Forgot Password
Pentax Camera Forums Home
 

Reply
Show Printable Version Search this Thread
12-29-2015, 01:18 PM   #1
Senior Member




Join Date: Apr 2015
Posts: 127
Lots of front focus

After not being totally happy with the results of shooting with my DA 35, I recently got a lens calibration thingy and performed some fine adjustments with it. I was able to dial in a certain amount of fine adjust to get the resulting shots to match up with the AF's notion of in focus. I did this on the single point focusing mode so I could be absolutely sure of what it was deciding was the focal point of the image. I then decided to roll on to my DA 50, then each of my DA zooms, and I'm finding that every single one of them front focuses to different degrees, but I don't know if this it something that I should be concerned with. I had to go to 10 on my 50 and I wish I could still push it a little further.

Recently I picked up a manual lens and I'm finding that it's having a similar problem; I can't trust what live view shows for focus peaking. As if white focus peaking were in any way useful to begin with.

Thoughts?

12-29-2015, 01:27 PM   #2
Veteran Member
manntax's Avatar

Join Date: Jan 2012
Photos: Albums
Posts: 1,972
QuoteOriginally posted by disord3r Quote
After not being totally happy with the results of shooting with my DA 35, I recently got a lens calibration thingy and performed some fine adjustments with it. I was able to dial in a certain amount of fine adjust to get the resulting shots to match up with the AF's notion of in focus. I did this on the single point focusing mode so I could be absolutely sure of what it was deciding was the focal point of the image. I then decided to roll on to my DA 50, then each of my DA zooms, and I'm finding that every single one of them front focuses to different degrees, but I don't know if this it something that I should be concerned with. I had to go to 10 on my 50 and I wish I could still push it a little further. Recently I picked up a manual lens and I'm finding that it's having a similar problem; I can't trust what live view shows for focus peaking. As if white focus peaking were in any way useful to begin with. Thoughts?

I don't know what to add about your DA lenses apart from the fact that from the very beginning (ok, from K10D) the front- or back- focusing was an Achilles heel of every Pentax's dslrs (maybe newer K3+ don't have this as serious but still they do need some adjustments). About focus peeking I similarly find it confusing and constantly inaccurate on any camera I tried. Call me weird but I just cannot see where the focus supposed to land on that thing ! So I resorted to magnification in live view, which for my needs is most accurate way of confirming focus.
12-29-2015, 01:33 PM   #3
Pentaxian
mikeSF's Avatar

Join Date: Jan 2009
Location: East Bay Area, CA
Photos: Gallery
Posts: 5,541
i find focus peaking to be incredibly useful. Are you saying you are getting inaccurate or inconsistent results?
12-29-2015, 01:34 PM   #4
Senior Member




Join Date: Apr 2015
Posts: 127
Original Poster
QuoteOriginally posted by manntax Quote
the front- or back- focusing was an Achilles heel of every Pentax's dslrs
At least it's consistent.

Do you know if the Adjust All value stacks with the Adjust One setting? I tried to put Adjust All to 3 so that I could subtract 3 from all my Adjust One values. That would put my DA50 at 7 and give me a bit more headroom to adjust it up to 10 if I needed. Didn't seem to make a difference.

---------- Post added 12-29-15 at 03:38 PM ----------

QuoteOriginally posted by mikeSF Quote
i find focus peaking to be incredibly useful. Are you saying you are getting inaccurate or inconsistent results?
The manual lens has no AF, obviously, so I went to live view to make sure I was focusing well; the moire that happens on the live view against the calibration cards various lines made it easy to make sure I was focused exactly where I wanted to be. I got it focused well at 0.6x on the live view zoom, and in the shot it has front focused.

I honestly didn't try corroborating the live view with the AF on any of my DAs, so I don't know if they have the same issue. I got around to the manual lens last and kinda gave up thinking that I wasn't doing this right.

