Canon 24-105 f/4 L on 1.6 crop cameras and lens hood, filters

Doug McDonald wrote:

I just bought one of these Canon 24-105 f/4 L lenses for my 30D.
It's a great, sharp lens.

However. It comes with a nice petal lens hood. BUT ... this clearly
is a hood for full frame cameras. Are there hoods for it specially
for the 1.6 crop cameras? They could be somewhat more effective since
they need cover a smaller field.

Yes that has occurred to me. I've never heard of 'digital lens shades'
though.


And that brings up filters. I was all ready to order up a 77mm filter
when I thought ... why not try a 58mm filter? So I did, just holding
it in front of the lens looking through the viewfinder. I saw no
vignetting at all. Of course, this is not a good test since the viewfinder
may not use the whole field or the whole aperture. I will experiment with
a proper stepdown setup and 55 and 52 mm filter. But ... does anybody
have any experience in this? A stepdown ring or two is a lot cheaper than
a 77 mm polarizer, and will of course also reduce flare.

Ha, well there's your lens shade in the step-down ring.

On Mon, 26 Mar 2007 17:01:50 -0600, Doug McDonald
wrote:

I just bought one of these Canon 24-105 f/4 L lenses for my 30D.
It's a great, sharp lens.

However. It comes with a nice petal lens hood. BUT ... this clearly
is a hood for full frame cameras. Are there hoods for it specially
for the 1.6 crop cameras? They could be somewhat more effective since
they need cover a smaller field.

Get one of the collapsible rubber lens hoods. The right ones can be
set into two and more positions making them more effective for both
the short and long settings of your zoom. I have the Hoya 77mm and
find it very useful with my 17-55mm/2.8.

And that brings up filters. I was all ready to order up a 77mm filter
when I thought ... why not try a 58mm filter? So I did, just holding
it in front of the lens looking through the viewfinder. I saw no
vignetting at all. Of course, this is not a good test since the viewfinder
may not use the whole field or the whole aperture. I will experiment with
a proper stepdown setup and 55 and 52 mm filter. But ... does anybody
have any experience in this? A stepdown ring or two is a lot cheaper than
a 77 mm polarizer, and will of course also reduce flare.

I don't have this lens, but I would find it hard to believe that Canon
would put such large front elements on this lens and then not make use
of that vitreous real estate. So almost for sure you will need to
spend big money on 77mm filters... just my guess.

KS

Doug McDonald wrote:
I just bought one of these Canon 24-105 f/4 L lenses for my 30D.
It's a great, sharp lens.

However. It comes with a nice petal lens hood. BUT ... this clearly
is a hood for full frame cameras. Are there hoods for it specially
for the 1.6 crop cameras? They could be somewhat more effective since
they need cover a smaller field.

And that brings up filters. I was all ready to order up a 77mm filter
when I thought ... why not try a 58mm filter? So I did, just holding
it in front of the lens looking through the viewfinder. I saw no
vignetting at all. Of course, this is not a good test since the viewfinder
may not use the whole field or the whole aperture. I will experiment with
a proper stepdown setup and 55 and 52 mm filter. But ... does anybody
have any experience in this? A stepdown ring or two is a lot cheaper than
a 77 mm polarizer, and will of course also reduce flare.

Doug McDonald

The step down ring will vignette at wide apertures, but you might get
away with it at smaller apertures, say f/8 or f/11, and the long end of
the zoom. You probably won't at f4 or at the short end.

Colin D.

--
Posted via a free Usenet account from http://www.teranews.com

I just bought one of these Canon 24-105 f/4 L lenses for my 30D.
It's a great, sharp lens.

However. It comes with a nice petal lens hood. BUT ... this clearly
is a hood for full frame cameras. Are there hoods for it specially
for the 1.6 crop cameras? They could be somewhat more effective since
they need cover a smaller field.

And that brings up filters. I was all ready to order up a 77mm filter
when I thought ... why not try a 58mm filter? So I did, just holding
it in front of the lens looking through the viewfinder. I saw no
vignetting at all. Of course, this is not a good test since the viewfinder
may not use the whole field or the whole aperture. I will experiment with
a proper stepdown setup and 55 and 52 mm filter. But ... does anybody
have any experience in this? A stepdown ring or two is a lot cheaper than
a 77 mm polarizer, and will of course also reduce flare.

Doug McDonald

You can pay for the lens but you cheap out on the filter??? I have ONE
77mm polariser which fits many of my lenses with the same threads. I have a
step down ring from 77mm to 67mm to use it on my 70-200 f4 which has a
smaller diameter.

Jean



"Doug McDonald" a écrit dans le message de
...
I just bought one of these Canon 24-105 f/4 L lenses for my 30D.
It's a great, sharp lens.

However. It comes with a nice petal lens hood. BUT ... this clearly
is a hood for full frame cameras. Are there hoods for it specially
for the 1.6 crop cameras? They could be somewhat more effective since
they need cover a smaller field.

