Forgot Password
Pentax Camera Forums Home
 

Reply
Show Printable Version Search this Thread
03-12-2016, 10:43 AM   #46
Site Supporter
stevebrot's Avatar

Join Date: Mar 2007
Location: Vancouver (USA)
Photos: Gallery | Albums
Posts: 27,297
QuoteOriginally posted by slip Quote
Example of what I am talking about you couldn't hit the eyes the way the K3 I set up https://www.pinterest.com/pin/25684660351127709/
NOT my shot!
I am not registered with pinterest. What I saw, before being cut off by the site, was a gallery of head/torso portraits with all elements (face, hair, ears, shoulders, clothing, etc.) in acceptable* focus (i.e. not f/1.4 work). Based on the perspective, I estimate the subject distance of about 10 feet. At that distance and f/5.6 or f/8, focus/recompose should work very well as might SEL-9 skewed to include head/shoulders. If AF locks on the nose, lips, or eyes the rest will follow based on DOF alone. Manual focus using the viewfinder would also be quite effective.


Steve

* Meaning appropriate for print media, computer screen, posters, or hang-able prints at standard viewing distances for each.


Last edited by stevebrot; 03-12-2016 at 11:00 AM.
03-12-2016, 12:33 PM - 1 Like   #47
Loyal Site Supporter
monochrome's Avatar

Join Date: Mar 2008
Location: Kirkwood (St. Louis) MO
Photos: Gallery | Albums
Posts: 20,341
QuoteOriginally posted by stevebrot Quote
What I saw, before being cut off by the site, was a gallery of head/torso portraits with all elements (face, hair, ears, shoulders, clothing, etc.) in acceptable* focus (i.e. not f/1.4 work). Based on the perspective, I estimate the subject distance of about 10 feet. At that distance and f/5.6 or f/8, focus/recompose should work very well as might SEL-9 skewed to include head/shoulders.
At 10' and f/5.6 using an 85mm portrait lens the acceptable sharpness zone ranges from 9.35' to 10.7', or 1.4'. Assuming the model's eye is 40% into the acceptable range, the focus point should be 7" inside the near boundary of acceptable focus, leaving 10" behind the model's eye to the rear boundary of acceptable focus - or essentially the ear, hair and decolletage also in acceptable focus.

I'm not up on current taste in wedding portraits so I can't comment on the necessity to shoot at f/1.4 but I'm quite convinced at f/5.6 current digital camera autofocus systems using SEL-9 can find something within the range of acceptable focus that will allow the eye and entire head and shoulders to be acceptably sharp.

But that's just me. I'm just an old-school Spotmatic film guy whose journo teacher insisted in 1971 I mount a 105, leave it on f/5.6 and move my feet. Maybe the problem is the new, computer-designed flat, sharp to the corners lenses. Funny thing is, in 1999 my daughter's journo teacher taught exactly the same thing. But they were using K1000's and M100's and the Journalism Curriculum was decidedly old-school.

Last edited by monochrome; 03-12-2016 at 12:39 PM.
03-12-2016, 12:47 PM   #48
Site Supporter
stevebrot's Avatar

Join Date: Mar 2007
Location: Vancouver (USA)
Photos: Gallery | Albums
Posts: 27,297
QuoteOriginally posted by monochrome Quote
At 10' and f/5.6 using an 85mm portrait lens the acceptable sharpness zone ranges from 9.35' to 10.7', or 1.4'.
...and at that distance, a head/torso shot such as in the examples from the pinterest gallery would be done with a 50mm lens on APS-C with even deeper DOF.

As with many threads of this nature, the use case for "deficiency" becomes increasingly narrow as the discussion progresses. I too don't know who routinely does autofocus portraits at f/1.4, but I suppose those people are out there somewhere. I am also dubious that any of their cameras are able to consistently provide accurate focus using PDAF at faster than f/2.8. I would expect that it would be easier to shoot at f/5.6 and blur as needed in PP.


Steve
03-12-2016, 12:52 PM   #49
Site Supporter
stevebrot's Avatar

Join Date: Mar 2007
Location: Vancouver (USA)
Photos: Gallery | Albums
Posts: 27,297
QuoteOriginally posted by monochrome Quote
...and decolletage...
Yes please...


Steve

03-12-2016, 01:03 PM   #50
Loyal Site Supporter
monochrome's Avatar

Join Date: Mar 2008
Location: Kirkwood (St. Louis) MO
Photos: Gallery | Albums
Posts: 20,341
QuoteOriginally posted by stevebrot Quote
Yes please...


