Can Live View Be Used To Count Sunspots?

On 9/12/07 1:34 PM, in article 1189622089.822773@athprx03, "gpaleo"
<gpaleo RemoveThis @ath.forthnet.gr> wrote:

> ? "Battleax" <unavailable RemoveThis @thistime.net> ?????? ??? ??????
> news:af600$46e8273e$d1d94f68$32499@PRIMUS.CA...
>>
>> If you aren't running a scan-back then you're all loosers
>
>
>
> OK, I'll bite, what's a scan-back????
>
Better yet, what's a "looser"? Is it opposite a "tighter"?
 >> Stay informed about: Can Live View Be Used To Count Sunspots? 

In article <ebydnXUGrKF5BHjbnZ2dnUVZ_ternZ2d.DeleteThis@comcast.com>, William
Graham <weg9.DeleteThis@comcast.net> wrote:

> "StarStruck" <astroman.DeleteThis@noaddress.net> wrote in message
> news:tbbae3hc124120l3tvklip8r8l4jfajn9d@4ax.com...
> > On Mon, 10 Sep 2007 07:15:32 -0400, Rita Ä Berkowitz <ritaberk2O04
> > @aol.com>
> > 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?

> 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.....

I doubt if the pinhole will show sunspots.

I tried a pinhole to view the transit of Mercury across the face of the
Sun a few years ago. Couldn't see the planet at all.

What worked better was using the optics in a pair of binoculars to
create an image on paper. Much better resolution and contrast than the
pinhole. With this, we were able to watch the transit of Mercury very
well.

I don't know for sure, but I suspect that sunspots will be harder to
see than Mercury in front of the Sun.

Hope this helps.

-- Sally

--
Sally Shears (a.k.a. "Molly")
SallyShears.DeleteThis@gmail.com -or- Sally.DeleteThis@Shears.org
SallyShears (at) gmail (dot) com
 >> Stay informed about: Can Live View Be Used To Count Sunspots? 

"Sally Shears" <SallyShears.DeleteThis@gmail.com> wrote in message
news:120920072340124440%SallyShears@gmail.com...
> In article <ebydnXUGrKF5BHjbnZ2dnUVZ_ternZ2d.DeleteThis@comcast.com>, William
> Graham <weg9.DeleteThis@comcast.net> wrote:
>
>> "StarStruck" <astroman.DeleteThis@noaddress.net> wrote in message
>> news:tbbae3hc124120l3tvklip8r8l4jfajn9d@4ax.com...
>> > On Mon, 10 Sep 2007 07:15:32 -0400, Rita Ä Berkowitz <ritaberk2O04
>> > @aol.com>
>> > 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?
>
>> 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.....
>
> I doubt if the pinhole will show sunspots.
>
> I tried a pinhole to view the transit of Mercury across the face of the
> Sun a few years ago. Couldn't see the planet at all.
>
> What worked better was using the optics in a pair of binoculars to
> create an image on paper. Much better resolution and contrast than the
> pinhole. With this, we were able to watch the transit of Mercury very
> well.
>
> I don't know for sure, but I suspect that sunspots will be harder to
> see than Mercury in front of the Sun.
>
> Hope this helps.
>
> -- Sally
>
Yes, a lens will work much better than a pinhole, if it's the right kind of
lens....
 >> Stay informed about: Can Live View Be Used To Count Sunspots? 

On Wed, 12 Sep 2007 23:40:12 -0400, Sally Shears
<SallyShears.TakeThisOut@gmail.com> wrote:

>In article <ebydnXUGrKF5BHjbnZ2dnUVZ_ternZ2d.TakeThisOut@comcast.com>, William
>Graham <weg9.TakeThisOut@comcast.net> wrote:
>
>> "StarStruck" <astroman.TakeThisOut@noaddress.net> wrote in message
>> news:tbbae3hc124120l3tvklip8r8l4jfajn9d@4ax.com...
>> > On Mon, 10 Sep 2007 07:15:32 -0400, Rita Ä Berkowitz <ritaberk2O04
>> > @aol.com>
>> > 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?

Good way to destroy the sensor and you still have to focus the thing.
Looking through the camera to focus on the sun would be dangerous.


Just put multiple layers of aluminized Mylar over the lens. Use at
least 5 or 6 layers. If it's too dark, remove one layer at a time.
Normally even two layers will let through too much light.


>
>> 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.....
>
>I doubt if the pinhole will show sunspots.
>
>I tried a pinhole to view the transit of Mercury across the face of the
>Sun a few years ago. Couldn't see the planet at all.

That is because Mercury is so tiny. Many sunspots are larger than the
earth and are easily visible using a pinhole for projection. OTOH it
takes a bit of experimentation for the size of the pinhole. All
pinholes are not created equal.

>
>What worked better was using the optics in a pair of binoculars to
>create an image on paper. Much better resolution and contrast than the
>pinhole. With this, we were able to watch the transit of Mercury very
>well.

