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08-10-2009, 04:42 PM   #31
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QuoteOriginally posted by shane33 Quote
i use the sigma 1.4x on the Tamron 70-200 it works ok no dramas just the usual af hunt but it does work
Shane, are you sure you haven't made a typing error??? Because my Sigma 1.4 teleconverter doesn't even fit my Tamron....doesn't even come close!!!...???

08-10-2009, 07:20 PM   #32
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sorry about the shitty pic was to lazy to get out other camera this is diff to other tc disscussed but it works for me

08-15-2009, 11:15 PM   #33
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I wish i had the cash for one of these.
I have a Tammy x1.4 TC to go with as well.

Jackbullet ... got more shots of the FPV on the previous page????
08-16-2009, 03:45 AM   #34
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QuoteOriginally posted by Mechan1k Quote
I wish i had the cash for one of these.
I have a Tammy x1.4 TC to go with as well.

Jackbullet ... got more shots of the FPV on the previous page????

Just this one...

Attached Images
 
08-16-2009, 03:24 PM   #35
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do you guys think this lens of mine is good at focas been looking at a few shots heres one straight outa the camera and i was 200 mteres away at 122mm what do you guys think

Flickr: More detail about IMGP1482
09-07-2009, 05:10 AM   #36
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I still feel my images are a little soft at f2.8:

here is one i took this morning, 130mm f2.8



Also i did a test with and without my Kenko Pro1D UV filter i bought off ebay,, interesting results, both at 200mm f.28


With





Without



(click for larger image)

What do you guys think?
09-07-2009, 09:57 AM   #37
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130-135mm is this lens weakest focal length. I'd lose the filter
09-07-2009, 01:58 PM   #38
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The Pro1D filters shouldn't affect your results all that much, but yes, it's been documented that 135mm is the Tammy's weak point. So shooting wide open and at MFD there will show the lens's absolute weakest point - I guess if you really want to shoot up close like that a dedicated macro would be better...

Although happyant, the snake's head on the left does appear in decently good focus on that crop.

09-07-2009, 10:30 PM   #39
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Kenko Pro1D UV filter

thats the same filter i have on my tammy i might try it without it
09-27-2009, 02:04 AM   #40
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Now to go on with the saga of this lens - I have gone for another with B&H, which has turned out to have the same problem arising at just about the same time as the first one I bought from them.

Just awaiting advice as to whether I can have this lens repaired this time rather than just returned...
10-08-2009, 11:57 PM   #41
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QuoteOriginally posted by jackbullet Quote
Shane, are you sure you haven't made a typing error??? Because my Sigma 1.4 teleconverter doesn't even fit my Tamron....doesn't even come close!!!...???
By "doesn't fit" do you mean that the rear element of the Tamron would impact with the front element of the Sigma TC?

Looking at the photos from the DPReview review of the Tamron 70-200, it looks like the rear element is slightly recessed from the mount. However, their review sample was an EF mount (Canon EOS), which has a shorter registration distance than PK (44.0mm vs. 45.46mm). So in PK mount the rear element of the Tamron may in fact be flush with or go beyond the mount. If so, then it may not be possible to use the Sigma 1.4x TC. Could owners of the Tamron confirm if the rear element is recessed? By the way, we're only dealing with a difference of 1.46mm here.

I'd be very interested in knowing this myself, as I just picked up this converter and am currently deciding between the Sigma and Tamron 70-200 f2.8 zooms.

By the way, the Sigma TC works fine with my FA*200 (the rear element on this lens is *very* recessed), however it does not report the adjusted focal length to the body - my K20D still thinks it's 200mm. Though the SR is not optimal, it still helps.
10-09-2009, 12:05 AM   #42
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QuoteOriginally posted by raider Quote
Hi Ash. I don't quite understand when u say the Sigma TC will only work with the older sigma 70-200 without HSM. The Tamron 70-200 has no HSM and is a screw driven lens. Won't this work with the sigma TC or the sigma TC has different contacts and such which prevent the Tamron from being recognized?

Yes. I quite like my Tamron 70-200 but it is a huge lens to carry around. That is the only weakness I would say.
The Sigma 1.4x APO EX TC lacks the "power zoom" contacts required for Sigma HSM and Pentax SDM. However, if you're using it with a lens with body-driven (screwdriver) AF, then focus should be fine.