12-29-2015, 02:02 PM   #5
Veteran Member
manntax's Avatar

Join Date: Jan 2012
Photos: Albums
Posts: 1,972
QuoteOriginally posted by disord3r Quote
I honestly didn't try corroborating the live view with the AF on any of my DAs, so I don't know if they have the same issue. I got around to the manual lens last and kinda gave up thinking that I wasn't doing this right.
try focus bracketing in small incremental moves - this way you can learn what the properly focused image looks like on the screen. Moire pattern is not an indication - it is more a combination oif detail + contrast what I look for. Never have issue with focusing in live view with manual glass this way. Focusing peeking is useless for me though
12-29-2015, 02:34 PM - 1 Like   #6
Pentaxian
aleonx3's Avatar

Join Date: Jul 2007
Location: Brampton, Ontario
Photos: Gallery | Albums
Posts: 3,873
Just curious, do you realize that using viewfinder and Liveview to focus are not the same? as one uses PDAF and the other uses CDAF; separate focus mechanism on the camera.
12-29-2015, 02:57 PM   #7
Senior Member




Join Date: Apr 2015
Posts: 127
Original Poster
Yes, but it should still be "in focus" if live view shows it, shouldn't it? Camera on tripod, stationary subject, both deliberately positioned, well lit, etc.

But yeah, I definitely could be reading the live view wrong in the case of the MF lens.
12-29-2015, 03:10 PM   #8
Site Supporter
jatrax's Avatar

Join Date: May 2010
Location: Oregon
Photos: Gallery | Albums
Posts: 10,289
QuoteOriginally posted by disord3r Quote
Yes, but it should still be "in focus" if live view shows it, shouldn't it? Camera on tripod, stationary subject, both deliberately positioned, well lit, etc. But yeah, I definitely could be reading the live view wrong in the case of the MF lens.
There is no adjustment for liveview, it is from the sensor and is in focus. So if you are getting inaccurate results you might be reading things wrong. Or using too small an aperture, I'm not sure how accurate it is at small aperture values.

The viewfinder AF is another story and can be adjusted. One method of adjusting is to compare it to the Liveview AF as that is considered to be dead on If all of your lenses are showing a consistent result then it is possible the camera is off a bit and could be adjusted at the service center. Whether you want to go to that trouble and time (and possible expense) is up to you. I feel if it is within the fine tune adjustment I'm OK. But YMMV.

12-29-2015, 05:45 PM   #9
Pentaxian
Sagitta's Avatar

Join Date: Feb 2011
Location: Maine
Photos: Gallery
Posts: 2,912
Regarding focus peaking - turn on the highlight alert (same section of the settings that the focus peaking option is in). Your white sparklies of the peaking will be interpreted as blown highlights and the camera will make them flash red in the LCD.
Reply

Bookmarks
  • Submit Thread to Facebook Facebook
  • Submit Thread to Twitter Twitter
  • Submit Thread to Digg Digg
Tags - Make this thread easier to find by adding keywords to it!
adjust, af, da, focus, front, k-30, k-50, lens, live, lots of front, pentax k30, pentax k50, view
Thread Tools Search this Thread
Search this Thread:

Advanced Search


Similar Threads
Thread Thread Starter Forum Replies Last Post
For Sale - Sold: LOTS and LOTS of Pentax Stuff - K-01 still available - MUST GO! DRabbit Sold Items 11 09-22-2014 03:06 PM
Sigma 24-60mm - lots of spots on the front element Quicksand Pentax SLR Lens Discussion 13 08-31-2009 04:51 PM
How to put lots of tag on lots of pictures in flickr? Andi Lo General Talk 10 06-27-2009 02:49 PM



All times are GMT -7. The time now is 07:23 AM. | See also: NikonForums.com, part of our network of photo forums!
  • Red (Default)
  • Green
  • Gray
  • Dark
  • Dark Yellow
  • Dark Blue
  • Old Red
  • Old Green
  • Old Gray
  • Dial-Up Style
Hello! It's great to see you back on the forum! Have you considered joining the community?
register
Creating a FREE ACCOUNT takes under a minute, removes ads, and lets you post! [Dismiss]
Top