brooklyn-camera I Loc: Brooklyn, NY

Designed for APS-C-format DSLRs. I purchased it and have used it with my 7D MKII. I think it is a so,so lens. Nothing to write about....this lens can't compare to Canon L glass. Very soft at the long end.....
Tried shooting a football game from the sidelines and end zones and the photos just weren't tack sharp. Even shooting at 1/1000 f/6.3 and an ISO of 200.

jerryc41 Loc: Catskill Mts of NY

Volume! How many cameras have Canon and Nikon made, compared with Sony DSLR production? The more Nikons there are, the more lenses they can sell. I'm sure a Sony model will be along soon.

How many aftermarket accessories are made specifically for the Bugatti Veyron? With so few owners, the R&D and production would be wasted.

PhotoPhred Loc: Cheyney, Pa

I have one and it is on my Nikon d7100 almost all the time.

olemikey Loc: 6 mile creek, Spacecoast Florida

With a "sharpest one you can find an example of" superzoom, the in camera crop of the D7xxx series or Sony Clear Image Zoom gives me a solid shot with sufficient MP's and sharpness for "most" long shots, while still having the somewhat wide capability. Would I buy an 18-400 for the right price, YES I would. Would I pay full retail, NO, I don't "need one", but I would like one. Would I rather have a super duper prime, of course.

mas24 Loc: Southern CA

The reason behind the Tamron 18-400mm lens not being available for Sony A-mount, is that the projected sellings didn't look good for profits. It would be for crop sensor. And the E-mounts are for Sony crop and full frame cameras. Maybe later, when the Sony a77iii is released. And sellings determine if one should be produced. For A-mount. Forget about E-mount. It won't happen. Not even for any of the a6000 series.

Zooman 1

I have the Tamron 18-400, had the 16-300 sent it back, vowed not to buy another Tamron, but decided to get the 18-400 after reading reviews. Have had good and poor results, find the 18-50mm range not very sharp for landscape type images, but OK for closer work. Have a problem with the lens not focusing @ 400mm every now and then, have to zoom back to around 100mm to get focus again, AF or M does not matter. Sent it to Tamron for repair, but lens was sent back with a note that there was nothing wrong with it. Also have the Canon 70-300, which makes for me anyway a better walk around lens.

Strodav Loc: Houston, Tx

First thing to do is check whether you need to tune or not. I am familiar with Nikon dslrs, but not others, so this is what I have done for my 4 Nikon bodies, 2 DX, 2 FX. Live View uses a different method of focusing than AF mode (contrast (slow) vs phase (faster)). Live View shows the best the camera and lens can do (if you use good technique). So, I take images of a resolution chart in LV and AF. If they match, congratulations, you have confirmed AF is fine. If the AF image is softer, then you might want to tune.

Next thing to do is determine is whether your AF system is focusing in front of or behind the intended focus point. This can be done by shooting a page of text, focusing in the center of the page, like a newspaper page, at 30 to 45 degrees, i.e. front (closer to lens) of the page lower than the camera lens and back of the page higher than the camera lens. Look at the image to see if the text is in focus in front of or behind the focus point.

My dslrs have a AF fine-tune feature where you can move the AF point forward or backward. Nikon's only have one adjustment per lens, but I thought I heard Canons have two adjustment points per lens. In any case read your manual. For Nikon, go to the AF fine tune menu item and you will see a -20 to +20 adjustment range. By default it's at 0. A negative number moves the focus point towards the lens and a + value move the focus point away from the lens. I usually move 5 units at a time. It's trial and error, but with time and patience you will walk it in. So AF fine-tune is in the camera body and only has one (2 Canon) adjustment points per lens. For modern Sigma and Tamron lenses which use the usb dock or tap-in, you can tune at multiple points in the lens itself. For the 18-140mm in this post, there are 24 different points to tune, 3 different distances and 8 different zoom factors.

