Unsharp photos at 840mm using 1.4x teleconverter

[terrib]

Oh and in my long explanation I forgot a most important point. The AF was only consistent below f8. At f8 it failed more than it worked. So no, I don't think I'm being unfair to Tamron.

[rpcrowe]

Terri... You mentioned that, "The head is a gimbal style Jobu Jr rated at 10lb (my camera lens combo is less than 8) It was locked down in all directions."

I have very little faith in the load capacity published by any tripod or head manufacturer. They tend to over-estimate the capacity of their tripods and heads - for advertising purposes.

When I look at a capacity of any tripod or head combination, I will usually make my MINIMUM choice in one that is advertised to have 2x OR GREATER capacity than the load I expect to have it support. I suspect that one of your problems might be that your tripod and head combination is not up to the load that you are placing in it.

Perhaps you could rent a very sturdy (read: very heavy) tripod and head and then try your lens + TC using that tripod/head...

My Giottos MT-8180 tripod has heavy weight relatively large diameter graphite legs. It is no longer sold and I don't remember the advertised weight capacity but, would guess that it is well in excess of 20-pounds or so. My Giottos MH-1300 ball head is also large and I would guess that it matches the capacity of the leg set.

I am going to experiment with an older (Mark-1) Canon 1.4x TC and my 100-400mm f/4.5-5.6L IS II lens on my 7D Mark II camera. I will use this with my Giottos MT-8180 Tripod and MH-1300 head and also with my Manfrotto Gimbal that tripod I am just waiting for some clear weather. We are luckily getting an unusual amount of rain in the San Diego area. Good for everything but, long lens testing.

I did shoot a shot today (my first with the 7D2 and 100-400L II + 1.4x TC combination)

Photos at 896mm using 1.4x TC

I also have an old Burns and Sawyer tripod that I think might very well support a Volkswagen auto. It is about as heavy as the Volkswagen, anyway. I once used this to support my 16mm motion picture cameras (Arriflex and Bell and Howell Filmo). I will try this tripod if I have problems with the Giottos rig. Of curse, the Mark-I TC is not the best TC in the Canon lineup for long lens digital photography.

[William W]

. . . I hope you don't think it was a waste of time to make your responses. I don't because I think it was still a good discussion with lots of information people can use to do their own tests in similar situations. Thank you for your time!

The conversation was useful for me. Thanks for posting your debrief.

As an holistic comment, I understand that your expectations were not met and I do think that Tamron has a case to answer: this is not the first and will not be the last of this type of situation. Sigma has a few similar situations, in their history. Advertising and Marketing Departments often seem devoid of simple and objective engineering detail. That’s not limited to third party companies – Canon’s Advertising can at times seem “misleading” at worst or “confusing” at best.

On the other hand: Canon does not absolutely guarantee that the 7DMkII will Auto Focus at F/8 in all situations - in fact it doesn't make that guarantee at F/2.8 either – I think phrases such as “capable of high precision Auto Focus” are used in the Technical Specification Sheets. (That’s neither arguing nor implying that your original testing of the first 1.4 extender was done in poor light or flawed in ay other manner).

Also note that Canon (and Nikon) are pro-active in advertising that neither company warrants any performance or technical specifications describing their cameras when those cameras are used any third party adaption, be it battery, lens, extender, extension tube, filter . . . etc

I think one take away of this conversation is that: if one is to have a reasonable chance to attain precision technical performance in extreme situations (assuming that we concur that the use of x1.4 on a 150~600 F/5~ F/6.3 zoom i.e. Effective Maximum Aperture when lens at 600mm is F/9 . . . is an extreme situation) then, for us to have the best advantage of achieving those goals we should use the proprietary tools which were specifically designed for that task: the EF 600 F/4 IS USM (or MkII) and the Extender EF 1.4 MkIII. There are two prongs to that, firstly the lens speed – and secondly the single manufacture who is making the warrantee of performance for all the three parts of the system: lens; tele-converter and camera.


That is NOT a suggestion that you (or anyone) should only buy Canon gear – nor is it implying ‘Canon Snobbery’: but it is an attempt to provide balance to the annoyance directed to Tamron: I understand that you are upset or annoyed, but equally I do think that the expectations (even if those were somewhat flawed expectations based upon “advertising extensions”) should serve as a general indication that, when we want high level performance at the pointy end of any Camera equipment – then that is exactly what and why lenses like the 600/4 IS L are designed and manufactured.

Obviously these high grade and highly sophisticated lenses come at an extreme (comparative) cost – to, for example the 150~600 Tamron: and in that regard, my feeling is that you (Terri) tried a set of options within a budget and it seems you are very happy with your Tamron Lens – but you didn’t get everything that you expected out of the extender. I don’t think all that much was lost – you might be a bit disappointed, but you didn’t lose much except a bit of time and effort . . . but during that time I think that you gained a wealth of experience.

WW

[terrib]

William, I agree.

Thanks for all your time in this discussion.

[Saorsa]

Oh and in my long explanation I forgot a most important point. The AF was only consistent below f8. At f8 it failed more than it worked. So no, I don't think I'm being unfair to Tamron.

Most cameras do not AF well at f8. Some will try but there is a lot of dependency on subject if they are to succeed.

