85mm 1.4 focusing and sharpness issues

[bebu_lamar]

<p>I think the problem is that the camera or subject moved slightly after the focus is locked and thus the lens is actually focused at a different plane than the one the focus is locked on.</p>

[shadforth_stephen]

<p>Don't fight it...fine tune the focus manually. Why is there so much resistance to that? Or are we becoming pig headed about autofocus everything.<br>

Why is this so hard? Is it something to do with some subliminal resistance to days of yore when one finger did the focussing instead of a nice fat AFS lens not getting it quite right.<br>

I don't understand...portraits are like landscapes. One sets them up, takes care with no rush and takes maybe three or four with some exposure bracketing. Nothing has changed in the art of portraits. Only the film has been swapped for the sensor. You still have to do everything else.<br>

With a good lens like the one you have, switch to manual focus and start with the eyes, then carefully stop down from 1.4, one click at a time, and watch the dof deepen until you have it just right. There will be a point when the nose and ears are sharp, or whatever you want, and then you have it.</p>

[ShunCheung]

<p>Shadforth, modern DSLR's viewfinders are not designed for manual focusing. I currently have 20/15 above average eyesight, but since I was a teenager 30+ years ago, I always need to have a split-image focus assist to manual focus. A few years ago I tried the Zeiss ZF 50mm/f1.4 on my D2X, and I found that electronic rangefinder pretty much useless. I had the same issue with my Contax 645 whose film size and focusing screen size is almost 3 times the FX frame, and yet I also had manual focusing issues until I bought their split-image focusing screen.</p>

<p>Today, the best way to manual focus on DSLRs is to use live view and magnify a small portion of the image to fine tune the focus; that approach works great for landscape and macro. Otherwise, I think getting one of those Katz Eye screen with split-image assist is a must for manual focusing.</p>

<p>And if you have ever capture portraits of children, especially small ones younger than 5, 6 years old, you'll understand that it is not like landscape photography at all. The live view approach is not applicable when your subject wouldn't stand/sit still.</p>

[shadforth_stephen]

<p>Yes, Shun. Three weeks till I get my D700.<br>

I'm spoilt by the finder in the F4s.</p>

[ilkka_nissila]

<p>In addition to a Katz Eye screen, calibration of the screen is often necessary. There is a hex screw on the right side of the mirror of the D700, which is used to calibrate manual focusing. Use a focusing target to determine if the screen gives front or backfocus.</p>

[rascal64]

<p>Wow...thank you to everyone who has offered input on this. I used the lens again on a job with my other lenses as primary. I used my tripod. I shot a 2.0. My camera is always set to "focus", not "release". I don't trust my own eyes for manual focus right now. I will do some more tests with that one. I had the same results. A few of the images were beautiful...several more...soft or misfocused. My husband has a gut feeling on this lens and I certainly need something reliable. I am willing to push myself and learn how to use new tools, but I have to make sure it's a good tool. We are talking about returning the lens and using the $ towards a new 85mm. However, I am going to do a few test shots (before we buy) with the new one and see if I have the same problem. If I do, then I know I have to work a bit harder or just enjoy my 50mm 1.8 (which is a star!). I have a lot to reread here. Again, I really appreciate all the input.</p>

[stevenseelig]

<p>If you really have questions about the specific lens, perhaps you can find a local place to rent the same version of the lens. I have rent lens on several occasions, and generally, have been quite happy with their performance.<br>

When you focus on the eyes, do you focus on the section of the eye closest to the noise or the outer portion of the eye?<br>

I am not sure how large of an area the D300 uses to generate a focus, but I would guess the autofocus area marked in the view finder is larger that the space actually used.</p>

[CvhKaar]

<p> Steven, good point, when focussing on an eye, i like to focus on the line of the eye and the lower eye lid ( is that what you call this in english? ) because the eye itself makes focussing hareder by being to reflective. <br>

Also when using my 85 1.4, for portrets I like to set it to F2 mostly, because at 1.4 the dof is too shallow causeing a blurry nose tip when focussing on the eye often,, ( do i live in "big nose country ?? :-) ) .</p>

[stevenseelig]

<p>At least on the D700, the outer focal points only look for lines in one direction (horizontal or vertical) to operate the autofocus functionality. With the camera in the vertical position, it is very difficult for the camera to focus on a horizontal line (eyelids) on any but the center focus point. In fact, it won't. If you rotate the camera about 25-30 degrees, it will instantly focus with the focal points outside of the center ones. Not sure what the D300 does, but you might check that as well.</p>

[ShunCheung]

<p>The D300 family, D700, and all D3 family DSLRs use the same Multi-CAM 3500 AF module. That is why their AF works pretty much the same way.</p>

