Switch to English Language Passer en langue française Omschakelen naar Nederlandse Taal Wechseln Sie zu deutschen Sprache Passa alla lingua italiana
Members: 70,300   Posts: 1,536,057   Online: 972
      
Page 1 of 3 123 LastLast
Results 1 to 10 of 27
  1. #1

    Join Date
    Dec 2010
    Shooter
    Medium Format
    Posts
    19

    4x5 vs 8x10 DOF for street photography

    I'm still in the process of wrapping my head around the math of how the movements will affect DOF on a LF camera and I would normally wait to buy a system until I fully understood this but I have the opportunity to get a nice 8x10 at a good price but need to act relatively quick. Problem is I'm not sure if a 4x5 is a better choice. I will be using the camera mainly to shoot in the street with the end goal making really big (maybe around 5ft by 6ft) enlargements with very deep fields of focus. Subject movement will definitely be an issue so I'd say shooting at 1/400th f11 (or even f8) on 400 speed film might be typical.

    I know this is a highly subjective question and there are a lot of in-camera as well as in-scene factors that will change from shot to shot but I'm wondering if, in general, 8x10 with it's larger negative size will be able to yield sufficient DOF. Do any of you guys have experience shooting 8x10 or 4x5 in a situation like this or maybe just have some advice based on your best guesses?

    A typical scene might involve the camera at eye level with a person/car/etc 10-20ft away, a building facade 40ft back, and tall buildings in the background 200 or 300ft distant. If possible, I would like to have everything in focus or very near in focus.

    It seems to me that in general this type of situation would lend itself well to the wedge shape of the plane of focus created by lens movements. However, I'm not sure that the increase in apparent resolution yielded by the 8x10 negative will compensate for it's other disadvantages vs 4x5 in this area:

    1) more limited movements (intuitively this doesn't make sense to me but I've read this in multiple places. I understand that for the same field of view you have to use a longer lens but you are also placing the lens farther from the film plane so wouldn't the proportion of the image circle to the film area be equal in 4x5 and 8x10? )
    2) the requirement of opening the aperture up more to achieve sufficiently fast shutter speeds.

    I understand that for any given print size the 8x10 enlargement will have less DOF than the 4x5, but I'm wondering if you guys think the movements of an 8x10 system will be able to create the kind of DOF I'd like. Not having any experience with LF before, and not fully understanding the math yet, I'm not sure just how "magic" LF movements are regarding DOF.

    Also, portability will not be an issue since I am usually shooting within striking distance of my car.
    Last edited by gongman5000; 01-20-2011 at 08:17 AM. Click to view previous post history.

  2. #2

    Join Date
    Nov 2009
    Location
    Philadelphia
    Shooter
    Large Format
    Posts
    123
    It makes a difference whether we are talking about the same focal length lens or equivalent focal length lenses. First, because the depth of field for a 240mm lens is much less than for a 120mm lens even though they are roughly equivalent when the longer is used on an 8x10 camera and the shorter is used on a 4x5 camera. Secondly, the available movement for 4x5 lenses varies widely. Some (mostly designed for press cameras) are practically locked into straight ahead, while others are good for all of the available movements in your camera.

    Personally, I think it might be expecting WAY too much to be able to get a plane of focus involving three different vertical planes at varying distances, using f/11. At 10 ft, the depth of field is about 3 ft (150mm lens, assuming a circle of confusion of 0.1 mm. Which may be optimistic for prints that large). As distance increases, this value increases of course.

    The real issue is the "subject movement" requirement. If you could stop the lens down some, it would be useful.

    One more thing to consider: I don't think there are many 8x10 lenses with a shutter faster than 1/125th. Most modern lenses are in Copal 3.

  3. #3

    Join Date
    Dec 2010
    Shooter
    Medium Format
    Posts
    19
    That's good to know about the max shutter speed, I hadn't thought of that. I guess I could get away with 1/125th if I have to, and just be more discreet about my subject matter. That would solve some of the DOF issue anyway by letting me stop down a little more.

    when you say the DOF at 10ft. would be 3ft. you are talking about before lens movements right?

  4. #4

    Join Date
    Jun 2003
    Location
    local
    Shooter
    Multi Format
    Posts
    16,152
    Blog Entries
    1
    Images
    1
    hi there gongman ..
    i have shot street photographs with
    8x10, 5x7 and 4x5 cameras ...
    i think the problem you may run into with using an 8x10 aside from hoping to get 1/400thS at f8 ...
    is size ... setting up an 8x10 for streetwork, while it can be done it is impossible to be "stealthy" and
    it is kind of a pain in the neck. as for resolution &C ... if guillaume zuili's 35mm images ( some pinhole some traditional lens )
    can be enlarged to something like 30x40" i don't think you will have trouble enlarging a 4x5 sheet of film as big as you want.

    the other thing about 8x10 is that film is oodles more than 4x5 and film holders don't come too cheaply.
    all that said if you stop way down to f11 or 22 you might get the dof you are hoping for

    good luck !

    john
    silver magnets, trickle tanks sold
    artwork often times sold for charity
    PM me for details

  5. #5

    Join Date
    Nov 2009
    Location
    Philadelphia
    Shooter
    Large Format
    Posts
    123
    Quote Originally Posted by gongman5000 View Post
    when you say the DOF at 10ft. would be 3ft. you are talking about before lens movements right?
    Yep. That is the size of the focus wedge at 10 ft. Or something like that.

