Ok so I took the SX-70 Sonar to Easter with the Fam loaded with my second pack PX100. The day was pretty overcast but still bright enough that you could wear sunglasses. Temperature was in the high 70's (degrees F). Learning the lessons from the first pack I kept all of the subjects (the Fam) close and focused on getting a good image. As you can see from the first image these conditions produced very good detail and the contrast is much better than the first pack. The light/dark dial was centered for all of the images.
This next image has the lens pointed in the direction of the sun and you can see that as you would expect the image is a bit more washed out. I did use Photoshop to darken the image.
Here is another image with no Photoshop adjustments (other than to make it look as close to the original as possible). The images after this show a few experiments adding body heat to the development.
This image was developed in my pocket and heat was added via friction from rubbing my hand over the image for about 30 seconds. The image is darker and has a slight red tone as we expect. The shadow detail tends to go away. This method also is pretty hard to control since you can't see what is happening when the image is in your pocket. I tried twice more to replicate this and both times the results were darker and more red.
I decided to test out my idea from the last post. I shot this image with the dial 1 tick toward the white side of the dial (giving more exposure). I placed the image in my pocket to develop, checking it every 5-10 seconds until I saw that the image was primarily showing yellow and brown tones yet still had some of the light blue tones from the protective paste. At this point I started rubbing the image between my hands creating heat. I was able to significantly darken the image yet keeping the red tones from showing up. I am going to practice this technique as it has thus far produced the best tones and contrast.