Is it looking properly when opened ?
y usewd
The Summars aren't bad lenses, but they are eraly fast lenses so lter lenses are better. Summars and some Zeiss lenses suffer because newer optical glasses introduced the early 30's which make the glass quite soft, they scratch easily and are also prone to slight atmospheric attack. It affects Summars, Novars and some Tessars. So a lot depends on where the lenses have been used/stored as you'll find excellent examples and also poor ones and the effect is a soft diffused low contrast image.

So you can have a lens that's scratch free and looks optically perfect at first glance but has aged badly so is next to useless. My own Summar is fine but I have a Novar that's junk on an Ikonta, and another similar Novar that came with a shutter and a Tessar.

Ian