If this is your first visit, be sure to check out the FAQ by clicking the link above. You may have to register before you can post: click the register link above to proceed. To start viewing messages, select the forum that you want to visit from the selection below. |
|
|
Thread Tools | Display Modes |
|
#1
|
|||
|
|||
Macro wide open - ??
On Fri, 01 Jun 2018 07:48:35 -0700, Whisky-dave
wrote in : On Friday, 1 June 2018 14:59:18 UTC+1, Paul Carmichael wrote: I'm sure this has been done to death before, but here goes... Why does my macro lens (Tamron SP90) open up to 2.5? Does it ? as it seems to state f2.8 on the web. It could be that the firmware of the camera has access to the lense T value in its database. PC uses a fairly modern EOS 6D mark II, IIRC. There is according to DxO Mark two different Tammies 90SP one T/3.0 and the other, newer T/3.3. The latter would be more like 2.5 rather than 2.8 if the former is used for reference... HTH! https://www.dxomark.com/lenses/brand...-between-1987- and-2018/mount_type-Canon_EF/focal-from-90-to-90/launch_price-from-0- to-13000-usd#hideAdvancedOptions=false&viewMode=list&yDataT ype=global -- teleportation kills |
#2
|
|||
|
|||
Macro wide open - ??
In article , android
wrote: Why does my macro lens (Tamron SP90) open up to 2.5? Does it ? as it seems to state f2.8 on the web. It could be that the firmware of the camera has access to the lense T value in its database. PC uses a fairly modern EOS 6D mark II, IIRC. There is according to DxO Mark two different Tammies 90SP one T/3.0 and the other, newer T/3.3. The latter would be more like 2.5 rather than 2.8 if the former is used for reference... HTH! or it could actually be f/2.5 http://www.adaptall-2.com/lenses/52B.html |
#3
|
|||
|
|||
Macro wide open - ??
|
#4
|
|||
|
|||
Macro wide open - ??
In article , android
wrote: Why does my macro lens (Tamron SP90) open up to 2.5? Does it ? as it seems to state f2.8 on the web. It could be that the firmware of the camera has access to the lense T value in its database. PC uses a fairly modern EOS 6D mark II, IIRC. There is according to DxO Mark two different Tammies 90SP one T/3.0 and the other, newer T/3.3. The latter would be more like 2.5 rather than 2.8 if the former is used for reference... HTH! or it could actually be f/2.5 http://www.adaptall-2.com/lenses/52B.html Sure. But that would not be reported from lense to camera. he didn't say it was reported to the camera. he only asked why it opens up to f/2.5, which is for a shallow depth of field and/or low light, like any other lens. |
#5
|
|||
|
|||
Macro wide open - ??
|
Thread Tools | |
Display Modes | |
|
|
Similar Threads | ||||
Thread | Thread Starter | Forum | Replies | Last Post |
[SI] Wide Open is now open for viewing | bowser | 35mm Photo Equipment | 3 | March 9th 09 12:43 PM |
[SI]: New Mandate: Wide Open | bowser | Digital Photography | 22 | February 14th 09 09:44 PM |
[SI]: New Mandate: Wide Open | bowser | Digital SLR Cameras | 22 | February 14th 09 09:44 PM |
DSLR lenses not good wide open at wide angle? | Alfred Molon[_4_] | Digital Photography | 7 | July 16th 08 01:29 PM |
Canon efs 60mm f2.8 macro underexposure wide-open | Geoffrey | Digital Photography | 0 | October 11th 06 11:57 AM |