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Thursday 15th July. Overcast in the afternoon after some earlier sunny periods.
I fixed the Manfrotto 500 head to a raised base allow a much greater distance for testing image sharpness.
After measuring the distances on Google Earth, I have labelled the image alongside. I think you will agree that the detail is very reasonable. The cool conditions are not raising thermal "mirages." Though brighter conditions would allow faster shutter speeds.
The most distant shores of my usual water birding lake are nearer than this. I have IS set. The video of this scene was even sharper. So why am I not getting sharper plumage on the water birds? Let us try a closer target more representative of the birds out on the water.
The second image [Right] is of a hedge at 95 yards. Resized from 5000 pixels to 1000 pixels in PhotoFiltre7. Note the much shallower depth of field with a nearer target. The fence wires are actually quite close to the hedge. Shutter priority.
Next image [Left] is cropped from 5000 pixels to 2350. Then resized to 1000 pixels for the blog. The blue cloth was placed to provide fine texture at the target distance. I'd say that this image is larger and softer despite taking great
care with focusing and using wireless shutter release. Cropping
increases the image scale. The focal point with the cameras is not the
same as visual through the eyepiece.
Next image [Right] I have fitted the Lumix 20mm f/1.7 pancake lens and reverted to the DA-10 filter thread adapter. This image is also resized from 5200 to 1000 pixels. Interesting that the image scale is much smaller but sharper. It seems the PA7 isn't the magical adapter after all. I wonder why?
Visually the view is crystal clear with all the detail easily visible in
the cloth at 25x. It would be very easy to see an ant or small fly on
the cloth at this distance. Not so using the camera. The 220 yard
distant grass actually looks sharper than the much nearer hedge to my
eyes. Something is amiss with nearer targets.
The last image [Left] is again with the pancake lens, Program mode and DA-10 adapter. Now the telescope has been zoomed to 60x. Wireless shutter release again. Pretty good, I'd say. The detail in the cloth is really quite good. So, I must be doing something wrong with the lens-less PA7 adapter at mid-range, target distances. But what? Is it the processing?
Next image [Right] I have fitted the Lumix 20mm f/1.7 pancake lens and reverted to the DA-10 filter thread adapter. This image is also resized from 5200 to 1000 pixels. Interesting that the image scale is much smaller but sharper. It seems the PA7 isn't the magical adapter after all. I wonder why?
Visually the view is crystal clear with all the detail easily visible in
the cloth at 25x. It would be very easy to see an ant or small fly on
the cloth at this distance. Not so using the camera. The 220 yard
distant grass actually looks sharper than the much nearer hedge to my
eyes. Something is amiss with nearer targets.The last image [Left] is again with the pancake lens, Program mode and DA-10 adapter. Now the telescope has been zoomed to 60x. Wireless shutter release again. Pretty good, I'd say. The detail in the cloth is really quite good. So, I must be doing something wrong with the lens-less PA7 adapter at mid-range, target distances. But what? Is it the processing?
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