Which way do Tamron zoom rings work?

Quick question, but do Tamron lenses zoom in the same direction as native Pentax lenses?

I heard sigma goes in the opposite way to us?

Considering a kit lens upgrade to a Tamron 17-50 f2.8 lens, or a sigma 17-70 f2.8-f4.0

Keeping the same zoom direction will help with muscle memory. Ie going the other way will likely annoy me

Any thoughts on those lenses (Tamron seems cheaper construction for example) appreciated also. Understand neither are WR sealed.

Tamron looks to use screw drive AF, whereas Sigma has HSM motor etc. Assume no issues with sigma motors like some of the past Pentax motors.

Thanks.

Thanks.

My Tamron 70-200 goes the same way as the Pentax 28-105! Can't comment on the specific lenses though.

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Andy

I get really confused by the differences in which way the focusing mechanisms on Sigma and Pentax/Tamron work (?) - that's probably why most of my lenses are Sigma
PS: OTOH, for some reason, I've never had any Tamron lenses

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K-3 II, K-3 and a K-70 from SRS (having now relegated the K-30 /"K-50" to a backup body), & some Sigma and Pentax lenses (and a lot of old 35mm gear!)

All my tamron lens 70-200 2.8 17-50 2.8 & 10-20 zoom the same way as pentax also my sigma 24-70 2.8 zooms the same way as well
hope this helps

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k1 k5iis
8mm fisheye pentax da 12-24 sigma 15mm tamron 17-50 tokina 20-35 pentax fa 24-90 tokina 28-70 atx pro
Pentax A 135 sigma ex dg 100-300 f4 pentax fa 50 1;1;7 pentax A 501;1;4 pentax A200f4 sigma 70-200 apo ex 2.8 sigma af 400mm pentax 1.7 af adapter
Pentax af aw 1.4 rear converter and a flash

Argh, lots of info to digest.

Anyone have the sigma 17-70 or 17-50? Does it turn the same way as the Pentax kit? I’d heard it turned the opposite.

Sounds like the Tamron 17-50 goes the same way as the Pentax.

Keen to upgrade the kits lens with one of these. Budget is an issue as always, so now to find a second hand bargain
I’m heading to Hong Kong and Vietnam soon and wonder if I can find a deal there, maybe even new, but expect to be weary to of the humidity there.

Got an old 17-70 Sigma, and (IIRC) it turns the same way as my other Sigmas - i.e. opposite to Pentax !

PS, I love it, and hope to - and be happy to - take it to a humid climate like Vietnam later this year, and would obviously take "precautions" in those circumstances because it is not WR.

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K-3 II, K-3 and a K-70 from SRS (having now relegated the K-30 /"K-50" to a backup body), & some Sigma and Pentax lenses (and a lot of old 35mm gear!)

It's an important detail if we are to work fast and without confusion between lenses.

Some manufacturers actually have different versions for different fits - Zeiss do on their Canon and Nikon variants, which turn opposite ways.

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Best regards, John

Yeah, may sound petty, but I've got other things to be thinking about than which way do I have to turn this one.

Tamron pros seem to be price, zooms the same direction. Cons are some references to front/back focus requiring calibration (hope it's linear and can be adjusted), plastic build quality and noisy screw drive AF.

Sigma pros seem to be build quality, and quiet motor. Cons are price, and turns the 'wrong way'.

I think the Tamron 17-50/2.8 zooms the same way as Pentax while the Sigma zooms the opposite way. For what it's worth, if it's within your budget and you don't mind the extra size and weight, the Sigma is overall a better lens, though the Tamron is no slouch.


I used my Tamron 17-50/2.8 in Vietnam and can offer a couple of pieces of advice. In the evening, when you're back in your air conditioned hotel, leave camera and lens(es) open and unmounted so that any accumulation of moisture inside can evaporate. Secondly, your Tamron won't survive five seconds if it gets caught out in a south-east Asian torrential downpour - they are impressive and can swoop in very fast, especially in the early evening (I went in May). Not even a WR lens and camera could survive one of them, so take cover and wait them out and make sure that camera bag/backpack has a well-fitting plastic cover to keep your gear dry.

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Pentax hybrid user - Digital K3, film 645 and 35mm SLR and Pentax (&other) lenses adapted to Fuji X and Panasonic L digital
Fan of DA limited and old manual lenses

I don’t mind the weight difference, and just say the sigma was my first choice.

Wanted the Pentax 16-85 WR until I saw the price, and then the Pentax 18-135. That said, neither are f2.8 and has a longer zoom range, so it’s not really apples for apples.

Really appreciate the Vietnam downpour tips. Thanks.

The 18-55 f/3.5-5.6 kit lens on my old K-x increases focal length with a clockwise turn (as seen from behind the camera). The Sigma 17-50 f/2.8 on my K-S2 zooms the opposite way. As I am a slow deliberate photographer the difference doesn't bother me, but I can see that it would be a disadvantage when grabbing a fleeting shot.

I have mixed feelings about my Sigma. The constant f/2.8 is nice to have, but mine is not particularly sharp. I think I may have one that only just passed QC, as the un-sharpness is noticeably worse at one edge compared to the other edge. However, as a general purpose midrange zoom it is quite handy to have as the normal 'carry on camera' lens.

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A few of my photographs in flickr.
Lizars 1910 "Challenge" quarter-plate camera; and some more recent stuff.

Yes I’m strongly considering the Sigma 17-70 having read all these comments.

It’s f2.8-4.0, but I like the idea of the more versatile focal length over the 18-55 kit.

A huge amount of posts re the Tamron back/front focussing inconsistently throughout the zoom range, which you can’t fix with a single specific lens calibration correction. I’ll have little chance to seek warranty type assistance, so want to get it right when I take that gamble.

There are 3 variants, but definitely after the HSM motor one. The newer contemporary style one looks quite nice.

Don't know if you have already read them, but the Pentax Forums reviews of all three versions can be found here:

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K-3 II, K-3 and a K-70 from SRS (having now relegated the K-30 /"K-50" to a backup body), & some Sigma and Pentax lenses (and a lot of old 35mm gear!)

You should always check any new (or used) lens for focus issues and edge-to-edge performance either before buying or at least before your option to return it expires. This goes double for third-party lenses such as Tamron or Sigma - if you get a good one then it should be fine but I've experienced problems myself and read a lot of comments online too, so always check.

The ideal situation is to go to a physical shop where they have multiple copies and try before you buy, but that's not always possible (especially with Pentax).

I can't say if there's any difference in this respect between Tamron and Sigma, I doubt there's much. I've had the occasional problem with Pentax lenses too but I'm still more wary of the third-party ones.

The Sigma 17-70mm gets good reviews too, though I like the constant aperture of the f/2.8 zooms and am prepared to sacrifice that extra 20mm for an extra stop of light.

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Pentax hybrid user - Digital K3, film 645 and 35mm SLR and Pentax (&other) lenses adapted to Fuji X and Panasonic L digital
Fan of DA limited and old manual lenses