Thats annoying

[TCR4x4]

My new Nikon 105mm f/2.8 macro lens has arived and just had a quick play in the garden. The first thing I noticed is that at close distances, the lens wont let you stop down the aperture to 2.8, instead it goes to something like 4.8. You can only get 2.8 at infinity.
I realise in order to acheive this close focussing the lens needs to extend inside the body, but couldnt they have done something so the camera still shows f/2.8, even if strictly speaking its not. I feel a bit cheated of those few stops.
To be honest they shouldnt market the lens as f/2.8 if in fact it isnt, but f2.8- 4.8.

Every other macro lens Ive had has always displayed f/2.8. Does this mean they were lying?

 

[ecniv]

Dont worry about it

Had the same with my 105mmD version

Its because the focal distance would be too small to be used...
At least thats what I was told

Makes sorta sense too...

Congrats on a great purchase, now go get yourself some cheap tubes too for even closer (but manual) pictures

 

[GRECIAN]

I nearly brought one of these before i noticed i was spening too much.
I am interested to read your findings but note the peak performance for this lens is reached between f/4 and f/5.6, seems strange though that you cant achieve F2.8 if you want to.

 

[Islander]

I bet you miss the EF 100mm L

 

[TCR4x4]

I bet you miss the EF 100mm L

Hmm, a little..

I now know its normal for this lens, but I cant understand why Nikon advertise it as a f/2.8 lens when it isnt.

Thankfully most macro stuff doesnt use f/2.8, but when you have paid £600 for an f/2.8 lens you should be able to use f/2.8 whenever you want.

 

[squishy]

nono, this is normal

effective aperture: set aperture + magnification ratio x set aperture

So if you set f/11 at infinity, you'll be effectively getting f/22 at 1:1.

Nikon's report the effective aperture, which gets slower at higher ratios with ANY macro lens (yes, your 100L did do this, just canon bodies don't report it, you'll just be getting two stops slower shutter speed at 1:1 than at infinity with the same aperture set on a canon body).

Personally I like the way canon bodies don't change the aperture they report, it makes things simpler, but I can see the advantage of it reporting the effective aperture.

 

[magicaxeman]

Meh, the Tamron SP90's better all round anyway..

 

[TCR4x4]

Meh, the Tamron SP90's better all round anyway..

Apart from the dubious build quality, stupid akward clutch and the fact it extends about 2 foot when focusing... :razz:

 

[HoppyUK]

nono, this is normal

<snip>

Yes. Strictly speaking, the f/number is only good at infinity focus. By the time you get down to 1:1, it is two stops lower (though 'focus breathing' usually reduces that a bit).

Nikon reports the new 'effective' f/number, Canon doesn't. But even more confusingly, even though the effective f/number might be f/4.5 or whatever, the depth of field will still relate to f/2.8... :shrug:

 

[jomike]

Meh, the Tamron SP90's better all round anyway..

My Tamron SP90 reports a max aperture of f/5.6 at 1:1. (Nikon fit).

 

[AndyB1976]

Sorry for jumping in here with a newbie question, outside Talk Basics;


Do zoom lenses also change or affect aperture (talking fixed aperture here), or is it soley a cause of focus then as described in the aforementioned macro prime at 1:1?

Also, what are fixed aperture zoom lenses doing or how are they differently engineered to retain a fixed aperture when zooming compared to variable apertures zoom lenses?



Andy

 

[TCR4x4]

My Tamron SP90 reports a max aperture of f/5.6 at 1:1. (Nikon fit).

The one I had reported f/2.8 on my D200, d90 and D700. So did the sigma f/2.8. Weird.

 

[Trig's]

I'm not gonna mention anything about the Sigma 150mm f2.8 macro that I recommended that you should've got (even less £'s) but hey it was your choice & you picked what you liked....

Will be checking the Nikon threads thou

 

[TCR4x4]

Its not that big of a deal, just a bit naughy on Nikons part.
Everything else seems spot on, although the weather was shocking today so havent had a chance to test it much.

