Non-BIM vs BIM lenses?

[jiawei_zhang]

<p>I've searched everywhere for this but no one seems to know whether the d90 af speed is good or not. For example, will the Tamron 28 75 2.8 Non-BIM<br>

<a href="http://www.newegg.com/Product/Product.aspx?Item=N82E16830997648">http://www.newegg.com/Product/Product.aspx?Item=N82E16830997648</a></p>

<p>focus faster or slower than the Tamron 28 75 2.8 BIM<br>

<a href="http://www.amazon.com/Tamron-28-75mm-Aspherical-Built-In-Digital/dp/B001955P8W/ref=sr_1_3?ie=UTF8&qid=1336101540&sr=8-3">http://www.amazon.com/Tamron-28-75mm-Aspherical-Built-In-Digital/dp/B001955P8W/ref=sr_1_3?ie=UTF8&qid=1336101540&sr=8-3</a></p>

<p>Can someone please tell me which one is faster focus since the optics are both the same. What about the focusing noise? Will the NON BIM be softer? Thanks so much.</p>

[andylynn]

<p>The non-BIM lens is powered by the focus motor in your camera. What camera is it? The BIM version isn't particularly fast, so the non-BIM one is likely to be a bit faster. Noise on the non-BIM is comparable to other screwdriver lenses. For the BIM version there is noise - it's not a silent motor. I never listened to them side by side but I think the BIM is a bit quieter than the screwdriver on cameras I'm used to.</p>

<p>Check the used market for these. I have a non-BIM one that I got used for $250, which was a pretty amazing value considering how well the lens does on my F100 and D700.</p>

[jiawei_zhang]

For a d90, which would be faster?

[richard_thomas9]

<p>Back then when I had a D90, I used to have both the BIM non VC and non-BIM 17-50 version. Problem with the BIM non VC that it hunts too much in low light and takes longer to lock focus than my non-BIM. Hence, I ended up keeping the non-BIM. I believe if you Google the BIM Non VC vs Non-BIM Tamron's, a lot of owners share the same opinion as mine.</p>

[leslie_cheung]

<p>The difference is probably small enough where it won't make much of a difference (lens hunting for both lenses) in a dark gym. If you are a bit paranoid about it...Buy both and see for yourself. Then return the one you don't want. Problem solved.</p>

<p> </p>

[rodeo_joe1]

<p>I have the Tamron 28-75 "G" version with built-in motor. It's <em>much</em> quieter than other screwdriver focusing lenses I have, but it's not absolutely silent.<br>

I can't do a direct speed comparison with a non-BIM 28-75, because I don't have one anymore - I did have, but had to return it because of an optical defect. From memory the BIM version is faster and more accurate. DISCLAIMER (YMMV): This may just be my impression, but I'm pretty sure any speed difference will go in favour of the BIM version. The light has to be really low to cause it to hunt as well. Anyway, either version is a nice lens if you get a good copy.<br>

I use a D700 BTW.</p>

[eric_arnold]

<p>the BiM is a micromotor. not as fast as a screw-drive on some bodies. on a D90 it may or may not make a difference either way. i would probably get the non-BiM in case you upgrade your body to a camera with a more powerful focus motor like a d300 or d700, which will drive a screw-drive lens faster than a micromotor. btw the 28-75 is a great lens, but the 17-50 is probably better for DX unless you specifically need the 50-75mm range (, i.e., for portraits).</p>

[stank]

<p>On my D70s, the Tamron BIM was not much different than the non-BIM. I also hunting with the Tamron BIM. When it didn't hunt, it seemed to focus quickly to almost perfect then fine tune the focus slowing the process. In comparison, the Nikon AF-S lenses (18-105, 16-85) were faster focusing than both Tamrons.</p>

<p>Since I needed AF speed for sports, I upgraded to a D300 over the D7000 mainly for the better internal AF motor. On AF-S lenses, they were essentially equal.<br>

Stan</p>

[eric_arnold]

<blockquote>

<p>On AF-S lenses, they were essentially equal.</p>

</blockquote>

<p>stan, if i'm not mistaken, the 16-85 and 18-105 are consumer-grade AF-S. you would probably see a difference with a pro-spec lens like the 70-200 or 24-70. 18-55 is also consumer grade.</p>

[jiawei_zhang]

<p>So, on your Nikon d70, the BIM is faster than the Non-BIM? I have a d90. I went to the store today and they had only the BIM version and it seemed to focus with about the same speed as the Nikon 18-200 with the cap on. Since I really had no way to test the low-light functionality of the autofocus, I need to ask again, is it fast enough to photograph moving dancers on a dimly lit stage? If the BIM does, then I'll get the BIM since it is likely I'll be getting a d3200 soon as well so the motor will be nice. Choices choices choices...The only place I can still find the Tamron non-bim new is on newegg and it seems to be running out fast, so I need to decide...</p>

[rodeo_joe1]

<p>If there's enough light to take decent pictures, there'll be enough light for the autofocus to work. I think those people that complain about focus hunting must be working in near-darkness where they can hardly see to compose the image, and I bet if they turned on the camera's AF assist illuminator they'd have no trouble.</p>

[stank]

<p><em>"So, on your Nikon d70, the BIM is faster than the Non-BIM? "</em></p>

<p>It was a tough call but the Tamron non-BIM seemed to focus slightly faster than the Tamron BIM as it didn't seem to hunt as much and it did not do the fine tuning. It went immediately to focus. The Nikon AF-S was faster. In the end I settled on a Sigma 17-70 OS with HSM (BIM) which seems very comparable in speed to the Nikon AF-S. </p>

<p>I also have an old Nikon 70-210 AF-D which is non-BIM and focuses very quickly (faster than the Tamron 70-200 w/BIM) and is super fast on my D300 body. </p>

<p>I haven't tried all modern Tamrons but I think they make some fine optics. However, their AF servo systems could use a little more work. I am impressed with the Nikon AF-S and Sigma HSM focus speed.<br>

Stan</p>