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Tim A.
super member
Reged: 09/19/07
Posts: 103
Loc: 40 30'55.0"N 105 3'19.0W
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Ladies and Gentlemen  ,
I'm about to embark on a large challenge for which I am ill-prepared, and I can use all the help I can get.
I have landed a top quality 4x5 aerial camera. It has no adjustments beyond exposure. That is, the focused is fixed at infinity, and it has none of the "usual" 4x5 camera movements. It is, basically, a brick with a lens.
Oh, and a fine lens it is. A Schneider convertible, at 150mm f/5.6 and 265mm f/12 (I think), depending on how you configure it. This is a sharp, contrasty, fast large-format lens. Mounted in a brick.
OK. So. I intend to lash this puppy to a motorized Celestron CG5 mount to take some, um, shall we say "very long exposure" wide-field astronomical photographs of (one would hope) top quality. I have all the incidental necessaries, like film holders, due to my alternative expensive habit, which is large-format photography.
But (and unlike my own, it's a very big but): I am a brash beginner in this. I have never tried astrophotography of any kind, much less of the large-format kind.
I can foresee so many issues. Some I am confident about managing (like, say, polar alignment). Others I'm not so sure about.
It would seem that reciprocity failure would be a huge issue. Likewise (and partly due to reciprocity), film choice must be crucial. There must be scads of other "gotcha"s lurking about.
And I'm a neophyte, a newbie, a sophomore with Ph.D. dreams. 
First: Has anyone you know ever tried 4x5 astrophotography? Have you? If so, that person (you?) is the person I need as a mentor. If not ... dang. Well, if not, whatever advice you film astrophotographers have to offer will be gratefully accepted.
And really, how many times in your life is your advice really welcome? 
Tim
Colorado
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Starbuckets 12.5" Dobsonian
Celestron CPC800
Celestron CR-150 HD on CG5-GT
Meade Starfinder 6" f/8
Oberwerk Deluxe II 20x80
Oberwerk Ultra 10x50
Celestron Regal LX 8x42
"Me? Crazy? Oh, yeah. Crazy like an ox!"
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ZachK
professor emeritus
Reged: 08/21/05
Posts: 667
Loc: Israel
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There is an article by Suk Lee on LF astrophotography. I have not done any yet but am working up to it slowly. It seems like if you have the camera and mount it would be worth a try.
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Zach Kessin
Yesha Israel
Meade ETX 127 Mak-Cass
15x70 Celestron Skymaster Binoculars
Sinar F 4x5 view camera
Rolliflex Camera 80mm F2.8
Pentax K-1000 Camera 35,50 and 60--300mm zoom
3 kids, Large cat, small dog
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mlcolbert
sage
Reged: 11/15/07
Posts: 353
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Tim Hi!
like you, another novice, I will be working with film and plate glass, in a lunar and planetary camera and experimenting with using a 4x5 body as well. They will soon be attached to a 130. Looks like we will haveto chase up Zach's suggestion re Suk Lee's article. Keep in touch!
michael
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zeiss
APQ 130/3x500 mm Telephotos/2xMC80/MC35/5x7 back/lunar and planetary camera
Hasselblad
503cw/500el/m
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Nightfly
super member
Reged: 06/20/07
Posts: 199
Loc: Sullivan, Maine
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Kodak E200 is available in 4x5! At F/5.6 try at least 30 minutes to an hour exposure if you have dark skies.
Good Luck!
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Jim Cormier
Sullivan, Maine, USA
www.nightfly.zoomshare.com
Pentax 67 with 55, 105, 165, and 300mm lenses
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AstroBobo
sage
Reged: 07/04/07
Posts: 395
Loc: Zagreb, Croatia
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Film flatness could be a problem. But try one exposure first, to decide if you need a vacuum holder.
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Boris Stromar : AD Infinitum member : Zagreb, Croatia, Europe
P75SDHF : P105SDP : MN71 : CGE : STL-11000
http://www.astrobobo.net
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ZachK
professor emeritus
Reged: 08/21/05
Posts: 667
Loc: Israel
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They make E200 in 4x5? I've never seen it, where can one get it?
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Zach Kessin
Yesha Israel
Meade ETX 127 Mak-Cass
15x70 Celestron Skymaster Binoculars
Sinar F 4x5 view camera
Rolliflex Camera 80mm F2.8
Pentax K-1000 Camera 35,50 and 60--300mm zoom
3 kids, Large cat, small dog
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Nightfly
super member
Reged: 06/20/07
Posts: 199
Loc: Sullivan, Maine
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Your right, my mistake. E200 is not available in 4x5. Too bad, that would be awesome if it was.