[CvhKaar]

<p> Steven, I agree with you there, but it works for me to just focus with the center focus point on the lower eyelid, ( I use the af control , not the shutter control for focussing always), and then recompose if neccesary. Mostly both eyelids also have hairs attached. .:-) , which help a bit if needed.<br>

Like I sayd, it works for me, and it works for me a lot better then focussing on the eye itself ( if vissible..), but everyone will have hers or his way of doing things I guess...</p>

 

[sjmurray]

<p>I don't have an 85mm lens, but I shoot regularly with 50mm f1.4, 105mm f 2.5, 35mm f 2.0 lenses and all of them are difficult to focus on a dslr. I never use any of these lenses wide open unless I'm in very dark conditions and have to. With portraits even with the 50mm I use f2-2.8 to get good sharpness and still have a nice blurry background. With the 105mm I usually use about f4 for a portrait. All these fast lenses are softer wide open and as noted the depth of focus is really narrow and difficult to control. I would try some portraits using more f stops to see how they look in terms of sharpness and bokeh. It is a nice focal length for portraits. </p>

[scott_murphy_photography]

<p>I use an 85mm f/1.4 AIS Nikkor quite a bit for portraiture and the depth of field wide open is <em>paper thin</em>. Using a lens like this is just one more reason why I <em><strong>NEVER</strong> trust a camera to focus for me</em>. That's for point and shoots. With a lens like this, especially in a static environment like yours, you should always focus manually. Only you know exactly what you want focus on. And in the case of your photos, focus on the catchlights in the eyes.</p>

<p>Digital camera focusing screens, however, are not particularly well suited to manual focusing, as most are simple matte screens. I would recommed you change your screen to something made by focusingscreen.com to something with either a microprism or split image (or combination of the two) focusing aid. Those folks have a wide selection of screens for a large number of cameras. And even though they are designed to help focus manually, they will still work perfectly with your camera's autofocus.</p>

<p>The selection of screens for the D300 can be found here: <a href="http://www.focusingscreen.com/index.php?cPath=22_76&osCsid=8de58811644604eceb9a9e8b5f0310cd">http://www.focusingscreen.com/index.php?cPath=22_76&osCsid=8de58811644604eceb9a9e8b5f0310cd</a></p>

[sjmurray]

<p>Another observation, Tiffany, is that most of your portraits have very little background and its often a studio background with little detail. With this type of shooting you don't need a lens with excellent out of focus (bokeh) qualities, since it won't show anyway. An AF kit lens of the desired focal length would work just as well and be less headache focusing. I think of the classic portrait lenses such as the 105 f2.5 and the 85 1.4 as lenses you would use when there is a background that you want to render as soft and pleasing. Here's an example of the 105mm on a full frame film shot probably at about f 4: http://www.photo.net/photo/1522609</p>

[andreshiwa]

I bought the 85mm Art on January during a trip to Doha/Qatar.

The focus was totally inaccurate. After tons of shots with the 5D Mk IV in a tripod I could identify part of the nightmare - up to 1m showing front focus, after 2.5m show back focus.

Then, I bought the usb dock to try "calibrate" the focus. After everything updated I was ready to start

It just make grow a strong anger - totally inconsistent... in 3 or 4 shots at least in two the focus area was in different point.

I reset and start again countless times.

As I live in Brazil and bought during the trip, I can not return the copy. The Sigma assistance here is NOTHING.

It was my second Sigma lens, and was worse than the first experince.

I gave up

SIGMA NEVER, NEVER MORE !!!!!

[Sandy Vongries]

2010 Reanimated? Why? Zombie post.

[mike_halliwell]

Sadly, Sigma and Canon have never played well together regarding AF.

 

Why this has been resurrected in the Nikon forum 7 years later is just another of life's mysteries!

[Andrew Garrard]

Huh. In that case, the original might have been about an 85mm AF-D. (The original post did seem to be about Nikon, it was just the recent post talking about Sigma that was on Canon.) I hope the 85mm Art behaves okay on Nikon - I've had a bit of trouble with the 35mm and 50mm, but the 85mm and 135mm f/1.8 are on my wish list.

 

 

I've no idea how these old threads keep coming up. The view I have of the forum seems unambiguous - although an alternative "when did the thread start" view wouldn't hurt. That said, the old forum's search system was almost unusable, so maybe people are actually trying to use the new one (which I never have) and that's why we're seeing resurrections.

[jde]

Did you write the Japanese manufacturer???

[rodeo_joe1]

Canon? 2010?

 

I still think a course in effective reading is called for!