ORDER to apply FILTERS for best results?

"mack" wrote in message

When I use Photoshop to spruce up photos from my digital camera I often apply:

Auto-Levels
Sharpen
Despeckle
Increase Saturation (10-20%)
Increase contrast and brightness
Adjust Levels (to chop off the upper and lower range when few pixels exist in those color ranges)
Scale (shrink to a more usable size for the web, email, etc.)

lets see.

1. Auto levels.
2. Increase brightness and contrast
3. adjust the levels <wait why did you just do 1 and 2 if you know how to adjust the levels? new first step #3.>
4. Increase saturation.
5. Change scale.
6. Despeckle if you must at this point.
7. Sharpen last…. if at this point you need to despeckle you have over sharpened. Go back in history and try a different sharpen level or method.

Charles
Torrance, California
http://www.tcpslashipdomains.com

mack wrote:

When I use Photoshop to spruce up photos from my digital camera I often apply:

Auto-Levels
Sharpen
Despeckle
Increase Saturation (10-20%)
Increase contrast and brightness
Adjust Levels (to chop off the upper and lower range when few pixels exist in those color ranges)
Scale (shrink to a more usable size for the web, email, etc.)

Don’t use Auto-levels, brightness and contrast. Do use Curves instead of Levels.

What I’m wondering is….
If I were going to apply all of those, in what order should I apply them? Should sharpen come before scaling, or after?

After

Should despeckle come before sharpening, or after? Etc..

After – the speckles will be easier to delete after they have been sharpened.

Should I over-sharpen before scaling down?

No, scale down first, then sharpen afterwards exactly as much as is needed.

I know that errors can compound. Doing a scale down, and then a scale up, for example, would be a really stupid thing to do. I assume doing multiple level adjusts is a mistake — like adjusting the contrast followed by auto-levels, then adjust levels. Are there other general rules like these?

Your intuition is good re multiple unnecessary scaling. There is very little degradation in image data from multiple adjustments. But with adjustment layers there is no need to do multiple adjustments, unless you decide it is more convenient.

I do not recommend use of the RGB master curve except for minor brightness adjustments. Use of the master curve in addition to adjustments of the individual channel curves can cause additional quantization as image data is passed through two look-up tables. Curvemeister avoids some of this quantization by using floating point intermediate results to generate a single LUT. The difference is subtle, and noticeable as more spikes and gaps inthe histogram.
—

Mike Russell
www.curvemeister.com
www.geigy.2y.net

I am going to have to disagree with you on the Curves instead of Levels argument. Most people who follow this instruction wind up using curve to simply shift the high value left, the low value right and the mid value diagonally up-left or down-right.

If you’re going to do that, you might as well use levels. Levels give you:

– A histogram to see what you are doing.
– The auto-option that does per channel nearly-optimal selection, before you start fine tuning.
– A much easier to use interface

Now, if you really need to do something impossible to do in levels, then by all means use curves. But, for most corrections, levels will let you do a much better job faster!

Mike

Demolisher wrote:

I am going to have to disagree with you on the Curves instead of Levels argument. Most people who follow this instruction wind up using curve to simply shift the high value left, the low value right and the mid value diagonally up-left or down-right.

If you’re going to do that, you might as well use levels. Levels give you:

– A histogram to see what you are doing.
– The auto-option that does per channel nearly-optimal selection, before you start fine tuning.
– A much easier to use interface

Now, if you really need to do something impossible to do in levels, then by all means use curves. But, for most corrections, levels will let you do a much better job faster!

Mike

Yes, if all you are going to do is move the endpoints of the RGB curve, you may as well use levels, but my point is that there is so much more that can be done for your images with curves.

For example, check out my recent tutorial on rescuing "misfortunate" images. In it I show examples of how curves may be used to save underexposed and faded images – the results are simply impossible to achieve with levels, but within the grasp of anyone who reads the tutorials and spends some time following the examples.

On your second and third points I also respectfully disagree.

Auto Levels is a fairly destructive thing to do to your images. About 2/’3 of the time it will improve an image. The other 1/2 of the time, when the brightest area of the image is not neutral, auto-levels introduces a bad color cast. In general, I would not recommend this as a starting point of any kind.

