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09-26-2012, 06:16 AM   #1
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Tamron 90mm variants

There’s a Tamron 90mm SP AF 2.8 on ebay but its not the newer Di . Anyone familiar with the differences?


Last edited by no694terry; 09-26-2012 at 07:27 AM.
09-26-2012, 07:04 AM   #2
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better will be tamron 60/2, i thing, have IF and is cheaper
09-26-2012, 07:26 AM   #3
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Doesnt look like the plan a pentax mount for that one
09-26-2012, 07:36 AM   #4
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There is a 90 Di in the marketplace at the moment ()

I think one of the biggest differences is coatings optimized for digital. Not sure if the older version has the focus limiter either

09-26-2012, 08:29 AM   #5
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QuoteOriginally posted by no694terry Quote
There’s a Tamron 90mm SP AF 2.8 on ebay but its not the newer Di . Anyone familiar with the differences?
AF lenses with no Di or Dii classification are full frame lenses released prior to digital cameras and full frame or cropped sensors.

the difference is as a minimum that the coatings on the rear element are not specifically designed to avoid reflection and loss of contrast due to the sensor (and uv filter in front of it) being more reflective than film.

a similar issue exists with Sigma.

For general information note the following

No Designation = film lens
Tamron Di or Sigma DG = Full frame with coatings for Digital
Tamron Dii or Sigma DC = Cropped Sensor with coatings for Digital
09-26-2012, 09:37 AM   #6
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QuoteOriginally posted by Lowell Goudge Quote
...

No Designation = film lens
Tamron Di or Sigma DG = Full frame with coatings for Digital
Tamron Dii or Sigma DC = Cropped Sensor with coatings for Digital
Thanks Lowell for the info ... didn't previously quite grasp/notice what the Dii difference was ... got it now.
09-26-2012, 09:42 AM   #7
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QuoteOriginally posted by Lowell Goudge Quote
AF lenses with no Di or Dii classification are full frame lenses released prior to digital cameras and full frame or cropped sensors.

the difference is as a minimum that the coatings on the rear element are not specifically designed to avoid reflection and loss of contrast due to the sensor (and uv filter in front of it) being more reflective than film.
While true - I believe several users (not just Pentax users) have determined that the difference in effect from the Di coatings is negligible between the older and new lens. More than likely, it's not a lens that easily reflects due to the element placements and lens construction (Macro lenses tend to be very deep-set with their front element).

And since the glass is the same between the older and the newer, there is very little to distinguish in image quality between the two. The benefit of the newer lens, however, is that the Di has a bit nicer build (not as plastic) and looks cooler.

QuoteOriginally posted by Deimos Quote
There is a 90 Di in the marketplace at the moment ()

I think one of the biggest differences is coatings optimized for digital. Not sure if the older version has the focus limiter either
It did.
09-26-2012, 10:13 AM   #8
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QuoteOriginally posted by no694terry Quote
Doesnt look like the plan a pentax mount for that one
oh, my mistake... than DA 100/2,8 macro wr it is sharp wide open and aberating a bit

09-26-2012, 11:37 AM   #9
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QuoteOriginally posted by JinDesu Quote
While true - I believe several users (not just Pentax users) have determined that the difference in effect from the Di coatings is negligible between the older and new lens. More than likely, it's not a lens that easily reflects due to the element placements and lens construction (Macro lenses tend to be very deep-set with their front element).
it is not a question of a deep set front element, although that helps as it acts as a natural hood, but a question of the ghosting and reflection that may come off the sensor and be reflected back by the rear element.
QuoteQuote:
And since the glass is the same between the older and the newer, there is very little to distinguish in image quality between the two. The benefit of the newer lens, however, is that the Di has a bit nicer build (not as plastic) and looks cooler.
i will leave the astetics aside, each lens builder has their own approach, my sigma APO 70-200/2.8 EX (non DG) is identical to the DG version except for coatings. there is no difference in IQ between the two, however later DG Macro versions were not as sharp due to changes in optical formulas as well
09-26-2012, 03:30 PM   #10
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My 17-50 is a Di for aps-c I thought. Dont remember seeing Dii
09-27-2012, 10:57 AM   #11
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17-50 is Di II... Tamron SP 17-50mm F/2.8 Di II (model A16)

As for the Di vs. previous versions of 90mm f/2.8 macro, they're pretty much all the same optical formula. Comparison here: Variations of Tamron 90mm Macro lenses
09-27-2012, 05:37 PM   #12
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QuoteOriginally posted by Lowell Goudge Quote
it is not a question of a deep set front element, although that helps as it acts as a natural hood, but a question of the ghosting and reflection that may come off the sensor and be reflected back by the rear element.
I agree.
I haven't really tried the Di 90/2.8, but I've used the old Adaptall SP 90/2.5 a fair bit and under certain conditions (mainly indoor product photos) I would get a large circular greenish bright area in the middle of the frame. I think the Di, DG, DA coating are supposed to correct this. I've also had this issue a bit with a FA 50/1.4
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