long exposure photos with daylight

<p>Hi everybody,<br>

I have to take some long exposure photographs with daylight. the problem is that the exposure that I need would be around 30 minutes and eventually more than that. I am looking for a camera with which I can take long esposure photos (from 30 minutes to 1 hour) with day light. I've tried to make it with my Hasselblad by putting many filters, closing the aperture as much as possible and using a very low iso film but couln't make it.<br>

could anyone tell me if a pinhole could solve my problem? and if there is a film that can stand a long exposure like the one I need?<br>

thanks</p>

<p>Roberto</p>

<p> </p>

<p>I sure would love to know the point of this exercise, or what reason or circumstances you are dealing with. I think I just might learn something here.</p>

<p>If you are trying to do a time laps thing , you might just try multiple exposures on the same frame. Maybe use a camera with a lens that can go up to F90 or F128 as-well.<br>

You really need to let us know the application or type of photo you are trying to take in order for us to best help you.</p>

<p>An <a href="http://www.mrpinhole.com/calcpinh.php">"optimum" pinhole</a> for your Hasselblad (75mm focal length, 56x56mm film) would be about 0.298mm, which is ƒ/252.</p>

<p>At ƒ/252 @ ISO 100 in Sunny/16 conditions (EV 14 ⅔), your exposure time would be 2.4 seconds. You're still more than 10 stops away from an hour (not counting reciprocity failure).</p>

<p>So this is gonna be tough...</p>

<p><a href=" ask this guy</a></p>

<p>I specifically searched for "30 minute film exposure" on Google and he was the first link. He has a bunch of older long exposure shots as well. Very interesting.</p>

<p>I don't know exactly what you're looking to do, but you may try using a pinhole with photographic paper instead of film (slower). I personally haven't tried taking photographs this way, and you may not get the quality you're looking for with paper.</p>

<p>Would a pair of stacked 1000x or 9-stop neutral density filters do it?</p>

<p>I am with Derek on this one.</p>

<p>First, on most film cameras you can open the shutter for an indefinite period of time, as long as it has a "T" setting on the lens or a "B" setting and you can lock the cable release. Your manual Hasselblad should not be the limiting factor. (The only real exception to this are some electronic cameras which have a limit on how long the shutter will stay open.) So the camera itself is not the issue, it is the film and filters which must be the focus of your efforts. </p>

<p>Two factors to consider on the film are slow ISO and reciprocity failure. Basically, you want to have a film with very poor reciprocity characteristics. I would look at the reciprocity charts for different films and work backward from the chart to determine how many stops of filters you need. For example, assume you want a one hour exposure. If a film has a two stop adjustment for RF, you are down to needing a 15 minute base exposure (not adjusted for RF) for the film. Ortho film tends to be slow. Assume a ISO film of 25. Under the sunny f/16 rule, with no filter, you are up to 1/25 of a second at f/16, calculate the exposure with the smallest aperture on your lens. Say 1/8 at f/32. So you need to go from 1/8 of a second to 15 minutes. That is basically 13 stops.</p>

<p>So now figure out filters which will block 13 stops worth of light. A .9 ND filter is 3 stops, so you could put four of these plus a .3 filter on the lens to get your exposure. Or, you can go with a more dense filter. I have heard of photographers using welding goggle/face mask filters for long exposures. I don't know the filter factors for these, but they would be high. Try to google the filter factor for welding filters. </p>

<p>In high school I made a pinhole camera that took about half an hour for exposure. Made out of an old crackerbox. The secret: instead of film, I used paper, the same kind of paper that's intended for making enlargements in a B&W darkroom. Actually, my object wasn't to try to make a long exposure, it was to make the simplest camera I could. I had access to lots of photographic paper and the facilities to develop it (it can be easily tray developed under a safelight). The ability to work under a safelight also made it easy to load the camera. The long exposure was an unwanted side effect.</p>

<p>I made my prints by wet contact printing the paper negative face-to-face with another piece of paper. These days, scanning the paper and inverting on the computer is probably simpler for most folks.</p>

<p>hi guys thanks for answering on this.<br>

I've been trying several solutions but didn't succed yet. think I am gonna try with clouds and if that doen't work either I'll eventually try to do this at night. if anyone knows about best camera to use for long exposures with daylight please let me know.<br>

