Episode 034: Full Control! – Monochrome conversion (3)

monochrome convertedDownload the Video!
Download the companion file! (…if there is one…. ;-) )

In this last episode (for now…) about monochrome con- version I show you a way to get full control over the process of making a monochrome image.

I “decompose” the RGB image into three layers, each containing one of the three colour channels.
By adjusting the opacity of the three layers I mix the channels as with the channel mixer. But I have the full image as “preview area” and can change the values as long and often as I want.

Each of the layers can be further modified with the curves tool, other tools or partially masked off. Don’t forget to make a safety copy of the layer.

The image on the top of this page was done in this way. It’s an enhanced version of the one I showed in the video. I have added a masked red layer for the background and a bit red layer for all of the image. This version is in the files for downloading – just two layers more than in the video.

The challenge

You can use this technique in the current challenge. Do a monochrome conversion with GIMP, post the image in the meetthegimp.org photogroup at 23 and be sure to use the tag “mtg-monochrome”. The challenge ends March 31 1600GMT and I’ll draw a winner by random choice.


00:34 Introduction
02:50 The leaf picture again
03:26 The colour channels
04:40 Decompose
06:26 The colour layers
08:00 Mixing the layers
09:20 Understanding the layer mixing numbers
10:15 Examining the layers
11:57 Adjusting the layers
13:00 – Curves on the blue layer
15:00 – And a layer mask
16:50 Summary
18:50 The Black and White Challenge
19:30 – Slide show
22:36 The web-site
24:49 The End
TOC made by paynekj

Contact me!

You can leave your comments on this blog or write me a mail.

Creative Commons License This work is licensed under a
Creative Commons Attribution-Share Alike 2.0 Germany License.

15 thoughts on “Episode 034: Full Control! – Monochrome conversion (3)

  1. you made a mistake in the video, when you say that for average of the three layers it must be put 33% 66% and 100%. Thats not that way: the good way is putting the top layer to 33% the middle one to 50% and the one on the bottom to 100%.

    In this way, starting at the bottom one, it first have the 100%, when passing through the second one is 50% of each other, and in the third one it is a 33% for the top layer, and the lower ones have 66% to divide in equal parts (50% each) so 33% each one.

    You can do a test with the circles you draw, if you try to adjust the opacity when the result is gray is ok (that is with 100-50-33,333)

    nice screencast, it discovers me a thing or two about the gimp!

  2. Stimulating as ever and takes me back to my days in the darkroom. The challenge you have set is problematic in that I believe the sort of images we now go for are based not only on composition but also on colour and may not be suitable for converting to monochrome. Although it is great fun to convert from colour to black and white only certain images would make great photographs. In the old days composition was paramount and colour hardly entered into consideration.

  3. Thank you for another great podcast. I am a recent fan of yours and over the past 2 weeks I have watched all of your podcasts often while commuting to work. I appreciate the many tips I have gotten from your podcast it has made my adventures with Gimp easier.

    I have been in photography as a hobby for about 50 years now and the recent podcasts about black and white remind me of the early days for me as all was black and white due mostly to cost. I’ll be watching for shots I can take to convert to black and white.

  4. Pingback: intermayer.com

  5. Pingback: Meet the GIMP « Ang Pilipino GIMP

  6. Pingback: Kausch & Friends

  7. I hope the judging of the conversion was done by someone tempered with years of experience with real BW work in lieu of just digital experience.

  8. I have made a lot of images in the dark room before – but I don’t think this experience is very valuable for this. Looking at images is a valuable education – and thinking about what you like and why.

    I never achieved as good results in the dark room as I do now with the computer. To get a really good image in the dark room you need time, money and experience.

  9. I also spent many hours in the darkroom trying to produce the exhibition winning, monochrome print and that experience gained is most valuable in the digital manipulation of images. Also, in the production of the exhibition print, there was a considerable amount of hand finishing after the final printing stage. If you have ever tried to remove minor blemishes, such as dust spots or spots caused by faults in the emulsion, by ‘spotting’ with a camel hair brush and special liquid dyes, you would appreciate the use of tools such as Clone and Healing. Remember, the generally used film size was 35mm and prints were required to be about 500 mm X 400 mm often produced from only a part of the negative.

    Such experience, I would suggest, can be classed as “real BW work” and I have found it very difficult to find fault with Rolf. Indeed, I have been inspired to spend many hours, following and expanding upon his teachings, in my efforts to produce monochrome images from colour images using Gimp, which I would have been proud to have produced in my pre-digital days.

  10. OK. thank you for showing how to trun a Color Photo into BW.
    But what is the easyeast way around. How would be the best way to create a Color picture out of a BW Photo?
    Is there a way to tell GIMP what shade of BW is a certain color?

  11. Pingback: MTG: Обзоры выпусков за весь 2008 год! « Блог фотолюбителя :)

Anything to add from your side of the computer?