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85mm 1.4 focusing and sharpness issues


rascal64

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<p>Hi...I just bought a used 85mm 1.4 lens. I am a bit disappointed with the results, as this lens is supposed to be the crown jewel portrait lens. I shoot with a D300. I am not sure if my problem is the lens, the camera or me. Some of the images that I get, look great ...GREAT! But, the results are unreliable. I am getting soft focus on the eye, or an inaccurate focus a lot of the time. Does this lens lose center focus capabilities at 1.4? I have read that the D300 can calibrate individual lenses, but I don't know the first thing on how to do that, or if that is the answer. Here are 3 side by side images shot at 1.4. The focusing square told me that the eye (closest to the candycane)was sharp. These images are straight from the camera. RAW converted to JPEG. Should I return this lens? Any help would be appreciated!</p><div>00XkyP-306253584.thumb.jpg.8016ea50b2e7d8361e05ac62284af24d.jpg</div>
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<p>Tiffany, I agree with John.<br />An aperture like 1.4 results in a "Paperthin DOF" , therefore you cannot afford to let your camera choose the focussing point as it will find the highest contrast in the frame ( which happens to be the candybar here...).<br />If you realy did focus on one of your models eyes , using your center foccusing cell only, ( Single Point AF ) then I would say that you need to trim the focus "in camera" ( AF Fine Tune) ,but if you used multiple focussing points and allowed the camera to choose, then thiese pictures are just what i would expect with this lens..</p>
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<p>Don't return the lens! Obviously yours is in excellent condition. It is not uncommon for people to have focus difficulties with f1.4 lenses. I am sure someone with experience with this lens/camera combo will be able to help you with technical aspects of the equipment. Otherwise experiment and manage/refine your technique.</p>
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<p>C.P.M.....I am shooting on Single Point AF. I have the settings at 9 points for the dynamic AF area. I am not sure if by having it in single point AF, that 9 point setting applies. The option in my autofocus menu only shows fine tuning for exposure. I am not sure where the fine tune focus is.</p>

<p>Matt....we have actually done some test shots of me (I can be quite static) and it seemed like the eyes were soft in half of the images. I was probably between 7and 10 feet from the girl in the posted shots.</p>

<p>John....I was really excited to get this lens. It was a great deal, but still pricey (for us). There was a little gunk in the lens that doesn't seem to appear in images, but we are wondering if it might affect the focusing quality. Believe me...I really would like to have this lens as part of my kit, but I also want something reliable. I am willing to do the work...I just need to know what the work is.</p>

<p>Andrew...I moved back a bit for the last shot. For the first 2, I was pretty stable. The girl was seated and I gave her the same direction in between shots.</p>

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<p>Tiffany,<br>

I agree with Matt that those shots are not good for testing. You should redo the test in better condition: flat subject with details like a newspaper, higher shutter speed and camera is on tripod</p>

<p>But right now my guess the reason is the lens is in bad condition</p>

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<p>Tiffany, did you capture those images at f1.4? I never quite understand why people shoot portraits @ f1.4. No lens is at its best so wide open and the depth of field is very shallow such that most of the image is guaranteed to be out of focus regardless of where your focus is.</p>
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<p>John...we did some new test shots. We even did it the way the youtube vid said. With the coke can and changing all my camera settings...tripod...sandbag. The results seem okay. I was a little alarmed that the "lens sharpness chart" claims that this type of lens is only sharp at 2.0, 2.8 and 4.0 (if I am understanding the info correctly). I also don't shoot coke cans, I shoot people, so we tried again with myself as the subject. And as Shun pointed out, we shot at several apertures...because 1.4 portraits are quite ambitious and maybe a bit foolish? But, going back to 1.4, this is what happened. My husband was focused on my eye (no smart comments guys, please).</p>

<p>Shun, I don't plan on shooting a lot of 1.4 portraits, but it should focus where we tell it to, right?</p>

<p>Luis...It is a wonderful lens. Again, this one was used. No box, no hood. It may be trouble. We have a week to decide if we are returning it or not.</p><div>00Xl9C-306419684.thumb.jpg.d7e3126ff405c48d5df432d3304c9a54.jpg</div>

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<p>Tiffany,<br>

You must fine tune your focus manually with a fast portrait lens. As Shun says, the depth of field is maybe less than an inch thick at 1.4. And if you focus on the eyes as you should, you need DOF of 2-3 inches to keep the nose in as well as the ears.<br>

Stop down to 2.8 and you will get maybe 4 inches or more. You'll get the hang of it. For portraits, I always focus manually. By the time you have fiddled with selecting a focus point and getting it onto where you want to focus, you would have taken the shot, packed up and gone home if you did it manually.</p>

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<p>The strange thing is that the result is not consistent (and I guess because of the condition of the lens). There are big differences between the two photos. On the left photo, your eyes and your right half body are sharper. On the right photo, your left half body is sharper starting from the hair under your left ear</p>

<p>This inconsistency is in the photos of the little girl too. Her face and the candy bar are sharper in the photo on the left, but her left shoulder is sharper in the photo in the middle, the photo on the right is kind of an average of the other two photos</p>

<p>I still suggest using a newspaper as the subject (not the coke can)</p>

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<p>I wouldn't be too concerned about no box on a used lens. I still have the boxes and warranties for lenses I bought 20 years ago (we even have boxes for items we no longer own), but I know not everybody has space for boxes and that kind of discipline. No hood is an alarm, though. That means the previous owner(s) has not been using it and we all know how important the hood is in terms of lens protection.</p>