Steve
There's usually a lot of embroidery and pearls on the bridal gown there, so we need it to be sharp, n'est-ce pas?
03-12-2016, 01:21 PM   #51
Forum Member




Join Date: Feb 2012
Posts: 63
I am currently renting a K-3 II for the weekend. From a landscape photog perspective, I can tell you the K-3 II viewfinder AF points do not cover a wide enough area for many shots. The VF images I saw for the K-1, likewise, do not appear spread out enough. And focus / recompose is a hassle on a tripod. That said, the live view on the K-3 II has a larger AF area and I was able to use that. If only it had a tilt screen like the K-1. Bring on the K-3 Mark 3 please...

Last edited by Zen4Life; 03-12-2016 at 01:26 PM.
03-12-2016, 01:29 PM   #52
Loyal Site Supporter
monochrome's Avatar

Join Date: Mar 2008
Location: Kirkwood (St. Louis) MO
Photos: Gallery | Albums
Posts: 20,341
QuoteOriginally posted by Zen4Life Quote
The VF images I saw for the K-1, likewise, do not appear spread out enough.
If you are shooting some kind of subject element positioned significantly out of the center area, and you want shallow DoF for subject isolation, yes, you will need to either manual focus or focus and recompose on the tripod. A panning ballhead or pan / tilt head (or gimbal) will help. So you want AF points spread all the way out to the margins?

PF K-1 VF Image with all projections showing (including the black crop frame):


Like the D810?

Nikonians.org image:



You're right - Pentax isn't there yet. The Nikon AF points appear to be more densely packed, but spread similarly to the K-1 VF. There are just more of them.

Adam says Pentax are unlikely to ever catch up with Nikon because Nikon are not sitting still. But this is a significant step.

For my use on K-3 selecting one of the cross-type AF points has been acceptable, and it appears that will suffice on the K-1.

Last edited by monochrome; 03-12-2016 at 02:11 PM.
03-12-2016, 01:30 PM   #53
Moderator
Loyal Site Supporter
BigMackCam's Avatar

Join Date: Mar 2010
Location: North East of England
Posts: 6,567
QuoteOriginally posted by Zen4Life Quote
I am currently renting a K-3 II for the weekend. From a landscape photog perspective, I can tell you the K-3 II viewfinder AF points do not cover a wide enough area for many shots. The VF images I saw for the K-1, likewise, do not appear spread out enough. And focus / recompose is a hassle on a tripod. That said, the live view on the K-3 II has a larger AF area and I was able to use that. If only it had a tilt screen like the K-1. Bring on the K-3 Mark 3 please...
With landscape photography, do you find yourself using AF a lot? I don't have a great deal of experience with landscapes, but a lot of what I've read seems to suggest MF for hyperfocal distance is preferable. Do you prefer AF, and if so, why? It's a genuine question, by the way - not a criticism of your method

03-12-2016, 01:50 PM   #54
Pentaxian
pete-tarmigan's Avatar

Join Date: Apr 2009
Location: Conception Bay South, New-fun-land
Photos: Gallery
Posts: 1,007
Can someone point to threads that discuss what purpose ≥100 autofocus points is designed for? Tracking moving subjects in sports?
03-12-2016, 02:07 PM   #55
Loyal Site Supporter
monochrome's Avatar

Join Date: Mar 2008
Location: Kirkwood (St. Louis) MO
Photos: Gallery | Albums
Posts: 20,341
QuoteOriginally posted by pete-tarmigan Quote
Can someone point to threads that discuss what purpose ≥100 autofocus points is designed for? Tracking moving subjects in sports?
There's dozens of them - but the general sense I get (not an action shooter at all) is the tracking AF uses groups of AF points, and the algorithm calculates and predicts where the subject will move - so the AF points on the margin of the active group anticipate the movement and actually start to calculate focus before the subject is even targeted by them.

Last edited by monochrome; 03-12-2016 at 02:43 PM.
03-12-2016, 02:14 PM   #56
Forum Member




Join Date: Feb 2012
Posts: 63
Here is, perhaps, an extreme example and I do realize this is an EVF but checkout the new Sony A6300 focus point area. LOL, would satisfy everyone (425 phase detect points) :

http://petapixel.com/assets/uploads/2016/02/autofocuscoverage.jpg

Last edited by Zen4Life; 03-12-2016 at 02:21 PM.
03-12-2016, 02:26 PM - 2 Likes   #57
Veteran Member
maxfield_photo's Avatar

Join Date: Mar 2011
Location: Cincinnati, OH
Posts: 1,215
QuoteOriginally posted by monochrome Quote
So you want AF points spread all the way out to the margins?
Yes, please, and while you're at it, would mind terribly raising the flash sync speed to 1/500th?

