makonde
27th August 2008, 04:03 PM
RAW - I'd like to learn more about this. I am assuming that the in-camera processing does take some decisions in writing the RAW file. Noise must be one of them - we have the NR for example, where a second 'black' pic is taken so that hot pixel info can be deducted from the 'real' image (as I understand it). That's not the same as the Noise filter, AFAIK. For the latter, we have the ability to adjust it in the RAW conversion in computer. For the noise reduction, we don't.

Then, what about image stabilisation? The info about camera vibration has to be applied to the info from the pixels is this done as the RAW file's being written, or is it another piece of coded camera info that is stored as an adjustment in the RAW file? We don't have a camera setting in Olympus Master's RAW development palette for IS....

So what else is done as the RAW file's written, guys?

Chillimonster
27th August 2008, 05:04 PM
Hmm, maybe I've got it wrong, but my understanding of raw is that the camera records the data from each of the photosites from the sensor, straight onto CF card without any processing (but I think noise setting is an exception. I'm not sure - I need to mug up on this). The data doesn't even carry any colour information - just greyscale. It's up to the raw processing software to de-mosaic and interpret the data.

Jim

That's how i understood it as well, and ican be confirmed by setting all of the settings way off the mark and looking at the JPG compared to the RAW.

In fact, as another, different, test i set the camera up to record mono JPG and set the camera to record JPG & Raw.

You get a Mono JPG and a Colour Raw, so the RAW data must go straight to the card unaltered from the sensor.

More investigation needed - off to test out some theories :)

Paulpp
27th August 2008, 05:22 PM
Interesting. I thought I understood how RAW worked but now not so sure. My E3 was recently set for -1.0EV for a particular set of shots. In Aperture the data alongside the Preview shows -1.0EV, but the adjustments settings do not show it i.e the exposure slider starts at zero. I can only imagine that (in Aperture at least) adjustments start from whatever was set in the camera? - if that makes sense. The metadata also shows -1.0EV

Jim Ford
27th August 2008, 06:07 PM
Then, what about image stabilisation?

I think image stabilisation is independent from the data. I believe there's a sensor that detects movement of the camera and moves the sensor to cancel the effect.

Jim

Makonde
27th August 2008, 06:11 PM
As I understand it, the RAW file contains the basic output from the sensor receptors and metadata - which would include the mono - natural - vivid stuff as well as contrast, sharpening, white balance etc.

But I'm not at all sure of those other things I've mentioned: noise reduction I suspect is done irretrievably before the RAW file's written (there is no trace of the second, dark image that's taken in order to process out hot pixels from a long exposure shot, is there?); noise filter I assume is part of the metadata (as you can adjust its level in subsequent RAW conversion either in camera or on computer); IS I am not at all sure about and it could be either....

edit: There's good online info about RAW files here (http://www.luminous-landscape.com/tutorials/understanding-series/u-raw-files.shtml) - and one of those who are cited is no less than Thomas Knoll of Adobe. But it doesn't answer all these questions. The wikipedia entry on RAW is also useful - and links to a pdf file from Adobe on 'understanding RAW' which I am just about to read...

Jim Ford
27th August 2008, 06:17 PM
You get a Mono JPG and a Colour Raw, so the RAW data must go straight to the card unaltered from the sensor.

I think it's not really correct to refer to 'a Colour Raw'. Raw data is just greyscale. Whether this data is interpreted as colour or B&W is determined by the subsequent raw conversion software. If you want a colour image, the raw converter takes into account that the greyscale data is recorded through colour filters. If you want B&W, it doesn't.

Jim

DerekW
28th August 2008, 08:54 AM
Thanks everybody for your comments, the link to Ron Bigelow's articles is very useful.

DerekW
21st September 2008, 11:53 AM
As a result of the responses on this thread and a serious investigation into and a purchase of Apple Aperture I have now started to take RAW images.

I now have a crisis of confidence as to how unsharp/soft the raw image can be and questioning the sharpness of the original image.

So as to rule out the camera and lens I would like to examine full size Raw files taken with the E3 and the 12-60 lens and or with the 14-54mm. The subjects I am looking at are leaves on a holly tree 15 feet away froim the camera and also a yucca flower bud stalk.

I would appreciate it is any one can direct me to some raw files on a website that I could download so as to compare with my results.

Jim Ford
21st September 2008, 04:48 PM
Hmm, 1800 Hrs Sunday and the light's starting to go.

If you can wait 'till next weekend - and assuming the weather's OK - I'll take some images of a holly at 15ft for you, and put it on this site. I'll do it on a heavy tripod and post unsharpened and images sharpened with Photokit Sharpener (expensive but _very_ powerful).

Jim

DerekW
21st September 2008, 04:51 PM
Thank you - I will be in Arizona then but I will be able to look at it on the laptop
although any raw file in which you consider the camera and lens to be performing correctly will do.

Again thanks

DerekW
21st September 2008, 05:39 PM
I think I have now cracked the problem - which I think was more to do with my understanding (or lack of) of Aperture

Thanks for your offer