DP1m with the Ricoh GW3 WA converter

Discussion in 'Sigma DP Forum' started by pinholecam, Nov 9, 2013.

  1. pinholecam

    pinholecam SC Regular

    Aug 3, 2012
    Finally got a chance to do this and hope the results will be useful to everyone.

    Managed to borrow a Ricoh GW3 wide angle converter for the GR to test our on the DP1m.
    This is a converter than converts the 28mm to 21mm eq for the Ricoh GR and by most reports, a very good WA converter.
    Ironically, the GW3 is 49mm thread and the GR needs an adapter for it.
    On the Dp1m, it just screws on.

    So here are the results.

    W/o WA converter

    with WA converter

    Pls go to the original full sized samples to have a detailed look.
    I'm pretty lazy and dislike doing 100% cut outs and making sure they are rightly sized on flicker to prevent excessive compression and all that. :D

    Personally, I'm at a dilemma because of what it gives and what it takes away.
    1. Much wider with the GW3 .

    2. IQ in the center and for the most part the 75% of the frame, is not degraded that badly and can be recovered with a bit stronger sharpening (low sharpening settings by bayer filter standards actually). The usual DP1m shot needs none to a 25% str, 0.1 radius for my taste. With the GW3, perhaps it needs 50%; 0.2-0.4

    3. There is vignetting on the corners. Not a big problem if there is nothing on the bottom corners (eg. roads/ trees/bush). Easily touched up if its sky.

    4. Edges are actually ok. Only the corners are bad

    5. Corner IQ drops off rapidly. Again, may be ok if the part of the photo at the corners are 'mushy' stuff like the sea, water, beach sand, bushes/grass (maybe). Can be a real disaster if its buildings like in this case.
    It can be rectified a bit with careful cloning work for some photos, but hard to count on it.
    I'd think that the composition of a photo using the GW3 on the DP1m will have to take into account the poor corners,
    Either leaving important stuff out of them, or composing with the idea of cropping out the corners.

    So mixed feelings.
    It opens up possibilities with the wider angle on a small kit.
    But corner IQ is bad.
    Its about $300, and imo, for the pros/cons, it would be an easier decision to buy if it was nearer $230

    At this point, I think I will wait for a used one on my local forum.
    • Like Like x 6
  2. Armanius

    Armanius Bring Jack back!

    Jan 11, 2011
    Houston, Texas
    Real Name:
    Thanks for the test. That corner did look bad! But overall, it was nice for an improvised super wide.
  3. retow

    retow SC All-Pro

    Jul 24, 2010
    I recently tried the same adapter on the DP2M with promising results. Nr 2&3 show the left corners of Nr1.

  4. pinholecam

    pinholecam SC Regular

    Aug 3, 2012

    Yes, corners are a bummer...
    I did get very usable vertical FOV though and to me it makes a big difference in the photo composition.
    As in the case shown, more vertical space allowed the road and cross junction below to be seen adding to the leading lines towards the far end of the city.
    So if I crop to 8x10 format, it may still do 'ok'
    Very mixed feelings about getting this adapter, on the one hand the extra FOV is welcome, but the situations or conscious use of it to hide its problems poses a challenge.

    Certainly not problem free as I had hoped, so don't know if I should shell out the money for the adapter.
  5. pinholecam

    pinholecam SC Regular

    Aug 3, 2012
    Thanks for sharing.
    As I had suspected the DP2m does much better.
    Its the FOV like the DP1m but cropped much more, so I would think that its not affected much at all except for some minor IQ loss that can be 'brought back' by more aggressive sharpening.
  6. ivoire

    ivoire SC All-Pro

    Dec 3, 2011
    chicago burbs
    Real Name:
    Tks for the comparison. Was thinking of getting one for the DP2M. I'm finding them for $230 out of Japan but I think I'll wait n see if a used one comes up also