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Jim Cormier
Sullivan, Maine, USA
www.nightfly.zoomshare.com
Pentax 67 with 55, 105, 165, and 300mm lenses
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TxStars
sage
Reged: 10/01/05
Posts: 410
Loc: Lost In Space
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Here is what you need:
http://www.freestylephoto.biz/sc_prod.php?cat_id=1303&pid=773
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Tak FC-50
Tak FCT-65
Tak FC-100
"SCUZZO" 300/1.1
Camera Nikon F2 / Mamiya press 6x7 ,6x9 yay Film
Lenses Yes Many - lol
Mount - GoTo by hand and eye
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Suk Lee
Post Laureate
Reged: 10/07/03
Posts: 4315
Loc: Pleasanton, CA
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Yes, I've done it (E100) on 4x5. The size of the transparency was just mind-boggling. I had a vacuum back but sold it.
It was an amazing way to do wide-fields, but the lenses are really really slow.
Suk
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http://www.siliconvalleyskies.com
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Tim A.
super member
Reged: 09/19/07
Posts: 103
Loc: 40 30'55.0"N 105 3'19.0W
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Suk,
Thanks for the encouragement! Your experience with 4x5 gives me some hope!
When I came across a 1950's vintage Linhof 4x5 aerial camera, I couldn't pass it up. It has a 180mm f/5.6 Symmar lens in a Linhof shutter. It will at least be a good counterweight on my 6" refractor, to help get me off my knees when I'm using the beast. 
Anyway, I should probably stop that Symmar down to at least f/8. Some refractors in use for astrophotography are near that focal ratio, which makes me think it's an aperture I can work with.
Given f/8 and E100 film, I'm trying to guess some trial exposures. Any starting points you could suggest on that front? Most film astrophotographers aren't using E100, which sort of leaves me in the dark (no pun intended).
You had mentioned you used a vacuum back. Do you think that's essential? Obviously, if the film shifts during the exposure, that would be a bad thing. But I think it's unlikely I can find a vacuum back, so I may just have to think of a way to wedge a sheet of film in a regular holder in such a way that it won't move.
I don't think film buckling should be a big issue, unless E100 has a really thin base. I work and live in a generally very dry climate, so humidity is not an issue.
Any other advice you might have would be much appreciated! I'm excited to give this a try, and I hope to not burn through too much $$$ film in my learning curve! 
Tim
Colorado
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Starbuckets 12.5" Dobsonian
Celestron CPC800
Celestron CR-150 HD on CG5-GT
Meade Starfinder 6" f/8
Oberwerk Deluxe II 20x80
Oberwerk Ultra 10x50
Celestron Regal LX 8x42
"Me? Crazy? Oh, yeah. Crazy like an ox!"
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jgraham
Postmaster
Reged: 12/02/04
Posts: 5370
Loc: Dayton, Ohio
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Way back in the late 1970's and early 1980's I did quite a bit of photography using 4x5" sheet film (mostly Tri-X) on several homebuilt cameras along with a fore-runner to the Graflex from ca. 1905 (I had to cut down 4x5 sheets to fit the metric film holder). This was a neat format to work with and was particularly well suited for patrol work. Developing the film was a bit messy; I didn't have a developing tank for sheet film so I procesed it in open trays in a dark room (I evem did roll film that way until I 'discovered' developing tanks). After a while I replaced my 4x5" film backs with a Polaroid film back (cut from a camera I picked up at a garage sale) which let me use ASA 3000 speed b&w self-developing film. Now that was an interesting (if grainy) format to work with.
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-John
================================================
Homebuilt scopes from 4.25-16.5"
Meade LXD75-N6/SN6/SC8, DSX-90, ETX-60BB, ETX-125PE, DS-2130
Orion StarBlast, BinoViewers, Coronado PST
Rebel XT/XTi, DSI Pro (I & II), DSI, LPI, Electronic Eyepiece, Phillips SPC900NC
Tasco 60mm Refractors
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Suk Lee
Post Laureate
Reged: 10/07/03
Posts: 4315
Loc: Pleasanton, CA
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Quote:
But I think it's unlikely I can find a vacuum back, so I may just have to think of a way to wedge a sheet of film in a regular holder in such a way that it won't move.
I tried a shot without a vacuum back, and got a soggy out-of-focus mess in a 20 minute exposure. However, it gets pretty damp where I am at night, so I had no choice.
Your mileage may vary!
At f8 you can probably start with 10 minutes and easily go to 40 without running into sky-fog issues. At 40 minutes if you get short streaks instead of pin-points, it could be your frame shifting - 4x5 cameras aren't made to be held at the funny and shifting angles of long-exposure photography. I never had a problem with that but my Linhof is built like a tank.
Cheers,
Suk
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http://www.siliconvalleyskies.com
Edited by Suk Lee (04/27/08 04:16 AM)
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ZachK
professor emeritus
Reged: 08/21/05
Posts: 667
Loc: Israel
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I am hoping to do some LF astro work, I have a bunch of extra film holders and plan to convert 2-5 of them to vacuum backs. (Yea for cheap film holders from Ebay). That will probably be for 2009, for '08 I will stick to 35mm and 120 format. If nothing else on the 35mm I can get a pretty good shot at 2-3 minutes which is what the mount I am working on will probably be able to do. (Fork mount on a eq-platform, if I can ever get it built)
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Zach Kessin
Yesha Israel
Meade ETX 127 Mak-Cass
15x70 Celestron Skymaster Binoculars
Sinar F 4x5 view camera
Rolliflex Camera 80mm F2.8
Pentax K-1000 Camera 35,50 and 60--300mm zoom
3 kids, Large cat, small dog
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Tim A.
super member
Reged: 09/19/07
Posts: 103
Loc: 40 30'55.0"N 105 3'19.0W
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I thought a little bit about how to convert a standard 4x5 film holder into a vacuum unit, but I haven't come up with a good design.
