I've just spent the day shooting small, table-top objects on a white, coved background.

I'm getting banding on the white background where it graduates from grey to black.

How can I tell if the banding is in the image or if it's just the display?

The images are all Hasselblad 39Mp Multi-shot, processed in Flexcolor as 16bit TIFFs.

I then make some further adjustments in ACR4.

In both ACR4 and afterwards in CS3, the banding is visible.

I'd just like to calm my nerves!

Thanks.

D.

ps. I'm not in a position to make a proof print over the weekend.

Push the exposure in PS and see if it gets worse.

In PS, on the Info palette at the right hand side there is an eyedropper; right click on it and change the display to HSB.

Now, move the cross hair over the banding part and watch B(rightness): if it changes, while you move the cursor and the display does not change, then buy a better monitor (though it might be the brightness/contrast adjustment).

However, if B does not change continuerly but several units at once, then the banding is in the image. Post one of the raw files indicating the location of banding, and the adjustment parameters, and let's take a look of that.

Make a new blank image. Assign the monitor space to it. Fill it with a grayscale gradient. Grayscale banding should now be diagnosable.

Edmund

Cheers guys. I knew I could rely on you lot!

Two observations........

1. In HSB, the % drops smoothly downwards as I move from light to dark.

2. (Perhaps I should have tried this first!) If I enlarge the image in CS3 (or ACR4) to 25% or greater, the image is as smooth as glass. Don't know if this is proof that the image is OK (as it seems to be) but I thought I'd mention it anyway.

Maybe I need a new monitor.

I certainly need a knew computer. This one is groaning under the weight of these massive files.

Thanks again.

D.

ps..........

Edmund,

Just tried your trick.

I've got a greyscale gradient (upside down. i.e. Dark at bottom) and banding is clearly visible.

So, it's the monitor.

Right?

D.

Right. Well, it is either the monitor or its callibration.

Cheers,
Bernard

Make the gradient side to side, give it more space to see how bad it is.
Better monitor calibration software is a good idea. Calibrations have less bands when they are closer to the monitor native color temperature, or when you use a monitor with built-in LUTs and more internal bits. I would suggest a monitor with internal LUTS anyway, especially if you're on a PC. Someone here will make a suggestion, Eizo and NEC are good.

The best calibration software is Basiccolor or ColorEyes, they both have fully functional demos so I recommend you go for one right away. I use Basiccolor.

Edmund

Edmund

This was the most important information you gave.

Now make another test: reduce the image size to that size, which shows the banding, but now with resizing, i.e. true size reduction, with the method PS suggests. I guess the banding will go. The reason is, that the on-the-fly size reduction is rather course compared to the resizing algorhytm. This means, that the banding is an artefact of the display method.

Edmund,

I use basICColor. Fabulous software!

But, the monitor is DELL - a tad old and probably well past its sell by date.

Thanks.

D.

Sorry, not sure what you mean by this. "....with the method PS suggest." ??

Thanks anyway.

D.

Go to Image, Image Size, change the units to percent from pixel, and enter for example 12.5%.

The resampling method can be chosen from a list at the bottom of this dialog. Leave bicubic sharper, which is suggested for reduction.