Important. When taking test shots use a sturdy tripod, remote release, aperture wide open (shallow DOF), turn off VR (if any), AF mode still (not continuous), single focus point, always take at least 3 shots. Before taking every shot, manually move the focus ring off a bit so you are forcing the system to re-focus before every shot. AF is a random process. It does not go back to the exact same point every time, which is why you need to take at least 3 shots and compare them.

Chris T Loc: from England across the pond to New England

First off, DL - you have to have the USB Dock. Once you have that, you plug it into the PC with the attached USB cable. There will be another cable with the Dock - which gets plugged into the little port on the side of the lens barrel. Do you see it, DL? … Then you download software onto your PC, and using the software - you set about the process of fine-tuning the lens - with your chosen camera. I THINK, but, I don't know for sure - the process will have to be repeated, for every camera you own. I suspect, though, the differences amongst the same brand, will be infinitesimal … but, I am not really sure. If I bought it in Nikon mount - it seems I might have to do it, as many as five times. If I got the Canon version - I'd have to retune 3x. Noted above in another response - the tuning turned out to be the same - with the 24MP D7200 as it was - for the 20MP D500 - which has me wondering … not sure it could be exact. Anyway ….

Chris T Loc: from England across the pond to New England

Have you fine-tuned yours, with the USB Dock, M?

Chris T Loc: from England across the pond to New England

Serj - the 16-300 is a different animal entirely. That one is a VC PZD. This one is a VC HLD. So, it uses an entirely different AF mechanism than the earlier Tamron - apart from knocking out the lower 2mm and adding 100mm to the top. Pricewise - they're approximately the same - around $650 … but, to be honest, I have seen the earlier model at around $495 - which is a $155 difference!!! … What I'm trying to find out, here - is whether that difference makes sense to invest - which it might - if it's significantly better … ok?

Chris T Loc: from England across the pond to New England

But, don't forget, Brooklyn - you were shooting a moving target with a fairly heavy lens. Even though it's designed to be handheld - I think optimum sharpness, full out, is only achieved in ideal situations - say - plenty of light, and a non-moving target. You have to make allowances for that kind of situation. Perhaps, had you used it on a tripod - you might have gotten better IQ. Canon L glass is much better, of course - but most of them are twice the weight, AND TWO - make that THREE times the price!!! You get what you pay for!!!

Chris T Loc: from England across the pond to New England

Well, Jerry … I compiled a list, recently - of All Sony ILC models - and the total on that list is 45!!! … Now, let's see - Nikon has the D5, D850, D750, D810, D610 (FX) and the D500, D3500, D5600 - all DX - how many's that? Eight. Canon has the 1DX II, 5D S, 5D S R, 5D III, 5D 1V, 6D II (FF) and the 7D Mk. II, the 80D, the 77D, the SL2, the T7i, and the T7 (APS-C) - how many's that? An even dozen!!! … Tamron can't count, obviously ….

Well, Jerry … not everyone can afford a Bugatti … but, most folks - here in the US - can afford a Sony!!!!

Chris T Loc: from England across the pond to New England

Hey, Phred … say - did you take that gorgeous pic of your oh so gorgeous cat with it? If so - fantastic!!!

I have the D7100, too … so this 18-400 Tamron is a good match for it - is it?

Chris T Loc: from England across the pond to New England

Mike - unfortunately, this lens is not yet made in Sony a-mount. So, more's the pity! … Wouldn't that be great? … Just switch on the CIZ and you're out to 800mm instantly! … Better still - switch on the DZ - and now you're out to 1600mm!!!! … Yes, well - super duper primes are gonna cost you a whole lot more than the $650 this jewel will cost ya. But, hey - you can put it on a Nikon. Get the USB dock - and you'll probably wind up with better performance than that 70-300 will give you!!!!!

Chris T Loc: from England across the pond to New England

Mas - the prior Tamron 16-300 VC PZD was / is - available for Sony a-mount. Since Tamron established a precedent with THAT lens - it makes no sense to me, they didn't continue that trend with THIS lens. Yes, the a77 and a65 and a58 (most recent Sony APS-C models) - were all discontinued, but they added the a68, and the a77II and a99 II (FF model) - are selling like hotcakes!!!!