Any 'prosumer' nikons that won't keep 'searching' when focusing?

<p>I am getting tired of my D5100 'searching' for a focus point--especially in low light. The action reminds me of an inexperienced driver attempting to parallel park in a tight space. I've tried all focus settings in various situations, and the only 'quick focus' environments seem to be in good natural light or studio strobe work with the continuous 'preview' lights on. A few ancillary questions are a) I can get sharp images at 1600 in good light conditions, but does that mean the focus will be achieved in low light where the setting (or higher) is needed, and b) I'm using an old novatron set-up that has preview lights. Would I achieve focus with speedlights in a dim indoor situation? Is there a Nikon model below $1,000 body only that would achieve more than a modest focus improvement?</p>

<p>Are you on normal VF AF or LV AF?</p>

<p>Initially my D5100 and D5300 would hunt like crazy when in LV AF until I found I needed to be in WIDE AF mode unless I was in amazing light and tripod mounted.</p>

 

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<p>b) I'm using an old novatron set-up that has <strong><em>preview</em></strong> lights. Would I achieve focus with speedlights in a <em><strong>dim</strong> </em>indoor situation?</p>

 

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<p>That doesn't quite make sense unless the Preview lights are real poor. However, if the flash has an AF Assist Light (Red Stripe projector) and you're in AF-S, Yes.</p>

<p>The centre AF point is the most sensitive, so focus and recompose may work for you.</p>

<p>Slow, ie f5.6, lenses make AF hard for most focus modules. Even using slow apertures from a fast lens in LV AF isn't so good.</p>

<p>I've had best results with f/1.4 lenses.</p>

<p><a href="https://www.keh.com/358741/nikon-d7100-digital-camera-body-24-1-m-p">You can buy a D7100 for under a grand now</a>. Under $900 actually. I like the focusing on the D7100, but it still needs good lenses to use well. </p>

A D7100 has a much better focus system than what you have. But another thing - if you're using the 18-55 lens in low

light, that's holding you back as much as the camera. Get a 35mm 1.8 DX lens and you'll see a huge improvement in low

light focus.

<p>The D5100 has the Multi-CAM 1000 AF module where only the center AF point is of cross type. If you want better low-light AF performance, restrict to that one AF point only and use a faster lens such as the 35mm/f1.8 Andy suggests above to let more light hit the AF module. I have a D200 that uses the same AF module with the same limitations.</p>

<p>If that is not sufficient, as suggested above, the D7100 is now around $900 and has 15 cross-type AF points: 5 each in the middle 3 columns. However, if you use the other line type AF points, it can still hunt under low light with a slower lens.</p>

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<p><em>However, if the flash has an AF Assist Light (Red Stripe projector) and you're in AF-S, Yes.</em><br>

<em>The centre AF point is the most sensitive, so focus and recompose may work for you.</em></p>

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<p><em><br /></em>IMO the assist light only works if you are in AF-S <strong>and</strong> only the center spot is activated</p>

<p>Mag: The D810 manual claims the AF-assist works with auto-area, though I don't know if this is true for the D5100. I guess the restriction on other points is there in case you're using a wide-angle and there's insufficient coverage from the AF assist light. (Good catch, though - I'd forgotten that this was a constraint.) The AF-S restriction is, I suspect, there because you're not really supposed to leave the light on indefinitely.</p>

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<p> The AF-S restriction is, I suspect, there because you're not really supposed to leave the light on indefinitely.<br>

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<p>Would be nice to have it as a user option with the SB-800 red projector or the SC-29. A couple of times in a dark church, I'm sure I've swayed <em><strong>after</strong></em> AF-S lock. A 'timer' option for 10/20 or even 30 seconds, would be simple enough.</p>

<p>Tiny red or green laser modules and those little grid projection lenses are pennies and barely eat any battery power.</p>

<p>The only important bit is it's not <em><strong>on</strong></em> at the moment of exposure!</p>

<p>A rather old-fashioned but very effective technique in complicated light is.... manual focus. However, the kitlenses have horrid focusrings, and the D5x00 viewfinder isn't great for it. But in a studio environment, manual focus is sometimes a pretty viable answer.<br>

