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Tuesday 21st Bright earlier periods but becoming overcast. Set up the Manfrotto 500 head with the Kowa 884 telescope mounted.
I went back to the larger PA7 camera adapter which doesn't use the pancake lens. My intended target was the hedge at 95 yards. Then a helpful pony moved into view. Bringing fine texture and a mane for examining the finest detail.
I have cropped the centre of the picture to show how digital enlargement softens the image. Yet still a lot of detail is present. I am quite pleased with this result. 1200mm equivalent F/L, ISO1600, 1/500. [f/12]
As an experiment, I have just discovered that the G9 camera body cannot reach inward focus without an eyepiece in the Kowa 884.
I had the PA7's camera adapter with a T2 thread fitted into the camera body. For which I had a matching T2 to 1.25" adapter and a Kowa 1.25" adapter in the telescope.
This basically means that only subjects within a few yards of the system can be focused. It would need a much shorter camera adapter if it was desired to use the telescope as an externally focusable, telephoto lens. i.e. Single power, without an eyepiece or camera lens.
I even tried the 1.6x Kowa extender but it was still limited in its distance focus before the 884 failed to focus in the camera. No doubt shorter 4/3 Lumix to T2 camera adapters are available.
They are! I have just ordered a Baader T2 - Micro 4/3 adapter with 19mm detachable extender. That should get me into distant /infinity focus. From memory, the Kowa has a native focal length of 500mm. 500/88 = f5.6. Rather than Kowa's own figure of f/12 at 25x with the zoom eyepiece fitted.
If I can attach the G9 firmly to the '884, without the eyepiece, then I can use the telescope's focusing knobs. I should then have much brighter images but at a lower, single magnification. Obviously I can't remove the prisms from the telescope's optical path. Nor would I want to, of course. So it isn't exactly a simple optical train. But then [prime] telephoto lenses often have a large number of optical elements. Over a dozen. The zoom telephotos sometimes up to double that number!
They are! I have just ordered a Baader T2 - Micro 4/3 adapter with 19mm detachable extender. That should get me into distant /infinity focus. From memory, the Kowa has a native focal length of 500mm. 500/88 = f5.6. Rather than Kowa's own figure of f/12 at 25x with the zoom eyepiece fitted.
If I can attach the G9 firmly to the '884, without the eyepiece, then I can use the telescope's focusing knobs. I should then have much brighter images but at a lower, single magnification. Obviously I can't remove the prisms from the telescope's optical path. Nor would I want to, of course. So it isn't exactly a simple optical train. But then [prime] telephoto lenses often have a large number of optical elements. Over a dozen. The zoom telephotos sometimes up to double that number!
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