Recommended TC for Tamron 70-200 DI UC VSD F2.8

I am quite excited I pulled the trigger and decided to make some changes to my lens lineup and invest in a more versatile 2.8 lens.

I couldn't justify choosing the Canon II over this beast of a lens at literally 45% of the cost.

 

My Tamron should arrive tomorrow!!! I am tempted to do some bird and moon photography as an addition so I am thinking a TC is a nice small and relatively affordable addition to the lens.

 

I have a 6D with its very basic AF. I do want to invest in a nice Teleconverter.

 

My two questions would be;

 

1) 1.4X Vs 2X; read mixed reviews many said 2x on the tamron isn't good slow af; and quoted less than excellent performance of the tamron @ 200mm as a reason. Others said not an issue and they gave a rough rule of thumb that if the 1.4X lowers peripheral image sharpness by 10% then the 2x will only lower it by 20%. I am tempted to get the 2x obviously. I will probably borrow my sisters APS-C sized Canon for even extra reach.

Add to that many said TC lowers quality so much so your better off using 1x lower F-Stop when using TC. It's all mixed comments I read on older forums hence I thought I would ask here hoping I may get real world fellow photographers experience on this forum.

 

2) Kenko Vs Tamron Vs others; does it matter?

 

Thanks heaps

I was having a hard time looking the Tamron 70-200 DI UC VSD F2.8 up. I have the Tamron 70-200 DI VC VSD F2.8 and use it with a Sigma APO Teleconverter x1.4 EX DG.

It works OK for me. I imagine whichever teleconverter you choose will work okay. I own both the Canon 6D and a 5D MK IV, so I ran off some test shots with my Tamron 70-200 F/2.8 at various zooms and F-Stops to give you an idea. Keep in mind these have been reduced 2200 pixel width and you will need to click on each photo to view large. These images were shot using a tripod and VC was turned off.

As far as performance, I see a maybe a little performance drop in speed of focusing, hard to tell, been so used to using the 5D Mark IV and this was the 6D, this may be due to the added F-Stop reducing light into the camera. I think that is to be expected. The lens without a teleconverter is passing more light. But I can't tell you if the Canon would perform better than a third party Teleconverter. I thought the Tamron performed well using center point (Cross Type) focuswith the 6D. Edited March 6, 2018 by Mark Keefer

Wow and Thanks for your dedicated reply Mark.

 

I am very impressed with the 1.4x TC images you posted and I decided to do a shotgun approach and get the 2x teleconverter first. I've just ordered the kenko 2x one and I will see how I like it; If I don't like it I will get your exact same tele-converter as I am pretty happy with these results.

 

Thanks for your input; much appreciated.

Wow and Thanks for your dedicated reply Mark.

 

I am very impressed with the 1.4x TC images you posted and I decided to do a shotgun approach and get the 2x teleconverter first. I've just ordered the kenko 2x one and I will see how I like it; If I don't like it I will get your exact same tele-converter as I am pretty happy with these results.

 

Thanks for your input; much appreciated.

 

Thanks,

 

I hope the Kenko works well. The 2x will give you a little more reach. I got a good price on the Sigma 1.4x buying used at a camera shop. Post some shots after you get it and give us a review.

 

I should pick up a 2x one of these days. For me, It's like getting 3 new lenses, lol.

I saw Kenko has a 3x teleconverter. I had no idea they made them in 3x. Lol

LINK

I wonder how it would work with my 5D MK IV and my Sigma 150-600mm becoming a 450-1800mm. That would be a high F-stop at 1800mm but on a bright snowy day or viewing caters on the full moon, it might be interesting.

I picked up a used but good SIgma 2x Teleconverter, actually tried 2 of them, one older which did not work well, and then the newer version with coatings optimized for digital, I am underwhelmed. On the Tamron 70-200 autofocus works well between 70-175mm At 200mm the camera seems to have a hard time locking focus and this is with my 5D Mark IV. I tried the 2x TC with my Sigma 150-600mm and autofocus doesn't appear to even try so I will be using manual on that and give it another test tomorrow in bright daylight. At worst, I may be able to use it with a tripod for some moon photography. The performance does not compare to the 1.4x.

