Quote:
Originally Posted by Rich Hibner
i think you need a different achromat.
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Hi Rich,
Dennis Wood (Brevis35 fame) suggested the issue might be the amount of zoom I needed and that a 72mm achromat could resolve the problem. It sounded logical (which is why I experimented with so many configurations myself). However, I see that the problem exists even when NO achromat is installed.
A couple of days ago I took a serious of photos with the camera through the DoF adapter using various zooms to see the effect. Basically I pulled the zoom all the way back, took a pic, zoomed in a notch, tool a pic, and so on:
http://i120.photobucket.com/albums/o...obar/zoom1.jpg
http://i120.photobucket.com/albums/o...obar/zoom3.jpg
http://i120.photobucket.com/albums/o...obar/zoom5.jpg
http://i120.photobucket.com/albums/o...obar/zoom7.jpg
http://i120.photobucket.com/albums/o...obar/zoom9.jpg
http://i120.photobucket.com/albums/o...bar/zoom11.jpg
Looking at this picture:
http://i120.photobucket.com/albums/o...35mm_no_fc.jpg
Plus this one:
http://i120.photobucket.com/albums/o.../HD_zoomed.jpg
(just the HC1 - there is no other lens or adapter attached)
Seemed to suggest the issue was with the HC1. However, I then compared to this pic:
http://i120.photobucket.com/albums/o...m_attached.jpg
I don't see any appreciable distortion in that last pic.
There is one major difference between the pics I can think of - the pic using the HC1 by itself with zoom is focused on a distant object. All other pics showing the focus "issue" are "close" focused. Hmmm...