P 6x7 for astrophotography

Is any one out there using the Pentax 6x7 for astrophotography?

The demand on the lenses, exceeds normal demands and I need help in selecting telephotos that will perform. Thanks

Greg: I've only used it for comets and a few lunar eclipses with so so results except for Hale-Bopp. I used my 300mm at f/4 for 30 seconds using Kodak PMZ 1000 color print, undriven, shot at 7000'elevation. I have yet to use my 600mm for this purpose but will when we get our next comet. The 600 has a 5.8 inch front objective, so it lets in a lot of light. It can be shot at f/4 but don't have any of the subject near the edge of the field; it's soft in that area wide open. SR

It is my understanding that Pentex will modify it's camera for astrop use by allowing very long exposures w/o drain on battery. Call them.

Hi Greg,

 

<p>

 

I use my P67 for astrophotography and I4m very satisfied with the

results. The 2,4/105 can be used full open, I4m testing the 4,0/200 in

the next time. For real telephoto I use an special adaptor for my

astrophysics refraktor. I have no good results yet, because of the

poor quality of my mount.

Ask me, if you have further questions

 

<p>

 

Rein

The Pentax 67 is used by a good number of astrophotographers. In

fact, many of the outfits specializing in astrophotography equipment

have various accessories for the P67 � and in some cases the P67 is

the only MF system they support. The 400mm lens is often used �and

highly regarded- but as is the 300mm, 200mm, and even the standard

105mm. The adapted P67 camera is owned and routinely used by various

astronomy pads & research centers (Australia, U.S., Canada, etc.).

If you are interested in basic �FAQ� sorts of things for

astrophotograpghy, Hutech offers such a link:

http://www.sciencecenter.net/hutech/techdocs.htm . As others have

noted here and elsewhere, if you are interested in doing much of this

you will probably want to have you camera modified; the battery-drain

modification runs from $80-300, depending on where it is done, the

turn-around time requested, how far the camera has to be shipped,

etc. For a run-down on what might be the most that can be done, and

the benefits of it, this site has a nice synopsis:

http://www.company7.com/library/ptxshtr.html . If you are curious

what a fairly elaborate setup -complete with astrograph, Telescope,

etc.- looks like (note: setups larger than this usually look as much

like an anti-aircraft weapon as a photography base), this site has

fairly descriptive pictures, and some commentary:

http://www.airdigital.com/astro_eqpt.html . You will discover that,

basically, if you do anything more than having the anti-battery-drain

upgrade, you will be looking at an investment that may be more

significant than adding another lens to your existing setup. That

said, there are several accessories on the market. For instance,

Stellar International in Texas has dual-bayonet mounts and �Stiletto�

assemblies (focusers) for the P67; see http://www.stellar-

international.com/mformat.html . Telescopic mounts and other

accessories for the P67 are offered by Williams Optics Team in

Washington; see http://www.williamoptics.com . Hutech, the people

mentioned above, offer a camera-to-telescope interface for the P67;

see: http://sciencecenter.net/hutech/ptown/medium.htm . An even more

expensive option is an actual astrocamera, and there are makers

offering this in the P67 mount; for a brief site, with a picture of a

functioning camera, see: http://www.koheisha.co.jp/e-

mspenta6701.html . Many sites feature a few pictures taken with the

P67. Last but not least, photographers/webmasters often acknowledge

the focusing problems they have gone through before settling in on

a �method� that works for them (one such site hinting at this, and

hinting more info will follow is: http://astrophoto.home.att.net ).

These comments, and those found in some of the links to the above-

mentioned website, are quite valuable.