«

StarStruck wrote:

>> If I point the camera towards the sun would I be able to view
>> sunspots without a White-light filter or H-alpha (H-A) filter?
>>
>
> You really need to study up on how an H-alpha filter is used and what
> it is actually used for before you ask such a comment.

Have a corona on me.






Rita

RichA wrote:

>> If I point the camera towards the sun would I be able to view
>> sunspots without a White-light filter or H-alpha (H-A) filter?
>
> Concentrate the light from the unfiltered sun with a lens onto the
> sensor and KISS it goodby.

I'm just trying to find a valid justification for Live View, that's all. So
far it's not happening. I wonder if I can get Canon to remove it from my Mk
III and get a $25 rebate?





Rita

"Rita Ä Berkowitz" <ritaberk2O04 @aol.com> wrote in message
news:...
> William Graham wrote:
>
>> Actually, you can use a pinhole in a black card, and "project" the
>> sun's image on a white plane, or a projector screen, and then take
>> the shot that way.....You can use this technique for eclipses,
>> too.....
>
> Yep, that's a neat way of doing it. Seems like Live View was invented
> centuries ago.
>
>
>
>
>
>
> Rita
>
>
We did it once in the control room where I worked....We had a darkened room
anyway, so we just drilled a hole in the roof and projected a huge image on
a table top......Not too far from that same location was the Stanford solar
observatory....They had an optical system that projected the sun onto a
hemispherical table.....It made a fantastic image that was about three feet
across.....You could see solar flares, and sunspots.......They had an
optical system that would track the sun across the sky for about three hours
every afternoon......

Rita Ä Berkowitz wrote:
> RichA wrote:
>
>>> If I point the camera towards the sun would I be able to view
>>> sunspots without a White-light filter or H-alpha (H-A) filter?
>>
>> Concentrate the light from the unfiltered sun with a lens onto the
>> sensor and KISS it goodby.
>
> I'm just trying to find a valid justification for Live View, that's
> all. So
> far it's not happening. I wonder if I can get Canon to remove it from
> my Mk
> III and get a $25 rebate?
>
>
Shooting using an ultra-wide lens where you need to get down
low on wet ground to see through the viewfinder to compose a
shot including foreground objects.
Yeah - you could wear waterproof leggings, or carry a mat to
crawl on, but if liveview was a $25 option, I'd take it any day.

Of course with the weird oddball sensor size IdIII,
ultra-wide isn't possible, so YMMV.

On Mon, 10 Sep 2007 17:44:55 -0400, Rita Ä Berkowitz <ritaberk2O04 @aol.com>
wrote:

>RichA wrote:
>
>>> If I point the camera towards the sun would I be able to view
>>> sunspots without a White-light filter or H-alpha (H-A) filter?
>>
>> Concentrate the light from the unfiltered sun with a lens onto the
>> sensor and KISS it goodby.
>
>I'm just trying to find a valid justification for Live View, that's all.
>

Oh, you're one of those <eye-roll>. Someone who has never obtained any
experience with all the advanced capabilities of the P&S cameras that far
surpass anything that any DSLR can do.

How about this then:

When taking images of waterfalls or rapids you can dial-in the slow shutter
speed you need to see how much you are blurring the water, seeing it happen in
real-time in the EVF. Instead of just hoping it'll be right. You can see the
exact effect you will get on your resulting image, instead of taking a photo,
checking it, resetting to a slower shutter speed, taking another, checking it,
resetting it ... ooops too late, that wading-bird in the scene that made it the
most perfect award-winning photo was scared off by the gawdawful noises that
your DSLR's shutter and slapping mirror were making. Or if you want to dial-in
the exact amount of motion blur you want in a batter's swing, or a bird's
wing-beat, or the props of a plane. You will see the effect as you compose your
shot and be able to capture exactly what you want.

Unlike every other DSLR on earth with only an OVF where none of this is ever
possible, but it IS possible on nearly every P&S camera in existence with an
LCD/EVF.

Get your head out of your DSLR ass, it's been stuck up there so long with your
ancient technology you can't even see the light.

Rita Ä Berkowitz wrote:
> RichA wrote:
>
>>> If I point the camera towards the sun would I be able to view
>>> sunspots without a White-light filter or H-alpha (H-A) filter?
>>
>> Concentrate the light from the unfiltered sun with a lens onto the
>> sensor and KISS it goodby.
>
> I'm just trying to find a valid justification for Live View, that's
> all. So
> far it's not happening. I wonder if I can get Canon to remove it from
> my Mk
> III and get a $25 rebate?
>
>
>
>
>
> Rita
>

If the live view on the MkIII is the same thing (or similar) as the 20DA
came with then slap on a piece of Baader film in front of the 400mm lens
and you will be able to see a fair bit of detail in the sunspots as well
as be able to count them.
The sun is 0.5 of a degree in diameter so from your FOV of the 400 you
should get an idea of the pixel resolution for the solar image.

George

Rita Ä Berkowitz wrote:
> If I point the camera towards the sun would I be able to view sunspots
> without a White-light filter or H-alpha (H-A) filter?

