Results 1 to 14 of 14

Thread: 70-210mm f4-5.6 -- shooting at f4@210mm

  1. #1

    Default 70-210mm f4-5.6 -- shooting at f4@210mm

    hi,

    straight to the point.

    lens: 70-210mm f4-5.6 - with aperture ring

    i shot @ 210mm using f4 and 5.6 the only diff i see was that the @f4 it is more exposed (which is correct) but of cause it is a f4-5.6 lens so there has to be reason it should be f5.6 @ 210mm. so can someone enlighten me regarding this issue?

    ps. i am afraid that i forget to switch to f5.6 @210mm when i shoot on my slr. is there any issue like distortion, fade edges or whatever that is suppose to be happening?

    thanks.

  2. #2

    Default Re: 70-210mm f4-5.6 -- shooting at f4@210mm

    does anyone has an answer? or did i post it in the wrong section of the forum? :/

  3. #3

    Default Re: 70-210mm f4-5.6 -- shooting at f4@210mm

    forgive me if i'm wrong, but an f4-5.6 lens means that the maximum aperture at 70mm is f4, while the maximum aperture at 210mm is f5.6. So how is it possible for you to obtain f4 at 210mm? could you phrase your question differently? i'm afraid i don't understand it.

  4. #4

    Default Re: 70-210mm f4-5.6 -- shooting at f4@210mm

    Quote Originally Posted by xenith0 View Post
    forgive me if i'm wrong, but an f4-5.6 lens means that the maximum aperture at 70mm is f4, while the maximum aperture at 210mm is f5.6. So how is it possible for you to obtain f4 at 210mm? could you phrase your question differently? i'm afraid i don't understand it.
    my lens is AF 70-210mm f/4-5.6 D (it comes with a aperture ring)
    you are totally right to say that at 210mm it should be at f5.6; and i know that DSLR would not allow us to change the aperture on the aperture ring, it can only be set digitally. which by default, at 210mm it will be at f5.6.

    but when i mount the lens on a extension tube with no electronic contact from the lens to the body, i can shoot @ 210mm f4 because now i am using the setting on the aperture ring and not the digital setting. the same goes on my SLR which control the aperture through the aperture ring and not digitally, so at 210mm i can still leave the aperture ring at f4 for shooting.

    so i know by default, at 210mm it should be at f5.6 else it would be just a 70-210mm f4 lens. and from my trails on my dslr at the f5.6 and f4 @ 210mm the only diff i can notice is that at f4 it is more exposed which is correct! lol. so i want to know what is suppose to be the difference since the default is suppose to be f5.6 and not f4. because i will be shooting on slides and i foresee that i would occasionally forget to switch to f5.6 at 210mm, i want to know what is suppose to happen. more distortion? fade edges? or what effect i should be expecting for breaking the norm of the lens. thanks.

  5. #5
    Moderator Octarine's Avatar
    Join Date
    Jan 2008
    Location
    Pasir Ris
    Posts
    12,392

    Default Re: 70-210mm f4-5.6 -- shooting at f4@210mm

    The lens gives you a maximum aperture of f/5.6 @210mm due to it's construction. Read how aperture is defined. Please tell us a bit how you are shooting. Seems you are using Manual, otherwise you would not get any 'more exposed' shots because in any half-automatic mode the camera would adjust the shutter speed according metering result.
    EOS

  6. #6
    Member fmeeran's Avatar
    Join Date
    Nov 2010
    Location
    Clementi, Singapore
    Posts
    834

    Default Re: 70-210mm f4-5.6 -- shooting at f4@210mm

    Quote Originally Posted by rinford View Post
    my lens is AF 70-210mm f/4-5.6 D (it comes with a aperture ring)
    you are totally right to say that at 210mm it should be at f5.6; and i know that DSLR would not allow us to change the aperture on the aperture ring, it can only be set digitally. which by default, at 210mm it will be at f5.6.

    but when i mount the lens on a extension tube with no electronic contact from the lens to the body, i can shoot @ 210mm f4 because now i am using the setting on the aperture ring and not the digital setting. the same goes on my SLR which control the aperture through the aperture ring and not digitally, so at 210mm i can still leave the aperture ring at f4 for shooting.

