sony 70-400 vs tamron 200-500

I have had what seems to be a very sharp tamron 200-500.  I just bot a sony 70-400 and I am finding it NOT as sharp.  have done a few tests - hand held and the sony is consistently a little darker and a little less detailed.

see attached.  and these are probably the 2 closest shots.  which do you think is better?

will probably order another 70-400 to see if they are all like this.  check detail on roof

sony

tamron

I don't think tests like this will tell you anything except your testing mechanics are faulty. I can take two shots in a row with the same lens and get results that are different. Both are great lenses and both take incredibly sharp photos. I personally prefer the 200-500 since it has 100 mm more reach, it is lighter, it costs less and it has less zoom magnification (2.5x for the Tammy and 6x for the Sony). I would stop worrying about testing them and just go use whichever one you like the best.

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My photos:
picasaweb.google.com/seilerbird

what do you mean by zoom magnification?   I took about 20 pictures and there was a difference in everyone favoring the tamron.  I expected better from the sony.

The difference I'm seeing appears to be more contrast and light (which can provide an "apparent" difference in sharpness). These comparisons have so many variables that we cannot possibly know: exposure is same but did the lighting conditions change? are they in-cam jpgs? if so what settings (was DRO used)? if RAW were the exact same processing parameters used?

...I read several reviews and researched these two prior to buying the 70-400 a few years ago; I commonly read that the Tammy has great sharpness when stopped down to f/8, so the biggest question in my mind (assuming all the above questions are neutralized) is what does the comparison look like at f/5.6? I rarely stop down the 70400G because I nearly always shoot it at 400mm and need the faster shutter obtained wide open, and there is ZERO sharpness loss wide open with the 70400G. The wide open comparisons are what made the Sony worth the extra price to me at the time, I'm really interested to see that comparison with the current production.

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- AlanS

Zoom magnification, i.e. how much effective zoom range. 18-55mm zoom is a 3x zoom magnification lens (18mm x 3 = 54mm, close enough). So 200-500mm=2.5x, etc. A very general theory on lens quality is the higher the zoom magnification of a lens, the lower the IQ (I'm not saying that applies to your case, I have no experience with the lenses in question).

Superzooms (often criticized for their perceived lack of IQ) like the 18-270, for example, are 15x zooms. Sacrifices are made to effectively cover such a range; hence all the hate you see lavished on them by purists (their practical advantages aside).

It does present an interesting question nonetheless; does a lens like the 200-500mm, with it's lower zoom magnification, have potential IQ advantages over a lens like the 70-400 with it's higher zoom magnification, over their shared ranges? It's hard to make a fair analysis without seeing full res images. At f8 it may be the sweet spot for that particular lens; are your findings similar across the various apertures?

Have you considered that the Sony may need ReCalibration?

Am re-looking at your images, looking at the patches of snow, I'm seeing distinctly larger areas of direct sunlight (and correspondingly smaller areas of shade) on the Tammy shot, which indicates significantly more light in that image -- yet both were shot at the same exposure.

Perhaps, taken 1 1/2 minutes apart, there was a shift in sun/clouds to account for the brighter Tammy shot? Am not seeing better sharpness so much as better lit exposure.

Also, at 300mm f/8 this is likely sweet spot for the Tammy -- I've never used it but have read that it is softer at the extremes and softer wide open... The apparent lighting difference may equalize things between these two lenses at the given FL and aperture (the Tammy's sweet spot) and I'd suspect the Sony will win out elsewhere ,when compared at the long or short end wide open. Would like to see the results of that comparison!

