Unsharp mask

For web-sized pics (I use 750×500 px) I tend to use a very small radius (0.2) and 200-250%, then apply it once and if nothing starts aliasing yet a second time, then fade back to where the aliasing started. Often some areas start aliasing sooner than others and you need to restore these with your original resize. One of many ways of doing this is duplicating your image before sharpening, then erasing the bits that went wrong (so the original non-sharpened resize shows through).

Thank you all.

Thank you for that advice but i dont use photoshop, i use Nikon capture Nx.

Ollie, in Nikon Capture 4.4, after having set the in-camera sharpening to none (RAW/NEF), for my D2x files I use the following standard settings:

ISO 100: 50%, 5%, 4
ISO 200: 50%, 5%, 8
ISO 400: 50%, 5%, 12

I haven’t installed NX yet, but probably the settings will be about the same.

After conversion to JPEG, I do some finetuning in Photoshop and as the last action a final unsharp mask (eg 130%, 0.4, 0).

Hope this helps.

Thank you for that advice but i dont use photoshop, i use Nikon capture Nx.

without complicating matters, I can recomend using Camera RAW with Photoshop and doing all the sharpening at the RAW stage in PS. It will take some proving, but when printing large images photos sharpened at the RAW stage look slightly better than images sharpened using USM
Just for your information the August Issue of Digital Camera Magazine did a really good article on digital sharpening with some free plugins too

Mark

Ollie have you ever thought about doing evening courses, join a photographic club maybe. Normally find this time of year there are loads of courses, from beginners to advanced. just a thought. Anna 😉

Yes, i am looking at doing an everning course.

There are also some excellent tutorials that can be found on the Internet. A Google search should bring up a few.

To my mind, as one who is just learning, the whole post camera processing business is not an easy one and depends very much initially on trial and error!! 🙂 🙂

Ollie have you ever thought about doing evening courses, join a photographic club maybe. Normally find this time of year there are loads of courses, from beginners to advanced. just a thought. Anna 😉

Thank you. It is all making sense now. Im going to have to have a play in a bit with this layers thing.

If I understand him correctly Paulc is suggesting having two copies of the image, one overlaid on top of the other.

Then you can rub out sections of the top image, to reveal the original, below.

Once you’ve finished flattening the image merges all the layers.

You don’t even have to have layers containing the same photo, you can layer all sorts of images, one on top of another to create a montage.

Simply copy what you want into the clipboard, then paste as a new layer. Grab it with the mouse, shift it where you want, change it then when you’re happy with it, flatten it and save it.

Can someone please explain this layers thing to me?

It is also a good idea to apply the USM to a different layer as if certain areas appear to be oversharpened they can be removed by just rubbing them out.

I have atached my first try. The second photo is the origional and the first i have applied a mask to. I would also be interested to see if i am doing it wrong or badly what others would do to the photo.

Cant really see any difference Ollie. :rolleyes:

I am no expert and have only just recently begun playing with post camera editing but I have taken your photograph and applied the following settings in Unsharp Mask:

Amount 150
Radius 0.3
Threshold 0

This was just a quick play this morning. I am sure that anybody who actually knows what they are doing could come up with better results! 🙂

I also had a quick general play and removed the dust spot and played with the colour a bit in the second photograph.

I have atached my first try. The second photo is the origional and the first i have applied a mask to. I would also be interested to see if i am doing it wrong or badly what others would do to the photo.

I find it enormously helpful when used with digital photographs that you want to view exclusively on computer monitors, and where the camera has a propensity to take pictures in soft focus. Many digital cameras have settings to control some of this in the camera.

I would not expect it to salvage an out of focus photo. Thank you all for your help. I will post some before and after photos for any more feedback later.

BTW: Most often I find that applying the USM (or some of the others – Sharpen, Smart Sharpen) with a very small settings several times does much better job than trying to fix the optimal parameters on a single run.

Thank you for that explanation. I will go and have a go at it tomorrow and put some results in this thread.

Ollie,

This advice I give to you as a professional – heed my words.

Unsharp mask is one of those tool which you use in a ‘as I see it mode’ A photo which is out of focus is not necesarily helped by this tool – a blurry photo is a blurry photo, you’ll never change it – it IS however exceptionally helpful when dealing with older photos or those that just aren’t sharp enough.

My best advice is to select a photo and ‘play’ with it – you’ll know when you’ve gone too far… Keeping the Threshold at 0, Start small on the radius – 0.5 px… then increase your Amount (top bar)… keep the ‘preview’ box checked and you will be able to see what is happening to the photo. If, by the time you reach an amount of ‘200%’ things don’t look that much better, back that off and increase the Radius and start increasing the Amount again. There is no magic formula to using Unsharp Mask, as no 2 photos are alike.

What ever you do, do no use the ‘dust/scratches’ tool… that has a tendency to remove too much detail – its a heavy handed ‘gaussian blur’ and removes toanl levels and detail – you’ll regret ever using it.

The samples I’ve attached (simply scanned – no colour balancing) will hopefully illustrate what I’ve said here. The first pic is untouched – simply scanned from the 4 x 6 print, the second has Unsharp Mask applied with a radius of 0.5 Pixels and an amount of 136%, the third has received 136% but at a pixel radius of 2 pixels. Download them and view them in sucession in Windows Media Viewer – you’ll be more able to notice the nuances in detail.

All effects of course are dependent upon the resolution of the image.

James