Step 3 - Saving the high-bit scan in SilverFast Ai

This step is where we decide on whether we want SilverFast Ai to scan directly into Photoshop or to save the raw image as a Tiff file. There is no definitive "right" way, and so individual users will make the choice depending on their preferred workflow. Nevertheless, I prefer to scan the raw images to file and save them within SilverFast Ai. The following screenshot shows the necessary settings.

Select the General window and then choose Scan Mode. From the pop-up menu select Normal (File).

 

Saving the Raw scan out to file

 

Step 4 - Making the scan

From the Frame window select your scan resolution, etc. Unless you want to rescan the image again at some time in the future it's best to choose your scanners maximum optical resolution. Also make sure the Q-factor is set to "1" and that the Filter and Image Type are set for None and Standard respectively.

You can now press the Prescan button and watch the image appear on screen. Be aware that a full frame 35mm scan at 4000ppi is going to take upwards of 110MB of memory/hard-disk and so will be slow to appear. For the larger medium format scans, i.e. 6 by 9-cm the memory/hard-disk requirement is substantially higher. The last step before choosing the scan button is to crop your image. Make sure that you get all that you want into the scan frame. If the Prescan looks dark or even the wrong colour don't worry you cannot nor do you need to fix it, yet!

Finally, press the Scan RGB button and let SilverFast Ai and the scanner do their work. You will be prompted for a file name and make sure you choose to save the file in the Tiff format.

 

Prescan and Scan RGB Buttons

 

Configuring SilverFast HDR

To all intents and purposes SilverFast HDR operates in the same way as SilverFast Ai. On first opening SilverFast HDR you will probably be prompted to open an image, whether you choose to ignore this step or pick an image (any image will do) is pretty much up to yourself, but what comes next shouldn't be ignored.

Step 1 - Reconfiguring the SilverFast HDR Defaults

The first step in the set-up process is to switch off  any Filters that may be active.  Also check that  the Q-Factor is set to "1" as is shown below.

 

SilverFast HDR - typical settings

 

Step 2 - Setting the Gamma and Output Colour Space

For the purposes of this tutorial I will assume that you are intending to process positive type images scanned in SilverFast Ai and that these images have NOT been gamma adjusted; i.e. the for HDR output checkbox in SilverFast Ai that I mentioned earlier was left in the default unchecked or Off state.

Press the Option button and then select the General tab. For most users the Colour Model should be set to RGB.

The Gamma-Gradation should be set for a value between 1.8 and 2.2. Ideally the Gamma expected in 48Bit/HDR  should be left at the default of 1. The for HDR output checkbox is best left unchecked.

Note: The purpose of the Gamma expected in 48Bit/HDR insertion box  is to enable the user to insert the gamma value already incorporated into the image file. It is used to apply an inverse gamma curve which cancels out the gamma of the image and thus prevents the application of a double gamma adjustment. By way of an example - had you scanned your image in SilverFast Ai with for HDR output active and at a gamma of 2 you would need to insert 2 into the Gamma expected in 48Bit/HDR box.

Setting the Q-Factor to 1 in this dialog doesn't seem to effect what you choose on the main dialog, but it's better safe than sorry, set it to 1.

You should end up with the Defaults General dialog looking similar to that shown below.

 

SilverFast HDR Gamma-Gradation