Roberto</p>

 

<p>The pinhole camera using 8x10 photo paper (about ISO 6) isn't a bad plan. Use a 0.76mm pinhole at 12.8" (equal to the diagonal), giving ƒ/428.</p>

<p>Now you're at about EV 10-11. Only four stops from Sunny/16 conditions, some of which will be taken up by reciprocity failure.</p>

<p>A 30 minute exposure of clouds will look like pretty much nothing, maybe flat grey, maybe grey-ish blue if the sky is coming through. There are many things to consider doing a project like this:</p>

<p>1. Do you have a tripod heavy and stable enough to hold the camera perfectly still for 30 minutes?</p>

<p>2. Are you shooting a subject that will be still enough to give you an image after 30 minutes? Moving clouds, passing cars, people walking, will probably all be completely invisible in a 30 minute exposure. </p>

<p>3. Are you wanting to shoot at day or night? They are two very different things and follow very different, almost opposite, rules.</p>

<p>4. Do you have access to light meter so you can get correct exposure? Just because it's a long exposure doesn't mean that guessing is going to work. At night it doesn't matter as much, but in daylight it does.</p>

<p>5. Have you studied reciprocal failure charts for the film you are using? All films have a different response to long exposures so even if you use a meter you will need to adjust the aperture to match the length of time you want based on reciprocal failure.</p>

<p>6. Are you bracketing your shots? Even with the meter and the reciprocal failure charts, bracketing is often the only way to ensure that you get the exposure you want.</p>

<p>To reduce the amount of light you could use crossed polarising filters, unfortunately it may be difficult to estimate the exposure. Do you want to use colour or B&W film ? The crossed polarisers are unlikely to be neutral in colour transmission, but then again the reciprocity characteristics of any colour film will give you something far from neutral anyhow.<br>

...Wayne</p>

<p> </p>

<p>1. Go to flicker.</p>

<p>2. Type "welding glass" into the search function. You will get 1533 results. </p>

<p>3. Look at the photos and read the comments on how these were taken. Look at the types of cameras used. </p>

<p>4. There is even a "<strong>Welding Mask Glass Filter</strong>" group.</p>

<p>5. If you don't want to try a welding glass filter, go to B&H and get one or two <strong>#110 ND filters</strong>. One filter will block 10 stops of light. </p>

<p>6. Do the math to get the correct exposure for your chosen film with the appropriate filter. Don't forget about reciprocity adjustments.</p>

<p>Do all of the above, but search for "ND 110 filter".</p>

<p>An infrared filter (R72) transmits an extremely small portion of visible light. Here's one I did using an R72 with Panatomic-X (ISO 32) for about 5 minutes. The aperture was f8.</p><div></div>

<p>I would recommend a manual camera that does not depend on batteries to operate the shutter. A long time exposure is a heavy drain on a battery. The picture I posted was done with a Minolta SRT 201. If the manual camera has an LED display in the finder you should remove the batteries as the light from the display may find its way to the film. That happens with my Yashica FX-3 Super 2000.</p>

<p>Hi Roberto. I've done this before and I found it useful to use a film like Ilford XP2. This has a wide exposure latitude and makes it easier to get good exposures. Some of the above posts make this sound very difficult. It isn't. You will need to do a few trials to get the exposure right, but after that it is easy. Your choice of camera isn't very critical, with one proviso: electronic shutters use up batteries very quickly when using time exposures, so mechanical ones are better.</p>

<p>As for filters, B+W make 6 stop ND filters (<a href="http://www.speedgraphic.co.uk/prod.asp?i=16083&1=B%2BW+ND1%2E8+%286+stops%29+106">http://www.speedgraphic.co.uk/prod.asp?i=16083&1=B%2BW+ND1%2E8+%286+stops%29+106</a>) and 10 stop ones (<a href="http://www.speedgraphic.co.uk/prod.asp?i=16388&1=B%2BW+ND3%2E0+%2810+stops%29+110">http://www.speedgraphic.co.uk/prod.asp?i=16388&1=B%2BW+ND3%2E0+%2810+stops%29+110</a>). They are not cheap and an alternative approach might be to stack 4 stop filters from this company (<a href="http://www.srb-griturn.com/srb-neutral-density-filters-527-p.asp">http://www.srb-griturn.com/srb-neutral-density-filters-527-p.asp</a>)</p>

