稻草人的天空: 微距的世界--Tamron SP 90mm F2.5

不知何時也迷上了拍微距,手中的MINOLTA MC/MD系統沒有入手微距鏡

因為當時在底片機時代,對拍微距沒啥興趣,直到入手E1後,衝著方便性

也想找顆來玩玩,當時在eBay找了一段時間後,MINOLTA原廠的MC/MD 50mm f3.5 macro

價格還不是很平易近人,盯了好幾隻,不是被攔胡,就是價格超出預算..XD

於是把目標轉到了副廠的微距鏡頭上了,網路搜尋的一些資料及範例照交叉比對後

決定把目標訂在這隻 TAMRON SP 90mm F2.5(1:2),若要達到1:1的放大倍率

需再加上2X Tele-Converter增距鏡.

鏡頭相關官方規格資料如下:

TAMRON SP 90mm F2.5

Lens Specifications:

Lens Model	52B
Focal Length	90mm
Aperture Range	f/2.5 — 32, AE
Angle of View	27°
<NOBR>Optical Construction (Groups / Elements)</NOBR>	6 / 8
<NOBR>Min. Focus fromFilm Plane</NOBR>	15.3" (0.39m)
<NOBR>Macro Mag. Ratio [w/2X Converter]</NOBR>	1:2 [1:1]
Filter Size	49mm
Diameter	2.5" (64.5mm)
<NOBR>Length at Infinity in. (mm) w/Nikon mount</NOBR>	2.6" (66mm) [2.8" (70.5mm)]
Weight	14.8 oz. (420g)
Lens Hood	Screw-in type #23FH (optional extra).
Accessory	Accepts SP 2X tele-converter #01F.

CLASS="head">Tamron SP 90mm F/2.5
CLASS="axis1">F/no.	CLASS="title">RESOLUTION at 1:48 magnification		CLASS="title">CONTRAST (30 lines/mm)
CLASS="axis1">F/no.	CLASS="title">Center Lines/mm	CLASS="title">Corner Lines/mm	Center %	Corner %
2.5	49	55	49	28
4	62	55	72	54
5.6	62	55	76	60
8	69	62	66	55
11	69	62	64	52
16	62	62	53	47
22	55	49	45	40
32	44	44	33	30

COLSPAN="3">Tamron SP 90mm F/2.5
CLASS="axis1">F/no.	CLASS="title"><NOBR>MACRO RESOLUTION</NOBR> at 1:4 magnification
CLASS="axis1">F/no.	CLASS="title">Center Lines/mm	CLASS="title">Center Lines/mm
2.5	41	46
4	58	52
5.6	65	52
8	58	58
11	58	58
16	58	52
22	52	52
32	52	52

CLASS="head">Tamron SP 90mm F/2.5
CLASS="axis1">F/no.	CLASS="title"><NOBR>MACRO RESOLUTION</NOBR> at 1:2 magnification
CLASS="axis1">F/no.	CLASS="title">Center Lines/mm	CLASS="title">Center Lines/mm
2.5	33	33
4	37	33
5.6	47	33
8	53	47
11	59	59
16	59	59
22	53	53
32	53	47

2X Tele-Converter

Lens Specifications:

Lens Model	01F
Focal Length	2X the focal length of original lens
Aperture Range	f/5 — 64, AE (Original lens F number x 2)
Angle of View	—
<NOBR>Optical Construction (Groups / Elements)</NOBR>	5 / 6
<NOBR>Min. Focus from Film Plane</NOBR>	Retains the min. focus of original lens.
<NOBR>Macro Mag. Ratio</NOBR>	2X the mag. ratio of original lens.
Filter Size	—
Diameter	2.5" (64.5mm)
<NOBR>Length at Infinity in. (mm) w/Nikon mount</NOBR>	1.7" (42.5mm) [1.9" (47mm)]
Weight	8.8 oz. (250g)
Lens Hood	—
Accessory	—