Page 2 of 3 FirstFirst 123 LastLast
Results 11 to 20 of 23

Thread: Exposing at non-box ISOs: Why?

  1. #11

    Join Date
    May 2007
    Location
    Greenwood Lake NY USA
    Posts
    148

    Re: Exposing at non-box ISOs: Why?

    To the OP:
    In case these extensive replies seem overwhelming here is a simpler answer, deviation from the box conditions is an adjustment of film contrast and also partly to ensure shadow detail is recorded. This is optional and may not be needed in many situations. Also image contrast can be adjusted when making the print.

    The box speed and standard development will take you a long way in the photographic journey of landscape photography, it is safe to start there.

    PS the Ilford data sheet for FP4 includes details for processing at different speeds and in a variety of developers. This kind of hard information provided by the manufacturer is always my first point of reference.

    https://www.ilfordphoto.com/amfile/f...roduct_id/690/
    Last edited by Ted R; 4-Jun-2017 at 12:36.

  2. #12
    Vaughn's Avatar
    Join Date
    Jan 2007
    Location
    Humboldt County, CA
    Posts
    6,387

    Re: Exposing at non-box ISOs: Why?

    Have a great trip this summer! I learned to photograph under the redwoods. Back then (late 70s) I cut the box speed (4x5 Royal Pan) in half because I was getting better negatives. Actually, what was happening was that all my exposures were long...up to 30 minutes or so is common during the middle of an over-cast day in the redwoods. I was slamming against resiprosity failure without a clue what it was. But I just kept going back into the redwoods, adding exposure and fooling with development until I got negs that could get me the prints that I wanted. Now I rate film at box speed and correct for resiprosity failure after metering...it is actually a nice contrast-tool.
    "Landscapes exist in the material world yet soar in the realms of the spirit..." Tsung Ping, 5th Century China

  3. #13

    Join Date
    Jul 2016
    Posts
    1,211

    Re: Exposing at non-box ISOs: Why?

    Quote Originally Posted by Paul Kinzer View Post
    I'm doing my best to get started...

    I've only read the Domremus answer. It explains it perfectly.

    I only want to add something. LF shutters are mechanical, and not as precise as electronic ones. Even brand new shutters may vary +/-30% from their marked speed. Old shutters... well...

    I've you have not checked your shutters with a shutter tester better you overexpose a bit negative film, as a safety belt. (slides is the counter)

    Let me make a recommendation I used when I started. Have a 35mm roll of the same film than sheets. Shot the sheet, but also make a 3 shot bracketing with a SLR (Nikon F80 or the like) with same exposure and +/- 1 stop. Consider bellows extension correction...

    Then, after developing, you can compare. A LF lens and a SLR 50mm may have a very similar transmitance, so any difference may be because shutter or another factor.

    For each shot you will know how an alternative exposure would have worked, helping future decissions.

    Regards

  4. #14

    Join Date
    Mar 2017
    Posts
    178

    Re: Exposing at non-box ISOs: Why?

    Wow! Thanks for all the very clear and helpful responses. Some of the comments confirmed what I had already gleaned from my own reading, and also cleared up much of the 'noise'. Just a week or two ago, much of what's been written here would have been beyond my knowledge base, but I've been reading like someone possessed by a photo demon, so I think I timed my post correctly.

    I'm especially grateful for two things here, both thoughtfully and simply expressed: pragmatic 'here's what you do' pointers; and the 'here's why you do it' responses. I learn skills much better when I have both of these kinds of knowledge to work from.

    I've bookmarked this thread and placed it high on my list as a place to come over the learning curve I'll be starting on once I have film in my holders and chemicals in my bathroom! I think this is one of the best threads I've read so far about this topic, and I think it will help others who are just starting out, too. I agree completely with what Sweep said in comment number 4: 'I am starting to get impressed by the amount of time that some established members invest in answering question such as this.' But I am past 'starting'! Thanks very much. You are all more than just words on a screen, and I am grateful for the time and effort given to us newbies.

    I'm not going to take the time to respond to individual posts, at least not yet. For one thing, they are so clear that I don't feel the need. But I will say to Pere Casals, above, that his advice is well-made. I do own an electronic shutter tester. I repair Speed Graphic cameras, and adjust their focal plane shutters, so I needed a tester for that*. I use it, too, to test the shutters on the many lenses I get with these cameras. None are spot on, especially at the higher speeds. More important, I think, is that the higher speeds tend to be much less consistent in their speeds. On the other hand, some of these old mechanical things work surprisingly well, and though almost all have some speeds that are either way off or not consistent, most have several speeds that are just fine. As long as those are the speeds that are used, everything should be fine.

    For example, in front of me I have a 152mm Kodak Ektar in a Graphic Supermatic shutter. The 1 and 2 settings are spot on and very consistent. 5 fires at 4 (which is actually a good thing); 10 fires at 8 (again, good); 25 fires at 22 (close enough); 50 fires at 40 (good to know); 100 fires at 60; and 200 at 125 (both nice for modern uses).

