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06-23-2015, 06:20 AM   #1
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Not happy with my 17-50 Tamron for Canon

The short of a long story.

Up until Fall last year I had a Tamron 17-50 that I was very very happy with on my K30 until I dropped it in the Mediterranean Sea.
I didn't replace the lens until early this year when I acquired a Canon 1000d for astrophotography and realized I could get a Tam 17-50 for the Canon and have two cameras to shoot with for the those special occasions.

I've had the Tamron for a few months now and simply not happy with the IQ. It's just not as good as my old Pentax one.

I'm definitely going to sell it but have since look for replacements and for the money I'm not sure I can do better. The Canon 17-55 is too pricey for me.

I guess I need a pat on the shoulder and need to hear someone say just get another Tam 17-50 and maybe it will be better.

Feeling sorta bad all over again for drowning my Pentax Tam17-50,

John

06-23-2015, 06:31 AM   #2
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If you got the newer image stabilized/built in motor version, every test shows it is not as good as the old screw drive model without stabilization that they still sell for Pentax. Not as sharp, has more distortion, etc. They re-did the optical formula to fit all the extra stuff in the barrel and that is the price for it...

Why Canon for astrography anyway? I would think the smaller crop would make it harder for sky pictures. The 17mm of the Tamron in the Pentax, becomes over 18mm in the Canon. I guess the question is, why not just get the Pentax again?

Last edited by ChristianRock; 06-24-2015 at 10:45 AM.
06-23-2015, 06:32 AM   #3
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It is my impression from reading many relevant threads, that the Tamron 17-50mm has the least reliable auto-focus of any lens available for APS-C, across all brands. Even focus adjust won't always help.

My research showed the Sigma 17-50 is significantly sharper than the Tamron wide open, much better built and has silent and reliable AF. I bought one for my K-3 and I'm very impressed.
06-23-2015, 06:33 AM   #4
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MIne, that I bought for my wife a couple years ago, has completely stopped auto focussing accurately and is going to have to be sent in for alignment. We love the lens, but right now it's a pain in the derriere. We already have a Sigma 18-250 in for a similar issue. Meanwhile my 18-35 that is two years older than either of them, just keeps chugging along. I'm starting to sour a little on 3rd party solutions.

06-23-2015, 06:42 AM   #5
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Many thanks for your quick responses.

Canon is overwhelmingly popular for many reasons in astrophotography circles. I didn't mind going that way since I liked the idea of a well rated second DSLR that could double for day and night use.

I do not know how to tell how old this Tamron is. It's made in Japan and has serial number 139736. (It's a 17-50 LD XR D ii)

I'll take a look at the Sigmas for Canon and perhaps ask prospective sellers about just how good the IQ of their units are.

Thanks for you inputs!!
JOhn
06-23-2015, 07:06 AM   #6
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I used the Sigma 17-50 f2.8 and can confirm that the sigma doesn't have the focus issue (at least my sample doesn't ) and the IQ is great (comparable to primes) !
06-23-2015, 07:12 AM   #7
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From what I gather, Tamron has some quality issues. If you have a good copy of a lens, they're great. Perhaps this lens could be sent in for a service to make sure it's all well-aligned and calibrated to a standard? They also seem to have different grades of lenses sharing the same focal ranges, which makes things confusing.

06-23-2015, 07:36 AM   #8
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QuoteOriginally posted by TER-OR Quote
From what I gather, Tamron has some quality issues. If you have a good copy of a lens, they're great. Perhaps this lens could be sent in for a service to make sure it's all well-aligned and calibrated to a standard? They also seem to have different grades of lenses sharing the same focal ranges, which makes things confusing.
There are not grades of Tamron 17-50, but there are older and newer versions. Some say the old version, without image stabilization, is somewhat sharper than the new version with IS. Neither version is as sharp as a Sigma 17-50 wide open.
06-23-2015, 07:48 AM   #9
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QuoteOriginally posted by audiobomber Quote
There are not grades of Tamron 17-50, but there are older and newer versions. Some say the old version, without image stabilization, is somewhat sharper than the new version with IS. Neither version is as sharp as a Sigma 17-50 wide open.
Thanks, that may be what I was thinking of. I knew there were a couple iterations of that lens. It's a range I've considered occasionally.
06-23-2015, 10:18 PM   #10
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My copy of the 17-50 is just fine, Iksobarg - sharpness and AF. It's part of my two zoom setup along with the DA*50-135.

That's not to say there isn't sample variation, and that quality control isn't the same amongst all companies. Sorry to hear yours might not be great. :-(
06-24-2015, 10:51 AM   #11
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The XR version has the optical stabilization (according to my search) so that is the inferior version optically. Look for the older LD Di version.

I'd still get it for Pentax instead if I were you... the 1000D just isn't a good camera for low light shooting...
06-24-2015, 01:55 PM   #12
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QuoteOriginally posted by ChristianRock Quote
The XR version has the optical stabilization (according to my search) so that is the inferior version optically. Look for the older LD Di version.
The Sigma is still sharper than either at wide apertures. Results are available on DXOMark but I'm not about to hunt for them again. I went through all that before I made the purchase. I also found corresponding opinions on several pro review sites.

Last edited by audiobomber; 06-24-2015 at 02:01 PM.
06-24-2015, 02:05 PM   #13
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QuoteOriginally posted by audiobomber Quote
The Sigma is still sharper than either at wide apertures. Results are available on DXOMark but I'm not about to hunt for them again. I went through all that before I made the purchase. I also found corresponding opinions on several pro review sites.
That might be true, but the OP's question was, "why is this Tamron not as good as the one I used to have?" I'm just answering his question...

The price of the SIgma has come down, so it is clearly a good deal right now. Being about the same price as the Tamron these days, the Sigma is a good option indeed.
07-10-2015, 11:36 AM   #14
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Hello again. I'm doing some concurrent research but would appreciate knowing which Sigma 18-50 / 17-50 as there appear to be subtle variations.
Many thanks for your time and thoughts,
John
07-10-2015, 11:53 AM   #15
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The 18-50 is the older model. I don't think you want that one, the 17-50 is supposedly quite a bit better. The Sigma 17-50 is relatively new, so you don't have different optical versions, as far as I know - unlike the Tamron.

As a curiosity, what do you think makes the Canon 1000D a better astrophotography camera than the Pentax?
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