Tom Kershaw
Subscriber
Buying a Summicron APO isn't going to improve your images if you are using a Craperon enlarging lens or a Junque 4000 scanner. And a Craperon enlarging lens and a Junque 4000 scanner won't do your Holga images any favors either.
This is a good point and one that doesn't get repeated sufficiently, and may be one reason people report poor results with materials or equipment known to work very well - there is a weak point or bottleneck somewhere. The process and "doing" of photography is a system after all.