F stops (Page 2): Very clear explanation of the F-stop designation on a lens.

Silverman Loc: Michigan

Kozan wrote:

The ones with one F-stop means it has a constant F-stop throughout the range. For instance, the Nikon 200-500mm F/5.6 has a constant F-stop all the way from 200mm through 500mm.

Other lenses that list two F-stops lists the F-stop at the shortest focal length, then the F-stop at the longest focal length. The F-stop of the lens changes depending on the focal length the lens is set to.

Hope that is clear.

Very clear explanation of the F-stop designation on a lens.

camerapapi Loc: Miami, Fl.

"Other lenses that list two F-stops lists the F-stop at the shortest focal length, then the F-stop at the longest focal length. The F-stop of the lens changes depending on the focal length the lens is set to."

Those lenses that list two f stops are called variable f stop lenses. If the maximum f stop is set and the lens is moved to different focal lengths the apertures will vary and the same goes if setting the minimal f stop. Any aperture in between when set will not make the aperture to change and in that respect they behave like a fixed aperture lens.

dsmeltz Loc: Philadelphia

camerapapi wrote:

"Other lenses that list two F-stops lists the... (show quote)

On a variable f stop zoom lens, if you are at the short end and set the f-stop to its widest (say 2.8) and then zoom in to the longest length, the f-stop will change to the higher number. And this change will be in steps as the focal length increases.

Lars Bogart Loc: Camano Isl., Wa., U.S.A.

Now THAT is Great INFORMATION !!!
Thank You !!

PHRubin Loc: Nashville TN USA

First: If a lens has more than one f stop listed, it is likely a zoom lens whose widest aperture varies as you zoom. Otherwise it is a fixed focal length lens that can be varied in aperture over that range.

A zoom lens with one aperture listed stays at that aperture at its widest over its focal length range.

Photocraig

FreddB wrote:

I thought I made a mistake once, but I was wrong.
😈😈😈😈😈😈😈😈😈😈😈😈😈😈😈😈😈😈😈😈😈😈😈😈😈😈😈😈😈

Not since 1959, for ME!

dsmeltz Loc: Philadelphia

FreddB wrote:

I thought I made a mistake once, but I was wrong.
😈😈😈😈😈😈😈😈😈😈😈😈😈😈😈😈😈😈😈😈😈😈😈😈😈😈😈😈😈

Photocraig wrote:

Not since 1959, for ME!

It was 1959 for me....

No, I meant 1958

[he is thrown over the edge into the ravine by an unseen force] AUUUUUUUUGGGH!

trapper1 Loc: Southside Virginia

Many thanks to all who posted responses. It will take me a while to assimilate all of this information and put it into practice but I am making some progress. Transitioning from a point-and-shoot to a Nikon 5600 DSLR at age of 84 is not the easiest task since there is a bewildering amount of new information to learn.

Kozan Loc: Trenton Tennessee

saxman71 wrote:

You're right of course. Another good reason why I should refrain from answering questions here.

Well, one does take a chance in answering questions. You run the risk of not giving enough information, as in my case, or giving the wrong information, as I have done in the past. The former, I don't care about. The latter is very embarrassing.

I usually answer with just enough information, but I be damned if i'm going to spend a lot of time with something the OP could look up with a search engine in the first place. I'll leave that to those who just want to show how smart they are.

JD750 Loc: SoCal

Kozan wrote:

The ones with one F-stop means it has a constant F-stop throughout the range. For instance, the Nikon 200-500mm F/5.6 has a constant F-stop all the way from 200mm through 500mm.

Other lenses that list two F-stops lists the F-stop at the shortest focal length, then the F-stop at the longest focal length. The F-stop of the lens changes depending on the focal length the lens is set to.

Hope that is clear.

Very good answer.

I will add that single aperture lenses are the preferred choice, they are faster, and tend to be of higher optical quality, but they cost more.

dsmeltz Loc: Philadelphia

Kozan wrote:

Well, one does take a chance in answering questions. You run the risk of not giving enough information, as in my case, or giving the wrong information, as I have done in the past. The former, I don't care about. The latter is very embarrassing.

I usually answer with just enough information, but I be damned if i'm going to spend a lot of time with something the OP could look up with a search engine in the first place. I'll leave that to those who just want to show how smart they are.

Often I find myself in the same position. However, it is usually because the OP has not really thought the question through. Many posts are too general and lack enough information on which to base a useful comment. In these cases, I try to ask a clarifying question. Unfortunately, in the rare instances that the OP actually provides more detail, the thread has already been hijacked by someone making statements about what they think the OP really needs to know.