Is f/2.8 to f/8.0 a really low range?

workaccount

I'm just reading understanding exposure as I'm trying to develop a better interest in photography before buying a better camera.

Today I was testing out aperture with my Powershot S1 IS. I can notice differences between the max and low aperture alright but it's not massive at all which is a little disapointing. I would like to be able to see the big differences in my own photos like the ones the author has published. Some of his examples are between f/5.6 and f/32 for example.

Anyways I was thinking I would get a way larger spectrum when the time comes to upgrade to an SLR with a lens or two. I just had a quick look on B&H and am surprised to see that the lenses (some very expensive) have even less range.

http://www.bhphotovideo.com/c/product/12059-USA/Canon_2565A003_100_300mm_f_4_5_5_6_USM_Autofocus.html
http://www.bhphotovideo.com/c/product/162616-GREY/Canon_2577A002AA_100_400mm_f_4_5_5_6L_IS_USM.html

Am I looking at the wrong lenses or something as I've just looked through the first two pages of Canon lenses and the largest aperture range seems to be on that second lens linked above which is only f/4.5 to f/5.6.

Dodgykeeper

The numbers mean it is the largest aperture available, 4.5 - 5.6 depending on where you are with the zoom! They will all go up to f22

Morrisseeee

This applies to zoom lenses, ie. 100mm @ f4.5 is the largest aperature & also 300mm @ f5.6 is the largest aperature.
Note: f1 is the largest aperature, but not used, f1.2 is about the biggest you will see. So if a lens has a largest aperature of f4.5 @ 100mm then it is considered a SLOW lens, ie. not letting in much light, ie. your shutter speed is going to have to be slow hense blur in your pictures of moving objects, unless you up the value of your ISO setting, but thats another story !

AnCatDubh

Darn it - you've just reminded me that I had intended to reread "understanding exposure" over Christmas but i've left it behind me! It is a very fine read indeed.

Anyway as to your query and in addition to what the users above have said there are a number of factors beyond the aperture range which will effect what effect you will see. I think you may be expecting a greater differential in terms of the depth of field and resulting bokeh that would be on your image.

If this is so then remember that your depth of field and resulting bokeh is actually influenced by a number of things including - the size of your camera's sensor, distance to subject, the focal length being used, and of course the f-stop.

When I actively used my Fuji bridge I found it difficult to control anything other than everything very much in focus to everything more or less in focus - I then switched to DSLR and such issues just went away. It is soooooo much easier with a DSLR. Having said that it is possible. Once you get to the lower of the aperture range on your canon try getting closer to your subject and see what effect that has on the background - Use your feet rather than your head. You should get better bokeh the closer you get to the subject. Same works in the DSLR world only the DSLR sensors are larger and are better engineered towards being able to creatively use manual controls with better quality optics available.

I found myself getting frustrated by the Fuji bridge in trying to achieve some of the creative side of photography (although I still love that old Fuji bridge - still take it out every so often for all its quirks).

I found it useful to use a DOF calculator. You could do a bit of study over here if you like.

Hope that helps.

sheesh

must be the time of year


here is a recent thread on the same topic