Trying to be objective

I looked at Yoshi a week ago and thought "He looks great, he's really finally put on some weight!" And then I tried to pull up comparison pictures. I think I had been doing some deluding myself. I wanted to feel like I had just made life better and better for him since I got him at the beginning of February. But honestly, he came to me in better condition than he was in at the end of March. I think he has gained some weight since then, but we still have a long way to go in both weight and muscle. 

Sales ad picture - Dec or Jan
Very few ribs visible, but also a kind of dark picture 

Feb 5th - the day I brought him home

April 5th - drying after a bath 
Not at all flattering lighting or position here, really emphasizing the ribs

April 9th 
Looking much better than only 4 days prior... think that was a lighting trick again

April 13th

May 10th 
Shot from further behind him than any other picture, making him look a bit downhill

So my attempts to be objective are a complete failure without pictures taken from the same angle with the same lighting with him standing on all 4 feet.

Lesson learned. Now that we're settled at our new place, I'm going to attempt to take monthly comparison pictures. At the same time of day, from the same angle, stood up in roughly the same position. I hesitate to call them progress pictures because I do want to try to be objective about the effects his diet, work, and other factors (massage, chiro, turnout etc) are having on him. I don't want to again assume that I am helping improve him when that may not actually be the case.