  6. #6
    Jim Jones's Avatar
    Join Date
    Jan 2006
    Location
    Rural NW Missouri
    Shooter
    4x5 Format
    Posts
    1,803
    You will have to use about two stops smaller aperture on the 8x10 to equal the DOF of the 4x5 for equal angles of view. For example, old Kodak DOF charts give 44' to infinity at f/11 with a 152mm Ektar and 56' to infinity at f/22 with the 12" Ektar. To simplify the math for working without DOF charts, for fairly critical sharpness the hyperfocal distance is about 2000 times the apparent diameter of the aperture as viewed from the front of the lens. A 5" lens at f/32 on a 4x5 camera might satisfy the OP's requirements while a 12" lens on the 8x10 should yield sharp images from 22' to infinity at f/45.

  7. #7
    ic-racer's Avatar
    Join Date
    Feb 2007
    Location
    Midwest USA
    Shooter
    Multi Format
    Posts
    6,184
    Quote Originally Posted by gongman5000 View Post
    I Not having any experience with LF before, and not fully understanding the math yet, I'm not sure just how "magic" LF movements are regarding DOF.
    The movements DECREASE depth of field. They change the location of the plane, but a tilted plane winds up with less depth front to back than the plane parallel to the film.

    In general, a constant linear aperture across film formats (when enlarged to the same viewing size print) leads to similar DOF. HOWEVER, the 'world' becomes more like a close up object the larger the film format, so that will decrease DOF more for the large format camera at closer distances. This really will come into play starting around 12 feet or so for an 8x10 camera.

  8. #8

    Join Date
    Jun 2003
    Location
    Portland, Oregon
    Posts
    1,317
    I'd suggest starting small and cheap. Buy a good 4x5 Crown Graphic press camera and put a 150mm studio view camera lens on it instead of a press camera lens. This will give you plenty of image circle for the limited movements such cameras offer. It's relatively light, fairly cheap, and easy to set up and focus. Buy some film holders and a few boxes of T-Max 400 sheet film with the savings over the 8x10 and have at it.

    8x10s are heavy, bulky, and slow to use. Setup and focusing are critical and take time and care. Wind and vibration become your mortal enemies. You will get more "keepers" for a lot less cash with a press camera. If you decide you need the bigger negative, trade up. My bet is that with 4x5 and a fine-grained high-speed film like T-Max 400, you will have everything you need, and you can carry enough film and gear for a day's shooting in a single manageable package.

    Peter Gomena

  9. #9
    Guillaume Zuili's Avatar
    Join Date
    Aug 2005
    Location
    Los Angeles & Paris
    Shooter
    Multi Format
    Posts
    2,639
    Images
    216
    It all depends on what you want to achieve with 2 options that will influence the way you shoot : handheld or tripod.
    Tripod you can use any format and camera but you loose the instant snapshot you may want.

    Handheld options are various.
    Box cameras with lens on hyperfocal. You are limited by the need of light to close down the aperture or you use flash (a strong one...)
    I used to shoot in Paris with a Hobo style 8x10 and had an assistant holding a Norman flash...
    Not really discret. A real pain in fact !

    The best option is the good old Graflex SLR. I got one recently and it's a joy to use handheld.

    Whatever you choose, you need to make it yours and make it work. Camera becomes your hand and you forget about it to concentrate on the subject,
    Easier in 4x5 than 8x10 for street photography. In the end you will have to compromise as for DOF, speed, etc...
    And for enlargement as John said there is no issue at all.


    G.

  10. #10

    Join Date
    Nov 2009
    Location
    Philadelphia
    Shooter
    Large Format
    Posts
    123
    No matter what you do, if you are using a LF camera for street work, the heisenberg uncertainty principle (and hence Schrodinger's cat) apply. You cannot take a picture without your subject knowing that you have a camera. Get used to that idea.

    By the way, I have taken to using a Crown Graphic with a Metz hammerhead flash as a night / bar camera. It is great, and very much in the press camera style. On the other hand, I don't use movements or anything, I just focus with the rangefinder.

Page 1 of 3 123 LastLast


 

APUG PARTNERS EQUALLY FUNDING OUR COMMUNITY:



Contact Us  |  Support Us!  |  Advertise  |  Site Terms  |  Archive  —   Search  |  Mobile Device Access  |  RSS  |  Facebook  |  Linkedin