Good way to melt the glue in the optics. I've done this and had the
eyepieces get almost too hot to touch.

>
>I don't know for sure, but I suspect that sunspots will be harder to
>see than Mercury in front of the Sun.

They are much easier as many are much larger than Mercury..

Roger (K8RI)

>
>Hope this helps.
>
> -- Sally
 >> Stay informed about: Can Live View Be Used To Count Sunspots? 

In article <1189622089.822773@athprx03>, gpaleo.TakeThisOut@ath.forthnet.gr says...
> Ï "Battleax" <unavailable.TakeThisOut@thistime.net> Ýãñáøå óôï ìÞíõìá
> news:af600$46e8273e$d1d94f68$32499@PRIMUS.CA...
> >
> > If you aren't running a scan-back then you're all loosers
>
>
>
> OK, I'll bite, what's a scan-back????
>
>
and what are we all looser than?
 >> Stay informed about: Can Live View Be Used To Count Sunspots? 

On Thu, 13 Sep 2007 06:55:47 GMT, Irwin Peckinloomer wrote:

>>> If you aren't running a scan-back then you're all loosers
>>
>> OK, I'll bite, what's a scan-back????
>>
> and what are we all looser than?

A stool, and not the three or four-legged kind.
 >> Stay informed about: Can Live View Be Used To Count Sunspots? 

In rec.photo.digital.slr-systems William Graham <weg9.TakeThisOut@comcast.net> wrote:

> "Sally Shears" <SallyShears.TakeThisOut@gmail.com> wrote in message
> news:120920072340124440%SallyShears@gmail.com...
>> In article <ebydnXUGrKF5BHjbnZ2dnUVZ_ternZ2d.TakeThisOut@comcast.com>, William
>> Graham <weg9.TakeThisOut@comcast.net> wrote:
>>
>>> "StarStruck" <astroman.TakeThisOut@noaddress.net> wrote in message
>>> news:tbbae3hc124120l3tvklip8r8l4jfajn9d@4ax.com...
>>> > On Mon, 10 Sep 2007 07:15:32 -0400, Rita ? Berkowitz <ritaberk2O04
>>> > @aol.com>
>>> > 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?
>>
>>> 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.....
>>
>> I doubt if the pinhole will show sunspots.
>>
>> I tried a pinhole to view the transit of Mercury across the face of the
>> Sun a few years ago. Couldn't see the planet at all.
>>
>> What worked better was using the optics in a pair of binoculars to
>> create an image on paper. Much better resolution and contrast than the
>> pinhole. With this, we were able to watch the transit of Mercury very
>> well.
>>
>> I don't know for sure, but I suspect that sunspots will be harder to
>> see than Mercury in front of the Sun.
>>
>> Hope this helps.
>>
>> -- Sally
>>
> Yes, a lens will work much better than a pinhole, if it's the right kind of
> lens....

A big long focus lens is all you need, e.g. the usual telescope objective.

--
Chris Malcolm cam.TakeThisOut@infirmatics.ed.ac.uk DoD #205
IPAB, Informatics, JCMB, King's Buildings, Edinburgh, EH9 3JZ, UK
[http://www.dai.ed.ac.uk/homes/cam/]
 >> Stay informed about: Can Live View Be Used To Count Sunspots? 

Alan Browne <alan.browne DeleteThis @FreelunchVideotron.ca> wrote in news:mA_Fi.14670
$rl5.255278@weber.videotron.net:

> Battleax wrote:
>> If you aren't running a scan-back then you're all loosers
>
> Yes, many loose Canon's around here scanning the backs of their cameras
> going ooh!
>

ooh ooh!! Hence the term "Chimping"
 >> Stay informed about: Can Live View Be Used To Count Sunspots? 

Irwin Peckinloomer wrote:
> In article <1189622089.822773@athprx03>, gpaleo.RemoveThis@ath.forthnet.gr
> says...
>> Ï "Battleax" <unavailable.RemoveThis@thistime.net> Ýãñáøå óôï ìÞíõìá
>> news:af600$46e8273e$d1d94f68$32499@PRIMUS.CA...
>>>
>>> If you aren't running a scan-back then you're all loosers
>>
>>
>>
>> OK, I'll bite, what's a scan-back????
>>
>>
> and what are we all looser than?
 >> Stay informed about: Can Live View Be Used To Count Sunspots? 

Irwin Peckinloomer wrote:
> In article <1189622089.822773@athprx03>, gpaleo.RemoveThis@ath.forthnet.gr
> says...
>> Ï "Battleax" <unavailable.RemoveThis@thistime.net> Ýãñáøå óôï ìÞíõìá
>> news:af600$46e8273e$d1d94f68$32499@PRIMUS.CA...
>>>
>>> If you aren't running a scan-back then you're all loosers
>>
>>
>>
>> OK, I'll bite, what's a scan-back????
>>
>>
> and what are we all looser than?

