Tamron developing 150-600mm VC USD lens

pknight wrote in post #16683250
Truly! It seems that we are fools for trying to make judgments based on anything we see online. This will save me a lot of time, not having to look at images from this (or any) lens any more.

The points about resampled images are accurate, of course, but the real question for me is whether, with normal post-processing (which I would do with any image that I actually planned to use for any purpose), the results are acceptable. The images I have seen from this lens suggest that this will seldom be a problem.

Yep. My point of comparison is the Sigma 50-500, which has worked great for me when I rented it. Some say the Tamron is slightly better than the 50-500, some say slightly worse, bit in either case the difference is small, so I know the Tamron will do what I need.

pknight wrote in post #16683250
The points about resampled images are accurate, of course, but the real question for me is whether, with normal post-processing (which I would do with any image that I actually planned to use for any purpose), the results are acceptable. The images I have seen from this lens suggest that this will seldom be a problem.

Yes, that is always a problem. A sample of 10 really good low-res images doesn't tell you much. A sample of 10 really good high-res images tells you there's potential - but you don't know if the AF is so flaky it took the guy 200 shots to get 10 decent ones. You also don't know if he's done lots of post processing on them to sharpen them up, so it can sometimes be difficult to judge the likelihood that (even a good copy of) a lens will do the job; until at least there are enough separate reviews to give you a decent idea of its capabilities. Life is rarely simple

lescrane wrote in post #16681669
like the review, don't like the nickname "Bigron"...just doesn't have the panache of Bigma.. Tamonster would be better imho

I like that, "Tamonster".

That's got to be the best nickname for the lens that I've heard of so far.

Roger

sploo wrote in post #16683288
Yes, that is always a problem. A sample of 10 really good low-res images doesn't tell you much. A sample of 10 really good high-res images tells you there's potential - but you don't know if the AF is so flaky it took the guy 200 shots to get 10 decent ones. You also don't know if he's done lots of post processing on them to sharpen them up, so it can sometimes be difficult to judge the likelihood that (even a good copy of) a lens will do the job; until at least there are enough separate reviews to give you a decent idea of its capabilities. Life is rarely simple

Most of the serious efforts to review this lens that I have seen, such as the one by the gentleman from India, indicate the extent to which the images have been processed. Typically it is minimal, and I can see no reason for these people to be dishonest about this. Nor do I think anyone but a Tamron employee would have a motive to not mention that (to use your hypothetical numbers) only 5% of their shots were sharp and in-focus. And what if the images have been processed to make them look their best? As I said, that is what I would intend to do myself, and so such images might indeed be good indicators of what I can expect to end up with.

Others have questioned AF, and these reviews also typically discuss this issue, as did the review in question from India. What I appreciated about his comments about AF for moving subjects was the common sense recognition of the inherent difficulties of focusing on a moving target at 600mm, regardless of the lens. This difficulty is even more pronounced on a crop camera, with the FOV of a 960mm FF lens. While I have some BIF shots taken with the 100-400 that I am very happy with, that lens also fails to obtain or maintain focus more often than I would like, usually because I can't keep the subject on-target. There is no reason to expect that a $1069 lens with a much narrower FOV is going to somehow perform this most difficult of focusing tasks with ease. Luckily, if I had this lens I could zoom out to 500 or 400 for such shots, and it would be much easier to obtain focus, I suspect.

The remaining question, in my mind, concerns the problems some report with AF failing to work at all on occasion. Some have discerned a pattern to this with certain bodies but not others, but there are counter-examples that question their conclusions. I'm really not sure what to make of this issue, so far.

pknight wrote in post #16683371
Most of the serious efforts to review this lens that I have seen, such as the one by the gentleman from India, indicate the extent to which the images have been processed. Typically it is minimal, and I can see no reason for these people to be dishonest about this. Nor do I think anyone but a Tamron employee would have a motive to not mention that (to use your hypothetical numbers) only 5% of their shots were sharp and in-focus. And what if the images have been processed to make them look their best? As I said, that is what I would intend to do myself, and so such images might indeed be good indicators of what I can expect to end up with.

Others have questioned AF, and these reviews also typically discuss this issue, as did the review in question from India. What I appreciated about his comments about AF for moving subjects was the common sense recognition of the inherent difficulties of focusing on a moving target at 600mm, regardless of the lens. This difficulty is even more pronounced on a crop camera, with the FOV of a 960mm FF lens. While I have some BIF shots taken with the 100-400 that I am very happy with, that lens also fails to obtain or maintain focus more often than I would like, usually because I can't keep the subject on-target. There is no reason to expect that a $1069 lens with a much narrower FOV is going to somehow perform this most difficult of focusing tasks with ease. Luckily, if I had this lens I could zoom out to 500 or 400 for such shots, and it would be much easier to obtain focus, I suspect.

The remaining question, in my mind, concerns the problems some report with AF failing to work at all on occasion. Some have discerned a pattern to this with certain bodies but not others, but there are counter-examples that question their conclusions. I'm really not sure what to make of this issue, so far.

