tamron 100-400 ..

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PhotoLover

PhotoLover

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I have this lens, paired with a Nikon d7500. I think it is a decent walk-around wildlife lens (light, some weather-sealing, lots of reach on a crop-sensor). Autofocus speed is okay, far from awesome. Images, especially on close subjects can be very sharp.

What I'm wondering about is how much of a penalty I'm paying in autofocus speed and accuracy because wide open the aperture is only 6.3 at 400. Supposedly once you get beyond 5.6 the autofocus won't work as well -- with 8.0 being considered a problem. But 6.3 is .... a little smaller than 5.6.... but not as small as 8.0.

What do people think of this lens in general?
 
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I have the lens, like it, and get some very sharp shots with it. AF speed seems okay, but not blazing. The thing is, I hardly ever use it since I much prefer my Nikon 200-500 even though it weighs a lot more. I also have an older Nikon 70-300 that is really light and reasonably sharp, so if I was smart I guess I'd sell the Tammy.

I was just playing around with this lens on a D500. I tried focusing with the lens at f/4.5 at 100mm, and I noticed that the focus speed is quite a bit faster than when I was at 400mm and f/6.3. Try this out and you might get an idea of the "penalty" for going to f/6.3.
 
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Woodyg3 said:
I have the lens, like it, and get some very sharp shots with it. AF speed seems okay, but not blazing. The thing is, I hardly ever use it since I much prefer my Nikon 200-500 even though it weighs a lot more. I also have an older Nikon 70-300 that is really light and reasonably sharp, so if I was smart I guess I'd sell the Tammy.

I was just playing around with this lens on a D500. I tried focusing with the lens at f/4.5 at 100mm, and I noticed that the focus speed is quite a bit faster than when I was at 400mm and f/6.3. Try this out and you might get an idea of the "penalty" for going to f/6.3.
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Woody,
Good suggestion on a test, though I might try at whatever zoom leaves me at 5.6.

Why do you like the 200-500 so much better? Brighter? More reach? Better autofocus? I rented the 200-500 for a week on a trip and thought it was probably better than the Tamron (aside from just the extra reach) though I couldn't do back to back on identical scenarios.

I did find the 200-500 a lot heavier. I have a decent shoulder strap, and can carry the Tamron around all day with it. With the 200-500, it felt heavy after a couple of hours.

I have a 16-300 Tamron for a walk around lens, and I find 300 just isn't enough reach for a lot of things, even on a crop-sensor.
 
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PhotoLover said:
Woody,
Good suggestion on a test, though I might try at whatever zoom leaves me at 5.6.

Why do you like the 200-500 so much better? Brighter? More reach? Better autofocus? I rented the 200-500 for a week on a trip and thought it was probably better than the Tamron (aside from just the extra reach) though I couldn't do back to back on identical scenarios.

I did find the 200-500 a lot heavier. I have a decent shoulder strap, and can carry the Tamron around all day with it. With the 200-500, it felt heavy after a couple of hours.

I have a 16-300 Tamron for a walk around lens, and I find 300 just isn't enough reach for a lot of things, even on a crop-sensor.
Click to expand...

Yep. f/5.6 a tad brighter, More reach, better autofocus, sharper at the long end.
 
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PhotoLover said:
I did find the 200-500 a lot heavier. I have a decent shoulder strap, and can carry the Tamron around all day with it. With the 200-500, it felt heavy after a couple of hours.
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I use a strap harness that carries the camera/lens on my chest if I'm going to be out for a while with a heavy lens. It helps a lot.
 
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I have two of these finding the 200-500 was too heavy. You must do the tap in console . Its easy using the auto fine focus adjust on the D850. You will be amazed at the variations over the 16 readings.
My two lenses are totally different ..one is very + and the other -.

Adjusting makes a big difference if you use at 400mm to do close ups but if the FFA is out you will never be happy.
The OPs comments are a bit strange ..whatever the aperture its set at it always focuses at its widest and stops down for taking the photo
 
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Pistnbroke said:
The OPs comments are a bit strange ..whatever the aperture its set at it always focuses at its widest and stops down for taking the photo
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Right, and that's his point. The smaller the maximum aperture the more difficult it is for the camera to autofocus due to decreased light. So, not a strange comment at all. :)
 
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Woodyg3 said:
Right, and that's his point. The smaller the maximum aperture the more difficult it is for the camera to autofocus due to decreased light. So, not a strange comment at all. :)
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I think I did word my comment badly. But yes that is what I was trying to say.

I did know that the camera focuses wide open and then stops down when actually taking the picture. :)

But I thought it wasn't so much the reduced light, but that the smaller aperture was physically blocking some of the sensors ..... I'll double-check.
 
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Pistnbroke said:
I have two of these finding the 200-500 was too heavy. You must do the tap in console . Its easy using the auto fine focus adjust on the D850. You will be amazed at the variations over the 16 readings.
My two lenses are totally different ..one is very + and the other -.

Adjusting makes a big difference if you use at 400mm to do close ups but if the FFA is out you will never be happy.
The OPs comments are a bit strange ..whatever the aperture its set at it always focuses at its widest and stops down for taking the photo
Click to expand...
I have the tap-in console but confess I haven't used it. However, looking at shots taken at different distances, I can't find any clear evidence of front or back focus.

But I do know it is very sharp for closeup (400mm, 5 to 15 feet) but I'm not quite as confident of the results at longer distances. Still, I took one shot today of a Blue Heron taking off from about 30 yards that was pretty sharp.

I should go calibrate though -- I use the lens all the time, no reason not to ensure I'm optimizing performance. Sounds like you found it worth the trouble.
 
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Andy Work said:
I use a strap harness that carries the camera/lens on my chest if I'm going to be out for a while with a heavy lens. It helps a lot.
Click to expand...

Thanks, I'd already figured after renting the 200-500 for a week that if I bought one, I'd also be investing in more strap :)

Is there a brand you recommend? I have a Blackrapid shoulder strap and think it is really good.
 
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PhotoLover said:
I think I did word my comment badly. But yes that is what I was trying to say.

I did know that the camera focuses wide open and then stops down when actually taking the picture. :)

But I thought it wasn't so much the reduced light, but that the smaller aperture was physically blocking some of the sensors ..... I'll double-check.
Click to expand...

This what Steve said in his ebook on Secrets To the Nikon autofocus:

"Often, people think the F/5.6 or F/8 autofocus limitation is there because of the decrease in the amount of light coming through the lens. While that’s a small part of it, it has far more to do with the physical blocking of image information to the micro lenses and AF module."
 
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