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Sorry its going to rain

Started by Rocket Pooch, Jul 13, 2010, 09:51:26

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Rocket Pooch

Hi,

Just took delivery of a Pentax 67 150mm F2.8 lens to go with my Zoerk adaptor, yipeeeee, now its going to rain for a week.  Adpator and lens £236.00.  I will be using the lens at F4 (QSI will not image at F2.8 with 1.25 filters, I think, but I'll check) giving approx 347x461 arc mins thats massive 8 arc seconds per pixel, by the way, it will be guided with the TS.  The big advantage of using a 6x7 lens is a) even with my QSi the CCD will only use the centre 1/3rd of the image circle and b) the back focus is approx 85mm thats more than enough to use on the QSI.

I'll get some images of the setup put together for the forum.

Chris

Mike

Pentax! Wow. I am looking forward to seeing what you can produce with that.
We live in a society exquisitely dependent on science and technology, in which hardly anyone knows anything about science and technology. Carl Sagan

RobertM

I hope it works out, Pentax are a very highly respected name and their lenses are considered some of the best.  I think going for a 6x7 lens is a wise move.  I've had a Pentax 50mm f/1.4 35mm lens which is supposed to be the d's b's for terrestrial but I found it just isn't sharp enough in the corners for astro unless stopped down to f5.6.  I also found the quality of adaptor makes a lot of difference too and Zoerk make some of the best so good choice there.

Are you going to try a tilt shift, should give a different perspective to those astro shots ;-)

Robert

Rocket Pooch

Definately not going to use a tilt or shift on it :-) I just got the 67 to t-male adaptor.

Chris