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- AlanS

I can't tell much from the shots displayed.  The Sony is underexposed relative to the Tamron and that can mask differences.  It is very difficult, handheld to get the lenses to focus on precisely the same point, especially if there is a slope (eg the roof) as the point of focus.  Also, a slight difference in aiming (and time) can alter the exposure).  We do not know whether the crop shown was centre or edge.  the difference in weight of the lenses could affect camera shake - better to use a decent tripod if you really want to judge the lenses and be confident.  you say the results were consistent - were they all at f7.1 and 300mm?  Both lenses should be respectably sharp at that aperture.   I can only say that my copy of the Sony is sharper than my Tamron and I reckon I can compensate for the slight loss in reach by cropping.  Of course the Sony goes to 70mm and the Tamron to 200mm.  There are substantial differences in price, weight, speed of focus, etc.  Actually my Tamron seems to take better pictures now - but that's because it's being used by my prospective son-in-law and he is a much better photographer than I am (LOL).

If you are happy with the Tamron and you do not need the wider zoom range of the Sony, keep the Tamron and save some money.  There will be specimen to specimen variation of any lens and you could have got a particularly good Tamron.  Enjoy it.

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Sandy

well I wanted a back up lens to the tamron for when we take long trips as I need a fairly long lens for bird and other photography and in case the tamron goes kapop   and could use the 70 end as well at times. Not easy to buy or rent sony lenses when traveling.  more availability of canikon stuff.

both at 5.6   the sony has more of a CA tendency as well.

I have taken some more pictures and tried to be more consistent and shot at 5.6 I think and f8 and I am still finding that the tamron is consistently better.  sony shoot a bit darker and tamron a bit lighter.    they are all handheld and shot a jpegs with no editing other than how the camera is set - which is the same for all. except maybe shutter speed.  aperature and iso the same.

shot at f8

If you want to compare lenses, you should be shooting at ISO 100 on a tripod. If one image is a bit darker, then make exposure the same in PP. It may be a good idea to shoot several copies of the same image with the same settings on each lens, refocusing between each and select the sharpest if there is any difference. I know from experience that it is easy to jump to conclusions doing this sort of thing without putting some effort into it.

I have a Tamron 200-500, which I rather like, but these images are not convincing me that it is better than the 70-400.

I have here a photo I took with my Sony a330, which is a 10 megapixel camera and the Tamron 200-500. I have cropped it pretty severely so it is really only about a 5 megapixel image. The image was taken hand held. It was taken at a slow shutter speed of 1/320th of a second. The rule for telephoto lenses is not to use a shutter speed slower than the focal length of the lens. In other words for a 500 mm lens you should not use anything less than 1/500th of a second. But the Sony IS gives me several more stops so I can go slower than 1/500th. I shot this at the extreme range of the lens, 500mm, which is always the "softest" focal length of the lens. This lens is sharpest at around 300 to 350 mm. I used an aperture of f/6.3, which is wide open and wide open is always the softest aperture of any lens. And it is using ISO 400 which is not nearly as sharp as ISO 100. So with everything going against it this should not be a sharp image at all.





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My photos:
picasaweb.google.com/seilerbird

Am honestly not seeing any difference in sharpness; what puzzles me is the darker image with the Sony lens with the same exposure, and since these are in-cam processed JPG am thinking it may be variations in the way the camera is processing the files from the two lenses (?). And I haven't seen any of your samples taken at the long end.

Most folks I've talked to that are interested in purchasing a 400 or 500mm zoom are mainly wanting it for the telephoto end and the 90%+ shooting they would do at the long end. Every comparison I've seen between these two lenses at the long end concludes that the Tammy's softer wide-open 500mm images provide no advantage to cropping the Sony's sharper 400mm images to the same apparent FL. Just curious if you've made that comparison (wide open)? Am really interested in the comparison at that extreme, as I really see no sharpness difference in your samples. Can't explain the darker/lighter -- if it were me I'd shoot controlled RAW comparisons.

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- AlanS

Hi,

first I'd like to ask you a question whether your test shots were taken off a tripod?

If not, I'd say the exposure times in both sets with 1/250s in the first and 1/160s in the second would be a stretch towards too long exposure times for hand held shooting with such large and heavy lenses - particulary when you want to test and compare their optical performance. You're shooting with a A580 which has an OVF - and this means a mirror moving. This could have added vibration. Repeating, if you want to compare the optical performance of lenses it makes only sense when you avoid everything in the shooting process which has a great influence on the result - such as shake. Still considering that you took the test shots handheld, your results could be indicative only in a sense that you may be able to hold the Tamron steadier than the Sony - which may be of course the case due to their difference in weight.