I just did some testing with the Canon 6D and the Sigma APO Teleconverter 2x EX DG.

I have found going into Live View and use Live View focusing and the 6D and the 5D MK IV nail focus instantly every time.

The Live View focusing with this 2x teleconverter is really good, so maybe someone else wants to try this if they are finding hard to lock focusing issues with a teleconverter.

 

So these tests were done with the 6D, this time handheld and VC on. The color might vary from x1.4 test above because of Lightroom settings I used, also no noise correction or sharpening was used.

Thanks for these detailed tests Mark!

 

It's funny you received a 2x TC and tested/posted the test results even before I got my Kenko 2x; I am still waiting.

 

I'm seeing these on my phone and I am impressed.

 

Now I won't be as objective as you are but I'm planning to post say 5 photos of nature I liked from my tamron 70-200 used on my 6D and on my sisters Eos rebel model (not sure of the name).

 

Then I plan to post my 5 favourite photos of the same setup but using the teleconverter.

 

But so far I am thrilled by my tamron lens that 70-200 F2.8 destroyed my F4 canon which I will sell soon and really made any portrait work for my canon 100 macro obsolete so that's going on sale too. I am very impressed and count myself lucky as mine is tack sharp focus and I kind of gambled by buying it grey import from Hong Kong for about $750 USD brand new.

 

I do have much firmer belief in DXO ratings now.

I have two really good camera shops near me, both authorized Canon dealers and both buy and sell used gear.

 

Ii think image quality is OKay. Just auto-focus through viewfinder suffers with the Tamron and the 2x.

 

I can see why people didn't like the 2x, through viewfinder focusing is not as good as 1.4x I also found the 2x works better in bright sunlight. But as I said above, if you go into liveview and focus it seems to lock focus better. When using the 1.4 x I really encounter no problems.

 

Interesting on my 5D Mark IV and the 2x I can focus in liveview, but through viewfinder focus pressing the front shutter button, using my Sigma 150-600mm the lens does not even try to focus. I believe this can be fixed if I do a camera firmware update. My 5D MK IV still has original firmware and there have been updates released, one is supposed to address an issue where the camera will not focus with some lenses when pressing the shutter button.

 

The problem does not happen with just the Sigma lens or using it with the 1.4x just the 2x. So I will give an update to my findings when I get a chance to update the camera firmware.

 

As I have read before, Canon makes sure their camera bodies work with their lenses, they make no guarentee the will work with third party lenses and accessories.

So I will admit, you probably can't go wrong sticking with Canon gear on Canon bodies. But Tamron and Sigma do firmware updates on their lenses too. Not sure if the Teleconverter has firmware.

Edited March 12, 2018 by Mark Keefer

using my Sigma 150-600mm the lens does not even try to focus. I believe this can be fixed if I do a camera firmware update. My 5D MK IV still has original firmware and there have been updates released, one is supposed to address an issue where the camera will not focus with some lenses when pressing the shutter button.

 

Just an update for anyone interested:

 

I just updated my 5D MK IV from firmware 1.01 to 1.04, the Sigma 150-600 C attached to the camera with the Sigma APO Teleconverter 2x EX DG can focus with LiveView, but still does not try to focus viewing through viewfinder using the front shutter button.

It's funny you received a 2x TC and tested/posted the test results even before I got my Kenko 2x; I am still waiting.

 

You still don't have it yet? It's been a week at least. :eek: Where are you? Is it being delivered by rickshaw? lol. I am looking forward to hearing your review and see your results. :)

As well as I know, Kenko makes the Tamron TCs.

 

The Nikon mount Kenko 2x that I have, has 2x reduction on the mechanical autofocus.

The 2x converter also doubles the rate of change of the focus signal.

 

But when used with lenses with a built-in motor, it doesn't slow them down.

Even more, with smaller aperture lenses, the autofocus signal is already small.

 

Used with an f/2.8 lens, it might AF, but it doesn't do so well with f/4.5 lenses.

Manual focus, it does work.

 

With a 1.4x converted, AF usually works on my lenses.

 

Actually, those tests were done on a D200. I now have a D700, but haven't tried them.

 

I also have a Vivitar 500mm mirror lens, and have used with with TCs.

