New adventure: oilpainting course fine art, classical realism

At last I found someone who teaches classical realism and........... she lives nearby. What a treat. Her name is Monique Eysink.
For the last couple of years, I took several online courses but I miss personal contact.
Next thursday, 2th of October 2014, is the first real lesson.
So I started to search for suitable subjects. Not easy to do, there are so many beautiful licence free photos on the internet. But it will be my first painting so the subject must not be too difficult to start with.

I downloaded several photos and I think I found the one I will use.
A citron, sliced.
Then I made a beautiful print of the photo to paint from, in the size of the painting. I do not want to start too small but also not too big, so I choose A4 size, 20x30cm.

Then I made a linedrawing to transfer to the piece MDF. I covered the MDF with a medium Grey colour several times.

With the help of my computer I made a image with 7 tones and painted a little study in a smaller size on a piece of MDF to practise these grey tones.

And last, today I took the photo of the citron and took from a lot of places colorswaps to see what colours are present on the photo.

What I always do with painting bontanical subjects with watercolor is to make studypages with colorsamples and I will do the same with these photos. So I will make a page with colorsamples with watercolor.

I already made 7 pages with all the colors of oilpaint I own. I glued on each page 7 pieces with 1vwhite and 5 different grades of grey  and painted on them with each oil paint color.
So I can see what the different colors do when they are painted over these greys.
Are they transparant, or opaque. Does the color change by the underpainting.
For the classical realism it is important to know if the color is transparant or opaque because colors are glazed over a grey toned underlayer.
These pages are with the colors red, blue and yellow. I did the same with all the other colors.