Another thing is that whatever AF system you have, you do need some level of contrast for the system to focus on. If you have frontal, relatively flat, lighting, you may just miss the bit of shadows needed to generate the needed contrast edge for the AF system to pick up.<br>

That all said, yes, the D5200 already would be a nice step up for AF, and the D7100 even better.</p>

<p>I'll second the theory that it is as much the lens as it is the camera. A lens with a larger aperture allows more light in with which to focus.<br>

As the owner of a 7100 and a D80 (certainly worse focusing than the D5100), if I go into a low light room and put my 35 1.8 on the D80 and my 18 - 135 kit on the 7100, the D80 will focus fairly well and the 7100 will hunt. <br>

Before the feedback, yes i realize if I reverse the lenses and put the 35 1.8 on the 7100, it will focus far faster than the D80 did, and the D80 will be far slower than the 7100 was, but that's not the point here, only that the maximum aperture can significantly increase focusing in poor light.</p>

<p>I've had my D7100 actually focus using only moonlight with an f2.8 lens.</p>

<p>Kent in SD</p>

<p>Even with my Df (sold, traded down for $$ and a v. nice used D7000) I used center point only focusing and the AEL/AFL (set to lock focus only) to hold the focus and reframe. In great conditions the full AF program can be nice but as soon a tree branch intervenes you're back to the same "tyranny-of-the-electronics" situation as always. Once you get used to working with one point only it becomes second nature -- you find the spot you want to focus on, keeping in mind your depth of field in relation to your aperture, and lock it with your thumb. </p>

<p>One good technique is thumb focus. Set the AE/AF lock to focus and take focus of from shutter. Then you can compose very easy after focusing to the important point.</p>

<p><em>Thanks for the many good tips. I have been thinking about the D7100. I'm also experimeting with the AE/AF lock to focus, and also, as was recommended in one d5100 user guide, tilting the camera about 10-15 degrees to overide lack of contrast of desired target object, then reorienting for the shot.</em><br>

<em>Regarding fixed lenses, I have the Nikon 50mm f/1.8 AF-D which requires manual focusing for the lower end Nikons. Would the comparable 35mm nikon lens have any advantages? I like the 50mm since it approaches a portrait lens given the digital/film 1.5 ratio. I know that the relatively new Nikon 50mm AF-s f/1.8 G has an autofocus mode for the D5000 & D7000 series, but I've also read that it has noticeably more distoration. Does anyone know of any evidence regarding the latter claim. Any advice among choosing from among these three lenses? </em></p>

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<p>I know that the relatively new Nikon 50mm AF-s f/1.8 G has an autofocus mode for the D5000 & D7000 series, but I've also read that it has noticeably more distoration. Does anyone know of any evidence regarding the latter claim.</p>

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<p><em> </em><br>

I reviewed the Nikon 50mm/f1.8 AF-S for photo.net a few years ago: http://www.photo.net/equipment/nikon/lenses/50mm-f1.8-af-s-fx/review/<em><br /></em></p>

<p>In the review, I included an image of a swimming pool and the club house behind it. There is a tiny bit of barrel distortion but it is almost negligible: http://d6d2h4gfvy8t8.cloudfront.net/14310554-lg.jpg<br>

For the purpose of portraits, even a large amount of geometric distortion from the lens is a non-issue. The more important issue is that if the camera it too close to the subject, the nose and face will look distorted as the nose will look big while the face will be swelling a bit. Most people find such effect undesirable.</p>

<p>If the 50mm focal length has been working for you, why not upgrade to the AF-S so that it can AF with the consumer-grade DSLRs? It is only a bit over $200 and f1.8 will certainly help AF under dim light.</p>

<p>Hello Shun,</p>

<p>I just read your review. I'm pretty much convinced now that I should purchase the lens. Thanks for your input.</p>

<p>Alan</p>

<p>Glad I can help. If you are already happy with the 50mm AF-D, upgrading to the AF-S to gain AF with a D5000-series body seems to be the obvious choice. As far as I know, my people find the AF-S to be an improvement from the earlier versions, which I don't own.</p>

<p>However, 50mm still seems to be a bit short for portraits on DX bodies. You need to be careful not to get too close to your subjects.</p>