[Pentax Bob]

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I just saw a listing for sale for a Tamron lens that I have never seen listed anywhere. It is a Tamron SP 28- 105 mm f 2.8 model 176 A. Does anyone know anything about this lens? Is it an Adaptall lens or a fixed mount? Auto focus or manual?

It sounds like just what I am looking for. It is not in the lens data base or on Adaptall.org

Any info would be appreciated.

Thanks,

Pentax Bob

[jane7l]

google it. looks like this is the one:

Tamron SP 28-105mm f/2.8 LD Adaptall 2 IF manual focus on eBay (end time 23-Jan-11 00:18:38 GMT)

Tamron 28-105mm f/2.8 LD Aspherical IF MF Adaptall Lens A76100

ciao

[pacerr]

Google "Tamron 176A" for threads and reviews.

Discontinued in 2002.

Generally considered a well constructed, SP-quality Tamron lens but IMO a little pricey for a MF lens today unless you have a special desire for the Adaptall SP lenses. This would be a noticeably large and heavy lens on the more compact DSLR bodies.

The speed and FL range are appealing though.

I believe I recall Jim King acquiring one of these a while back - you might PM him.

H2

[Jewelltrail]

According to the information here http://http://forum.manualfocus.org/viewtopic.php?id=15007 here is an AF version of the lens. Both versions are said to be a bit soft wide open. This thread is dated, but should be of some help to you--good luck, those adaptall lenses can be mighty fine.

[Pentax Bob]

I have seen listings and photographs of a Tamron AF SP 28-105 mm f 2-8 in Canon and Nikon mounts. I would like to know if it was produced in a Pentax mount. I contacted Tamron about it, but have not reply as of yet. Does anyone have one? Does it live up to the SP label? I am reasonable sure it is no longer in porduction. If it is a reality please write a review and add it to the lens data base.

I could not find the information you mention in the link provided.

Thanks anyway

Pentax Bob

[wlachan]

Like the SP35-105/2.8, both looked good on paper but not that great optically or well made inside despite their metal barrels. In fact, I don't remember a single well made SP lens in 2 decades, even though Tamron had no problem to come up with a few gems.

[Jewelltrail]

I have seen listings and photographs of a Tamron AF SP 28-105 mm f 2-8 in Canon and Nikon mounts. I would like to know if it was produced in a Pentax mount. I contacted Tamron about it, but have not reply as of yet. Does anyone have one? Does it live up to the SP label? I am reasonable sure it is no longer in porduction. If it is a reality please write a review and add it to the lens data base.

I could not find the information you mention in the link provided.

Thanks anyway

Pentax Bob

Bob, the theunartist recently posted a shot in here https://www.pentaxforums.com/forums/pentax-slr-lens-discussion/31955-tammy-cl...ml#post1354326 Post number 1231

He says it is done with a Tamron 28-105 and nothing more. You could PM him for more information.

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Last edited by Jewelltrail; 01-24-2011 at 09:37 PM.

[Jewelltrail]

wlachan: In fact, I don't remember a single well made SP lens in 2 decades, even though Tamron had no problem to come up with a few gems.

I am confused by this sentence--can you please help me? Thanks.

[wlachan]

I am confused by this sentence--can you please help me? Thanks.

Tamron SP lenses used to be well designed and well made back in the Adaptall era. When the AF era came, they seemed to have a blank and both optically and built quality dropped dramatically. After a long struggle, they came up with a few hallmark designs like SP28-75/2.8, SP17-50/2.8, SP180/3.5 & SP70-200/2.8. But their lenses have since cut so many corners on built quality, optically misalignment and AF error have become the norm.

[Jewelltrail]

Tamron SP lenses used to be well designed and well made back in the Adaptall era. When the AF era came, they seemed to have a blank and both optically and built quality dropped dramatically. After a long struggle, they came up with a few hallmark designs like SP28-75/2.8, SP17-50/2.8, SP180/3.5 & SP70-200/2.8. But their lenses have since cut so many corners on built quality, optically misalignment and AF error have become the norm.

Thank you for explaining the sentence. I own 5 Tamron SP lenses, and love them all. Next to my 23a, 60-300mm Adaptall, the SP 24-135mm f 3.5-5.6 is probably built the most ruggedly. but all the others are built very well. A lens no longer has to weigh a ton, iin order to have nice build quality--this is the 21st century.

The 17-50 & 28-75 f 2.8 lenses exceed my build quality needs. I know the 17-50mm is a lot lighter than the Da 16-50, something from which I benefit when I hike 10 or more miles. with 4 thousand feet of elevation gain. BTW, the 28-75 I own worked pefectly on 2 bodies before I put it on my K20d, where it FF horribly. This tells me that the focus issues are not always because of the lens-maker; rather, the camera body maker plays a role in ths too.

I only bought 1 Tamron 17-50mm, and have since taken over 15,000 shots with it--the lens is awesome--I would not give it to you in exchange for 2, brand new 16-50s.

[Pentax Bob]

I got a reply today from Tamron about the 28-105 AF SP. They said it was not made in a Pentax mount. Also said it was replaced with the 28 -75 SP because the 28-105 did not work well with digital sensors. Looks like Sigma 28 -105 2.8 -4 is the closest available.

[clockwork247]

I got a reply today from Tamron about the 28-105 AF SP. They said it was not made in a Pentax mount. Also said it was replaced with the 28 -75 SP because the 28-105 did not work well with digital sensors. Looks like Sigma 28 -105 2.8 -4 is the closest available.

i have the sigma in question, tested a few times, it's actually as sharp as my kit lens wide open, so i decided to keep it (some people said the 28-70 f/2.8 sigma isn't sharp at the tele range (70), and it should be 2.8-4, hehe, so i saved a bit of money using this lens).

[Jewelltrail]

Pentax Bob: I got a reply today from Tamron about the 28-105 AF SP. They said it was not made in a Pentax mount. Also said it was replaced with the 28 -75 SP because the 28-105 did not work well with digital sensors. Looks like Sigma 28 -105 2.8 -4 is the closest available.

Bob, there is an Auto-focus Tamron, model 276D, 28-105 f 2.8 lens. Also, there is a Manual Focus Adaptall 2 lens, model 176a, 28-105 f 2.8. The former was discontinued in 2004, the latter in 2002.

In your opening post you labeled the lens you were seeking as this: "It is a Tamron SP 28- 105 mm f 2.8 model 176 A." That lens is a MF lens, & is an Adaptall 2 mount--this means it wil fit all the major mounts, with the correct adapter. These are still available--I read about them now and then and, if patient, you can get one for your Penatx body--most likely used, but "new" ones surface as well.

However, the Tamron 276d AF lens, 28-105 f2.8 is another story. I suspect this is the lens about which Tamron responded to you on the phone. So, I have these questions for you:

Do you want the 276d model or the 176a model?
Do you really need f 2.8, constant, for the entire 28-105 range?

As others have said, the 176a lens is very pricey for a MF lens--surely there are better options. If you are very precise about your actual needs, there are many excellent people here who will point you in the right direction.

[Pentax Bob]

Thanks for all the information. It seems the model 276D is not available in Pentax mount and was not updated. I have read some not so good things about the 176A such as very heavy, manual focus and very expensive.

I think after all this what I want is the Sigma 28 -105 f2.8 -4. This seems like the best lens in this FL range. All I need now is to fine one for sale at an affordable price.

Pentax bob