16.07.2020 Shaprness testing continued.

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Friday 16th. It was a little brighter today. After an hour's fruitless searching I finally found the NON-CAPTIVE panning lock, thumbscrew for the Manfrotto 500 head. It had fallen on the floor unnoticed and rolled under a chair.

Then it was back to my raised viewpoint so that testing could continue. Again I had the Lumix 20mm F/1.7 "pancake" lens and the Kowa DA-10 camera adapter fitted. 

I tried Program, Shutter priority and aperture priority at the same distances as yesterday. I adjusted the telescope zoom lens from to 25-60 in the marked steps at each target distance. Taking a picture at each setting. I set the camera's image stabilization both on and off for a run of all the telescope powers.

Program had a struggle to focus through the telescope at 95 yards. The 20mm lens was visibly hunting [breathing] back and forth. After I reset the focus with the telescope controls knobs things settled down gain.

More distant [200+ yards] images still seem to do better than half that distance. Could it be the pancake lens focus setting? There is a clear sharpness advantage to having the lens in place. Rather than the "naked" PA7 adapter. The question is where in its focus range does the 20mm lens want to be? Manual focus throws up a scale in the viewfinder from infinity to macro. This responds to turning the focus ring on the lens itself.

Visually the Kowa is delightfully sharp at all power settings and all distances. Bringing the camera into play is reducing sharpness but I still don't now why. 

My original Lumix G9 images are 17MB nominal, Fine, 8.7MP, 3:2 format, 5184x3456 pixels.

Short range at 18m or 20 yards cropped image at 25x.

The images look excellent taken at 200 yards at full screen on my AOC 27" monitor. The tall pale grasses at 220 yards look detailed and nuanced. While the hedge at 95 yards is not quite as crisp as I would like. This suggests a focusing issue with nearer targets.

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