However, there is also a physical limitation with this TC - since the front element of the TC is flush with the mount, it can only be used with lenses that have a recessed rear element. I'm not sure if the Tamron 70-200 is compatible, and we seem to be getting conflicting answers from owners here. Hopefully we'll be able to get this cleared up soon.

And as I just mentioned, this TC also does not adjust the focal length that's reported to the body - it simply passes thru the focal length that the lens reports. So your SR will not be optimal (although it will still help).
10-09-2009, 01:29 AM   #43
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QuoteOriginally posted by Ash Quote
You're right Andi, and I haven't posted 100% crops - a little lazy at the moment, or maybe just exhausted...

I'm just keen to know, from anyone who may know, under what conditions would such a lens produce a hazy image when used wide open?
While I don't own this lens, and I also am unable to view the photos you linked to, I can offer some general comments and ideas which may help.

Firstly, a slight misfocus can often result in a "hazy" appearance. Have you checked to see if this lens is BF/FF with your body? Also, it could well be that the AF unit is simply not precise enough for the thin DOF at 200mm and f2.8. I have found that AF is often an "approximation", and to be absolutely certain I switch to MF. However, as you know it's hard to MF with the stock screen, but this is where LiveView (magnified view) can help, even with the blocky pixels (hint: look for contrast changes).

Also, what you're observing could be due to lens flare. In a long zoom such as this with close to 20 elements, there is a greater chance that flare/reflections will take their toll. You could try using a more "aggressive" lens hood.

Finally, what are you comparing these to? In this age of digital it's so easy for us to make comparisons - perhaps we are simply expecting too much of these long zooms?
10-10-2009, 04:56 AM   #44
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QuoteOriginally posted by photogerald Quote
While I don't own this lens, and I also am unable to view the photos you linked to, I can offer some general comments and ideas which may help.

Firstly, a slight misfocus can often result in a "hazy" appearance. Have you checked to see if this lens is BF/FF with your body? Also, it could well be that the AF unit is simply not precise enough for the thin DOF at 200mm and f2.8. I have found that AF is often an "approximation", and to be absolutely certain I switch to MF. However, as you know it's hard to MF with the stock screen, but this is where LiveView (magnified view) can help, even with the blocky pixels (hint: look for contrast changes).

Also, what you're observing could be due to lens flare. In a long zoom such as this with close to 20 elements, there is a greater chance that flare/reflections will take their toll. You could try using a more "aggressive" lens hood.

Finally, what are you comparing these to? In this age of digital it's so easy for us to make comparisons - perhaps we are simply expecting too much of these long zooms?
Focusing was checked prior to me testing - all was well.
Real life photos wide open at 200mm would clearly make focusing difficult, but even in my magazine/newspaper tests of this lens, wide open only created this haze when focusing near minimum focusing distance. But no flare - none of my shots where anywhere near shooting into the sun/light source.

This also occurred with a Sigma 70-200 HSM I had for a brief while, but it was significantly more pronounced - but it also had sharpness issues, so I did send it back. I've compared the Tamron and Sigma in another thread, but comparisons are not necessary if it is clear the lens has obvious deficiencies.

Expecting too much? Not sure about that. Both manufacturers pride themselves on the fact that their 70-200s have near macro abilities... handy but clearly falls short for 'macro' work given the image softness.
10-11-2009, 11:06 PM   #45
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QuoteOriginally posted by Ash Quote
Focusing was checked prior to me testing - all was well.
Real life photos wide open at 200mm would clearly make focusing difficult, but even in my magazine/newspaper tests of this lens, wide open only created this haze when focusing near minimum focusing distance. But no flare - none of my shots where anywhere near shooting into the sun/light source.

This also occurred with a Sigma 70-200 HSM I had for a brief while, but it was significantly more pronounced - but it also had sharpness issues, so I did send it back. I've compared the Tamron and Sigma in another thread, but comparisons are not necessary if it is clear the lens has obvious deficiencies.

Expecting too much? Not sure about that. Both manufacturers pride themselves on the fact that their 70-200s have near macro abilities... handy but clearly falls short for 'macro' work given the image softness.
I think we have their respective marketing departments to thank for this...

So what's the final conclusion - design limitation or bad sample(s)?
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