As with any change in interface, there is a little getting used to, but IMHO curves is not any harder to use than Levels.

It’s true there is no histogram in Photoshop. For $35US you can get a better histogram, and a lot more, in Curvemeister. There is also a wizard that steps you through highlight, shadow, and neutral – this is IMHO easier to use than levels and it will quickly and easily give you superior results on most images. From using the wizard you can graduate to using the curves interface directly.

Do try it out, whether using native curves in Photoshop, or buy following the tutorials using the demo version of Curvemeister. I think even beginners will find a new world of excellent images once they take a peek at curves.
—

Mike Russell
www.geigy.2y.net

The link to the misfortunate images tutorial mentiond in my previous post is:

http://www.curvemeister.com/tutorials/misfortunate/index.htm —

Mike Russell
www.curvemeister.com
www.geigy.2y.net

<snip>

It’s true there is no histogram in Photoshop. For $35US you can get a better histogram, and a lot more, in Curvemeister. There is also a wizard that steps you through highlight, shadow, and neutral – this is IMHO easier to use than levels and it will quickly and easily give you superior results on most images. From using the wizard you can graduate to using the curves interface directly.

<snip>

There is a histogram in Photoshop CS.

Clyde

On Thu, 24 Jun 2004 09:58:07 -0500, "Demolisher" wrote:

I am going to have to disagree with you on the Curves instead of Levels argument. Most people who follow this instruction wind up using curve to simply shift the high value left, the low value right and the mid value diagonally up-left or down-right.

If you’re going to do that, you might as well use levels. Levels give you:
– A histogram to see what you are doing.
– The auto-option that does per channel nearly-optimal selection, before you start fine tuning.
– A much easier to use interface

Now, if you really need to do something impossible to do in levels, then by all means use curves. But, for most corrections, levels will let you do a much better job faster!

Mike

Levels only lets you alter three points. Curves allows you to alter any point on the line. It’s much more flexible and ten times better than levels for any image.

Of course, it does require you to think and some work on your part and is, hence, not popular amongst casual users. 🙂

—

Hecate

veni, vidi, reliqui

..

Of course, it does require you to think and some work on your part and is, hence, not popular amongst casual users. 🙂

Curves are cool… but It is a foolish painter that discards all his brushes but one. Learn all the tools they are there for a reason and levels, brightness and contrast and Channel Mixer all have there places.

Knowing when they are appropriate is what makes you good.

Charles
Torrance, California
http://www.tcpslashipdomains.com

Agreed that curves are more powerful and functional than levels. Curves can pretty much do a large percentage of PS’ tonal and color correction tools. But it also takes a LOT of learning to master curves to get to that stage.

Mike Russell wrote:

Demolisher wrote:

I am going to have to disagree with you on the Curves instead of Levels argument. Most people who follow this instruction wind up using curve to simply shift the high value left, the low value right and the mid value diagonally up-left or down-right.

If you’re going to do that, you might as well use levels. Levels give you:

– A histogram to see what you are doing.
– The auto-option that does per channel nearly-optimal selection, before you start fine tuning.
– A much easier to use interface

Now, if you really need to do something impossible to do in levels, then by all means use curves. But, for most corrections, levels will let you do a much better job faster!

Mike

Auto Levels is a fairly destructive thing to do to your images. About 2/’3 of the time it will improve an image. The other 1/2 of the time, when the brightest area of the image is not neutral, auto-levels introduces a bad color cast. In general, I would not recommend this as a starting point of any kind.

PS’ Auto tools are intended for the users who pay $500+ for it but don’t want to spend the time and effort to learn how to take full advantage of it. Just like those who buy a Nikon F5 and use it like a point and shoot.

Having said that, just like the auto modes on a camera, PS’ Auto tools can get you the right or decent results most of the time. 2/3 of the time is not bad at all, especially if you don’t know how to set an exposure on a camera, or use curves in PS. For many, this is all they want.

Even for those who know how to use curves, PS’ Auto tools can be an excellent starting point. By trying out the Auto tools first, you can quickly get a sense of what kind of problems you need to fix in an image. If the Auto tool result is sufficiently good, you are either done or can use it as a base for further editing. If not, you can start from scratch, but with a good idea what you need to do.