You're very likely to fry your eye and the camera sensor but if you're
interested in astronomy use of liveview, there is a very nice review of
the EOS40d at http://astrosurf.com/buil/eos40d/test.htm
HTH
fu2 sci.astro.amateur
--
Frédéric

Rita Ä Berkowitz wrote:
> RichA wrote:
>
>>> If I point the camera towards the sun would I be able to view
>>> sunspots without a White-light filter or H-alpha (H-A) filter?
>>
>> Concentrate the light from the unfiltered sun with a lens onto the
>> sensor and KISS it goodby.
>
> I'm just trying to find a valid justification for Live View, that's
> all. So
> far it's not happening. I wonder if I can get Canon to remove it from
> my Mk
> III and get a $25 rebate?
>

Low light shooting, where the sensor is
more sensitive than your eyes (at least after
image processing

BugBear

"Ben Granger" <> wrote in message
news:...
> On Mon, 10 Sep 2007 17:44:55 -0400, Rita Ä Berkowitz <ritaberk2O04
> @aol.com>
> wrote:
>
>>RichA wrote:
>>
>>>> If I point the camera towards the sun would I be able to view
>>>> sunspots without a White-light filter or H-alpha (H-A) filter?
>>>
>>> Concentrate the light from the unfiltered sun with a lens onto the
>>> sensor and KISS it goodby.
>>
>>I'm just trying to find a valid justification for Live View, that's all.
>>
>
> Oh, you're one of those <eye-roll>. Someone who has never obtained any
> experience with all the advanced capabilities of the P&S cameras that far
> surpass anything that any DSLR can do.
>
> How about this then:
>
> When taking images of waterfalls or rapids you can dial-in the slow
> shutter
> speed you need to see how much you are blurring the water, seeing it
> happen in
> real-time in the EVF. Instead of just hoping it'll be right.
Really, EVF previews the long shutter speed? are you sure? So when you have
a 1sec exposure, previewing that would require a framerate of 1 per sec -
that'll be useful I'm sure. Which camera's EVF previews shutter speed? Most
will preview overall exposure, but shutter blur preview, along with live DOF
preview isn't usually a feature. Can you give a specific model that will
preview the amount of shutter blur as you dial it in?

>You can see the
> exact effect you will get on your resulting image, instead of taking a
> photo,
> checking it, resetting to a slower shutter speed, taking another, checking
> it,
> resetting it ... ooops too late, that wading-bird in the scene that made
> it the
> most perfect award-winning photo was scared off by the gawdawful noises
> that
> your DSLR's shutter and slapping mirror were making.
Oops, while you were waiting for your 1 frame/sec EVF to focus, the bird
flew off anyway.. or this 1 frame/sec EVF you are talking about, which is
running 1 second behind live, doesn't show you that the bird flew away
before you press the button.
>Or if you want to dial-in
> the exact amount of motion blur you want in a batter's swing, or a bird's
> wing-beat, or the props of a plane. You will see the effect as you compose
> your
> shot and be able to capture exactly what you want.
Well no, you don't see the effect of the blur, but assuming you did, doing
so would require a delay and so composing on the EVF would be a waste of
time, because the subject would really be gone at the point you press the
button. And just how do you autofocus quickly on a moving subject with an
EVF camera?
If the subject is such that you have enough time to preview the effects on
an EVF, you also have enough time to just take multiple photos.
OR... better yet, use your experience to know good starting exposures, and
take it from there. Heck, that's how we used to take photos back when we
used that four letter F word. The instant feedback of digital is an extra
bonus. Yes previewing the exposure of your photo is handy, but not really
essential.
>
> Unlike every other DSLR on earth with only an OVF where none of this is
> ever
> possible, but it IS possible on nearly every P&S camera in existence with
> an
> LCD/EVF.
>
> Get your head out of your DSLR ass, it's been stuck up there so long with
> your
> ancient technology you can't even see the light.
>

On Sep 10, 10:56 pm, George Anderson <Not_h...@gone.com> wrote:
> Rita Ä Berkowitz wrote:
> > RichA wrote:
>
> >>> If I point the camera towards the sun would I be able to view
> >>> sunspots without a White-light filter or H-alpha (H-A) filter?
>
> >> Concentrate the light from the unfiltered sun with a lens onto the
> >> sensor and KISS it goodby.
>
> > I'm just trying to find a valid justification for Live View, that's
> > all. So
> > far it's not happening. I wonder if I can get Canon to remove it from
> > my Mk
> > III and get a $25 rebate?
>
> > Rita
>
> If the live view on the MkIII is the same thing (or similar) as the 20DA
> came with then slap on a piece of Baader film in front of the 400mm lens
> and you will be able to see a fair bit of detail in the sunspots as well
> as be able to count them.
> The sun is 0.5 of a degree in diameter so from your FOV of the 400 you
> should get an idea of the pixel resolution for the solar image.
>
> George- Hide quoted text -
>
> - Show quoted text -

You need 2000mm of focal length with a 35mm equivalent sensor size to
fill the field of view top of frame to bottom with the Sun. For a 1.5
crop, 1500mm.
Going below this is why camera lens pictures of the Moon, Sun are SO
inferior to longer focal length telescope images. If you can avoid
cropping
a sub-frame sized image, do so.