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close up shots with no/little DOF

Discussion in 'Photography & Video' started by proffesso, Sep 8, 2014.

  1. proffesso

    proffesso Member

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    hey guys, im doing a fair bit of 3d photogrammetry right now, and need to get in close to some objects. right now I have a 50mm 1.4 lens that is OK, but wont let me get in close enough. so im thinking I might need a macro lens.

    can these macro lens's get close in without crazy shallow dof? I need to minimize DOF as much as possible. (all shots i see are mega-blur backgrounds)

    objects I need to take shots of are around 10 - 20cm in size, but need a lot of photos very close up.

    camera is a nikon d7000
     
  2. Taverner

    Taverner New Member

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    You can shoot with a narrow aperture for a larger DOF, which will require more light for a faster shutter speed (not necessarily an issue if the subject isn't moving and you're on a tripod) and you can stack images at different focal points to get the whole thing in focus.

    Can I ask why you need to get so close for something that big (20cm)?
     
  3. dodgyexposure

    dodgyexposure Member

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    The closer you get to 1:1, the narrower the DOF will be, even at narrow apertures (f16, f22).

    If you want macro shots with deep depth of field, you need to be focus stacking.
     
  4. OP
    OP
    proffesso

    proffesso Member

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    bascially that 20cm object will get blown up 20x and I need all the surface detail I can get. I will be taking 30 - 40 shots of each object with only a handful being cropped to the object itself, most will be in much closer. im making a resulting texture of the surface detail to roughly 8192x8192, so detail needs to be pin-sharp.

    cant really do focus stacking since I cant use a tripod (360 degree shots of the object...and the object I cant move/touch)

    quite an interesting subject, considering its against all the usual rules of photography :)
     
  5. Taverner

    Taverner New Member

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    It's certainly an interesting challenge - I suppose you'd want to use the sharpest possible lens you can get your hands on. It doesn't sound like close focusing will be an issue since you're not really trying to do 1:1 pictures (unless you're planning to take a bunch of closeup pictures and stitch together?
     
  6. methd

    methd Member

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    really small aperture and maybe get your hands on a TS lens to get the DOF running away from you.
     
  7. lionman

    lionman Member

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    This would be the easiest solution. Tilt shift lens will let you alter (tilt) the angle of the DOF to run along the surface of the object.

    I cant see why focus stacking is out of the equation though. Cant you position tripod, take a series of images at different focal distance for stacking, then move the tripod slightly around the object and repeat? Keep doing this until you have the data you need?

    Not really familiar with what your doing though.
     
  8. OP
    OP
    proffesso

    proffesso Member

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    Click to view full size!



    since they are tree trunks, I cant get a tripod up and around a branch (im only doing a branch, not the entire tree) but I still need a good 30 - 40 pics, close up and establishing/object crop shots. current detail is just not there with the 50, so need to get in closer. but im also throwing away a lot of information with the dof.

    Tavaner- after the object scan is done, the texture is basically all of them stitched together. the final res needs to be enough that I can zoom into a section and still be 1:1 pixel ratio on a monitor....ideally. right now the 50 gives me roughly a 2k res total...quite a bit off.
     
  9. Taverner

    Taverner New Member

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    So I gather the branch is still attached to the tree (and people would be upset if it became detached)?

    If that's the case and you can somehow get close enough to photograph all sides, your best bet might be a ~60mm macro lens with a ring light to help get the subject bright enough for ~f/11 at a shutter speed that will let you hand hold, and then just lots of photos/stitching. I'm only speculating here, since I've never needed to do anything remotely similar - if you're lucky someone here will have some prior experience :D
     
  10. Statitica

    Statitica Member

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    Sounds to me like you are going to need to try a focus stack panorama. Doesn't look to be the easiest thing you could do...

    A macro set up will get you more detail, but increase your work load by making you take more photos for both depth of field, and amount of subject per frame. Tilt-shift would definitely help.
     
    Last edited: Sep 8, 2014
  11. OP
    OP
    proffesso

    proffesso Member

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    if I could cut them off, I would be set...but alas, parks and recreation officers dont like that :/

    I might be able to rent a camera as well, like a D810 with more res/better light performance.
     
  12. Dark Orange

    Dark Orange Member

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    Have you thought of going longer (300mm+) and standing back a little? Maybe use an extension tube to get a little closer.
     
  13. OP
    OP
    proffesso

    proffesso Member

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    very difficult with all the other trees in the way, and since I need complete 360's, its no small task alas
     
  14. lionman

    lionman Member

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    what about just using extension tubes on your 50mm to decrease the minimum focus distance?

    If you shoot stopped down the DOF should be ok, you may have to take quite a few more photos though.
     
  15. Jackolow

    Jackolow Member

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    If you're using Canon, I'm pretty sure there is a focus stacking feature on magic lantern. I think you can set the intervals it stacks as well.

    So if it's all stationary, i think it's one press then it takes all the photos you want. Then you focus stack in your program of choice
     
  16. Dark Orange

    Dark Orange Member

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    Buy macro lens, use ring flash, close aperture right down.
     
  17. sold

    sold Member

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    Consider a decent quality compact if the image quality will suffice. e.g. Canon S110

    Small sensor = shorter focal length = big DoF
     
  18. sejanus

    sejanus Member

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    Your other problem is that at very small apertures the lens will be well and truly out of it's comfort zone and will be starting to get soft. Especially at f/22 or thereabouts.

    I don't know the answer. If I was going to try it I'd probably stop thinking of getting as close as you can. Get a bit further away with a mid length lens (say 100mm'ish) and then crop later on to "zoom in".
     
  19. lionman

    lionman Member

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    Good solution.

    Just shoot with your phone if its decent. How much detail do you really need?
     
  20. OP
    OP
    proffesso

    proffesso Member

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    a LOT of detail. jpg fine doesnt cut the mustard on full crops on my D7000.

    im taking a small area, blowing it up hugely for on-screen use.

    jpg aretefacting loses a lot of fine details in 3d scans (ive tried the phone approch) and gets nowhere with texture resolution

    a 16mp shot fully cropped to the object has almost enough detail (shot in raw)

    i will consider a point and shoot, if I can macro style zooms out of it, im blowing up a small area to almost 12mp. so has to be sharp as possible
     

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