For handheld shooting with a long tele (zoom) I can repeat only the hint to go for shutterspeeds of round 1/(2 x FL)s which means about half of the exposure time which was known from film times. Longer times may work but today's high MP sensors provide such rich details (since supported also by the lens mounted) that even slight camera shake and/or focussing errors get noticeable.

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Cheers, Michael Fritzen

I retested today (cloudy) with a different camera- the sony A700 and there is almost no difference between the lenses.  Or rather the difference is not favoring the tamron. Sometimes one lens is slightly sharper and sometimes the other lens is.

my original tests were on the sony 580.  COuld this have to do with the diff. in mexapixels in each camera?????  Or what????  even though the diff might not be apparent in my samples it is at my end with the 580 but not with the 700 camera.

Agree that handholding can make a difference.  and I do shake a bit more with the sony 70-400.

will try them on a tripod eventually.   no point in trying them in raw as someone suggested as I never shoot raw.

thanks for any thoughts.

One thing I'm seeing with your tests shots is that they're usually below the focal length/1 rule. Even with IS its possible to get motion blur at slower shutter speeds with lenses this long.

On aps-c you need to do focal length / 1 * 1.5 to account for the crop factor.

So the Sony 70-400mm at 400mm should be shot at a min of 1/600th

The Tamron at 500mm should be shot at a min of 1/750th

Anything less than this and there is a good chance that motion blur is going to affect your results with either lens. Now, I'm not saying its impossible to get sharp photos at shutter speeds lower than this, just that for testing purposes you should try to remove all other factors.

I've used the Tam 200-500mm and its an excellent lens, haven't used the Sony.

You should also test at 400mm and 500mm, IE: the main reason to own either of these lenses. The Tamron may be sharper at 200mm and 300mm, but the Sony may be sharper at 400mm, from what I remember the Tamron isn't at its best at 500mm, what I've commonly read is that the Sony is so good at 400mm that you can crop and negate the longer focal length of the Tamron, but again I've never used the Sony so  I have no idea if that is accurate.

Two more points to consider: 1) Neither the A580 or the A700 provide MFA. Prior to go FF in 2010 with the A850 I had two A700. And I bought the 70-400 roughly 1 year before going FF. So the A850 was the first cam I had with MFA and it made a difference. Now the last A700 has gone for an A99 so I continue now FF only and I wouldn't consider anymore a cam w/o MFA. Simply put, such terrifc resolution of the lenses and the high MP count of the sensors need to be adjusted to use the format / MP count at their best. 2) The increase in MP does make a difference when it comes to visibilty of lacking sharpness due to camera shake (too slow exposure times). I'm not sure whether this is true for A700 to A580 since I'm not aware about the MP count of the latter. But the reasoning is simple as one needs to imagine only the fact that the same (slight) shake whose projection might have covered one (fatter) pixel row on a lower res sensor, may cover now two or more pixel rows. Since many pictures are evaluated for sharpness/resolution at 100% pixel view it's clear that a detail, now spreaded over 2 pixel rows, looks / is "less sharp" / looks more blurred than before with the lower pixel sensor. Add to this that if the lens is able to provide detail for each of the pixel rows of the higher MP sensor, than potentially resolution power increases - but it needs more stability to warrant that this detail isn't spread. For the 36MP Nikon's as well as for even higher MP MF sensors the steadiness is a real problem for making use of the full resolution power of such sensors.

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Cheers, Michael Fritzen

What is MFA?

MFA=Micro Focus Adjustment

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Cheers, Michael Fritzen

As I asked higher up...

Have you considered having the 70-400 recalibrated.  They'll do it under warranty, and very very often it makes immense difference in the Lenses IQ.