    so i know by default, at 210mm it should be at f5.6 else it would be just a 70-210mm f4 lens. and from my trails on my dslr at the f5.6 and f4 @ 210mm the only diff i can notice is that at f4 it is more exposed which is correct! lol. so i want to know what is suppose to be the difference since the default is suppose to be f5.6 and not f4. because i will be shooting on slides and i foresee that i would occasionally forget to switch to f5.6 at 210mm, i want to know what is suppose to happen. more distortion? fade edges? or what effect i should be expecting for breaking the norm of the lens. thanks.
    Quote Originally Posted by Octarine View Post
    The lens gives you a maximum aperture of f/5.6 @210mm due to it's construction. Read how aperture is defined. Please tell us a bit how you are shooting. Seems you are using Manual, otherwise you would not get any 'more exposed' shots because in any half-automatic mode the camera would adjust the shutter speed according metering result.
    What Octarine said. Basically even if you manually turn the ring to f/4, because of the optical construction, the lens can only shoot at f/5.6 at 210mm. The aperture ring can't widen the physical constraints of the lens. So it's still f/5.6. I hope that made sense.
    Dxxxx | 35/1.8 | 50/1.8 | Tokina 28-70 | Panny G1 | 14-45 | 25/1.7
    My Flickr

  7. #7
    Senior Member ovaltinemilo's Avatar
    Join Date
    Sep 2009
    Location
    Sin jia Po lah
    Posts
    2,820

    Default Re: 70-210mm f4-5.6 -- shooting at f4@210mm

    Quote Originally Posted by rinford View Post
    hi,

    straight to the point.

    lens: 70-210mm f4-5.6 - with aperture ring

    i shot @ 210mm using f4 and 5.6 the only diff i see was that the @f4 it is more exposed (which is correct) but of cause it is a f4-5.6 lens so there has to be reason it should be f5.6 @ 210mm. so can someone enlighten me regarding this issue?

    ps. i am afraid that i forget to switch to f5.6 @210mm when i shoot on my slr. is there any issue like distortion, fade edges or whatever that is suppose to be happening?

    thanks.
    No matter what, you can only get f5.6 max @210mm even though your din stop down etc. It's alr f5.6 when you zoom the lens to 210mm.
    "is there any issue like distortion, fade edges or whatever that is suppose to be happening", all these have nothing to do with exposure..
    ...:::..::.Nikon.::.:::..
    RGB Metering & Focusing.

  8. #8

    Default Re: 70-210mm f4-5.6 -- shooting at f4@210mm

    hello Octarine and fmeeran. thank you for the reply. this is so super interesting. so i summarize that on the aperture ring when i set to f4, lens to 210mm, despite there is no change of size in the aperture blades, it has become f5.6 as it is the way the lens is constructed. after further playing with the lens, i notice that if i extend the lens to 210mm, when i change the aperture ring from f4 to f5.6, despite there is movement in the blades within, the change is not big enough to block the optic, meaning to say i still see a full circle within.

    the thing that is bothering me is that this is how i shoot yesterday.
    Camera: D90
    Lens: Nikon 70-210mm f/4-5.6 D + extension tube for macro (without electronic contact)
    Mode: Manual

    without extension tube


    with extension tube
    Shutter speed: 3sec
    ISO: 200
    Lens: @210mm (aperture ring set to f5.6)


    with extension tube
    Shutter speed: 3sec
    ISO: 200
    Lens: @210mm (aperture ring set to f4)


    despite there should be no change between f4 and f5.6 at 210mm, we can see the 3rd picture more exposed than 2nd pic. but my guess is that it is caused by the additional extension tube.

    can i assume that if i shoot on my nikon FE in aperture priority mode, when the lens is at 210mm and the aperture ring is at f4, i will under expose by 1 stop?

