Created: 2018.11.01
Many years ago I wrote an article
Many years ago I wrote an article
https://madmanpierre.com//personal-comments/canon-20d-digital-camera
on the Canon 20D camera I owned at the time. (Actually I still own that 2004 camera and still use it regularly - it is still WAY better than my cell phone for so many things. I'll have to write an article some day about why cell phone cameras have NOT gotten rid of the need for 'real' digital cameras.) Update 2019: I did write that article:
and I'mstill using my 20D camera as one of my 3 main 'real' cameras.
When talking to one of my daughters recently I realized that, while in 2004, my comments were specific to the Canon 20D camera and a very small number of other cameras of the day, today they are relevant to probably 90% of DSLR cameras.
It includes a chart of lens 'sizes'. If you have a DSLR that is NOT full frame, that chart is very accurate for your camera too.
Here is my 'modern' summary:
Most DSLR cameras have a 'small' sensor size, around APS-C, a size of film Kodak briefly sold while trying to not go bankrupt. Indeed almost all of the 'small sensor' DSLRs claim they are APS-C even though they are slightly larger or slightly smaller. And to be fair - the difference usually is not relevant in practical terms.
This means it is very hard to get a truly wide angle lens for your DSLR (if you have a full frame sensor then - no problem.) There are more details in the old blog, but what happened is that photographers are used to concepts like "an 18mm is a very wide angle lens," a "50mm is normal" a "80 is portrait". But when you put those same lenses on an APS-C sensor sized DSLR, they effectively change to the equivalent of a number that is about 1.6x's 'longer'.
- a very wide angle lens, say 18mm put on an APS-C DSLR becomes what we would have called 'somewhat wide angle'
- a 'moderately wide angle lens, say 30mm, put on a APS-C becomes what we historically called 'normal'
- a 'normal' 50mm plus or minus lens used on an APS-C DSLR becomes what photographers call a 'portrait' lens (aka about 80mm)
- a 'portrait' 80mm plus or minus becomes a 'moderately telephoto' lens
- a 200mm telephoto lens becomes a 'very telephoto' lens
- a 300mm 'very telephoto' lens becomes what I would call a 'monster' lens (about 460mm) - you need a tripod or very good image stabilization.
For more details, go read my old 2004 article. Everything in it is relevant today to all APS-C DSLR cameras. Funny how perspective changes through the years! What was 'revolutionary' and 'important differences' then are 'yeah, that's what everyone is doing' today.
Note: if you own a 'full frame' DSLR, you already know that my comments above do NOT apply to you, and you stopped reading long before you got to 'this' paragraph because you already knew all this technical stuff.
https://madmanpierre.com/personal-comments/canon-20d-digital-camera
On an interesting side note: no cell phones have 'telephoto' lenses - even if they (Pixel, Samsung, Apple) claim they do. All of them are wide angle. The 'most' telephoto as of October 2018 is actually quite wide angle. (Update Nov 2019: the newest Pixel's so called 'telephoto' is almost 'normal', the spec works out to 46mm as a 35mm film equivalent) so that fits within the range of 'normal' finally, not 'wide angle.'
Note, sorry that '35mm film' is used as the standard. And the 35mm for film size has no relationship (well not in a way that is obvious) to the mm size of the lens. So a 35mm lens on a 35mm 'full frame' sensor size camera is a wide angle lens. But a 35mm lens on an APS-C sensor size camera is a 'normal' or slightly towards portrait.