MM Setting of Lens: Zoom lenses, as all know, have MM settings on the barrel. Is there any way, before taking the picture to ascertain what the MM setting is when the zoom is set...

BboH Loc: s of 2/21, Ellicott City, MD

Zoom lenses, as all know, have MM settings on the barrel.

Is there any way, before taking the picture to ascertain what the MM setting is when the zoom is set between 2 of the markings on the barrel? I have searched and cannot find a way to do so (the EXIF data created when the image is taken shows the MM, but that's after the fact) - figured maybe there is a way that I can't find, hope so but...

I'm using Nikon's D810 and D7100 and various Nikon lenses.
Thanks

TucsonCoyote Loc: Tucson AZ

Good point, you could use your own markings on the lenses !?

BboH Loc: s of 2/21, Ellicott City, MD

TucsonCoyote wrote:

Good point, you could use your own markings on the lenses !?

Likely will have to. With the exception of 2 - the 60 and 85mm's all other lenses have at least 1 setting that's common to all. Hoping maybe to avoid having to guess, snap, look, and guess again to adjust.

davidrb Loc: Half way there on the 45th Parallel

BboH wrote:

Zoom lenses, as all know, have MM settings on the barrel.

Is there any way, before taking the picture to ascertain what the MM setting is when the zoom is set between 2 of the markings on the barrel? I have searched and cannot find a way to do so (the EXIF data created when the image is taken shows the MM, but that's after the fact) - figured maybe there is a way that I can't find, hope so but...

I'm using Nikon's D810 and D7100 and various Nikon lenses.
Thanks

When I asked the fotocon @ Canon.com why no zoomie showed the focal length in the view finder the response was: "Nobody ever asked us for it." They went on to explain that none had ever really asked! I have known many folks who asked others about it, but apparently no one has ever told the manufacturers that users want it. Sounds weird.

Wahawk Loc: NE IA

What difference does it make as long as you can get the picture you want?? The focal length range of a zoom gives you an idea of 'what' you can shoot, and at what approximate range. The exact focal length is immaterial to me. I really don't care what the "mm" is as long as I get the picture I want.

RWR Loc: La Mesa, CA

BboH wrote:

Zoom lenses, as all know, have MM settings on the barrel.

Is there any way, before taking the picture to ascertain what the MM setting is when the zoom is set between 2 of the markings on the barrel? I have searched and cannot find a way to do so (the EXIF data created when the image is taken shows the MM, but that's after the fact) - figured maybe there is a way that I can't find, hope so but...

I'm using Nikon's D810 and D7100 and various Nikon lenses.
Thanks

Interesting question, one I've never heard asked. May I ask why you wish to know the exact focal length before the exposure? The only way I can suggest is to set the lens between marked lengths and run some test shots, noting the actual length set.

CaptainC Loc: Colorado, south of Denver

Been doing this for 50+ years and never wondered or cared. All that matters is what you see in the finder.So I just wonder why anyone would care.

Not a criticism - but why do you care?

davidrb Loc: Half way there on the 45th Parallel

CaptainC wrote:

Been doing this for 50+ years and never wondered or cared. All that matters is what you see in the finder.So I just wonder why anyone would care.

Not a criticism - but why do you care?

Captain, in your 50+ years you have seen the acceptance of zoom lenses, have you not? I know that 40 years ago when I bought my first SLR no one would even think of using a zoom. Now, maybe things are different? In all the banter over the pros and cons of primes and zooms the chief reason for using zooms now is that "they are equal to primes in quality." How do you know that a zoom is as good as a prime if you can not set the zoom to match?

Not a criticism - why do you question another photographer's effort in creativity?

CaptainC Loc: Colorado, south of Denver

davidrb wrote:

Captain, in your 50+ years you have seen the accep... (show quote)

I am not questioning creativity at all. This is not a creativity question it is a technical one. I can answer this for you - the professional-level zooms (constant aperture 2.8) are as good as primes for all practical purposes. Any difference is a distinction without a difference.

On the other hand, the primes WILL outperform the less expensive variable aperture zooms with extreme zoom ranges. There is a reason the good zooms are 2X and 3X, not 10x or more.

So there you go - now spend your time taking pictures with all the time you have saved.

You must be an engineer. :-) That is STILL not a criticism.

UtahBob Loc: Southern NJ

CaptainC wrote:

Been doing this for 50+ years and never wondered or cared. All that matters is what you see in the finder.So I just wonder why anyone would care.

Not a criticism - but why do you care?

I can see perhaps the case where you wish to shoot a panorama (an equirectangular for instance) and you've planned to shoot it at a particular mm to achieve either a certain image size or shots to take around on a row(s). Zooms will often have a changing no parallax point so you might want to identify a mm setting and the associated mount point on the pano head. In either case, I'd be marking the barrel appropriately.

I can see this being a concern with a super wide angle zoom used for interior sphericals where close objects require a good level of precision to avoid parallax and you would want repeatability on the zoom setting if not at the max or min.

Probably not the reason the OP is asking but one reason I might want to know or be able to repeat the setting.

CaptainC Loc: Colorado, south of Denver

UtahBob wrote:

I can see perhaps the case where you wish to shoot... (show quote)

Makes sense.

lighthouse Loc: No Fixed Abode

UtahBob wrote:

I can see perhaps the case where you wish to shoot... (show quote)

Yes, the parallax issue could make sense but it would not be MM specific, it would be very lens specific only.
It would only apply at that setting for that lens.
Different zooms are different lengths and have different internal and external movements.
EG The parallax point will be different at 90mm for a 24-105, vs 70-300, vs 70-200 etc.
And then there are lenses that change length during zoom and those that don't.
And some lenses focus breathe and some don't, or have differeing levels of it.

UtahBob Loc: Southern NJ

lighthouse wrote:

Yes, the parallax issue could make sense but it would not be MM specific, it would be very lens specific only.
It would only apply at that setting for that lens.

Sure, but for a specific lens the non parallax point is a certain point for a specific MM setting so it is a specific MM.

lighthouse wrote:

Different zooms are different lengths and have different internal and external movements.
EG The parallax point will be different at 90mm for a 24-105, vs 70-300, vs 70-200 etc.

Sure.

lighthouse wrote:

And then there are lenses that change length during zoom and those that don't.
And some lenses focus breathe and some don't, or have differeing levels of it.

And some are white and some are black ...

davidrb Loc: Half way there on the 45th Parallel

CaptainC wrote:

I am not questioning creativity at all. This is no... (show quote)

No, it is NOT criticism, buy, it IS the funniest thing I have read in ages! The closest I ever got to being an engineer was the Christmas I got a new Lionel locomotive :lol: My answer to this is actually found in another post where a user explains his reason for wanting to know this info. I know how confusing it can be to read and follow some of theses threads.

Seriously, and the Canon techs have agreed with this part, the focal length of a zoom is part of the EXIF. Why can not the engineers put that data in the view finder? They put everything else in there. This is simply digital signals that designers possibly could provide, IF they were asked to do so. And remember this; photography is a game of numbers! So why NOT provide the info ? The lack of this info led me to go away from zooms and stick to primes. I want to know exactly where I am in relation to the image subject. That ain't an engineer, that's the pilot! :lol: :lol: :lol:

UtahBob Loc: Southern NJ

davidrb wrote:

The lack of this info led me to go away from zooms and stick to primes. I want to know exactly where I am in relation to the image subject.

Would you mind expanding your thoughts - I'm missing what you are getting at or perhaps your subjects are very different than mine. Thanks.