“Hacking” Grain settings into ACR and more

Noise

While most people in this digital age seem overly concerned with noise, and mainly want noise reduction, I tend to like grain: It can really improve a digital image, and even make it appear sharper. Until now I had to simulate it using Photoshop for instance.

No longer: Recently, Adobe released ACR 6.1 and LightRoom 3. In these there was a new option added: “Grain”, with three controls: “Amount”, “Size” and “Roughness”. It produced some pretty nice “film like” grain. Way better then a simple “add noise” in Photoshop for instance.
That could be a time saver and simplify the workflow quite a bit.
Of course, I’d need to upgrade to LR3 for this feature. But, along with the mayor improvements in IQ due to the new demosaicing and processing algorithms (Process Version 2010) that would be totally worth it to me. Some of the other new features would be the icing on the cake.

One problem

I’d need a new Mac to run it: LightRoom 3 and PSCS5 only run on an Intel Mac, not on my Dual G5 PPC.
Since buying a new Mac just for this is a bit over the top, I decided to see what my options were.

A while back, Adobe updated the previous versions of ACR and LR to ACR 5.7 and LR 2.7: These versions also support the demosaic algorithm from Lightroom 3.
From what I’d read on the web, these should render the file as seen in Lightroom3, but not allow you to make changes to the new Develop settings, like “Grain”.

A bit more researching led (as often) to the excellent site of Victoria Bampton, AKA. Lightroom Queen. She had a bit more detailed info: ACR 5.7 should use the same Demosaic, and match the new additions closely. She also mentioned “5.7 can read LR’s settings but there’s no UI to change the new settings.” Sadly, LR2.7 will ignore the new LR3 settings. (Why Adobe, why?)

Then I got an idea when answering a question on POTN. Would it be possible to “hack” an .XMP file to only adjust the Grain settings?

The answer? It is!

Read the rest of this entry »

Pixels per inch for web

What is the significance?

Simply put? Nothing.
Well, if that were all I had to say on the subject, this would have to be my shortest blogpost ever… Okay, a bit more info then:
A lot of first time DSLR users are concerned that their shiny new camera delivers files that are “only” 72dpi, while their old point and shoot delivered 300dpi files. Why is this concern unwarranted? Surely 300 is more then 72, and more is better, right?

Wrong

The old wisdom saying is that “300dpi is for printing and 72dpi is for screen”.
There are a few things wrong with that.
First and foremost, the term “dpi” stands for dots per inch. In a digital file there are no dots, only pixels. So the correct term is pixels per inch (ppi).
Also, 72ppi originated as it was the resolution of an ancient Mac monitor. Current monitors have a much higher pixel density: My old 12″ PowerbookG4 for instance has a screen resolution of about 100ppi. Most current screens are somewhere between 80 and 120ppi.
Read the rest of this entry »

Photoshop CS4 Color Settings

Once, and for all

Never thought I’d blog about something as individual as PS Color Settings… Then again, there is so much conflicting, incomplete or downright inaccurate info on the web, I thought it might be time to set the record straight.

Individual

First of: Like more things in photography life there is no “Magic Bullet”. If that’s what you are looking for, better get used to this idea: You need a basic understanding of Color Management.
On the bright side: The settings in the Color Settings dialog box affect a number of things. However, unless done totally wrong, how your images are displayed is not one of those things.

Settings nobody should use

There is no “Magic Bullet”, but there is a “one size fits no-one”: The setting called “Monitor Color”.
Read the rest of this entry »

Black and White

What do humans see?

The human eye is most sensitive for yellow-green light. Take a look at the next gradient for instance:
Color gradient image

To me, indeed the green-to-yellow part looks brightest. Not so to Photoshop however.

About a hundred ways to lose the color

Well, maybe not thàt much, but quite a few anyhow. The easiest way (but offering zero control) would be to go through Image > Mode > Grayscale. That’ll give you this:
Gradient image converted to grayscale

Your image just became 1/3 of the original size, and that weight loss is caused because there’s now only a ‘gray’ channel instead of a red, green and blue one.
Big drawback of this method, is that it’s destructive: You indeed loose the color: It’s gone for good. Since you also have zero control, I’d never use this method.

