Astro-photographic Landscape

Check my images in the media section, you will see a couple of 4x5 widefield images shot on film.

I use a 4x5 camera for astrophotography. Nothing high magnification, just a normal and wide angle lens for expansive views of the sky on a big hunk of film. Been at it for decades. I enjoy the process so much awhile back I tried to get N.D. in the post above to design and fabricate a super fast lens just for astrophotography for me! Unfortunately it didn't work out. I don't do too much color, however I do hypersensitize Tech Pan for printing later in my black and white darkroom. Just last week I got a few more sheets done before it got too cold to be out here in November. So, I'm still doing it at least.

I'd like to do 4x5 sky tracking photography, preferably with a color film like Velvia or Ektar. A basic barn door sky tracker can be built at home, and is good for exposures of around twenty minutes or more, as I recall -- in simplest form, doesn't even need a clock drive, just turn the knob a quarter turn every so many seconds. With a wide angle lens, the inevitable mount movement from touching the tracker isn't a big problem; image rotation due to imperfect polar alignment is a much larger issue (and the main limiter on exposure length).

Now I'm getting tempted. A couple small pieces of plywood, a length of piano hinge, a piece of all-thread, and some minor bits and bobs (screws, knobs, a tripod screw and blind nut for a bushing) -- I've got a 105mm f/4.5 lens that doesn't quite cover 4x5 when focused at infinity, but a little vignetting is less important when you're more interested in nebulosity than leaf count. An object the angular diameter of the Moon (roundly half a degree) is quite visible with a "normal" lens (around 150mm on 4x5) -- I've got a couple images of the Moon with a 50mm on 135 film (one's in my gallery). That suggests objects like the Orion nebula, Pleiades, Andromeda galaxy (M31), ought to be reasonably visible with a normal lens, meaning a barn door sky tracking mount would be sufficient for a start.

I'm a newcomer to film photography, having spent the past year building my astrophotography skill and gear chest.
I've just received a T-ring for my OM2n and will put that into my 1000mm focal length newtonian to see what I can do with 30 or so minutes, guided on Carina nebula here in the Southern hemisphere. Its a good deal brighter than Orion (Mag 1.0 cv 4.0) so I'm hopeful of something decent!
I've read about hyper-ing film (there is a film astrophotography sub-forum on cloudynights forum) but I doubt I'll get into that. I have some iso400 colour film, and some 3200 ilford that I suppose will really get the job done.
Being used to stacking hundreds of images taken over 10 to 20 hours and multiple nights with my digital gear, I'm looking forward to the relative simplicity of a single exposure!
I'm also planning on putting my Mamiya Press on top of the newtonian for widefield views on 6cmx9cm.

I will certainly post whatever I come up with here, hopefully in the coming weeks.

I think you'll quickly find that the "relative simplicity" of a single exposure is vastly overshadowed by the difficulty of managing to keep a single exposure over tens of minutes (or multiple hours) accurately guided. Amateur astrophotography was a pretty rarefied hobby before digital technology!

Yes, and sorry if my post sounded dismissive! I'm sure it will bring its own set of challenges I had a couple of months with my digital set up where most nights I'd be very close to throwing the whole set up over the fence, and enough time has now passed that I'm up for another fight

Donald Qualls said:

I think you'll quickly find that the "relative simplicity" of a single exposure is vastly overshadowed by the difficulty of managing to keep a single exposure over tens of minutes (or multiple hours) accurately guided. Amateur astrophotography was a pretty rarefied hobby before digital technology!

Click to expand...

First go the other night and I think I see enough here to try for better. 30mins on Orion and Carina nebulas, the two brightest that I know of.
My coma corrector spacing is a looking way off, so much so that I think it did more harm than good. And it looks like the mount suffered some jitters, but I think once coma is accounted for the images will be much stronger.