Site Sponsors
Results 1 to 17 of 17

Thread: Truefocus Problem

  1. #1
    Member
    Join Date
    Mar 2010
    Location
    Switzerland
    Posts
    206
    Post Thanks / Like

    Truefocus Problem

    Hi to all, I have a question because I do not now what I should do, or what you will do in the same situation. I had my new H4D-40 for about 11 weeks (!) in Danmark to calibrate the backfocus. After this long time the focus is now spot on. But the TrueFocus works not as he should... The sujet is soft, because the correction from the TF should be more and the sharpness is more behind. When I correct the TF manually some mm, then you see nearly the "tack sharp" picture (how Hasselblad promised) which anyway could be better. So, what you think should I do?
    Thanks for your experience and statements! rem

    you can see in the pictures the hole situation and the single frames...



    maybe I will post this also in the Hasselbladforum...

  2. #2
    Super Duper
    Senior Member

    Join Date
    Nov 2007
    Location
    Royal Oak, MI and Palm Harbor, FL
    Posts
    8,498
    Post Thanks / Like
    Images
    44

    Re: Truefocus Problem

    Which lens? Are you on a tripod?

    What part of the bottle label are you focusing on?

    Are you focusing TF using the rear TF button?

    Are you locking TF and releasing the TF button before panning?

    -Marc

  3. #3
    Member
    Join Date
    Mar 2010
    Location
    Switzerland
    Posts
    206
    Post Thanks / Like

    Re: Truefocus Problem

    Hi Marc,
    yes the cam was on a tripod with a hc 80/2.8 at 3.5. The focus was on the "A" from Costasera (center of the label). Locking with the rear button and releasing it before panning. The wheel from the TF in the display was always turning. lg rem

  4. #4
    Senior Member
    Join Date
    Apr 2009
    Location
    Sydney, Australia
    Posts
    581
    Post Thanks / Like
    Images
    2

    Re: Truefocus Problem

    Have you spoken to your dealer?
    Cheers,
    Jeff
    www.jeff-grant.com

  5. #5
    Member
    Join Date
    Mar 2010
    Location
    Switzerland
    Posts
    206
    Post Thanks / Like

    Re: Truefocus Problem

    Jeff, not yet. I was waiting so long for the camera while she was in Denmark. When I checked months ago with my dealer the back-focus problem then we checked also the true-focus function. He said it will be more a marketing gag Hasselblad.... Then we tried his h4 and the difference was night and day. And he was stunning...;-) So, you now why I ask the cracks here. For me is clear that it works with my camera not how Hasselblad say. I will also contact Hasselblad tomorrow direct with some pics. lg,rem

  6. #6
    Senior Member
    Join Date
    Apr 2009
    Location
    Sydney, Australia
    Posts
    581
    Post Thanks / Like
    Images
    2

    Re: Truefocus Problem

    That's the way to go. One thing is certain, Hasselblad stands by their products.
    Cheers,
    Jeff
    www.jeff-grant.com

  7. #7
    Super Duper
    Senior Member

    Join Date
    Nov 2007
    Location
    Royal Oak, MI and Palm Harbor, FL
    Posts
    8,498
    Post Thanks / Like
    Images
    44

    Re: Truefocus Problem

    Well, as they say in Texas ... "That dog don't hunt."

    Hardly a "marketing gimmick", True Focus/Absolute Position Lock works like a charm for off-center focus ...

    Here are a couple of hand-held shots demonstrating it action (sorry for the boring test shots). the tree limb was shot with a 150/3.2N wide open @ ISO 400 ... both would have been even better on a tripod.

    Have your dealer contact Hasselblad and let them know you need priority service after the camera was gone for so long ... ridiculous IMO.

    -Marc

  8. #8
    Senior Member
    Join Date
    Jan 2010
    Posts
    528
    Post Thanks / Like

    Re: Truefocus Problem

    It amazes me that your dealer is referring to TF as a marketing gimmick... he either never tested himself or only got broken bodies.

    TF works and it works really well. I can place the sharpness anywhere I want in the frame.

  9. #9
    Member
    Join Date
    Mar 2010
    Location
    Switzerland
    Posts
    206
    Post Thanks / Like

    Re: Truefocus Problem

    Dustbak, since we tried out with his h4d, he know it works!;-)
    Marc thank you for the samples! I was playing today to much with this TF problem. I postet some new pics on the Hasselblad Digital Forum. What do you think about the theory from Morgan on the Hasselblad Forum (Marc, because you said it would be better from the tripod...). I must say my pics are made from about 80cm (2.5"). In longer distances the problem would go... lg, rem

  10. #10
    Member
    Join Date
    Sep 2010
    Posts
    111
    Post Thanks / Like

    Re: Truefocus Problem

    If you are only 2.5" away, you're expecting an awful lot out of the TF feature. Your DOF is extremely narrow at that distance.

    I would imagine it's not really meant for macro application.

  11. #11
    Senior Member
    Join Date
    Jan 2010
    Posts
    528
    Post Thanks / Like

    Re: Truefocus Problem

    I think the theory TF works less well on a tripod because the point of pivot is different makes sense.

    Actually I find TF works really well handheld even very close-up and with a wide aperture. Next time I am working in the macro realm I will try to see how it performs.