It seems like it should be possible, and I'm curious about how you plan do it.
-- Tim
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Starbuckets 12.5" Dobsonian
Celestron CPC800
Celestron CR-150 HD on CG5-GT
Meade Starfinder 6" f/8
Oberwerk Deluxe II 20x80
Oberwerk Ultra 10x50
Celestron Regal LX 8x42
"Me? Crazy? Oh, yeah. Crazy like an ox!"
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ZachK
professor emeritus
Reged: 08/21/05
Posts: 667
Loc: Israel
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Check out this link http://www.magnachrom.com/MCHome.php they had plans in issue #5
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Zach Kessin
Yesha Israel
Meade ETX 127 Mak-Cass
15x70 Celestron Skymaster Binoculars
Sinar F 4x5 view camera
Rolliflex Camera 80mm F2.8
Pentax K-1000 Camera 35,50 and 60--300mm zoom
3 kids, Large cat, small dog
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Achernar
Post Laureate
Reged: 02/25/06
Posts: 3721
Loc: Alabama, USA
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I used to develop 4x5 sheet film all the time in trays. It was easy to so and as long as I first presoaked the film in a tray of water first and kept the emulsion side down, I never had scratching problems in the hard rubber trays I used. They have very slick and smooth bottoms and keeping the temperature of the chemicals around 68 degrees helped a lot preventing the emulsion from getting too soft and easily damaged. The film I developed most of the time was you guessed it, Tri-X. I think it was one of the best black and white films ever made, at least for general photography. It worked for me fairly well for astro photography either, considering the fact it was never intended for it. As for trying astrophotography with a 4x5 camera, I did once and found one major problem to watch out for, the film bowing or shifting in the holder. It recorded light just fine, but every shot I made was ruined because the film slumped in the holder and the center of the negatives were badly out of focus. Your lens can dew over, which also ruins your shots, so you will want a dew cap and heater strip to keep the lens from fogging up. Also, at F/12, you will have some insanely long exposure times, but then again you won't be fogging the film from sky glow unless you expose for an hour or longer. Unless that is, a light shines right into the lens, in which case your picture is ruined and you will have to take it again.
Taras
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10-inch F/4.5 Discovery Dob
6-inch F/8 Homebuilt Dob
4 1/4-inch F/4 Homebuilt reflector
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rlc
Vendor (Robert Clark Optical Glass)
Reged: 09/28/07
Posts: 6
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Wonderfully pleased to stumble onto this group. I have been, off and on, fooling with 4x5 film work for years. Had this material been available I would have made much more progress.
Recently move from a moderately poor sky area to a moderately good sky area. Have set-up pull down tarps to shield local ambient light and a concrete topped table for the mount. (Pretty good barn door).
Have been using TMAX 400 film. I suspect that may be a mistake. My home made camera is abt 8 inch fl and f5.6. Images are pretty good over most of the film but, at the edges, there is some coma. My exposure limit seems to be about 20 mins. I think I am being limited by rec limit. I intend to try a different film (what?) and going down to abt f8-9. (Different expiriments). I'll report to this group re what, if anything, I learn.
Bob Clark
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Nightfly
super member
Reged: 06/20/07
Posts: 199
Loc: Sullivan, Maine
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It would be interesting to see what you come out with. Medium and large formats are the final frontier for film. Good to have another analog man with us.
Jim
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Jim Cormier
Sullivan, Maine, USA
www.nightfly.zoomshare.com
Pentax 67 with 55, 105, 165, and 300mm lenses
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tommyhawk13
sage
Reged: 09/28/07
Posts: 492
Loc: Jacksonville, Fl
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I have read that Kodak E100G was probably the best color transparency 4x5 film available.
Finding a fast lens would probably be the most important ingredient.
I have tried to compare films by reciprocity charts, but they don't take into account the real long exposure times.
Fuji Provia 100F looks good on paper, and so does Kodak E100VS, but how do they perform at about an hour?
--------------------
Meade Starfinder 8,Meade SN-8 OTA, Orion Atlas, and a handfull of film cameras
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Nightfly
super member
Reged: 06/20/07
Posts: 199
Loc: Sullivan, Maine
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Provia 100F is the best star trail film available. Great for long exposures at moderate apertures in that aplication.
For recording lots of detail in wide field piggyback work it is best with fast apertures, perhaps f/2.8 or faster. I've exposed it for over a half hour at f/4 and recorded only about as much as what E200 records in 10 minutes.
Jim
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Jim Cormier
Sullivan, Maine, USA
www.nightfly.zoomshare.com
Pentax 67 with 55, 105, 165, and 300mm lenses
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