In article <40daeba2$0$82603$
says…

I am going to have to disagree with you on the Curves instead of Levels argument. Most people who follow this instruction wind up using curve to simply shift the high value left, the low value right and the mid value diagonally up-left or down-right.

If you’re going to do that, you might as well use levels. Levels give you:
– A histogram to see what you are doing.
– The auto-option that does per channel nearly-optimal selection, before you start fine tuning.
– A much easier to use interface

Now, if you really need to do something impossible to do in levels, then by all means use curves. But, for most corrections, levels will let you do a much better job faster!

Mike

One thing in favor of levels is the ability to hold down the alt key while shifting the end points and see what areas of the image will be clipped.
I often do this to set white and black points, note the values and then cancel levels and use the same values in curves. I then adjust the curve shape to improve the midtones.

—
Robert D Feinman
Landscapes, Cityscapes and Panoramic Photographs
http://robertdfeinman.com
mail:

On Fri, 25 Jun 2004 09:09:59 -0400, Robert Feinman
wrote:

One thing in favor of levels is the ability to hold down the alt key while shifting the end points and see what areas of the image will be clipped.

Great stuff!!! I’ve been book looking for something like this for ages!

I don’t like Threshold because it’s based on Luminance (instead of composite RGB) so revealed extremes are "skewed" and cause clipping. This is because, in Luminance, individual channels are not represented equally but use a formula (roughly 10% red, 60% green and 30% red, if I recall correctly).

I asked once about "composite RGB threshold" but never got a response other than to use the Channel Mixer which is very cumbersome and I never really made it work for this purpose.

So, thanks! 🙂

Don.

Robert Feinman wrote:
[re curves versus levels]

One thing in favor of levels is the ability to hold down the alt key while shifting the end points and see what areas of the image will be clipped.
I often do this to set white and black points, note the values and then cancel levels and use the same values in curves. I then adjust the curve shape to improve the midtones.

I like this feature too. Curvemeister has a built-in thresholding function similar to that of levels.
—

Mike Russell
www.curvemeister.com
www.geigy.2y.net

On Fri, 25 Jun 2004 05:08:04 GMT, "Tabasco1"
wrote:

.

Of course, it does require you to think and some work on your part and is, hence, not popular amongst casual users. 🙂

Curves are cool… but It is a foolish painter that discards all his brushes but one. Learn all the tools they are there for a reason and levels, brightness and contrast and Channel Mixer all have there places.
Knowing when they are appropriate is what makes you good.

That’s true. However, for colour correction, I agree with Margulis – curves is the only way 🙂

—

Hecate

veni, vidi, reliqui

That’s true. However, for colour correction, I agree with Margulis – curves is the only way 🙂

What ever works best for you. However, I do a fairly mean job with levels. Of course I do use cures sometimes.

Charles
Torrance, California
http://www.tcpslashipdomains.com

What ever works best for you. However, I do a fairly mean job with levels. Of course I do use cures sometimes.

Argh! It has been a long week. It looks like I am to tired to post. Good Night!

Charles
Torrance, California
http://www.tcpslashipdomains.com

Tabasco1 wrote:

That’s true. However, for colour correction, I agree with Margulis – curves is the only way 🙂

What ever works best for you. However, I do a fairly mean job with levels. Of course I do use cures sometimes.

Charles
Torrance, California
http://www.tcpslashipdomains.com

Charles,

I used levels for years, then used curves and my stuff took a quantum leap. —

Mike Russell
www.curvemeister.com
www.geigy.2y.net

Sorry for the simple question but I am having troubles setting the white/black values in curves. I am guessing these values set some sort of anchor point and then you dabble with the curve to set the contrast. So, how do you set the white/black anchor values in curves?

Tia,
Chris

One thing in favor of levels is the ability to hold down the alt key while shifting the end points and see what areas of the image will be clipped.
I often do this to set white and black points, note the values and then cancel levels and use the same values in curves. I then adjust the curve shape to improve the midtones.

chris sussmann wrote:

Sorry for the simple question but I am having troubles setting the white/black values in curves. I am guessing these values set some sort of anchor point and then you dabble with the curve to set the contrast. So, how do you set the white/black anchor values in curves?