And that brings up filters. I was all ready to order up a 77mm filter
when I thought ... why not try a 58mm filter? So I did, just holding
it in front of the lens looking through the viewfinder. I saw no
vignetting at all. Of course, this is not a good test since the viewfinder
may not use the whole field or the whole aperture. I will experiment with
a proper stepdown setup and 55 and 52 mm filter. But ... does anybody
have any experience in this? A stepdown ring or two is a lot cheaper than
a 77 mm polarizer, and will of course also reduce flare.

Doug McDonald

King Sardon wrote:

I don't have this lens, but I would find it hard to believe that Canon
would put such large front elements on this lens and then not make use
of that vitreous real estate.

But that would be on a full-frame camera. My 30D is seriously cropped,
and hence at wide angle it does not use anywhere near the full lens front.

someone else wrote:

"You can pay for the lens but you cheap out on the filter??? I have ONE
77mm polariser which fits many of my lenses with the same threads. I have a
step down ring from 77mm to 67mm to use it on my 70-200 f4 which has a
smaller diameter."


I'm not trying to cheap out. I'll buy a first rate 58 mm filter.
If it does not vignette, so be it. It seems to not be vignetting at all.

And, as noted, the step down ring will reduce flare.

Doug McDonald

On Tue, 27 Mar 2007 15:26:48 -0600, Doug McDonald
wrote:

King Sardon wrote:

I don't have this lens, but I would find it hard to believe that Canon
would put such large front elements on this lens and then not make use
of that vitreous real estate.

But that would be on a full-frame camera. My 30D is seriously cropped,
and hence at wide angle it does not use anywhere near the full lens front.

Yes, good point.

And yes, a step-down would work like a kind of lens shade and reduce
flare.

KS

Doug McDonald wrote:
I just bought one of these Canon 24-105 f/4 L lenses for my 30D.
It's a great, sharp lens.

However. It comes with a nice petal lens hood. BUT ... this clearly
is a hood for full frame cameras. Are there hoods for it specially
for the 1.6 crop cameras? They could be somewhat more effective since
they need cover a smaller field.

And that brings up filters. I was all ready to order up a 77mm filter
when I thought ... why not try a 58mm filter? So I did, just holding
it in front of the lens looking through the viewfinder. I saw no
vignetting at all. Of course, this is not a good test since the viewfinder
may not use the whole field or the whole aperture. I will experiment with
a proper stepdown setup and 55 and 52 mm filter. But ... does anybody
have any experience in this? A stepdown ring or two is a lot cheaper than
a 77 mm polarizer, and will of course also reduce flare.

Doug McDonald

Is there any sharpness difference at f4 and f8?
I have the cheaper 24-205 non L and it is only
good at 5.6 and above.

In article t Paul Furman writes:
$Doug McDonald wrote:
$ However. It comes with a nice petal lens hood. BUT ... this clearly
$ is a hood for full frame cameras. Are there hoods for it specially
$ for the 1.6 crop cameras? They could be somewhat more effective since
$ they need cover a smaller field.
$
$Yes that has occurred to me. I've never heard of 'digital lens shades'
$though.

Canon has one official lens hood per lens. If it's a full-frame
lens, then it's a lens hood designed for that lens' angle of view on a
full-frame body. If it's an EF-S (1.6-crop only) lens, then it's a
lens hood designed for that lens' angle of view on a 1.6-crop body.
So there's no official solution if you want a narrower lens hood
to use a full-frame lens on a cropped-sensor body.

That said, there are a number of known substitutions for this sort
of thing; in fact, the 24-105's hood is one of the well-known alternate
hoods for the widely-used 17-40 on a 1.6-crop body. I know, that doesn't
help you. The table at http://www.burren.cx/photo/alternate_hoods.html
lists an alternative hood for the 24-105, but it's likely only a
bit better than the stock hood on a 1.6-crop body, as it's for a
28mm-equivalent field of view. (It's the hood for the 17-55, but
as that's an EF-S lens, the hood is designed for a 1.6-crop body.)
--
Stephen M. Dunn
---------------- http://www.stevedunn.ca/ ----------------
------------------------------------------------------------------
Say hi to my cat -- http://www.stevedunn.ca/photos/toby/

In article Doug McDonald writes:
$King Sardon wrote:
$ I don't have this lens, but I would find it hard to believe that Canon
$ would put such large front elements on this lens and then not make use
$ of that vitreous real estate.
$
$But that would be on a full-frame camera. My 30D is seriously cropped,
$and hence at wide angle it does not use anywhere near the full lens front.

This is not necessarily the case. Light rays don't take a straight
path through the lens, and it's not true that light rays passing through
the middle of the front element strike only the middle of the film/sensor
or that light rays passing through the outer edges of the front element
strike only the outer edges of the film/sensor.

It is likely that the use of a substantially smaller filter will
cause some vignetting even on a 1.6-crop body. You'd have to test it
at a variety of apertures and focal lengths (since the effect will
vary with both of these settings) to find out if it's enough to be a
concern to you.
--
Stephen M. Dunn
---------------- http://www.stevedunn.ca/ ----------------
------------------------------------------------------------------
Say hi to my cat -- http://www.stevedunn.ca/photos/toby/