Hi Mark,

I am back! So I received the Kenko 2x on Monda finally.

 

Most of the week it was cloudy here in Sydney, but when there was some daylight I managed to go to the same local Japanese Gardens and shoot the same subjects namely any bird/animals I see.

 

To make use of the long range I used my sisters Eos 700D; Kenko 2x and the Tamron 70-200 lens.

I then picked a few other shots using the same camera and lens but without the Kenko TC.

 

I was disheartened by the TC and did not shoot much; to it's disadvantage in this very rough comparison.

 

I know without the TC; most of my shots were ISO 100

With the TC; most were ISO 400-800

But despite this the images from the Kenko; not focused well despite aperture 1/400; no sharpness whatsoever and colour is hideous.

I will keep for now and try moon photography.

 

What I didn't realise is the lens without the TC is F2.8; with the TC it's F5.6; but you need to stop one more stop to get this ugly image quality even haha so that's literally 12.5% as much light as the original setup.

 

I posted 4 images from the Kenko TC and 5 without it. No need to say which is which!!!

 

Thanks Mark and Glen, and I hope some body uses this thread to make an informed purchase decision lol

 

 

 

H .JM,

A few sharp ones, some not so much. Sounds like a little disappointing first day out. I am not surprised the nailed focus numbers dropped. I am not sure how good the focusing system on a Rebel camera is compared to a 6D or 5D MK IV. Also Canon APS-C cameras are already a 1.6x sort of, so with the 2x TC sharpness may seem a little softer. I had heard the TC and APS-C combo are not the best match because of the 1.6x, it is like stacking two TCs. Not sure if it is that big of a deal, I recently sold my last APS-C the 7D so I have never tried it with the 2x TC but it seemed to well with my1.4x TC.

 

Try using the TC with the 6D, and if auto focus does not work well through the view finder, try it with Live View turned on to see if AF does not improve. For me, it really improved the AF. Also try the various AF modes to see how performance is.

 

The worst case, you may have to manual focus. A good test would be setting the rig up on a tripod to rule out camera shake and manual focus in Live View, if you just want to test how sharp the lens and TC are at best. Try some tripod mount manual focus moon shots might be fun. This sounded like only the first day out, so keep at it it and see if trying different things and with more practice your images with the TC will improve.

 

Good luck and let us know and see results.

I

went out today and did a few bird and waterfowl shots using the SIGMA 150-600 C with the SIGMA 2x Tele Converter mounted on the Canon 5D MK IV.

These have been reduced in size to post here, clicking on images will enlarge them somewhat but the images have not been cropped.

 

I used Live View autofocusing and was achieving about a 9 out of 10 keeper rate, most of the mess ups were my fault.

 

 

 

 

Edited March 17, 2018 by Mark Keefer

There are two versions of the Kenko (and Tamron) converters: MC4 and MC7, with 4 and 7 lens elements, respectively.

 

With an f/2.8 lens, AF is supposed to work, but maybe not. As I noted above, the 2x doubles the focus change rate, as seen by the AF system.

The feedback loop might not be stable at that rate. I have seen with f/4.5 lenses and TC for the AF to stop away from the focus point.

 

If the image isn't properly focused, then it won't look sharp to you, but it isn't the TC's fault.

 

Also, your depth of field might be very short. You should probably test lens sharpness with a flat target, such that DoF doesn't contribute.

 

Way too often, I find that AF focused on something different than I wanted.

Thanks again Glen and Mark;

Yes a lot of it is the Photographer; that's why Mark's latest photos are just amazing!

Now I retested with the 6D; using both viewfinder and liveview; both were good.

The keeper rate is definitely lower using the TC but on the positive side definitely better focus and sharper now compared to the 700D.

I find without the TC I often get many shots 100% focus where I want it; thus far with the TC unless I am using on the 70mm end of the lens; its rare for me to nail the focus right.

 

From a quick 15 mins shoot; I have these 3 shots to share.

 

.

Thanks Guys,

I think the TC also reduces your depth of field by half, assuming everything else is the same.

 

This would show up if you compare a cropped without TC against non-cropped with.

 

Definitely a TC reduces image quality, but, for a reasonable quality TC, it should mostly not be noticed at screen resolution.