Chris,

The black/white values set the clipping percentages for auto "white balance". IMHO, although these auto functions generally provide an improvement in image appearance, for most images they introduce a color cast. For about 1/2 of images, this color cast is very objectionable.

As described in Dan Margulis’s book, a better way to set you white/black point is as follows (assuming you are in RGB):

1) use Image>Adjust>Threshold to find the darkest and lightest points in your image that are A) important to the image, B) are neutral in color. Not all images have both of these characteristics, but most do.

2) put an eyedropper point on both of these locations.

3) move the curve endpoints *of the individual curves* to make these values pure black and white, or just a few points lighter or darker than black. Do not use the RGB master curve for this purpose, since you want to avoid creating a color cast.

You have now set the shadow and highlight, which are the two most important manouvers for good color correction. The next step is to select a neutral point. In a nutshell, click on something you *know* is gray, then adjust the middle points of the three curves

BTW – curvemeister partially automates the task of setting shadow, highlight, and neutral, and makes it faster and more fun to do. Give the demo a shot:
http://www.curvemeister.com/downloads/cmdemo/index.htm
—

Mike Russell
www.curvemeister.com
www.geigy.2y.net

On Sat, 26 Jun 2004 19:23:07 GMT, "Mike Russell" wrote:

Chris,

The black/white values set the clipping percentages for auto "white balance". IMHO, although these auto functions generally provide an improvement in image appearance, for most images they introduce a color cast. For about 1/2 of images, this color cast is very objectionable.
As described in Dan Margulis’s book, a better way to set you white/black point is as follows (assuming you are in RGB):

1) use Image>Adjust>Threshold to find the darkest and lightest points in your image that are A) important to the image, B) are neutral in color. Not all images have both of these characteristics, but most do.

Ok, I understand this trick. I have found such point in my image. What I am not following is next.

2) put an eyedropper point on both of these locations.

I use the eyedropper from the tools or do I open Curves and use those eyedroppers?

3) move the curve endpoints *of the individual curves* to make these values pure black and white, or just a few points lighter or darker than black. Do not use the RGB master curve for this purpose, since you want to avoid creating a color cast.

So, let me guess, I set the points in RGB mode and then adjust each color on it’s own…?

Thanks,
Chris

You have now set the shadow and highlight, which are the two most important manouvers for good color correction. The next step is to select a neutral point. In a nutshell, click on something you *know* is gray, then adjust the middle points of the three curves

BTW – curvemeister partially automates the task of setting shadow, highlight, and neutral, and makes it faster and more fun to do. Give the demo a shot:
http://www.curvemeister.com/downloads/cmdemo/index.htm

Chris wrote:
….

2) put an eyedropper point on both of these locations.

I use the eyedropper from the tools or do I open Curves and use those eyedroppers?

Use the eyedropper from the tools. For photographs, I don’t recommend using the black and white eyedroppers in tools and levels.

3) move the curve endpoints *of the individual curves* to make these values pure black and white, or just a few points lighter or darker than black. Do not use the RGB master curve for this purpose, since you want to avoid creating a color cast.

So, let me guess, I set the points in RGB mode and then adjust each color on it’s own…?

Yes, absolutely. The RGB "master curve" is useful for small adjustments near the mid-tone, but very prone to adding a color cast to your image.

Once you’ve done that, the next step is to set a neutral point to get rid of the "colored plastic wrap" that covers almost every image.

Thanks,
Chris

Any time!
—

Mike Russell
www.curvemeister.com
www.geigy.2y.net

"Mike Russell" …

Mike Russell () wrote:

On your second and third points I also respectfully disagree.

Auto Levels is a fairly destructive thing to do to your images. About 2/’3 of the time it will improve an image. The other 1/2 of the time, when the brightest area of the image is not neutral, auto-levels introduces a bad color cast.

Ha
2/3 of the time it helps and 1/2 time it doesn’t?
Is this Photoshop Math or what?
nikki