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"Problemi" z ostrino Canon DSLR EOS kamer

Avtor:Matjaž Intihar
05.10.2003 13:34

Veliko se govori in piše o možni neostrini oziroma nepravilnem ostrenju s kamero EOS 10D in sedaj še s EOS 300D. In kaj je res.

Vseskozi že opozarjam, da se prepričajmo na lastnih izkušnjah, ali izkušnjah drugih, ki kamero že uporabljajo. In se govori, da digitalne kamere preden se sproži zaklop ne preverijo ostrino, da je zamik tipala drugačen kot film itd. Sam in kolegi ki 10D imajo smo preizkusili že vsaj 20 kamer in se je sedaj samo pri eni v začetku pojavila ta napaka. In še to samo pri starejših objektivih. (preberite si članek v 6.številki e-Fotografija, imate jo tudi v pdf datoteki na straneh e-Fotografija). Na predstavitvi v Londonu sem fotografiral s kar nekaj EOS 300D in različnimi objektivi.

 


 

 

 

Hiroshi Komatsuzaki, predsednik Canon Consumer Imaging Europe med pogovorom z novinarji na predstavitvi EOS 300D v Londonu.

Potrditev o težavah oziroma bolje rečeno zmožnostih in kakovostih EOS 10D sem dobil že na predstavitvi EOS 300D avgusta v Londonu. G. Hiroshi Komatsuzaki, predsednik Canon Consumer Imaging Europe je na vprašanje o težavah povedal: "Kot ste videli na prej predstavljenem videu je tudi glavni urednik fotografije pri podjetju Reuters povedal, da mnogi njihovi foto reporterji uporabljajo tudi EOS 10D". Mislite, da bi jih, če bi se pojavljal ta problem vsesplošno kot se piše.

 


 

 

Takaya Iwasaki (levo) glavni manager oddelka foto video za Evropo Srednji vzhod in Afriko v pogovoru z urednikom e-Fotografija.

G. Takaya Iwasaki glavni manager oddelka foto video za Evropo Srednji vzhod in Afriko se je prejšnji vikend, ko sem mu postavil vprašanje zakaj toliko govora o tem, samo smejal in odgovoril. "Veseli smo, da se o Canonu toliko piše, kupci pa v količini prodanih produktov povedo svojo oceno".

Tudi ta ocena pove vse o napihnjenih problemih predvsem na spletnih forumih.


 

In kakšen je uradni odgovor podjetja Canon.

Na pooblaščenem servisu za Canon foto video opremo 3A d.o.o. sem dobil uradni Canonov odgovor za vse, ki jih teži to vprašanje. Odgovor je kar v obliki angleških navodil za ostrenje, ki same po sebi povedo, kaj si Canon misli o tem problemu.

Samo ogledal sem si spodaj predstavljeno navodilo o ostrenju in dobil odgovor, ki kar malo na grobo pove vse. "NAUČITE SE OSTRITI".

In moje mišljenje: Kamere so imele in bodo imele produkcijske napake. Predvsem pa današnje digitalne, ki pred prihodom na trg še niti niso dobro preizkušene. Možno je, da starejši objektivi tudi canonovi z novimi programi v kameri niso kompatibilni. Pri do sedaj eni EOS 10, ki je imela problem, EF100 makro ni dobro ostril. Novi EF 28 - 200 pa je odlično deloval. Nekaj bo na tem. In še nekaj. Digitalni zapis na ekranih deluje marsikomu neostro, potem pa je na slikah vrhunska ostrina. Sam vedno dodam malu Unsharp filtra. Oglejte si pri Foto Format fotografije posnete z EOS 300D. Naredite mi z najboljšo film 35mm kamero, najboljšim objektivom in najboljšim filmov tako oster posnetek! Ga ne bo. Ker ima film pri tej povečavi že svoje omejitve.

In vedite. Konkurenca bi rada tudi svoj kos pogače. Tudi razni privrženci sprožijo vse mogoče zapise. In prav to se dogaja na internetnih forumih, tudi na forumu e-Fotografija. Marsikatero naše podjetje izkoristi za svojo promocijo ali zapis slabe besede za drugega kar preko dobro obiskanih forumov. Predvsem tisti, ki danes prodajajo opremo, vas znajo vsakodnevno poudarjati njihovo najboljšo ponudbo. In seveda veliki privrženci določebih znamk so najbolj uporni v produkciji nesmislov.

Na forumih so besede zastonj, zato jih kot take tudi jemljite. Z zvrhano mero distance in lastnega razmišljanja.