    I'm surprised at myself as I get more into getting ready to actually use these things as they were meant to be. I've had probably a hundred or more LF cameras pass through my hands, and even more lenses, but I've only used them occasionally, and then mostly with MF backs on them. I know quite a bit about the gear, but not about its use.

    Paul

    * I don't get them to full speed, and don't want to try anymore, since I tore two shutters in a matter of months. But how often do you need a 1000 shutter speed in LF, anyway? I get them up to about 700-750/350-375 for the highest setting, which makes the middle ones close to right on, and the lowest a bit fast. And my project for today is to test four lens shutters for a Speed I'm but to sell, and then the five shutters on the lenses I've gathered for my own use. I'll make little labels on sticky-back address labels, and stick them on the lens boards. I'll check them again after a time to see if they change. It's an easy thing to do, and important, too.

  5. #15

    Join Date
    Apr 2006
    Location
    San Antonio, TX
    Posts
    60

    Re: Exposing at non-box ISOs: Why?

    Paul,

    I would second getting Ansel Adam's "The Negative".

    It's a great place to start.

  6. #16

    Join Date
    Mar 2017
    Posts
    178

    Re: Exposing at non-box ISOs: Why?

    Hey, one more book! I've bought and read about fifteen-twenty so far, and have thought about the Ansel Adams books. I think someone I know has them, but I like having them nearby. My wife, the public librarian, can get most books for me, but some of the photography books that have been recommended have been unavailable in libraries. Adams' books should be there to check out, though.

    Thanks!

  7. #17

    Join Date
    Sep 2012
    Location
    Mt. Pleasant, Wisconsin USA
    Posts
    98

    Re: Exposing at non-box ISOs: Why?

    +1 re the discussion offered by Doremus!
    ... JMOwens (Mt. Pleasant, Wisc. USA)

    "If people only knew how hard I work to gain my mastery, it wouldn't seem so wonderful at all." ...Michelangelo

  8. #18
    8x10, 5x7, 4x5, et al Leigh's Avatar
    Join Date
    Dec 2010
    Location
    Maryland, USA
    Posts
    5,028

    Re: Exposing at non-box ISOs: Why?

    The only reason to over-expose (using a lower-than-box ISO) is to increase shadow detail.

    Mid-tone and highlight rendering are controlled by development. Shadow detail is not.
    You need only examine the development-time graphs for any film to confirm this.

    Here's an example graph showing different development times.
    Shadows are to the left, highlights to the right. Density increases vertically.
    Each line is a different development time.
    Note how they're all the same at the left end, in the shadow densities.



    - Leigh
    Last edited by Leigh; 5-Jun-2017 at 04:32.
    If you believe you can, or you believe you can't... you're right.

  9. #19

    Join Date
    Sep 2014
    Location
    North Dakota
    Posts
    514

    Re: Exposing at non-box ISOs: Why?

    You might look at the books on B&W PHOTOGRAPHY and BEYOND BASIC PHOTOGRAPHY by Henry Horenstein.
    I tend to procrastinate on stuff. One of these days I'll do something about it.

  10. #20

    Join Date
    Dec 2005
    Location
    Los Angeles, CA
    Posts
    4,426

    Re: Exposing at non-box ISOs: Why?

    Quote Originally Posted by Ted R View Post
    To the OP:
    In case these extensive replies seem overwhelming here is a simpler answer, deviation from the box conditions is an adjustment of film contrast and also partly to ensure shadow detail is recorded. This is optional and may not be needed in many situations. Also image contrast can be adjusted when making the print.

    The box speed and standard development will take you a long way in the photographic journey of landscape photography, it is safe to start there.

    PS the Ilford data sheet for FP4 includes details for processing at different speeds and in a variety of developers. This kind of hard information provided by the manufacturer is always my first point of reference.

    https://www.ilfordphoto.com/amfile/f...roduct_id/690/
    +1

    Understanding the theory and practices is critical to success but don't get crippled by either the details or the process fine tuning unless there is a good reason to do so.

Similar Threads

  1. Exposing Portra
    By gevalia in forum Darkroom: Film, Processing & Printing
    Replies: 2
    Last Post: 3-Oct-2009, 15:47
  2. Exposing Tri-X
    By Salvatore Formisano in forum Darkroom: Film, Processing & Printing
    Replies: 11
    Last Post: 1-Jun-2009, 00:46
  3. Exposing with a bright sky
    By blevblev in forum Style & Technique
    Replies: 11
    Last Post: 5-Mar-2008, 22:23
  4. exposing Polaroid 665
    By Dave Aharonian in forum Darkroom: Film, Processing & Printing
    Replies: 1
    Last Post: 7-Aug-2006, 18:27
  5. Exposing AZO
    By joe freeman in forum Darkroom: Film, Processing & Printing
    Replies: 8
    Last Post: 27-Apr-2002, 00:35

Bookmarks

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •