Igitabo cyo gusesengura umurongo wa MTF

Igishushanyo mbonera cya MTF (Modulation Transfer Fonction) ikora nkigikoresho gikomeye cyo gusesengura cyo gusuzuma imikorere ya lens. Mugereranya ubushobozi bwa lens bwo kubika itandukaniro muburyo butandukanye butandukanye, irerekana muburyo bugaragara ibintu byingenzi byerekana amashusho nko gukemura, ubudahemuka butandukanye, no guhuza impande zose. Hano haribisobanuro birambuye:

I. Gusobanura Imirongo Ihuza Imirongo

Axis ya Horizontal (Intera iri hagati)

Iyi axe yerekana intera kuva hagati yishusho (guhera kuri 0 mm ibumoso) kugera kumpera (aho iherezo ryiburyo), ipimwa muri milimetero (mm). Kuri linzira yuzuye, hagomba kwitabwaho cyane cyane kuva kuri 0 kugeza kuri 21 mm, bihuye na kimwe cya kabiri cya diagonal ya sensor (43 mm). Kuri lens ya APS-C, urwego rujyanye nubusanzwe rugarukira kuri mm 0 kugeza kuri 13, byerekana igice cyo hagati cyuruziga.

Axis Vertical (Agaciro MTF)

Uhagaritse umurongo werekana urwego lens ibika itandukaniro, kuva kuri 0 (nta tandukaniro ryabitswe) kugeza kuri 1 (kubika neza itandukaniro). Agaciro ka 1 kerekana icyerekezo cyiza kidashobora kugerwaho mubikorwa, mugihe indangagaciro zegereye 1 zerekana imikorere isumba iyindi.

Ubwoko bw'ingenzi bwo kugorora

Inshuro yumwanya (Igice: imirongo ibiri kuri milimetero, lp / mm):

- 10 lp / mm umurongo (uhagarariwe numurongo wijimye) yerekana lens muri rusange ubushobozi bwo kubyara. Agaciro MTF iri hejuru ya 0.8 muri rusange ifatwa nkibyiza.
- Umurongo wa 30 lp / mm (ugereranwa n'umurongo muto) werekana imbaraga za lens zo gukemura no gukomera. Agaciro MTF karenze 0,6 ifatwa nkibyiza.

Icyerekezo cy'umurongo:

- Umurongo ukomeye (S / Sagittal cyangwa Radial): Yerekana imirongo yikizamini irambuye hanze yikigo hagati (urugero, bisa nkibisobanuro ku ruziga).
- Umurongo Utudomo (M / Meridional cyangwa Tangential): Yerekana imirongo yikizamini itondekanye muruziga (urugero, impeta isa nimpeta).

II. Ibipimo byo gusuzuma imikorere

Uburebure

Intara yo hagati (Ibumoso bwa Horizontal Axis): Indangagaciro za MTF zo hejuru kuri 10 lp / mm na 30 lp / mm umurongo werekana amashusho akomeye. Indangantego zohejuru zikunze kugera kuri MTF yo hagati hejuru ya 0.9.

Agace k'Impande (Uruhande rw'iburyo rwa Horizontal Axis): Kwiyongera kwagaciro ka MTF kugana kumpande bisobanura imikorere myiza. Kurugero, impande MTF ifite agaciro ka 30 lp / mm irenze 0.4 iremewe, mugihe kurenga 0,6 bifatwa nkibyiza.

Gukata neza

Inzibacyuho yoroshye hagati yikigo nuruhande byerekana imikorere ihamye yo kwerekana amashusho kumurongo. Kugabanuka gukabije byerekana igabanuka rikomeye mubishusho bigana kumpera.

Gufunga S na M Imirongo

Kuba hafi ya sagittal (umurongo uhamye) hamwe na meridional (umurongo ucagaguye) umurongo werekana lens ya astigmatism igenzura. Guhuza hafi bivamo bokeh karemano no kugabanya aberrasi. Gutandukana gukomeye gushobora kuganisha kubibazo nko guhumeka neza cyangwa ibihangano byumurongo.

III. Ibintu Byongeyeho Ingaruka

Ingano ya Aperture

Ubushobozi ntarengwa (urugero, f / 1.4): Birashobora gutanga umusaruro mwinshi hagati ya MTF ariko bishobora kuviramo kwangirika bitewe na optique.

Ibyiza Byiza (urugero, f / 8): Mubisanzwe bitanga imikorere iringaniye ya MTF murwego kandi akenshi igaragazwa mubururu ku gishushanyo cya MTF.

Kuzamura Lens Guhinduka

Kuri zoom zoom, imirongo ya MTF igomba gusuzumwa ukwayo kumurongo mugari na terefone ya terefone, kuko imikorere ishobora gutandukana nuburebure bwibanze.

IV. Ibitekerezo by'ingenzi

Imipaka yisesengura rya MTF

Mugihe MTF itanga ubushishozi bwingirakamaro mugukemura no gutandukanya, ntabwo ibara izindi nenge zidahwitse nko kugoreka, gukuramo chromatic, cyangwa flare. Izi ngingo zisaba isuzuma ryinyongera ukoresheje ibipimo byuzuzanya.

Kugereranya ibicuruzwa

Bitewe nuburyo butandukanye bwo gupima uburyo nubuziranenge mubakora, hagomba kwirindwa kugereranya mu buryo butaziguye umurongo wa MTF ku bicuruzwa bitandukanye.

Gukata umurongo no kugereranya

Imihindagurikire idasanzwe cyangwa asimmetrie mumirongo ya MTF irashobora kwerekana inganda zidahuye cyangwa ibibazo byo kugenzura ubuziranenge.

Incamake yihuse:

Ibiranga Lens-Performance Lens:
- Byose 10 lp / mm umurongo biguma hejuru ya 0.8
- Hagati 30 lp / mm irenga 0.6
- Impande 30 lp / mm irenga 0.4
- Imirongo ya Sagittal na meridional irahujwe cyane
- Koroha kandi buhoro buhoro MTF yangirika kuva hagati kugeza kuruhande

Isuzuma ryibanze ryibanze:
- Hagati ya 30 lp / mm agaciro
- Impamyabumenyi ya MTF attenuation
- Kuba hafi ya S na M.

Kugumana indashyikirwa muri ibyo bice uko ari bitatu byerekana neza igishushanyo mbonera cyiza kandi cyubaka ubuziranenge.