I have a TC-14 and TC-17 with min Nikons. Sometimes they focus sometime not. Below f8 they work well, at f8 I start getting failures. In bright light witih a decent subject they work well.

[DanK]

Also, if I am not mistaken, 64 of the 65 AF points in the 7D II work only until f/5.6. Only the center point works at f/8.


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[Tronhard]

When I was seeking to get a replacement for my Canon 100-400L Mk I, I had in mind that I would add an extender to it. I agonized over this for some time, pouring over the specs and capability charts for several manufacturers, and noted that most of the time one lost a fair degree of the features one wants in a DSLR - specifically IS, autofocus and some degree of auto exposure (e.g. AP). Because capability is a function of the combination of the lens, extender AND the camera body it is extremely hard for a third party lens maker to cover multiple brands and models and get the best out of them all. That conclusion led to stick with the Canon gear, but even then there were lots of "Ifs Ands and Buts" in the Canon documentation - the compatibility list is extensive and very detailed!

I finally settled on the Canon 100-400 L Mk II (an awesome lens!), the Canon 1.4x Mk III extender and the Canon 80D. From the specs this was the combination that was the most modern and was indicated by Canon as working most seamlessly together. The 7DII, which I also have, works with some limitation, but the 18 months difference between the two bodies is that period when the 1.4 Mk III extender came out, so it worked on a backward compatibility mode (so to speak) whereas the 80D design team presumably knew of the extender and the lens and could handle it well. Canon have made some strides in the technology of their bodies of late and I suspect the 7DII, while an excellent body, is slightly eclipsed by that.

I have taken images using the lens with extender on both bodies and have to admit the 80D seems to offer more capability for moving targets. Now, that said, I have also taken images of more static subjects with the 7DII and it has produced excellent results, but it has not had to focus track to do so. I might add I almost always use spot metering so the characteristic of centre focusing with the 7DII was no big issue for me.

[NorthernFocus]

I've completely stopped using TCs on zoom lenses. The one exception to that was the 70-200 f2.8 plus 1.4xTC effectively netting a 100-300 f4. But I sold that lens so now TCs are used solely on primes. There is no getting around the fact that AF works better the more contrast(i.e.more light) that it has to work with. We tend to forget the math/physics. Recall that shooting with a max aperture of f8 delivers half the light of a lens with max aperture of f5.6. And with zoom lenses the stated apertures are typically grossly optimistic versus the actual T-stop.

Even if the camera can tolerate it, using a TC or not is really a value judgement. In the case of a 1.4xTC one must consider whether being effectively 40 percent closer is worth having half the light. Not to mention any optical aberations due to the TC and potential image degredation introduced by technique at extreme focal lengths. With modern high rez sensors IQ may ultimately be better by cropping heavily than by using the TC.

[Tronhard]

I agree completely about needing the right amount light, but I will happily maintain that they do have their place when there IS sufficient light and you want the reach but not a super high f-stop. I tend to follow the summer between hemispheres so most of the time I have an abundance of light, in fact it can be downright embarrassing because I have to use too high an f-stop! UNDER SUNNY CONDITIONS I have achieved good results with the 1.4 on my 100-400 zoom.

Even if the camera can tolerate it, using a TC or not is really a value judgement. In the case of a 1.4xTC one must consider whether being effectively 40 percent closer is worth having half the light. Not to mention any optical aberations due to the TC and potential image degredation introduced by technique at extreme focal lengths. With modern high rez sensors IQ may ultimately be better by cropping heavily than by using the TC.

[rpcrowe]

Dan, commented, "Also, if I am not mistaken, 64 of the 65 AF points in the 7D II work only until f/5.6. Only the center point works at f/8. "

That is quite true and you are not mistaken...

My present conundrum is whether the 1.4x Mark III TC is sufficiently optically superior to the 1.4x Mark I TC to justify the additional cost (cost of the Mark II minus what I could expect to get from selling the Mark I).

I also have to work more with the Mark I on my 100-400mm f/4.5-5.6L IS II lens and my 7D Mark II camera. I also have to ascertain if I really need the extra focal length afforded by the 1.4x TC (of either version).

I suspect that an interim step might be renting the Mark III and comparing it head to head against the Mark I. That should not be too expensive...

I wonder if renting an 80D camera at the same time might not give me a chance to evaluate the lens and both TC versions on moving subjects...

[rpcrowe]

Every other lens I own is a Canon but the Tamron 150-600 is affordable for that focal length. This second generation lens is performing quite well. No problems with the lens. It's the teleconverter which I am exchanging. If the second one doesn't work, then it'll get returned for a refund. I'll still be happy with the lens. I believe the warranty is 6 years.

Your lens WITHOUT the TC on a 1.5 (ish) crop camera would give me just about the same focal length as my 100-400 with a 1.4x TC on my Canon 7Dii...

[Tronhard]

It all depends on what you are shooting and how you want to output the results, along with (as I say) the shooting conditions (particularly light intensity) that you will encounter.

[Tronhard]

Dan, commented, "I wonder if renting an 80D camera at the same time might not give me a chance to evaluate the lens and both TC versions on moving subjects...

I would absolutely encourage you to try the 80D with the Extender III and see how it works for you. If you can rent it, it will clarify a lot of issues I suspect.