The effect of front element size

[RevvinKevin]

What effect, if any, does the front lens element size have on exposure?

All of my lenses have a 58mm front lens element. I believe the L series have a 72mm lens.

If I were to set my camera at 1/125, f8, iso200 for a given scene would a person (using the same body, therefore sensor sensitivity) have exactly the same setup or would something change due to the front element size.?

[djguk47]

Re: The effect of front element size

Kevin, unfortunately your assumption about "L" lenses is incorrect eg... 100-400 is 77mm, 70-200 f2.8 IS is 77mm, 24-105 f4 is 77mm.
Larger front element size = more light = ability to shoot at a lower ISO in low light.

Someone will now come along with all the technical "stuff" about what I have said....

David

[briansquibb]

Re: The effect of front element size

My L lens have 67mm, 72mm, 77mm, 82mm and something too big for my ruler

[Trevoreast]

Re: The effect of front element size

If I were to set my camera at 1/125, f8, iso200 for a given scene would a person (using the same body, therefore sensor sensitivity) have exactly the same setup or would something change due to the front element size.?

The short answer devoid of any “nerd speak” is no.
If it had any impact, you'd have to have a whole new set of settings on a hand held light meters for starters.

Is a 50mm 1.4 with a 58mm filter thread faster than a 24-105 F4L with a 77mm filter thread ? - yes it is

Trev

[RevvinKevin]

Re: The effect of front element size

There's a couple of reasons I ask the question.

I have a Canon 75-300 f4-5.6 (non IS) which I cannot hand hold successfully for toffees at anything above 200mm. To achieve anything resembling a decent shutter speed I have to open up fully and push the ISO up. Now, the next problem is that my 1000D doesn't like high ISOs and shows lots of noise. So I'm wondering if I should look to upgrade the lens to an L (70-200), the body (for something with good high ISO performance, 5Dmk11?) or both in which case I shan't be taking many photographs as I'll be recovering from surgery after selling my vital organs to finance the upgrade.

[briansquibb]

Re: The effect of front element size

What iso are we talking about here? I take a lot of pictures with the 70-300L which has the same f no as yours

[RevvinKevin]

Re: The effect of front element size

Brian, noise becomes noticeable at 400, very noticeable at 800 and downright horrible at 1600. I've used the NR correction in DPP which softens the image.

It's not often I use the lens because of this issue. To be honest I haven't printed anything out to see if the high ISO noise is visible at A4, it might just be that I'm blowing it up too much on screen (iMac has a very good screen) and the lower resolution of printing would be ok.

[raymon]

Re: The effect of front element size

Hi Kevin, I am a novice so tounge firmly in cheek, I think what you must remember that with a crop sensor shooting at FL 200mm plus it is effectively FL 360mm plus, without IS you are probably going to struggle hand held without being in excess of a shutter speed of 300-400, I think you may be expecting too much of yourself and your equipment, maybe a tri or monopod may be a cheaper option, you dont mention what your shooting though.

Ray

[MX5]

Re: The effect of front element size

If you are using a none-IS lens at say 200mm on a crop sensor body then you need at least 1/320 second for handholding. That also assumes you have the technique right ... breathing, posture etc. When the light drops I look for something to support the camera (fence, wall, etc.) or support me (again fence, wall, tree etc.). But if you are open wide (say f/4) and your ISO comfort limit is ISO 400 then that determines the lowest light you can safely hand hold in. IS will help. A camera with better high ISO noise will help. A monopod/tripod/Pod will also help. But practice your technique (I'm told it’s akin to firing a rifle by a photographer friend who also is a (legal) gun user).