Quote:
Originally Posted by raymo
I do however, as I discussed with
another member in another thread, have almost perfect representations
of the lens' 5 leaf aperture diaphragm on the outer side of the brightest stars in my Orion image. The other member thinks it might be a reflection caused by the clear sensor cover, which is apparently very highly reflective. Has anyone else had this effect?
raymo
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To avoid the diffraction spikes caused by the aperture diaphragm requires the use of an aperture mask to stop down the lens rather than relying on the internal lens hardware. There are a number of lens filter step down rings available on eBay or you can make your own from sturdy plastic. I have successfully used this technique on my 200mm lens. I've had some success with my 50 and 100mm lens but I think I need to experiment a bit more with the diameter of the hole in the mask as I am still getting some coma.