  12. #12
    Super Duper
    Senior Member

    Join Date
    Nov 2007
    Location
    Royal Oak, MI and Palm Harbor, FL
    Posts
    8,498
    Post Thanks / Like
    Images
    44

    Re: Truefocus Problem

    Quote Originally Posted by rem View Post
    Dustbak, since we tried out with his h4d, he know it works!;-)
    Marc thank you for the samples! I was playing today to much with this TF problem. I posted some new pics on the Hasselblad Digital Forum. What do you think about the theory from Morgan on the Hasselblad Forum (Marc, because you said it would be better from the tripod...). I must say my pics are made from about 80cm (2.5"). In longer distances the problem would go... lg, rem
    Nodal point.

    My tripod rig includes a RRS sliding rail to properly place the lens' Nodal point directly over the center axis of the tripod, so when I pan side to side or tilt up and down, the actual focal distance to the sensor doesn't move forward or backward.

    True Focus-Absolute Position Lock doesn't adjust for forward or backward movement ... no AFs system does. Care in shooting technique is essential with any AF system ... especially considering the depth of field being less with a MFD fast lens relative to 35mm. TF is no different.

    TF actually is more apparent when shooting closer subjects off-center because any lens exhibits less and less depth-of-field at any f-stop relative to shooting more at a distance. Unfortunately, shooting closer also increases the need to minimize body sway.

    With TF one must pay specific attention to minimizing body sway while repositioning the frame composition. One thing that helps is to recognize that once TF locks you do not have to keep pressing the rear button. Then learn the shooting technique of recomposing by using your right hand (camera grip) wrist as a rigid pivot point and your left lens hand to do the moving ... all without moving your arms, or allowing body sway by using a good stance.

    I've become pretty good at this steady stance business because I routinely use a M9 with a 0.95 Noctilux wide open and up-close ... and just about any amount of body sway what-so-ever = out-of-focus


    -Marc

    For what TF/APL does do ... have a read:

  13. #13
    Workshop Member
    Join Date
    Nov 2007
    Location
    Brooklyn
    Posts
    4,043
    Post Thanks / Like
    Images
    1253

    Re: Truefocus Problem

    Marc: do you know the size of the autofocus spot? in the Victor document, for example, how big is the spot compared to the doll's eyes?

  14. #14
    Super Duper
    Senior Member

    Join Date
    Nov 2007
    Location
    Royal Oak, MI and Palm Harbor, FL
    Posts
    8,498
    Post Thanks / Like
    Images
    44

    Re: Truefocus Problem

    Quote Originally Posted by jlm View Post
    Marc: do you know the size of the autofocus spot? in the Victor document, for example, how big is the spot compared to the doll's eyes?
    No I don't know ... and I don't know how big the doll actually was, or at what distance the camera was from it.

    I normally just center the critical focus point inside the brackets located inside the etched circle.

    I have had zero critical AF issues with any of the H kits ... so far

    -Marc

  15. #15
    Member
    Join Date
    Mar 2010
    Location
    Switzerland
    Posts
    206
    Post Thanks / Like

    Re: Truefocus Problem

    Thank you Marc. Where we can see the nodalpoint? I was thinking the camera calculate the difference in distance... So I was not reading something about the nodalpoint in the brochure. But maybe its only ny bad english. It would be great when Hasselblad is thinking about the german speaking clients. You have with every 100 SFR Cam a manual in several languages but Hasselblad do that not offer... English would be fine for many things, but when its very technical or so then the mother language is much more better!;-) Do you have a pic from your setup? I postet one in the HD Forum and the head is pretty high... Thanks Marc!

  16. #16
    Super Duper
    Senior Member

    Join Date
    Nov 2007
    Location
    Royal Oak, MI and Palm Harbor, FL
    Posts
    8,498
    Post Thanks / Like
    Images
    44

    Re: Truefocus Problem

    Quote Originally Posted by rem View Post
    Thank you Marc. Where we can see the nodalpoint? I was thinking the camera calculate the difference in distance... So I was not reading something about the nodalpoint in the brochure. But maybe its only ny bad english. It would be great when Hasselblad is thinking about the german speaking clients. You have with every 100 SFR Cam a manual in several languages but Hasselblad do that not offer... English would be fine for many things, but when its very technical or so then the mother language is much more better!;-) Do you have a pic from your setup? I postet one in the HD Forum and the head is pretty high... Thanks Marc!
    It really doesn't matter hand-held ... what matters is to try and not move the camera forward or backward much when rotating/recomposing the framing ... like slightly leaning forward or backward.

    Remember, when you use TF it locks that point of focus, and then the camera's AF adjusts as you recompose. If you locked focus even with the subject in the center with out TF, then moved slightly back or forward ... it would be out of focus ... same for TF.

    -Marc

  17. #17
    Member
    Join Date
    Mar 2010
    Location
    Switzerland
    Posts
    206
    Post Thanks / Like

    Re: Truefocus Problem

    Yes I understand now how the system works... Thanks Marc! And TTLCurtis, the 2.5" means 2.5feet (80cm). Sorry for wrong writing. No Macro...;-) rem

Tags for this Thread

Posting Permissions

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