Loosers loose things, as in loosing a few well-directed rounds in the
direction of ijit troles.

Die, Ijit troles!

--
Frank ess
 >> Stay informed about: Can Live View Be Used To Count Sunspots? 

Alfred Molon wrote:

>>1. Noise levels are much lower in DSLRs due to the much larger pixels
>>of a DSLR sensor.
>
> Only if you use high ISO settings. At low ISO settings noise is not an
> issue with decent compacts.
>
>>This means that in low light situations, the DSLR will
>>produce FAR superior results.
>
> You can use a large aperture and still have sufficient DOF or a longer
> exposure time. It's only when you can't use a long exposure time that
> you have to push up the ISO.

P&S don't offer anything faster than f/2.8 at wide angle, less for
telephoto. The smaller sensor also limits dynamic range.


>>Also...Flash pictures will suffer much less from red-eye,
>>because the distance between the front lens element and the flash is
>>much greater on a DSLR. This is especially advantageous if you add a
>>shoe mounted flash...which will virtually eliminate red-eye.
>
> There are lots of compacts with a flash hotshoe.
>
>>2. Shutter-lag (or the delay between the time you press the button,
>>and picture actually takes) is much reduced with DSLRs, meaning you
>>won't miss those split-second shots.
>
> Even here there are compact cameras with low shutter lags.
>
>>4. Options! DSLR users have the option of other lenses, many of
>>which have special purposes...like macro for close-ups...tele for
>>sports or wildlife...or super wide angle.
>
> Yes, that's an advantage which comes at a price however: the time you
> need to change the lens, dust coming in, extra bulk and weight.
>
>>Remote shutter releases are also available, along
>>with countless other things...
>>like off-camera flash systems, and on and on.
>
> Also available for compacts.
>
>>5. Wide angle deserves its own "point" since most point-and-shoots
>>don't offer much in terms of wide angle. This means that for landscapes,
>>or for interior shots where you can only back up so far...the
>>point-and-shooter is often wishing
>>for a wider-angle lens. DSLRs accept these, where it's quite an
>>optical compromise to force a P&S to do this.
>
> The Sony R1 starts at 24mm, with a wide angle converter at 19mm. If that
> is not enough you can do panorama stitching to get any focal length you
> want.

That's neither compact nor inexpensive, it has an APS sensor and lens
equivalent to an APS DSLR with a 36-180mm f/2.8-4.8 And as mentioned,
the wide angle converter is a compromised version.
 >> Stay informed about: Can Live View Be Used To Count Sunspots? 

x man or what ever you want to be called these days you are so boring
you would never make a good troll at least try something different
that is worthly of a reply YYYYYYYyyaawwwwwwwnnn!!!
 >> Stay informed about: Can Live View Be Used To Count Sunspots? 

"Chris Malcolm" <cam.TakeThisOut@holyrood.ed.ac.uk> wrote in message
news:5ksjmsF5b8vrU7@mid.individual.net...
> In rec.photo.digital.slr-systems William Graham <weg9.TakeThisOut@comcast.net> wrote:
>
>> "Sally Shears" <SallyShears.TakeThisOut@gmail.com> wrote in message
>> news:120920072340124440%SallyShears@gmail.com...
>>> In article <ebydnXUGrKF5BHjbnZ2dnUVZ_ternZ2d.TakeThisOut@comcast.com>, William
>>> Graham <weg9.TakeThisOut@comcast.net> wrote:
>>>
>>>> "StarStruck" <astroman.TakeThisOut@noaddress.net> wrote in message
>>>> news:tbbae3hc124120l3tvklip8r8l4jfajn9d@4ax.com...
>>>> > On Mon, 10 Sep 2007 07:15:32 -0400, Rita ? Berkowitz <ritaberk2O04
>>>> > @aol.com>
>>>> > 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?
>>>
>>>> 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.....
>>>
>>> I doubt if the pinhole will show sunspots.
>>>
>>> I tried a pinhole to view the transit of Mercury across the face of the
>>> Sun a few years ago. Couldn't see the planet at all.
>>>
>>> What worked better was using the optics in a pair of binoculars to
>>> create an image on paper. Much better resolution and contrast than the
>>> pinhole. With this, we were able to watch the transit of Mercury very
>>> well.
>>>
>>> I don't know for sure, but I suspect that sunspots will be harder to
>>> see than Mercury in front of the Sun.
>>>
>>> Hope this helps.
>>>
>>> -- Sally
>>>
>> Yes, a lens will work much better than a pinhole, if it's the right kind
>> of
>> lens....
>
> A big long focus lens is all you need, e.g. the usual telescope objective.
>
Well, my original point was to project the image onto a screen, rather than
to look at it directly....This can be done with either a lens or a pinhole,
and naturally, a lens would be better....
 >> Stay informed about: Can Live View Be Used To Count Sunspots?