 

 In še uradni Canon-ov odgovor, ki sem ga dobil v pooblaščenem Canon servisu 3A. d.o.o.

Dear Madam / Sir,

Thank you very much for choosing Canon products. We have received your equipment for checking or AF (Auto-focus) complaint, and would like to inform you that the result is as indicated below.

  • The equipment is checked completely, however, there was no problem found.
  • The equipment is adjusted.

Depending on the shooting situation, the AF function cannot be used at full value. Please read through the following information, which explains how to make the best use of the AF.

AF Frame and AF Sensor's Characteristics

Since the EOS AF system is employed with high-performance AF sensors and a microcomputer, even beginners can take clear pictures without struggling to achieve focus at most occasion. All EOS digital cameras have multiple AF frames (focusing points) in the viewfinder. These make it possible to focus accurately when the subject is at the side of the picture or when holding the camera vertically.

EOS 10D Viewfinder (same for EOS 300D) 

Auto-focus Considerations

Although EOS Digital cameras have a precision AF system, Auto-focus can fail to achieve focus (in which case the focus confirmation light blinks) with certain subjects as outlined below.

Subjects difficult to auto focus:

(a) Low-contrast subjects (e.g. blue sky, solid-colour walls, etc.).

 

  

(b) Subjects in low light (e.g. dark rooms, night scenes).

 

  

(c) Subjects with an object in front of them (e.g. animals in a cage, etc.).

 

  

(d) Extremely backlit reflective subjects (car with a reflective body, etc.).

 

  

Camera Shake and Subject Shift

If the camera (camera shake) or the subject (subject shift) moves during shooting, the images are not sharp. Especially, when you enlarge the image on a PC monitor, camera shake or subject shift can be easily noticed.

 

  • Camera Shake

     

If the camera is moved unnecessary when shooting, the whole image will not be sharp.

 

  

To prevent camera shake, please hold the camera firmly and press the shutter button softly.

 

  

If you are using a telephoto or macro lens, a tripod is recommended to hold the camera. 

  • Subject Shift

If the subject is moved at the time of shooting, it causes subject shift. The difference with camera shake is that only the moved subject becomes blurred.

 

  

 

  

To prevent subject shift becoming noticeable on the image, please use a faster shutter speed.

 AF modes

 

One Shot AF

One Shot AF is for shooting still subjects.

The AF point, which achieves focus, will flash briefly and the focus confirmation light in the viewfinder will light at the same time.

If the subject or the camera moves after the focus is achieved, the image will not be sharp unless the AF sequence is started again.

AI Servo AF

AI Servo AF is for shooting moving subjects.

With predictive AF, the camera can also focus and track a subject that steadily approaches or retreats from the camera.

In order to get sharp images, it is important to keep tracking the subject with the AF frame.

AI Focus AF

The AI Focus AF mode switches automatically from One Shot AF to AI Servo AF if the subject starts to move.

In order to get sharp images, it is important to keep tracking the subject with the AF frame. (This mode is available on the EOS D60, 10D and 300D.)

Note:

With EOS 300D, the suitable AF mode will be automatically selected, according to the shooting mode. Please refer to the User Manual (Pg.123) for details.

 

FAQ

 

 

Question

Answer

  • When checking an image on a PC monitor, it will be sharp when viewed at normal (small) size. However when viewed at enlarged size it seems out-of-focus.
  • There was no problem with film cameras. However, pictures taken with a digital SLR camera seem out-of-focus.

In most cases, the pictures taken with film cameras are printed out and then checked.

On the other hand, images of digital cameras are mostly enlarged and checked on a PC monitor. Although the AF precision is about the same, a slight focus difference will cause blur or "unsharpness" when the image is enlarged and exaggerated too much.

Please print the image to check its sharpness.

  • The images seem unsharp.
  • Compared to the images shot with compact digital cameras such as PowerShot, the images of digital SLR cameras seem unsharp.
    Are the digital SLR cameras inferior to compact digital cameras?

Images of Canon digital SLR cameras are emphasizing on the fidelity of the subject. Therefore they may seem unsharp at first sight. (They can however be retouched to sharp images.)

If you prefer not to retouch the images afterwards, please set the contrast and sharpness to <+> side using the parameter setting of the camera.

Please refer to the User Manual of the camera for details about parameter settings.

  • I performed some test shooting and found that the focusing point shifts to the front and back.
  • I can't focus on the desired area.

Please try a test shooting with portraits or landscapes.

The focusing point has a certain tolerance, so the focusing point may slightly shift to the front or back.

 
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