Convert Color Image to Monochrome

       The process of making monochrome printed photos from color negatives is very easy. Images can be easily imaged on a special darkroom paper or darkroom multi-level general-purpose paper.Convert Color Image to Monochrome

        The contrast adjustment of multi-level general-purpose paper will produce a good dark tone range on monochrome photos, which is sometimes no different from the photos obtained from black-and-white negatives.Convert Color Image to Monochrome

       If it is a color transparent film, this situation will be more complicated. In order to obtain a monochrome intermediate film by re photographing the transparent film on the high-quality film with burrs removed, two steps: overexposure and insufficient development are the key. Convert Color Image to Monochrome

       Then print the negative on regular monochrome paper in a dark room. If these steps are done correctly, you will get very good results.Convert Color Image to Monochrome 

        With the continuous development of digital imaging technology, there is now a better method to convert color images into monochrome. Convert Color Image to Monochrome

       First of all, no matter how the picture is obtained, whether it is ordinary film or digital camera, it needs to be input into the computer and saved as a digital image in RGB format.Convert Color Image to Monochrome

       Use Adobe Photoshop or other software with digital image processing function (both have similar conversion tools to convert color images into grayscale images). Convert Color Image to Monochrome

       As shown in Figure 1, at first, color images were scanned into Photoshop using a film scanner, and saved in RGB color mode. We can convert color digital files into grayscale images in the following methods (as shown in Figure 2).Convert Color Image to Monochrome 

1、 Four different conversion methods

       The quickest way to turn a color image into a monochrome image is to use the gray mode option, that is, select “image / mode / gray”. However, the biggest disadvantage of this operation is that all color information is removed in the conversion process, and the conversion results will vary according to different images.Convert Color Image to Monochrome

       In other words, the same amount of conversion and condition consistency in the process of color conversion cannot be guaranteed. Therefore, if you want to get good color conversion, try not to take this method.Convert Color Image to Monochrome

       Saturation method, or more precisely, dilute the color, that is, select “image, adjustment, hue / saturation”, as shown in Figure 2, move the moving slider of saturation from 0 to – 100, and then click “OK”. As a result, the image obtained is very similar to that obtained using a monochrome negative without a color filter. Convert Color Image to Monochrome

       At this time, the image tends to be smoother, which is equivalent to obtaining a completely different original color image with the same gray dark light (as shown in Figure 3). However, this method is not the best, so it is not recommended.Convert Color Image to Monochrome

       This method is considered to be the most perfect so far, that is, using Lab color for transformation. First select “image / mode / Lab color”; Then select mode / grayscale, and the color image will become a monochrome image.Convert Color Image to Monochrome

         In the channel palette, color information is contained in channel A and channel B. The lightness value is in the lightness channel (as shown in Figure 4). The highlight and image of the brightness channel appear in the form of monochrome. Convert Color Image to Monochrome

       This step is the biggest improvement over the above two steps, which is that it uses the lab color space, which has the largest color gamut, uses a large color space to match a small color gamut, and the lab color space is a color expression independent of the device, so it does not need to consider the changes caused by display conditions Change. Convert Color Image to Monochrome

       However, although this method is popular with most photographers, I personally think this method of color conversion is not the most appropriate. Here is a new method to convert color images into monochrome images.Convert Color Image to Monochrome

         Mixed channel conversion method. Select “mode / adjust / blend channel”, as shown in Figure 5, and select monochrome in the dialog box. The default values for this channel are + 100% red, 0% green and 0% blue. Adjust the 3 sliders to change the monochrome value of the image. In the mediation process, sometimes 100% red is the best choice. Convert Color Image to Monochrome

      However, as a common basic initial point setting, the channel will be set to: 60% red, 40% green and 0% blue. Adjust the 3 channels until you are satisfied with the color of the image, and then click “OK”. Try to bring the total balance to 100%, but this is not an absolute point. In my opinion, this method is the best way to convert color images into monochrome.Convert Color Image to Monochrome