[ryan.wadsworth]

Staff note: This post may contain affiliate links, which means Pentax Forums may earn a small commission if a visitor clicks through and makes a purchase. If you would like to support the forum directly, you may also make a donation here.

---

Hi.

At the moment I am looking to buy a zoom lens and I am currently looking at ether the Sigma 70-300mm GD macro lens or the Tamron 70-300mm Di LD lens, they both retail on amazon for around £99.00 they both claim to have macro focusing abilities.

I would like to know what one you think is better over all in terms of sharpness focus speed,, build quality ect.
I will be using the lens on a Pentax K5.


Thanks.



Links to both lenses

Sigma:

http://www.amazon.co.uk/Sigma-70-300mm-f4-5-6-Digital-Cameras/dp/B000B8T6E2/...+70+300+pentax


Tamron:

Tamron AF 70-300mm F/4-5.6 Di LD Macro 1:2 for Pentax: Amazon.co.uk: Camera & Photo

[TER-OR]

I can only comment on the Tamron 70-300 lens, which on my K5 exhibited a LOT of purple fringing - a variety of Chromatic Aberration. It was a decent lens on the K10, but just not on the K5. The DA 55-300 was my solution - you can get a used one for about $250 now.

[VisualDarkness]

I can only comment on the Tamron 70-300 lens, which on my K5 exhibited a LOT of purple fringing - a variety of Chromatic Aberration. It was a decent lens on the K10, but just not on the K5. The DA 55-300 was my solution - you can get a used one for about $250 now.

A lot is an understatement, it can magically paint any black and white clothing into bright purple. Also the image quality diminish quite quickly towards the close focus.

[DDoram]

I have had the Tamron 70-300 but not the Sigma version. I sold the Tamron and now have the Pentax 55-100 L version which appears to be sharper than the Tamron but not the close focussing ability.

Dale

[percy]

I had a Tamron 70-300, and for the price it's good value for money and a good starter lens - but the Pentax 55-300 is better and worth saving up for. Get the Tamron by all means, but maybe regard it as a stop gap until you can get the Pentax lens which will undoubtedly give better results.

[AldaCZ]

I can only comment on the Tamron 70-300 lens, which on my K5 exhibited a LOT of purple fringing - a variety of Chromatic Aberration. It was a decent lens on the K10, but just not on the K5. The DA 55-300 was my solution - you can get a used one for about $250 now.

I used an Nikon(on D60 or so) version and it had a lot of fringing.

[tibbitts]

I have the Tamron 70-300 LD Di and the Pentax 55-300DA, so I can only comment on those two alternatives. There are pros and cons:

1. The Tamron has macro mode, but only at 180-300mm. I've only found it useful at 180mm, whether due to motion issues or optical performance, but by my standards macro is pretty good at 180mm. On the other hand, the Pentax 55-300 works well with a Nikon 3T, and yes you can use a 52mm filter on either lens (even the 62mm Tamron) without incident on APS-C.

2. The Tamron has more PF at the longer focal lengths particularly. I haven't experimented enough with software to determine the degree to which the net results would be different. However in the majority of my pictures PF has not been an issue. If I was, for example, primarily photographing birds, PF might be a lot more significant to me, although certain it can/does sometimes show up in other photos.

3. I'm guessing sharpness would be pretty similar between perfect copies of these lenses, discounting the PF issues at long focal lengths. Having gone through 5 copies of the Pentax (DA and HD), I've yet to find that perfect copy to compare.

4. The extra 15mm on the low end of the Pentax is very, very useful, if you don't have another lens covering that range.

5. The Pentax is a more solid-feeling lens, although there's not a dramatic different.

6. The Pentax has quick shift and a non-rotating front filter mount, which are very valuable features.

Since the Sigma you're looking at isn't even the allegedly-APO version, based entirely on 2nd-hand reports I'd go with the Tamron in that comparison, unless maybe you're a bird person (or photograph similarly contrasty objects.) If you can find a non-defective 55-300, that would be my clear preference. But until you find one, the Tamron is a decent, if uninspiring, substitute.

The newer Tamron 70-300, while more expensive, might be preferable to any of the other lenses discussed, but of course Tamron seems to be committed to not producing any modern lenses for Pentax, so that's not an option.

If you get the Tamron, I wouldn't bother "upgrading" to the Pentax (obviously, since I have both and mostly use the Tamron, although I have a non-awful copy of the 55-300.). Instead if you must upgrade, consider one of the other (relatively few) choices: the 60-250 Pentax, or the old-design 70-200 Tamron.

[wsteffey]

I have two copies of the older Sigma 70-300 APO DG and use these lenses more than any others. Image quality is excellent for what they are. I have two because the auto focus function failed on both after minor bumps. A design fault no doubt. Oddly, after repair by Sigma both lenses work fine on my Kx, but not on my K100d. Don't know why.

[normhead]

Some Sigma 70-300 images...













My copy was good from 60-150, and good up to 300mm at close range, Pretty low IQ from 200-300mm at infinity or close to it. When I bought it with my *is 10 years ago it was the latest thing since sliced bread. These days, not so much, but still a great lens for the money.

[reeftool]

I bought my K10D in 2007 at a Ritz Camera store. It was a 2 lens kit with the DA 18-55 and a Sigma 70-300. (The DA 55-300 wasn't built yet) The Sigma has served me well. Most recently, I used it at motorcycle races on my K5. I did all my shooting from the top of the grandstand at 300mm and cropped the shots. Outdoors on bright sunny days, this lens does well. It needs to be stopped down to f/8 - f/11 for it's sharpest results. The macro range is in the 200-300mm end of the zoom and works very well. The Sigma 70-300 (non APO, which is what mine is) sells new for around $150.

[kharry2012]

I own both. Sigma is super sharp and has gotten me lots of compliments (even more than my FA 43!). It performs exceptionally well in harsh midday light. Colors can be a little muted. Tamron is also very sharp. Colors are warmer. And photos are a tad more dimensional. I intend to keep both. But if forced to sell one it would be the Tamron. Think of them as 70mm primes with zoom reach and macro capabilities when needed.

[ryan.wadsworth]

Thank you all for your comments! In the end I went with the Sigma and now for the sake of any once else looking to buy one I shall talk about my first impressions with it.

My first experience with the a sigma 70 - 300 was a few years ago when a friend had a Nikon mount one attached to a Fujifinpix s2 pro I remember the auto focus being very slow and quite loud it would aso hunt for a while, since getting my own one and mounting it on my K5 it handles much faster in terms of focusing and it also seems to be of better build quality, the nikon version had plastic mount where as my one is metal. I have yet to load any images taken with this new lens on to the computer but from the look of them on the camera screen they look to be fairly sharp and only light firing when shooting back lit subjects.

So far I am quite pleased with the lens and its focusing performance especially reading lots of reviews saying it would "painfully hunt for focus" If you are looking to buy a 70-300 and are on a budget then I would have no problem in recommending the Sigma. The physical build quality of the Sigma is also better than expected I had anticipated very cheep plastic that is remenicant of the milk tray box but it feels sturdy and robust.