I'm also an amateur, and saying so reminds me of a little catchphrase I came up with a while back to help keep things in perspective. It goes like this: "I'm not a professional photographer, but I'm
very professional about my photography!"
:)
You can definitely achieve a good B&W conversion in Photoshop. Forgive me if I'm telling you something you already know, but I'll go on just in case this helps. There's several ways to achieve a gray scale image in Photoshop and some methods give better results than others. If you haven't already discovered the B&W adjustment layer in Photoshop, you should definitely give it a go. The comparison below shows the B&W adjustment panel in Lightroom but the B&W adjustment layer in Photoshop behaves exactly the same way. I'm using Lightroom here so that I can give you a side-by-side comparison of before and after. The beauty in the B&W adjustment layer (as opposed to simply de-saturating the color image) is that it allows you to adjust the luminosity, or degree of brightness, for all of the colors/channels (think tones) shown in the dialogue box. And being able to adjust the luminosity of individual tones gives you a great deal of flexibility for achieving tonal separation in your B&W's.
This is an image I purpose-shot for B&W conversion just this week, although I haven't quite yet fully realized how I want to process the image. But when I saw that red bike against that yellow wall I knew the scene had the components that I prefer in my B&W images, which in this case are two distinct and vivid colors (think tones) that would allow me to separate the colors (think tones) even further in post processing. When you look at the sliders in the adjustment panel to the right, notice the left end of each slider is darker and the right end of each slider is lighter. This only means that pushing the slider to the left will darken a given tone while pushing the slider to the right will lighten a given tone. You can see I've pushed the red bike toward black while pushing the yellow/orange wall towards white. So far I haven't gotten what I want out of this image but its a fine example of how to evaluate a scene for color/tone before opening the shutter. Comparing the reds and yellows in the original photograph to similar reds and yellows in the color chart I uploaded earlier helps to visualize each color's 'natural gray scale tone' before any luminosity adjustments are made.