<p>The great thing about very long exposures is that exposure time becomes much less critical. If you are exposing for several minutes, a few second either way is not critical.</p>

<p>Have fun.</p>

<p>Alan</p>

<p>Two ladies from Belgium did a series of day light pin-hole pictures with exposures lasting for hours (even up to 24 hours, if I remember well). They used a camping trailer with a huge piece of photo paper inside.<br>

Look for "Caravana Obscura".<br>

One of their most impressive picture is taken at a swimming pool in Luxemburg during a busy summer afternoon. The hundreds of people playing in and around the pool are completely invisible, due to the very long exposure. However, there's a small darker blurry area at the top of the diving board, where people stood in line to dive, staying stiller a bit longer.<br>

<a href="http://www.thefreelibrary.com/Felten-Massinger:+Galerie+Michele+Chomette.-a0143569320">http://www.thefreelibrary.com/Felten-Massinger:+Galerie+Michele+Chomette.-a0143569320</a><br>

<a href="http://lunettesrouges.blog.lemonde.fr/2009/12/09/caravana-obscura/">http://lunettesrouges.blog.lemonde.fr/2009/12/09/caravana-obscura/</a></p>

<p>http://www.pinholephotography.org/SSGB%20Page.htm</p>

<p>These exposures are 6 months long. </p>

<p> </p>

<p>Hi Roberto:<br />Here is my suggestion:<br />The longer the lens focal length, the better you will be able to achieve a higher f value. (The f stop being related to the focal length, it is easier to use a pinhole on a large format, making it possible for you to get by without a machine shop or such.) I suggest a 19 or 23 inch focal length. This might be an old wall camera lens from a graphics shop or newspaper cold type operation, Chemco, levy or Nikon lens that stop down to f256 or I have seen old Degor f512 fl 26in They are not real common but not too high in price because pages aren't done on cameras that much any more. A NY or Chicago Graphics Supply Wholesaler might help. I used to buy such lens for about $200.00 in the 70s. You might look for an old aerial camera at the army surplus store, some had focal length of 20 in also. Then comes the fun, rigging such a lens with a large format camera, 8x10 seems the best bet. Afte Thought, Film choice is likely continious tone graphic arts copy film, Agfa or Illford, either Ortho or Pan, ortjo being less prone to recip issues and designed for 30 sec or longer exposure, ASA 3 or so.<br />I used to work for a paper in Englewood NJ " The Press Journal" They had an old Levy, vintage 1923 that I am sure, knowing the publisher never sold anything, is still out there.<br />Good luck and keep shooting.<br />Leon</p>

<p>Hi everybody,<br>

does anybody know where I can buy ND filters? the problem is that I need the strongest and most dense neutral filters EVER. need them to do these very long exposure we talked about above. I tried to go to several shops but they have filters that are too light, like 4 stops or so.<br>

do you think there are 10 stop (or more) ND filters that I can buy?</p>

<p>There are a lot of people interested in long exposures, and doing so with ND filters, not pinholes. For example, see:</p>

<p>http://www.redbubble.com/people/peterh111/journal/4421304-the-ultimate-easy-guide-to-neutral-density-filters<br /><br />http://www.alexwisephotography.net/blog/2010/02/16/guide-to-daytime-long-exposures/<br /><br />http://forums.overclockers.co.uk/showthread.php?p=15199037<br /><br />http://www.talkphotography.co.uk/forums/showthread.php?t=151141<br /><br />http://www.flickr.com/groups/longexposure/discuss/</p>

<p>HTH,</p>

<p>Tom M.</p>

<p>Roberto,<br>

Is this the photographs you were referring to in google?<br>

<a href="http://www.ajrosenbergmedia.com/Portfolio/Portfolio-One/9146418_UCbHX/2/610040949_2D44q#610040949_2D44q">http://www.ajrosenbergmedia.com/Portfolio/Portfolio-One/9146418_UCbHX/2/610040949_2D44q#610040949_2D44q</a><br>

Looks more to me like a shot a night in near total darkness.</p>