<p>f1.4 lenses are always difficult to focus. I own no f1.4 AF lens. You can try focus fine tuning and see whether that can fix the problem. Or if you can depend on manual focusing, change to a focusing screen that has split-image focus assist. Otherwise, with the new 85mm/f1.4 AF-S coming onto the market, I would imagine that there should be plenty of the old version on the used market once some people start upgrading.</p>

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<p>Tiffany, keep the lens. As stated a couple of times earlier, the DOF is so shallow at f1.4 that the slightest body sway either by photographer or subject will change the point of focus. Check out an online depth of field calculator such as "DOFMaster". It provides accurate focusing distances for a ton of lenses. I'm guessing you were about 8 feet from the camera in your second set of test shots. With the 85mm f1.4 on a DX camera at 8 ft. from subject, the resulting depth of field is .15 feet or approximately 1 3/4 inches.<br>

The 85mm will provide excellent bokeh at smaller apertures as well so if critical focus is required for non static subjects I'd stay away from f1.4</p>

<p> </p><div>00XlFA-306511584.jpg.4ce1855ae95c806c2823c4476290023c.jpg</div>

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<p>Hi Tiffany, as to portraits and f: stops. The pictures of the girl: with a 85-105 lens in order to get the tip of the nose as well as the earlobes in focus the f: stop must be at least 5.6. This applies to head shots. The candy cane is much further forward than the girls head. Also manual focus on the eyes. Fine tuning the lens via the D300 menu only applies to autofocus. Regards Peter</p>

 

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<p>Somewhere around Nov 5th there was a thread in the wedding forum about manual focus. One of the main things that came to mind in writing my response was focusing on the eyes in portraits and how I am never happy with the auto focus for this. If close enough, the AF will zero in on part of the nose or eyelashes or whatever. If I'm closing down the pupils and lighting up the color in the eyes, I want the eyeballs themselves really in focus. I don't use the 1.4, I use th 1.8 which I've had a long time. I think f2.8, f4 is not unreasonable in many cases, the DOF is so narrow. When I shoot musicians at jazz clubs and coffee-houses, I always work with an old small manual 50mm 1.8 and my 85mm 1.8 wide open and manual focus. I don't like the 50 1.4 wide open, while it's brighter to see, it's not sharp enough wide open. So while the 1.4 have really nice "bokeh" (oh, I can't believe I used that word....) sometimes I don't think they are the optimum choice when actually shooting wide open. Another lens I like to use wide open is the 180mm 2.8 and also the Hasselblad 100 f3.5 and 180 f4. You certainly have many very fine images, so you know what you want, but perhaps this isn't quite the tool. Maybe you'd be happier with the smaller lighter and less expensive f1.8? If you think the lens is a dud, get rid of it before it's a liability, lol.</p>
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<p>At f1.4 on a smaller sensor at a distance of 10 feet, the DOF is about 2.5 inches with an 85mm lens. Any change of distance between the subject and the camera (subject moving just a little bit and/or the camera moving just a little bit) will soften the focus considerably. I sounds like you are using spot autofocus so that should help, but another thing you could try (not sure this is supported on the D300) is to put your camera in continuous focus mode with the release set to 'focus' What this will do is release the shutter the instant the camera thinks it is in focus and reduces the two step focus and then shutter release to one step. I use this method a lot because I tend to move the camera just a bit on the two step process going to shutter release.<br>

I guess the other thing I might say is for me, the 70-200 f2.8 VRII lens is the go to portrait lens. Probably 85% of my portraits are taken with that lens and I do own the 85mm f1.4 lens. I once did a comparison between the two lens for sharpness and at 85mm, could not convince myself I could tell the difference between the two lens and AF was much better with the 70-200. If anyone would like to see the image set, I will figure out a way to get them to you.</p>

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Is this the new G lens or the old afd?

 

Either way with the razor thin dof expect to gets some out of focus shot unless the subject is static just how many depends on which version you have. My D700 (same af module as your D300) nails the af fairly reliably with the adf version wide open but if there is any movement or you are focus/recomposing forget it.

 

I have found that even with better than 20/20 vision, the D700 viewfinder with split image screen my af nails the focus more accurately than I can manually focus and I've come from MF/LF cameras.

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<p>Is the Autofocus mode setting selection on © Continuous or (S) Servo? If it's on S then focus may/will be locked on the first squeeze of the shutter button. If any sway occurs then the focussed plane will not move even if the subject/photographer does, resulting in apparent focussed plane error. <br>

If it's on C, then the camera should take account of these movements and use the actual focussed length at the second of exposure.</p>

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<p>On the D700, there are two steps. First is to set the autofocus switch to C (Continuous), and then in the menu items there is an Autofocus--> AF-C priority selection --> a) Release, b) Release plus focus, c)Focus. I set it to c or Focus as the criteria for shutter release. Not sure what the options are with the D300. Second step is important since if you select a) Release, the camera will take the picture whether or not you are in focus!</p>
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<blockquote>

<p>C.P.M....Oh...you are referring to the fine tune that Martin mentioned?</p>

</blockquote>

<p>Tiffany, the fine tune I am writing about is at page 327 of your user manual titled "AF Fine Tune"<br />There are many methods for "FineTuning" your cam's. AF for a specific lens, and you can do this for 12 lenses and keep the adjustments for them in your D300.<br />Here is a relatively simple method that works for me for my D300 & 85 1.4 AF-D lens .. : <a href="http://www.focustestchart.com/chart.html">http://www.focustestchart.com/chart.html</a><br />You can download the test charts at the end of the article..</p>

<p>BTW, I had a peek at your gallery, and I fully understand why you like this type of lens... Nice shooting !!! . :-) , a lot of "Dreamyness" mixed with expression and character going on there , very expressive i think !!</p>

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