Thanks in advance
03-13-2016, 11:53 AM   #58
Forum Member




Join Date: Oct 2009
Location: North Oregon Coast
Posts: 89
First thing I do with a new camera is switch to single center point AF.

Lock in focus & recompose if need be - Love it!
03-14-2016, 03:08 AM   #59
Forum Member




Join Date: Jun 2015
Posts: 59
QuoteOriginally posted by clackers Quote
Sorry, Randy, as a focus and recompose guy, I just need one very good AF point in the centre. It's all I want for sports, too, in AF-C.

Hey, I tried some sports photography with polo yesterday. Now this field I am like a novice. Never really did. But I was impressed with how afc with 9 point selection thing held the focus.

But I was really not impressed with ISO performance. With arena lights, it's so tough to get the motion to stop while having a lower shutter speed. I felt for polo to stop horses motion, about 1/500 was necessary. But had to crank up the ISO to 6400! and very grainy.

Would I need a faster lens for this. I usually do portraits travel and catalogue shoots. So my lenses don't go beyond 50mm. I had 18-135 so tried this polo game on that.

If suppose I get a faster lens like 200mm 2.8, would 2.8 give me problems in depth of field? Any tips?
03-14-2016, 06:56 AM   #60
Pentaxian
Dan Rentea's Avatar

Join Date: Sep 2014
Location: Bucharest
Posts: 624
QuoteOriginally posted by stevebrot Quote
I am not registered with pinterest. What I saw, before being cut off by the site, was a gallery of head/torso portraits with all elements (face, hair, ears, shoulders, clothing, etc.) in acceptable* focus (i.e. not f/1.4 work). Based on the perspective, I estimate the subject distance of about 10 feet. At that distance and f/5.6 or f/8, focus/recompose should work very well as might SEL-9 skewed to include head/shoulders. If AF locks on the nose, lips, or eyes the rest will follow based on DOF alone. Manual focus using the viewfinder would also be quite effective.


Steve

* Meaning appropriate for print media, computer screen, posters, or hang-able prints at standard viewing distances for each.

His name is Dani Diamond, he's known for his natural light portraits and for his retouching technique (see the links below).

Dani Diamond – NYC Fashion & Commercial Photogapher
https://www.youtube.com/user/dd1photos/videos

He uses a Nikon D800 and most of his portraits are taken either with Nikon 85mm f1.4 or with Sigma Art 50mm f1.4

The regular f stop on his portraits shots is around f1.4 - f2.2 and he use single selective Af. He can't use focus and recompose technique because he will miss a lot of shots because of the DOF (at least he said so and I tend to agree with him). I'm also a focus and recompose type of photographer for 80% of photographs, but for product photography I tend to use selective focus.

He had for a couple of weeks a Pentax 645Z in his hands but although he loved the dynamic range, the colors and the resolution of the camera he didn't kept it because he said he had a lot of miss shots because of the Af (he said it was inconsistent at wide aperture). We will find more about that soon because he will write an article about his experience with 645Z and he will publish it on Fstoppers.

Spread area of focus points it's good for a few reasons mentioned above by other forum members. For example a friend of mine is using a lot the selective focus when he photograph jewelry (focus stacking I think the technique he uses is called).

Last edited by Dan Rentea; 03-14-2016 at 08:07 AM.
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!
af, camera, dslr, focus, landscapes, lot, mf, photography
Thread Tools Search this Thread
Search this Thread:

Advanced Search


Similar Threads
Thread Thread Starter Forum Replies Last Post
Bluetooth, why is it so difficult? hks_kansei General Talk 8 10-11-2015 10:51 PM
Why is the K7 so terrible? or rather why am i having such a problem with it? runslikeapenguin Pentax DSLR Discussion 60 05-01-2012 01:16 PM
Autofocus? Why is it so slow? systemA Pentax DSLR Discussion 42 12-05-2008 07:32 AM
So, how hard is it to use Manual lenses? cputeq Pentax DSLR Discussion 19 04-18-2008 03:27 PM



All times are GMT -7. The time now is 12:25 AM. | See also: NikonForums.com, CanonForums.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