 

[Davec223]

nono, this is normal

effective aperture: set aperture + magnification ratio x set aperture

So if you set f/11 at infinity, you'll be effectively getting f/22 at 1:1.

Nikon's report the effective aperture, which gets slower at higher ratios with ANY macro lens (yes, your 100L did do this, just canon bodies don't report it, you'll just be getting two stops slower shutter speed at 1:1 than at infinity with the same aperture set on a canon body).

Personally I like the way canon bodies don't change the aperture they report, it makes things simpler, but I can see the advantage of it reporting the effective aperture.

Its not that big of a deal, just a bit naughy on Nikons part.
Everything else seems spot on, although the weather was shocking today so havent had a chance to test it much.

I know all macro lenses do this, just because nikon choice to report, I do not see them as being naughty, if anything I would say it is naughty of the other manufactures, although I can see why they do it, as it stops questions and threads like this, and I hasten to add that I am not having a go as I rang the shop where I got mine complaining that something was amiss with it, only to have it all explained to me.

 

[HoppyUK]

Its not that big of a deal, just a bit naughy on Nikons part.
Everything else seems spot on, although the weather was shocking today so havent had a chance to test it much.

It's not naughty, it's Nikon being honest. All macros do it.

Do you want to know the effective aperture, for exposure (Nikon) or the effective f/number, for depth of field (Canon)? Arguably the former is more useful.

 

[squishy]

It's not naughty, it's Nikon being honest. All macros do it.

Do you want to know the effective aperture, for exposure (Nikon) or the effective f/number, for depth of field (Canon)? Arguably the former is more useful.

Doesn't make any difference. Canons compensate for the loss of light the same as nikons, they just don't report an aperture change. Doesn't really make any difference. If find it easier that I can set the aperture in actual terms and the camera compensates for it automatically, I suppose if I did more manually exposed macro with a light meter it might come in handy to have the effective aperture reported, but I've never owned or used a light meter, and don't know of any macro photographers who do. I don't want to set f/8 at 1:1, only to discover I've actually been taking pictures at f/4 with DoF too tiny to be useful!

 

[Dutchie]

I've never noticed this. But then again, I don't use the F2.8 when doing macro

 

[squishy]

I've never noticed this. But then again, I don't use the F2.8 when doing macro

You don't have to. It applies to the entire aperture range. f/11 effectively becomes f/22 (in exposure terms) at 1:1.

 

[jomike]

To see this working, and your lens has a manual aperture ring, you can take the macro lens off the camera, set the aperture to 2.8 and set focus to infinity. Look through the lens and focus towards 1:1. You can see the aperture getting smaller although the aperture blades themselves do not move.

Whether the lens reports actual aperture or effective aperture is a moot point really as shooting below f/8 at 1:1 is not really practical because of DOF issues. I usually shoot at f/10 - f/16 and then still sometimes focus stack to get any useful DOF.

 

[TCR4x4]

To see this working, and your lens has a manual aperture ring, you can take the macro lens off the camera, set the aperture to 2.8 and set focus to infinity. Look through the lens and focus towards 1:1. You can see the aperture getting smaller although the aperture blades themselves do not move.

Whether the lens reports actual aperture or effective aperture is a moot point really as shooting below f/8 at 1:1 is not really practical because of DOF issues. I usually shoot at f/10 - f/16 and then still sometimes focus stack to get any useful DOF.

Its the latest VR version so doesnt have an aperture ring. I understand why it does it now, and Im not fussed, its just an OCD type thing that it wont let me choose f/2.8 even though in reality is I cant see it on the screen and that annoys me.

I rarely shoot below f/8 for proper macro stuff, but even focused at 10 feet it still only goes to f/3. Thankfully the high ISO of the D700 means I can leave it at f/5.6 or higher most of the time anyway and still get the shutter speed I need.