cheat card for tamron 70-300

blooming34

I was given this lens a few months ago, would I be okay using the 18-55 lens cheat cards? I could not see a card with these figures.

bruto

I think you might get closer with the cheat card for the 55-300. I don't know what the apertures are on the Tamron you have, but guidelines for the focal lengths involved will be nearly the same, and chances are pretty good that the apertures are similar. The basic rules don't vary all that much.

When the D3200 was introduced, Nikon did not make a DX format 70-300. Their full frame 70-300 was very good but rather big and expensive. They now do make a 70-300DX but it will not work (even a little bit) with the D3200 owing to its newfangled focus system. The 55-300 was not awful, but a little soft at 300 and its auto focus was not very good, so if your 70-300 is fairly new and focuses decently, you're likely well equipped.

Depending on the age of the lens, one discrepancy might be in whether your lens has vibration stabilizaton (VR, IS, or whatever Tamron calls it). The VR on the 55-300 is pretty good, and the cheat card instructs to turn it on.

If your lens does not have any VR, a general guideline for DX cameras is to try to keep the shutter speed at or above 1.5 times the focal length. So, for example, at a focal length of 70 millimeters, you would want a shutter speed of ~ 1/100 second or faster. At 300 millimeters, you would want something in the vicinity of 1/500 or faster, to avoid camera vibration.

If your lens does have VR you can reduce that by some, depending on how well it works. If it has, for example, VR that's good for three "stops," that would mean that you could cut the shutter speed in half three times. Each stop being a halving or doubling. So one stop down from 1/500 would be 1/250, another stop down 1/125, and so forth. Exact amounts will vary a bit with operator, so you should experiment. If you're shooting wildlife, you will probably need high shutter speeds anyway in order to stop subject motion even if you can hold the camera steady, so its always good if you can to err on the side of faster. For many of the applications in the cheat card it's probably about right anyway.

I am assuming that the Tamron you're getting is new enough that it has an integrated focus motor. If it is an older one with "screwdriver" AF, then it won't auto focus with your D3200 and you'll have to focus manually. Still useable but not so convenient for things like birds in flight. The focus confirmation dot still works for manual focusing lenses, but the small viewing screen makes precise focusing a bit of a challenge. If you have real trouble, the DK-21 focusing magnifier helps a lot. But if you have working AF it should be fine.