Good questions raised in the last few posts. I know for me from the photos I've posted (Snowy Owl and Red Tail Hawk) I took a ton of photos of each and it was a complete toss up of which ones I could have put up because 99% of them I was happy with the focus and sharpness.

In case any one is interested my PP is limited to minor tweaks in levels/saturation etc and a final smart sharpen at 50% after re-sizing.

As far as BIF images go I still haven't had a chance to really put it through it's paces. The shots of the gull came out great, I've had some other series that didn't but I have the same thing happen with my 400L f/5.6 as well. I'm still learning things like should I have VC on with BIF's or not (no matter what the manual says) and as you said keeping the AF point on target with such a long lens. Even with the gull shots one of mine missed the center point and probably only stayed in AF because I had center + expansion turned on.

Nice discussion here.

pknight wrote in post #16683371
Most of the serious efforts to review this lens that I have seen, such as the one by the gentleman from India, indicate the extent to which the images have been processed. Typically it is minimal, and I can see no reason for these people to be dishonest about this.

Absolutely - I'm not suggesting anyone's trying to deceive; my point was that if you compared a shot from lens A and a shot from lens B, and they both looked similar (in terms of sharpness) but the shot from lens B was SOOC (as much as that can ever mean) and the shot from lens A had received significant post processing work you'd want to know (that it wasn't a strictly fair comparison). Obviously that would need original and post processed shots from both lenses, in order to make a judgement about the lens itself, and how well the shots take a bit of sharpening.

palmor wrote in post #16683415
Good questions raised in the last few posts. I know for me from the photos I've posted (Snowy Owl and Red Tail Hawk) I took a ton of photos of each and it was a complete toss up of which ones I could have put up because 99% of them I was happy with the focus and sharpness.

Your Snowy Owl photos are a major motivation for me to get this lens. We only have them here (Kansas) when they are driven far south by weather, which is almost never. However, I can find Great Horned Owls pretty easily, and hope to get comparable results if I get the 150-600.

can someone recommend an arca swiss mounting plate for the Tamron

am new to Arca Swiss heads. I bought a SIRUI monopod head and am using that qr plate which is 2.33 inches long

http://www.amazon.com …s-including/dp/B006JZ7QZ​C

the plate is a hair shorter than the tripod collar foot of the tammy;

I also bought an Acratech GV 2 ball head with no plate.

So, should the plate be a bit longer than the foot??

tx

btw, am liking the acratech. very smooth, have not used the gimball feature

Not happy w/the SIRUI. I bought it because I wanted something more robust than my Manfrotto swivel head, and wanted the fluid tilt back. However, the tension knob freezes..literally in cold temperatures and won't move.

I think the plate should be longer than a tripod collar foot unless you get good balance with a shorter plate already. But it is always good to have longer plate for future upgrade

tx tx

DXOMark has tested the Tamron 150-600mm

http://www.dxomark.com …lens-review-New-contender

5DMkiii summary
Against the Canon, the Tamron is, surprisingly, slightly sharper between the 150-300mm focal lengths, though there’s not much in it at 400mm – the Canon is sharper centrally though the Tamron has the slightly better uniformity across the field. However, the Canon has heavier vignetting at 400mm and noticeably more lateral chromatic aberration in the corners.

pknight wrote in post #16683567
Your Snowy Owl photos are a major motivation for me to get this lens. We only have them here (Kansas) when they are driven far south by weather, which is almost never. However, I can find Great Horned Owls pretty easily, and hope to get comparable results if I get the 150-600.

I hope you find some great horned owls as well! Love owl shots since they really are pretty rare (except for Snowy's around this area this year).

pknight wrote in post #16683371
The remaining question, in my mind, concerns the problems some report with AF failing to work at all on occasion. Some have discerned a pattern to this with certain bodies but not others, but there are counter-examples that question their conclusions. I'm really not sure what to make of this issue, so far.

I haven't seen any comments regarding what focal length these AI Servo issues are occurring at ? or maybe it's all of them.

Just got the lens the other day and while I haven't been able to any real AI Servo testing in the field with it, I did notice a consistent issue with the AF while testing in the back yard. Basically up to 425 mm worked pretty good but after that it's almost non existent in low light. I tried to focus on a brick wall that was in the shade and over 100 feet away. Up to 425mm no problem in One Shot as well as AI Servo. Go to 450+mm and I couldn't get a focus lock in either mode and I was on and off the focus button like crazy. Now while in AI Servo and the shutter pressed half way I moved from the brick wall to an area the sun was hitting and still no focus lock, I had to let off and repress to get focus. Camera is a 7D

I got my copy this week and finally tried it outside for awhile,Right now my only body is a T1i as my 60D is in the shop. So its big,seems well made but I think has focus issues at least with the body I am using,Will Not take a sharp pic at all at 5-600 mm no matter what setting I try and even on a tripod using a remote,Even using manual and live view it looks clear and good pointing at a subject but pics are All not good at all. But At 150 they look great even hand held in low light.

So it could be it does not like my T1i,,I Have used a 100-400 with this body without any issues and also the bigma so its a head scratch-er right now..Will have my Good body back in a few days but I have a bad feeling its a bad copy.