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I don't know why, but I have been especially anxious about receiving this lens. It could be due to my new found appreciation for the fast, super telephotos. It may be the sheer size of these beasts and an accompanying gratification that I am getting, at least in weight, what I paid for. Whatever the reason, it has arrived!
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The Tamron SP 400mm f/4 LD-IF (65B) Adaptall lens is somewhat of a rare lens. After a lot of shooting with the Tokina 300mm, I realized I often attach the 1.4x teleconverter and just about always shoot at f/4 or more (f/2.8 is bit too soft). Because of this, I began looking for possible alternative prime lenses which were somewhere in the ballpark on price but perhaps a little more tailored to longer shots. I checked out some of the 300mm f/4 lenses too, which can be had for relatively meager prices these days, even with AF. But again, 300mm is a bit short and when considering I will want to use TCs to extend whatever lens I use (because why not always have the option for that little extra reach) somehow 300 2.8 and 400mm f/4 seemed to be the cut-offs. I was mainly looking at the Nikon 400mm f/3.5 but I have just been having a hard time finding one that hasn't been beaten to a pulp and isn't 2 grand. There is hardly any info out there on the Tamron SP 400mm and it was pure chance that I stumbled across this one.
Specifications
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Model: 65B
Aperture Range: f/4-32
Angle of View: 6.2°
Optical Elements/Groups: 10/7
Min. Focus (From Film Plane): 118" (3.0 m)
Filter Size: 43mm (Rear), 112mm (Front)
Max. Diameter: 4.6" (118 mm)
Weight: 80.1 oz (2270 g)
Lens Hood: Bayonet #39FH
Physical/Cosmetics - First Impressions
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This is my first Tamron Adaptall lens, ever. I know nothing of their build quality but I believe they have a great reputation according to many of the forum posters with their Adaptall and Adaptall-2 line. My first thought when I pulled this lens out of the bubble wrap was it seemed...lighter than I expected. Sure, I could have just read the weight on the adaptall-2.com site (and I did). But it is just different when you are holding the lens in your hand. As stupid an observation as it may be, when you flick this lens barrel, or give it a little knuckle tap, sure it feels solid, but the Tokina literally feels like a brick made of metal. In that respect the Tokina 300mm MF just seems a bit more indestructible. But given the age of this lens, and its condition, I am not worried about it lasting because it is still a professional quality lens.
The second thing I noticed when mounting this lens is that there seems to be a tiny bit of play in the setup. I have read a few reviews in various forums describing this lens as being poorly constructed, or at least less than ideal and specifically making comments about the adaptall mount. The adaptall mount system is universal. I think it is brilliant for a third party manufacturer; that is, in its more conceptual form. Making a lens mount system that can truly adapt to many brands, that is equal to an original OEM mount is a great undertaking. I think Tamron did very well! Yes there is some play in the mount. But I have used teleconverters with more play than this mount has. So this issue is acceptable to me. Also, the tripod mount on my lens is faintly ajar. I may be able to tighten this via the four visible screws. I only noticed when I mounted this lens on the tripod and even after being secured there was a faint bit of movement. The bayonet hood is another source of less than perfect tolerances. Being tension mounted, the hood doesn't sit 100% locked in place. Once the flanges clear the retention springs, the hood has a fraction of a millimeter to move. These issues are relatively small but I note them because I have not seen these types of mechanical shortcomings in my Tokina 300mm, my only comparably lens as of now. So despite the esteem of the optics and the price, don't expect to be wowed by the build.
It is possible all these slight inaccuracies are a result of wear over time. I am perfectly fine with that explanation. Because quite honestly, none of these factors affect the optical performance in any way. They may contribute to the overall confidence factor that a photographer feels about his or her gear. Design issues can be indicative of the mechanical reliability. I have only owned the lens a day and cannot comment on this yet. Though I can say, I have seen posts in the forums of photographers claiming others may take their Tamron 400mm f/4 "when they pry it from his or her dead, lifeless hands". So in the end, I'm not too worried!
Stylistically, I love the look. The Tamron 400mm comes in the same military greenish tan color as its sibling the Tamron SP 300mm f/2.8 LD-IF (060B) telephoto lens (Another lens I would love to try). I find the unique turquoise ring (Tamron's little design queue denoting Low Dispersion glass) an excellent retro touch. The adaptall mount system is a great concept and so far isn't nearly as troublesome as many have made it out to be. Though, I have hardly used it in real-time and do realize that may make all the difference.
Some other features of the Tamron 400mm is a focus limiter. When shooting, you can dial in a point of interest such as home plate at a ball game. You can then quickly focus the lens to that point when necessary. It seems both the 400mm and the 300mm Tamron LD-IF telephotos originally came with a small palm rest accessory. The palm rest is a small knurled hardened plastic part that attaches to the base of the lens via the tripod socket used to make steadying the lens more ergonomic. I find it surpisingly useful!
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I also received the original Tamron canvas bag that was marketed with the SP 400mm f/4 LD-IF.
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The Tamron 400mm 65B features 2 Low Dispersion elements to reduce flare, improve contrast and overall optical performance. It utilizes a large 112mm front filter which I have read may further improve sharpness but I have yet to test this. The 65B also utilizes the 43mm rear filters. In this day and age, we just leave the UV in and use filters in post.
Performance
Here is the sad part. The lens I got was in great condition. However, and it is a big however, the focus is not smooth. For some reason the action is coarse and stiff. I am hoping it is only the lubricant stiffening or something not involving a need to get parts. Because that will be nearly impossibly since this lens is relatively rare and has been out of production since 1995. Fortunately the seller (eBay) has offered to help with getting the lens serviced since this issue was not disclosed in the auction. Hopefully this beautiful piece of glass can be salvaged! I will have more on the performance soon!
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These vintage ads can be found on the Adaptall-2.com website found in the links/resources section below. I love these!
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Links/Resources
Adaptall-2 - This is a great resource for all Tamron adaptall products. They even have some of the original ads. I have requested permission for use of these ads for some time and haven't heard anything back. They are original Tamron ads (not original content of this adaptall site, who is not officially affiliated with Tamron).
Adaptall-2 Page on Tamron SP 400mm f/4 LD-IF