Asking for opinions

[garfield]

HI! I would like to ask you a question regarding 2 matters:

1. why is it that when you scan an image there appears some bright blue tint that makes the image brighter and better, but when you try to use curves on it darkens a LOT making the image uglier. So, does this mean that images scanned don't need to be retouched assuming that its bright already?

2. I know that sharpen tool makes a part of the image stand out from the image right? Why is it i read something that blur also does this too but is much better also? So which is which. I'm just a little baffled....

Thanks everyone for reading my post TY

[jeaniesa]

Hi garfield,

1. why is it that when you scan an image there appears some bright blue tint that makes the image brighter and better, but when you try to use curves on it darkens a LOT making the image uglier. So, does this mean that images scanned don't need to be retouched assuming that its bright already?

Can you post an example? It's very difficult to figure out what's happening from your description.

2. I know that sharpen tool makes a part of the image stand out from the image right? Why is it i read something that blur also does this too but is much better also? So which is which. I'm just a little baffled....

Sharpening doesn't necessarily make part of an image stand out. Sharpening essentially finds the "edges" in an image and makes the dark colors darker and the light color lighter along those edges. To the eye, this appears "sharper". However, if it is applied to the entire image, that doesn't necessarily make one part stand out more than another.

Blurring can make part of an image stand out if it's applied correctly. For example, let's say you have a snapshot of a child playing among his/her toys. The expression of the child is perfect, the the toys distract the eye from the child. In this case, you might want to select the child (or use a layer mask) and blur the background. The eye will then be attracted to the non-blurred part of the image (the child) and the focus will be on the child's expression rather than on all of the distracting elements (the toys).

Hope that makes sense.

Jeanie

[phili1]

Garfield.

I think you are talking about the top of the photo when you scan.

If that is it, then the problem is that your Photo is shifting from the top edge causes a blue reflection, because it is a reflection curves exagerates it.
If this is not what you mean the you have a color cast which must be removed before adusting with curves.

Sharpening. The idea of photography is to put emphisis on a specific image when takeing a picture of a specifiic subject, So the best way is to adjust your shooting to keep your subject in focus,( depth of field.) this does not make it any sharper but it fools the eyes because you only see that which is sharp. In photoshop most pros do not use the sharpen filter, they use the unsharp mask, this sharpens certain areas that give the illussion that it is sharper.
They in turn when they do not have time to adjust at camera depth of field use the bluring filter to accomplish the same effect.

Hope this is what you meant.

[garfield]

YEAH! thats what i mean when my friend scans the image there is the blue thing. So, i guess retouching a scanned image with either curves or levels is bad right?
color cast? uhm, what is that? I dont know...
actually i am not an expert so i still cant use unsharp yet so i still rely on sharpen edges or things below the unsharp filter.
So what phili says is that blur and sharp is the same right?? BUt blur is much easier right? i am just a little confused...

[phili1]

OK lets take the blue first. TEll your friend to use a pices of 8 x 10 card stock. place the phot in the left top corner put the cardboard over it and adjust it so it is tight in the corner. The problem is the picture is probobly not flat and it moves and the card stock will keep it from happening.

Blur and sharpen are not the same.

Take three items and place them in the same picture.
Item 1 boy
Item 2 goat
Item 3 barn
You want to take a picture of the boy and the rest is in the picture and all are sharp. With this all three catches the viewers eye and you want your subject to stand out, so you blur the goat and barn to put the emphisis on the boy. Thats called selective sharpening but it is really bluring.

Sharpening is when you have a subject and you did not focus proprerly and you want to see more detail in your photo, is when you use this. There is not anyway to sharpen an unsharp phot but waht it does it fools the eyes. It gives the ellusion that its sharp by sharpening edges. A badly out of focus picture cant be saved but slightly the results are awsome.

Hope that clears it up.

AS far as unsharp mask yopu do not need to know too much all you have to do is view it to adjust it.

For people a basis for adjustment would be as follows.

Amount between 80 & 125% - Pixels 1.0 to 2

Threshold between 0 & 1

Color cast. When you scan a photo sometimes it scans off color and picks up a color cast pink, or green, or yellow. so you need to get your self and after market Photoshop book to learn how to use the different tools, and what adjustment you can use. In order to use the different tutorials you have to have a knowledge of photoshop or you will get lost.

[garfield]

thanks for clearing up the issue between sharp and blur, last question, what if my friend already scanned the image then what can yuo do to enhance the image so it will be better. since you said curves cant do it, so i'm thinking what tool do i use...

[phili1]

Use the clone tool to take the blue out and then you should be able to use curves. If you down load the pic I can give you a better idea. Make the size of your pic 100K