Good looking Cardinal at 1000mm (1500mm equiv)

Discussion in 'Digital SLR' started by M-M, May 21, 2007.

  1. M-M

    M-M Guest

    Taken with Nikon Fieldscope 82/D80. Uncropped, but reduced to 25% of
    original size for posting. I applied usm to the bird only with amount=
    100%, radius= 1 pixel (after reducing the size) and that is the only
    M-M, May 21, 2007
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  2. M-M

    DM Guest

    Thanks, great photos! I am considering the purchase of a Fieldscope and
    DSLR adapter for some time in the future. Any hints or advice?

    DM, May 21, 2007
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  3. M-M

    Matt Clara Guest

    In essence then, you sharpened every pixel in the picture...
    Nice, if not exactly tack sharp.
    Matt Clara, May 21, 2007
  4. M-M

    M-M Guest

    In essence then, you sharpened every pixel in the picture...[/QUOTE]

    I selected just the bird and sharpened the selected area. I wish I
    understood this USM better. Sometimes I use Radius=30, Amount=20%.
    M-M, May 21, 2007
  5. I selected just the bird and sharpened the selected area. I wish I
    understood this USM better. Sometimes I use Radius=30, Amount=20%.
    There are tutorials available for free download that can help. One or
    two such are produced by Jan Kabili.

    I am now using smart sharpen in CS3 instead of USM, but who knows? It's
    smarter than I am, that's certain!
    John McWilliams, May 21, 2007
  6. M-M

    M-M Guest

    I guess we're getting a bit off-topic, but what exactly do radius and
    amount refer to?
    M-M, May 21, 2007
  7. No - the USM radius setting should not be taken so literally.

    For instance try it out with a radius = 0.3 and amount = 170.
    This will often give very crisp edges with little haloing.
    Gisle Hannemyr, May 21, 2007
  8. Amount is the "strength" of the effect - the higher number you use for
    amount, the higher the increase in contrast will be.

    Radius is a measure of the area to take into account when detecting
    edges to apply the effct to. A small number (e.g. 0.3) localize the
    effect and create crisp edges, a large number (e.g. 30) spread the
    effect over a larger area. A large enough radius will boost general
    contrast without really affecting the edges.

    The "radius" and "amount" are just numbers that go into a fairly
    complex computation. They should not be interpreted literally to
    refer to pixels or percentages.
    Gisle Hannemyr, May 21, 2007
  9. M-M

    M-M Guest

    Doesn't it depend on the resizing? Wouldn't a 10MP image reduced to 25%
    for posting on the web require different USM settings than that same
    image at full resolution?
    M-M, May 21, 2007
    Gisle Hannemyr, May 21, 2007
  11. M-M

    Paul Furman Guest

    BTW I try to use radius 0.5 to 0.8 if it's a tack sharp image... if it's
    real soft those radii only sharpen the noise and I experiment... it
    might need a radius of 2 and I generally have the Amount at more like
    150 or 200.
    Paul Furman, May 21, 2007
  12. M-M

    RichA Guest

    Digiscoping. 2 images, downsized 4x each.

    300mm lens. (600mm equivalent)

    2876mm digiscope image (5752mm equivalent, 380mm f5.9 apo telescope
    and stacked teleconverters).

    If you were to look at both images, the 300mm image is rudamentally
    sharper, but it does not have the same resolution as the digiscope's
    far greater image magnification allows. This is the difference
    between sharpness and resolution.
    Digiscoping is an extreme (or can be) solution if you don't have 1000mm
    + focal length and you need it.

    Another benefit of digiscoping is the flexibility to choose focal
    lengths based on eyepiece choices for the telescope.
    While not capable of true "prime focus" (front lens as the only
    optical element) because of the added eyepiece, it can offer focal
    ranges from anywhere from 700mm or so to over 5000mm, with an
    attendant loss of photographic speed, of course.
    RichA, May 21, 2007
  13. M-M

    M-M Guest

    Here's another example:

    First photo at 180mm with a regular telephoto, next 3 images digiscoped
    at 1500mm, 3000mm and then 9000mm
    M-M, May 21, 2007
  14. M-M

    RichA Guest

    RichA, May 21, 2007
  15. I think I'd quickly add that I am pretty sure you generally work on full
    sized images. e.g., what settings work perfectly for a 4000 x 3000 px
    image rather suck for a 600 x400 image.
    John McWilliams, May 21, 2007
  16. M-M

    Paul Furman Guest

    Yes those numbers are for pixels straight out of a digital camera. I got
    a copy of a photoshop action for resizing to web that does the
    downsizing in a few steps... here's what it uses:

    resize to 1280x1280
    amount: 120%
    radius: .3

    resize to 640x640
    amount: 70%
    radius: .3
    ....output web image

    resize to 100x100
    amount: 70%
    radius: .3

    resize to 1280x1280
    amount: 70%
    radius: .3
    ....output thumbnail

    Maybe I should have gone down to below 70% for the thumbnail resizing
    when I added that part, maybe the radius could be varied for better
    results? It depends on the image, and the print size & there's probably
    more than one way to do it with good results.
    Paul Furman, May 22, 2007
  17. I am sure of that, although unsure of where to turn for the definitive

    I recall you live in the Bay Area, and wonder if you've uncovered any
    continuing ed. courses in PS? I took the introductory course at Berkeley
    City College (then Vista). I have taken a bunch of other classes there,
    but none are really PS classes at the advanced level.
    John McWilliams, May 22, 2007
  18. M-M

    ASAAR Guest

    One of the scraps that B&H includes in the bags with your
    purchases is occasionally a notice of several advanced PS courses
    taught by a band of roving PS experts. They'll probably eventually
    reach (or return to) your area. I don't know if this is something
    that B&H also sends via email if you ask to be notified of offers,
    but it might be worth checking. You could also be worthwhile
    checking Adobe's website for classes. I just checked, and they have
    a link for Training and Certification on their home page.

    Another possibility. When you're next in a good bookstore, check
    some of the PS books, as a number of the authors are likely to be
    affiliated with others that teach PS courses, and should provide
    contact details & URLs.
    ASAAR, May 22, 2007
  19. Thanks. The Adobe and affiliated parties (or Adobe 'approved") are well
    represented and advertised here, but I have had my fill of these, with
    the exception of a Lightroom presentation which hasn't be done in the
    Bay Area. L.A. and Boston, tho, have had it.
    John McWilliams, May 22, 2007
  20. M-M

    Ryadiia Guest

    I selected just the bird and sharpened the selected area. I wish I
    understood this USM better. Sometimes I use Radius=30, Amount=20%.

    You might consider an "action" to sharpen your images. This creates a
    sharpening layer which you can play around with in real time and see it's
    effect. Also you might consider using a different approach to USM sharpening

    300% at 0.2 radius is a good starting point.

    High Pass Sharpening is definitely the best method of sharpening an image I
    have used.
    All the images here: have been
    sharpened with a high pass action.

    Ryadiia, May 22, 2007
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