Slow films, long exposure: to push or not to push?

[tony_demma]

<p>Hey everyone, I'm planning a trip to California where there will be good opportunities for long exposure night photography. I was considering Delta 3200, but I did a little more research and found that it would not be the best film for the job, and instead I should use a slow film such as Acros 100. My question is: should I shoot it as 100 ISO, or push it to 3200? I'm aiming for shots of the milky way without star streaks.</p>

[larrydressler]

<p>Don't push it. Shoot at Box speed develop it normal Look up Schwarzschild effect. Acros 100 is one of the better films for this type of photography.</p>

[kivivuori]

<p>Acros 100 is definitely THE best choice<strong> if you want</strong> to use medium/slow film. Its extremely sharp, fine tonality and it`s not troubled by reciprocity failure. But you just can`t push it up to ISO 3200!<br /><br />See more: http://www.fujifilmusa.com/shared/bin/NeopanAcros100.pdf<br /><br />If you use MF or LF you could also use Kodak Tri-X or Ilford HP5+ films. They both work very well at ISO 1600. I´ve pushed Ilford HP5 up to ASA 12800.<br /><br />BR<br /><br />Esa Kivivuori<br />Finland<br /><br /><br />Photo: Thunderbird HP5 12800 ASA © Esa Kivivuori.jpg<br />(Canon F1, FD 24mm /2.8 SSC, hand held)</p>

<p> </p><div></div>

[tony_demma]

<p>Thanks guys!</p>

[dhbebb]

<p>Due to the process of image formation, any black-and-white negative film becomes effectively more contrasty with very long exposures (to put it extremely simply, the highlights are able to build and go on building, the shadows have trouble getting started). It takes increased exposure and reduced development tame this contrast. Push processing, or in other words going the other way, is very likely to result in extreme and unprintable contrast.</p>

[jamie_robertson2]

<blockquote>

<p>I'm aiming for shots of the milky way without star streaks.</p>

 

</blockquote>

<p>Then you've got next to no chance using Acros unless you have a motorised equatorial mount for your camera. For example, if you're shooting with a 28mm lens you'll be limited to an exposure time of around 18 seconds before the stars start to streak. 18 seconds at ISO 100 is nowhere near long enough to get milky way shots even with a very fast lens. </p>

<p>If it were me I would use something like HP5 and push it to ISO 1600. Even then you're going to need a fast lens to get a half decent milky way shot. Shots like the type you are after are better done with digital cameras in my opinion.</p>

<p>For static subjects such as the excellent Thunderbird photo by Esa, Acros is the film to use. Shoot it at ISO 100 and develop normally. </p>

[Fotohuis RoVo]

<p>Increasing speed before exposure: <strong>Hypersensitation.</strong><br>

<strong> </strong><br>

<strong><br /></strong>It is called gas-hypering or hypering. This technique was used with Kodak 2415 Tech Pan. Before exposure the film is soaked in a forming gas mixture of 92% Nitrogen and 8% Hydrogen for several hours. The effect can last for years if the film is properly stored.<br>

This techniques was especially used for astronomers. Instead of several hours in exposure the film is exposed in about some minutes.<br>

It is also not working well with modern films.</p>

<p>This technique was first published by Everhart in 1981.</p>

 

[tony_demma]

<p>Thanks for the tip, James. For the Milky Way, I guess I'll have to use Delta 3200 and cross my fingers (with a digital camera nearby). Acros will be reserved for star streaks if not static shots.</p>

<p>Robert, thanks for the information. Although that's wayyyy out of reach for me, it's pretty cool.</p>

[todd_niccole]

<p>I have experience in film astrophotography and made many film tests over the years with reciprocity in mind. The fastest films are generally the worst like Ilford 3200 and the defunct Kodak 3200. Aside from that the all time worst films for any astrophotography are Rollei. If your going to do fixed tripod shots then something like Tri-X, Tmax400 or Ilford HP5 at 30 seconds pushed processed would be best with a 50mm lens wide open. These films would actually be faster for images under a couple of minutes than Acros or even hypered Techpan.</p>

[jamie_robertson2]

<blockquote>

<p>For the Milky Way, I guess I'll have to use Delta 3200 and cross my fingers</p>

 

</blockquote>

<p>You will probably find that there will be so much grain that you will have difficulty establishing which is grain and which are stars. I've tried it before and the results are very disappointing. Slow film looks great for static shots at night but digital is a gazillion times better for astrophotography.</p>

[glen_h]

<p>Some years ago, I took some pictures by the light of a full moon. </p>

<p>No worry about star streaks, so I could do long exposure, if I remember<br>

about 45 minutes for Ektachrome 64, somewhat less for Ektachrome 200.</p>

<p> </p>

[denny_rane]

<p><br />Esa Kivivuori<br />Finland<br /><br /><br />Photo: Thunderbird HP5 12800 ASA © Esa Kivivuori.jpg<br />(Canon F1, FD 24mm /2.8 SSC, hand held)</p>

 

<blockquote>

<p><img src="http://static.photo.net/attachments/bboard/00d/00dRpa-558096784.jpg" alt="" width="600" height="398" hspace="5" vspace="10" data-original="http://static.photo.net/attachments/bboard/00d/00dRpa-558096784.jpg" /></p>

<p>Wow...THAT is hand-held eh.?<br>

Is there a Book, Link, Tutorial, Forum... that deals with the specifics of shooting (and developing) B&W Film at night.?<br>

Thank You</p>

</blockquote>