Layers

So, we want something that’s reversible. Lots of ways to do that, using (adjustment) layers, but not all of them good… Let’s start off by naming just about the worst way imaginable: Desaturate. What this does, is that it removes all color information from an image, without the option for any user intervention. While that may or may not be important to you, this should be: All colors are treated as if they were equal.
While equality is a great thing, in this case, it isn’t, since to us different colors aren’t equal. Read the rest of this entry »

PSCS4, OsX and Epson…

part 2, not the best news

In my previous blog post about the subject, I mentioned a workaround for the bug, and also said I didn’t like the idea of converting to GenericRGB somewhere in the process since it might clip colors…

Gave it a quick try today, and yeah, it does clip “somewhat”…

Same image as last time. Original is AdobeRGB. In this image, some purples and dark blues are out of gamut for the R2880, using Epson Premium Glossy paper. Admittedly, not your “average” color palette, but one that does show problems if they are there.

Softproofed

Let’s start by showing the original converted to sRGB; Read the rest of this entry »

PSCS4, OsX and Epson…

don’t seem to play nice together.

When testing my Epson R2880 on PSCS4, it was quite obvious that something was off; The print came out looking nothing like the softproof on screen.

To give an indication of what it looked like: Here is a splitscreen: Top left is the softproofed image, bottom right is what the print looked like:
(screenshot converted to sRGB for web display: The difference is bigger in print)Softproof vs. print

The same image printed from PSCS2 was a perfect match to the softproof. Very weird.
I remembered that another photographer had complained to me about similar issues, and showed me some pdf files in preview. (In OSX you can preview a print as pdf file in Preview).

So I tried that. What a surprise: pdf generated when printing from PSCS2 was entirely different from the one using PSCS4. Same printer driver, same settings in Photoshop, same everything.
Neither of the pdfs looked even remotely like the respective prints by the way. The PSCS4 pdf looked like the softproof (as did the PSCS2 print).

Getting weirder by the minute.

A search on the net only brought up a “Double profiling” issue in OSX 10.5.something. Not what I was experiencing. Also, I’m running 10.4.11.

So, I decided to investigate further.
The pdf generated when printing from PSCS2, has an AdobeRGB1998 profile embedded. No idea why, since it is obvious the wrong profile (should be the paper specific profile for the R2880 I’d think, but that also isn’t the case)
Even weirder, the PSCS4 pdf, had a GenericRGB profile. What? Why on earth… That one has an even slightly smaller gamut then sRGB as far as I know…

Workaround

Some messing about testing with profiles followed.
It turned out that converting the PSCS2 pdf to GenericRGB, then assigning the paper profile, gave two identical images (easier to compare that way around, since the pdf coming out of the PSCS2 print path was very saturated and weird looking because of the wrong profile). Both were now again looking like the softproof in Photoshop.
So, doing the reverse (Convert to paper profile, assign GenericRGB) should give a decent print out of PSCS4. (at least, looking at the pdf. Haven’t wasted any paper on it yet).

So far for a workaround, now for the explanation…

Including “GenericRGB” in the search term proved to be a good idea. On the Adobe Forums I found a thread about grayscale printing (no wonder I hadn’t found it earlier).
In that thread Eric Chan explains how OSX Leopard will convert the image data to Generic Gray or Generic RGB before handing it off to the driver. So, yeah. That’s likely to screw things up…
I’m still not sure why or where the PDF out of PSCS2 gets an AdobeRGB profile. Seems rather silly if you ask me.

I might use the workaround when in PSCS4, or print from PSCS2 until this issue gets fixed… I think I’ll mostly use the latter, since I don’t like the idea of converting to GenericRGB somewhere in the process; it might clip colors without me having any control…
Have to compare a few prints, to see if there are differences.

Edit: The workaround does have its drawbacks: See my next blog post.

(Apple and Epson: Are you reading this?)

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