Sigma 105mm OR Tamron 90mm

Advice please. I'm looking for a macro lens for my K100d.

I have decided on either Sigma 105mm F2.8 EX DG Macro Lens or Tamron SP 90mm F2.8 Macro 1:1 Di

Which would be the best lens?

Any advice would be a big help to me.

Thanks

I keep considering the FA100-2.8macro against the Tamron 90mm... Can't quite remember why I discounted the Sigma but I'm sure there was a reason...

I'm on the lookout for the FA myself...

Would suggest you use flickr.com to search and compare images and see which you prefer...

All 1/1 macro's tend to be sharp as nails... For me it came down to the colours that the FA reproduced... I want one!!

There's a great many macro shooters around though who'll give much better advice than me, so I'll do one...

The truth is, either of them would probably suit you equally well. The focal length difference of 15mm might make a difference and I'd probably choose that if I were faced with your dilemma.

My own preference is 180mm but If I were buying today, I'd go for the Sigma 150mm (if they still make it in Pentax fit).

I can't help with distinguishing between the 2. I own the Tamron and found its image quality excellent. However, I don't enjoy its mechanics for switching from manual to auto focusing. The pushing of the focus ring to engage the clutch is fine to select MF, but it doesn't disengage the drive screw and you also have to select MF on the body to prevent turning the drive motor whilst focusing.

I have found no way to gain the usefulness of focus trapping with this lens without the introduction of an extension tube.

Either or. Both are great lenses with virtually no difference in IQ. Let price be your deciding factor.

srs have the siggy on offer at £299,
http://www.srsmicrosystems.co.uk/134/Sigma-105mm-F2-8-EX-DG-Macro-Lens---Pentax-...

I just phoned my local independant camera shop to enquire about the sigma and tamron lenses and the person there told me that these two macro lenses would not be suitable for a digital pentax camera when using for macro work. He said that they are full frame lenses and this would mean that I wouldn't get the same macro results on my camera.
Can anyone shed any more light on this for me please?

I'd guess you're local shop doesn't know what he's talking about?

Rubbish see the photo's with mike-p's with the sigma....
https://www.pentaxuser.com/photo/user-6020/damsel----in-no-distress-32124

is this good enough
check out the gallery
https://www.pentaxuser.com/user/mike-p-6020

Then he's wrong.

The Tamron 90/2.8 is suitable for the K10D, K5 and as far as I can tell from the forum, just about every other DLSR that members own. Just look back through some of the pictures posted.

As to the Sigma, I dont have one, but many do so I would expect the sentence above applies as well.

Bernard

full frame lenses work,
but the other way round APS-C lenses on full frame may not work properly

Think Mike's picture was actually taken with the Pentax DFA 100mm Macro that he sold recently

I've been looking at the same lenses - if you search on Flickr using the lens name, it will come up with lots of different images taken...quite a useful comparison tool..

You will get different results from a full frame compared to crop but that is purely down to sensor size. To say neither lens is suitable for Pentax digital is absolute rubbish though. Both are excellent lenses and either will no doubt get you very good results.

The only let down imo is the outside coating on the Sigma body which has a tendency to rub with a lot of use.

I use the Sigma 105mm F2.8 EX DG and it's a great lens. It was my most used lens all last summer after I got bitten by the macro bug!

I would avoid that shop like the plague in future (or at least that guy) as he is talking out of his rear basically.

Check out the macro on my Smugmug below - all taken with K7/K5 and the Tamron 90. But the Sigma 105 would do the same job equally as well.