  9. #9
    Senior Member ovaltinemilo's Avatar
    Join Date
    Sep 2009
    Location
    Sin jia Po lah
    Posts
    2,820

    Default Re: 70-210mm f4-5.6 -- shooting at f4@210mm

    Quote Originally Posted by rinford View Post
    hello Octarine and fmeeran. thank you for the reply. this is so super interesting. so i summarize that on the aperture ring when i set to f4, lens to 210mm, despite there is no change of size in the aperture blades, it has become f5.6 as it is the way the lens is constructed. after further playing with the lens, i notice that if i extend the lens to 210mm, when i change the aperture ring from f4 to f5.6, despite there is movement in the blades within, the change is not big enough to block the optic, meaning to say i still see a full circle within.

    the thing that is bothering me is that this is how i shoot yesterday.
    Camera: D90
    Lens: Nikon 70-210mm f/4-5.6 D + extension tube for macro (without electronic contact)
    Mode: Manual

    without extension tube


    with extension tube
    Shutter speed: 3sec
    ISO: 200
    Lens: @210mm (aperture ring set to f5.6)


    with extension tube
    Shutter speed: 3sec
    ISO: 200
    Lens: @210mm (aperture ring set to f4)


    despite there should be no change between f4 and f5.6 at 210mm, we can see the 3rd picture more exposed than 2nd pic. but my guess is that it is caused by the additional extension tube.
    I have pondered upon this before.
    This is what I think:
    for the 2 shots with extension tube, the extension tube and lens extended gives the same length. The only thing that can make a difference to the amount of light is the aperture ring. Opening from f5.6 to f4 gives more light for exposure.

    Quote Originally Posted by rinford View Post
    can i assume that if i shoot on my nikon FE in aperture priority mode, when the lens is at 210mm and the aperture ring is at f4, i will under expose by 1 stop?
    If you do this, do check the shutter speed when you shoot at 210mm at "f4". I thimk the exposure is the same as at f5.6.

    Can try and post again?
    ...:::..::.Nikon.::.:::..
    RGB Metering & Focusing.

  10. #10
    Moderator Octarine's Avatar
    Join Date
    Jan 2008
    Location
    Pasir Ris
    Posts
    12,392

    Default Re: 70-210mm f4-5.6 -- shooting at f4@210mm

    Repeat your steps without extension tube, the lens properly connected to the cam. Curious what the results will be.
    EOS

  11. #11

    Default Re: 70-210mm f4-5.6 -- shooting at f4@210mm

    Quote Originally Posted by ovaltinemilo View Post
    If you do this, do check the shutter speed when you shoot at 210mm at "f4". I thimk the exposure is the same as at f5.6.
    i was quite puzzled by this issue but the exposure is indeed different @ the same speed. :S
    and shooting on a old SLR like FE which depend on the aperture ring to mechanically know which fstop it is at does make a different in the speed their metering comes out with.

  12. #12

    Default Re: 70-210mm f4-5.6 -- shooting at f4@210mm

    Quote Originally Posted by Octarine View Post
    Repeat your steps without extension tube, the lens properly connected to the cam. Curious what the results will be.
    i cant do it on digital as u know DSLR won't allow aperture size to be chosen by aperture ring. but i will try it out on my SLR and after the film is developed i will keep you posted with the result.

  13. #13
    Senior Member ovaltinemilo's Avatar
    Join Date
    Sep 2009
    Location
    Sin jia Po lah
    Posts
    2,820

    Default Re: 70-210mm f4-5.6 -- shooting at f4@210mm

    Quote Originally Posted by rinford View Post
    i cant do it on digital as u know DSLR won't allow aperture size to be chosen by aperture ring. but i will try it out on my SLR and after the film is developed i will keep you posted with the result.
    Pls post so. To what I understand, if you extend it to 210mm, the loss in light is the same as the aperture being closed to f5.6...so you would not really get a f4 at 210mm. This is due to physical construction of the lens. This is why I think the exposure should be same even if you shoot at 210mm "f4" and 210mm f5.6.

    Do correct if my understanding is incorrect.
    ...:::..::.Nikon.::.:::..
    RGB Metering & Focusing.

  14. #14
    Moderator Octarine's Avatar
    Join Date
    Jan 2008
    Location
    Pasir Ris
    Posts
    12,392

    Default Re: 70-210mm f4-5.6 -- shooting at f4@210mm

    Quote Originally Posted by rinford View Post
    i cant do it on digital as u know DSLR won't allow aperture size to be chosen by aperture ring. but i will try it out on my SLR and after the film is developed i will keep you posted with the result.
    In Manual mode any camera should accept manual lenses. Check your manual, should be mentioned somewhere. It's called step-down metering, the camera meters the light coming in, regardless what aperture is reported or not.
    EOS

Bookmarks

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •