Sign in with
Sign up | Sign in
Your question

Digital Rebel LCD focus blurry

Last response: in Digital Camera
Share
Anonymous
December 29, 2004 3:36:55 PM

Archived from groups: rec.photo.digital.slr-systems (More info?)

When I try to check for fine focus on the LCD screen, the 4x magnified image
is a little blurry and I can't tell any difference from in and out of focus
areas until I look on my computer monitor. Is there some adjustment to be
made for screen focus? Thanks.
Rich
www.richardclinton.com
Anonymous
December 30, 2004 7:01:10 AM

Archived from groups: rec.photo.digital.slr-systems (More info?)

"RichardClinton" <richardclinton@cox.net> wrote in message
news:KzEAd.24270$Cl3.21378@fed1read03...
> When I try to check for fine focus on the LCD screen, the 4x magnified
> image is a little blurry and I can't tell any difference from in and out
> of focus areas until I look on my computer monitor. Is there some
> adjustment to be made for screen focus? Thanks.


I've never been able to check focus with the LCD, even with zooming. It just
doesn't work.
Anonymous
January 2, 2005 2:53:38 AM

Archived from groups: rec.photo.digital.slr-systems (More info?)

"Dave R knows who" <nguser2u@spamnotAOL.com> wrote in message
news:a4LAd.15346$_3.177744@typhoon.sonic.net...
>
> "RichardClinton" <richardclinton@cox.net> wrote in message
> news:KzEAd.24270$Cl3.21378@fed1read03...
>> When I try to check for fine focus on the LCD screen, the 4x magnified
>> image is a little blurry and I can't tell any difference from in and out
>> of focus areas until I look on my computer monitor. Is there some
>> adjustment to be made for screen focus? Thanks.
>
>
> I've never been able to check focus with the LCD, even with zooming. It
> just doesn't work.

Hang on! Are you guys talking about the EVF focus, cause I have no way of
focusing through the LCD when taking a shot. Or am I confused as usual?
Related resources
Anonymous
January 2, 2005 4:33:08 AM

Archived from groups: rec.photo.digital.slr-systems (More info?)

> > When I try to check for fine focus on the LCD screen, the 4x magnified
> > image is a little blurry and I can't tell any difference from in and out
> > of focus areas until I look on my computer monitor. Is there some
> > adjustment to be made for screen focus? Thanks.

While I can't say for sure, this is what I *think* is causing it:

Doing full-quality decompression of a full-size JPEG from the Digital
Rebel not only takes a fair amount of processing cycles, it also takes a
pretty good amount of memory in which to store the image. Because of those
constraints, when displaying the image on the LCD screen, a full-quality
decompression isn't done - the camera does a "quick & dirty" decompression
to obtain an image of a resolution suitable to the LCD panel, or maybe a
small bit above. When you zoom in on the image, it's just magnifying that
low-res version, *not* going back and performing another decompression of
the original.

Zooming in on a photo shot in "raw" mode seems to be a bit sharper on the
LCD than one shot in JPEG, but still nowhere near what the LCD *could* be
displaying if fed the proper information. Because of that, I imagine that
the camera simply takes a down-sized version of the RAW data to display, and
simply magnifies that to let you "zoom".

As always, I could be wrong.

steve
Anonymous
January 2, 2005 7:40:39 PM

Archived from groups: rec.photo.digital.slr-systems (More info?)

RichardClinton wrote:
>
> When I try to check for fine focus on the LCD screen, the 4x magnified image
> is a little blurry and I can't tell any difference from in and out of focus
> areas until I look on my computer monitor. Is there some adjustment to be
> made for screen focus? Thanks.
> Rich
> www.richardclinton.com

Mine is too, though when I got the 17-85mm IS lens, the magnified view
on the LCD wasn't nearly as burry as with the kit lens, though it still
is a little.

Colin
Anonymous
January 3, 2005 12:31:02 AM

Archived from groups: rec.photo.digital.slr-systems (More info?)

Toomanyputters wrote:
>
> "Dave R knows who" <nguser2u@spamnotAOL.com> wrote in message
> news:a4LAd.15346$_3.177744@typhoon.sonic.net...
> >
> > "RichardClinton" <richardclinton@cox.net> wrote in message
> > news:KzEAd.24270$Cl3.21378@fed1read03...
> >> When I try to check for fine focus on the LCD screen, the 4x magnified
> >> image is a little blurry and I can't tell any difference from in and out
> >> of focus areas until I look on my computer monitor. Is there some
> >> adjustment to be made for screen focus? Thanks.
> >
> >
> > I've never been able to check focus with the LCD, even with zooming. It
> > just doesn't work.
>
> Hang on! Are you guys talking about the EVF focus, cause I have no way of
> focusing through the LCD when taking a shot. Or am I confused as usual?

No, we are talking about post-shot viewing on the LCD. You can zoom the
image with the button at top right of the camera up to 10x the original
image size, and navigate round the image with the < and > buttons.

Colin
Anonymous
January 3, 2005 3:41:56 AM

Archived from groups: rec.photo.digital.slr-systems (More info?)

On 2005-01-02, Colin D <ColinD@killspam.127.0.0.1> wrote:
>
>
> Toomanyputters wrote:
>>
>> "Dave R knows who" <nguser2u@spamnotAOL.com> wrote in message
>> news:a4LAd.15346$_3.177744@typhoon.sonic.net...
>> >
>> > "RichardClinton" <richardclinton@cox.net> wrote in message
>> > news:KzEAd.24270$Cl3.21378@fed1read03...
>> >> When I try to check for fine focus on the LCD screen, the 4x magnified
>> >> image is a little blurry and I can't tell any difference from in and out
>> >> of focus areas until I look on my computer monitor. Is there some
>> >> adjustment to be made for screen focus? Thanks.
>> >
>> >
>> > I've never been able to check focus with the LCD, even with zooming. It
>> > just doesn't work.
>>
>> Hang on! Are you guys talking about the EVF focus, cause I have no way of
>> focusing through the LCD when taking a shot. Or am I confused as usual?
>
> No, we are talking about post-shot viewing on the LCD. You can zoom the
> image with the button at top right of the camera up to 10x the original
> image size, and navigate round the image with the < and > buttons.
>
> Colin

Ha! I was reading this thread and trying to imagine how these
newfangled DSLRs got an image to the LCD on a continuing basis. Pellix
mirrors? Mirrors that cycle > 30 Hz continuously? Noiselessly!? Walk
around looking at the LCD instead of the viewfinder, like the non SLR
digitals? I was starting to get excited!

What the hell have I missed!

:o 

Will D.
Anonymous
January 4, 2005 12:34:11 AM

Archived from groups: rec.photo.digital.slr-systems (More info?)

"Will D." wrote:
>
> >
> > No, we are talking about post-shot viewing on the LCD. You can zoom the
> > image with the button at top right of the camera up to 10x the original
> > image size, and navigate round the image with the < and > buttons.
> >
> > Colin
>
> Ha! I was reading this thread and trying to imagine how these
> newfangled DSLRs got an image to the LCD on a continuing basis. Pellix
> mirrors? Mirrors that cycle > 30 Hz continuously? Noiselessly!? Walk
> around looking at the LCD instead of the viewfinder, like the non SLR
> digitals? I was starting to get excited!
>
> What the hell have I missed!
>
Well, youve missed some, but you're in good company, as many others have
asked the same question. DSLR's do not have preview on the LCD. They
have optical reflex finders as in film SLR's, and the LCD will show you
the shot after you have taken it, together with histogram info etc.

DSLR's have mechanical shutters, and the sensor is not exposed until the
shot is taken. Additionally, the mirror would be in the way if the
shutter wasn't there, or was open.

Colin
Anonymous
January 4, 2005 12:34:12 AM

Archived from groups: rec.photo.digital.slr-systems (More info?)

On 2005-01-03, Colin D <ColinD@killspam.127.0.0.1> wrote:
>
>
> "Will D." wrote:
>>
>> >
>> > No, we are talking about post-shot viewing on the LCD. You can zoom the
>> > image with the button at top right of the camera up to 10x the original
>> > image size, and navigate round the image with the < and > buttons.
>> >
>> > Colin
>>
>> Ha! I was reading this thread and trying to imagine how these
>> newfangled DSLRs got an image to the LCD on a continuing basis. Pellix
>> mirrors? Mirrors that cycle > 30 Hz continuously? Noiselessly!? Walk
>> around looking at the LCD instead of the viewfinder, like the non SLR
>> digitals? I was starting to get excited!
>>
>> What the hell have I missed!
>>
> Well, youve missed some, but you're in good company, as many others have
> asked the same question. DSLR's do not have preview on the LCD. They
> have optical reflex finders as in film SLR's, and the LCD will show you
> the shot after you have taken it, together with histogram info etc.
>
> DSLR's have mechanical shutters, and the sensor is not exposed until the
> shot is taken. Additionally, the mirror would be in the way if the
> shutter wasn't there, or was open.
>
> Colin

Aw shoot! You mean that DSLRs are nothing more than SLRs with a digital
sensor instead of emulsion film? Here I was all set to get excited
about some automagical whizbang I'd never heard of before! Dang!
Finding out that you knew what was going on all along sure is boring...

At least with DSLRs you get an instant return mirror. The non SLR
digitals blank out the LCD during image storage, which means that if you
are following the action, you'd better be using the optical viewfinder,
for whatever good that would do. With shutter lag, you won't get what
you want anyway.

Wonder how many people that are used to the viewfinder digitals actually
expect DSLRs to have a continuous LCD readout? Wonder how many of those
know what an SLR camera is? RFL!!

Will D.
Anonymous
January 4, 2005 12:34:13 AM

Archived from groups: rec.photo.digital.slr-systems (More info?)

"Will D." <willd@no.spam> wrote in message
news:10tj94cs6m2dcf7@corp.supernews.com...
> On 2005-01-03, Colin D <ColinD@killspam.127.0.0.1> wrote:
>>
>>
>
> Wonder how many people that are used to the viewfinder digitals actually
> expect DSLRs to have a continuous LCD readout? Wonder how many of those
> know what an SLR camera is? RFL!!
>
> Will D.
>

Ok, what's an SLR camera....;>
Anonymous
January 5, 2005 4:20:20 AM

Archived from groups: rec.photo.digital.slr-systems (More info?)

On 2005-01-03, Rudy Benner <bennerREMOVE@personainternet.com> wrote:
>
> "Will D." <willd@no.spam> wrote in message
> news:10tj94cs6m2dcf7@corp.supernews.com...
>> On 2005-01-03, Colin D <ColinD@killspam.127.0.0.1> wrote:
>>>
>>>
>>
>> Wonder how many people that are used to the viewfinder digitals actually
>> expect DSLRs to have a continuous LCD readout? Wonder how many of those
>> know what an SLR camera is? RFL!!
>>
>> Will D.
>>
>
> Ok, what's an SLR camera....;>

Simple Light Rugged camera? Well, they used to be, at least compared to
a Speed Graphic. Now, how about Super Luxurious Robot? And then if you
ask the elite snobs that only tote a Leica M, it's probably Stoopid Loser
Rangefinder-wannabe.

What's that you say? Three strikes and out? Oh okay...

You're up to bat, Rudy.

;) 

Will D.
Anonymous
January 10, 2005 11:30:29 PM

Archived from groups: rec.photo.digital.slr-systems (More info?)

It just doesn't seem logical ( what else is new?) to have zoom in capacity
that yields a blurry image. Would that it could show the area of focus
point in greater detail. Has anyone with the hacked firmware version
http://www.bahneman.com/liem/photos/tricks/digital-rebe...
had a different experence? Why would the 17-85 IS lens give sharper zoom in
than the 18-55? Any thoughts?
Rich
www.richardclinton.com


"Steve Wolfe" <unt@codon.com> wrote in message
news:33ppvfF41lvmvU1@individual.net...
>> > When I try to check for fine focus on the LCD screen, the 4x magnified
>> > image is a little blurry and I can't tell any difference from in and
>> > out
>> > of focus areas until I look on my computer monitor. Is there some
>> > adjustment to be made for screen focus? Thanks.
>
> While I can't say for sure, this is what I *think* is causing it:
>
> Doing full-quality decompression of a full-size JPEG from the Digital
> Rebel not only takes a fair amount of processing cycles, it also takes a
> pretty good amount of memory in which to store the image. Because of
> those
> constraints, when displaying the image on the LCD screen, a full-quality
> decompression isn't done - the camera does a "quick & dirty" decompression
> to obtain an image of a resolution suitable to the LCD panel, or maybe a
> small bit above. When you zoom in on the image, it's just magnifying that
> low-res version, *not* going back and performing another decompression of
> the original.
>
> Zooming in on a photo shot in "raw" mode seems to be a bit sharper on the
> LCD than one shot in JPEG, but still nowhere near what the LCD *could* be
> displaying if fed the proper information. Because of that, I imagine that
> the camera simply takes a down-sized version of the RAW data to display,
> and
> simply magnifies that to let you "zoom".
>
> As always, I could be wrong.
>
> steve
>
>
"Mine is too, though when I got the 17-85mm IS lens, the magnified view
on the LCD wasn't nearly as burry as with the kit lens, though it still
is a little.

Colin"
Anonymous
January 12, 2005 2:06:59 PM

Archived from groups: rec.photo.digital.slr-systems (More info?)

RichardClinton wrote:
>
> It just doesn't seem logical ( what else is new?) to have zoom in capacity
> that yields a blurry image. Would that it could show the area of focus
> point in greater detail. Has anyone with the hacked firmware version
> http://www.bahneman.com/liem/photos/tricks/digital-rebe...
> had a different experence? Why would the 17-85 IS lens give sharper zoom in
> than the 18-55? Any thoughts?
> Rich
Well, the 17-85mm lens is a better lens than the kit lens - which is not
to say the kit lens is not good, it just isn't as good. Also,
autofocus, by its nature, has a tolerance built in to prevent constant
hunting while focusing. A misfocus within the tolerance amount will not
initiate a re-focus, so the shot can be slightly out of focus, and at
10x up on the LCD you can see this.

BTW, this tolerance, or hysteresis, is common to all autofocus systems,
and not limited to any particular make.

Colin.
Anonymous
January 20, 2005 3:35:34 AM

Archived from groups: rec.photo.digital.slr-systems (More info?)

> While I can't say for sure, this is what I *think* is causing it:
>
> Zooming in on a photo shot in "raw" mode seems to be a bit sharper on
the
> LCD than one shot in JPEG, but still nowhere near what the LCD *could* be
> displaying if fed the proper information. Because of that, I imagine that
> the camera simply takes a down-sized version of the RAW data to display,
and
> simply magnifies that to let you "zoom".
>
> As always, I could be wrong.

I got digging through the exif data tonight with a Perl module
(Image::ExifTool), and found that the camera does, indeed, use a low-res
image for display on the LCD panel. The Exif data has both a thumbnail
image (160x120, 8k), and a preview image (1536x1024, 221k).

For fun, I extracted the preview image, and blew it up a little bit, and
it is of noticeably lesser quality than the original JPG - given the file
size of only 221k, you'd expect that. The LCD has 118,000 pixels, which
makes it (I believe) 420x280. That means that you can only zoom in to about
a 1:4 ratio before you run out of resolution in that preview image, and the
camera will have to start upsampling to give you something to look at. At
higher zooms on the viewfinder, because it has to upsample, it could either
show you something blocky and pixellated, or anti-aliased and "blurry" - it
looks like Canon chose the blurry. : )

Interestingly enough, there is also exif data embedded in both the preview
and thumbnail images - exif data embedded in images which are embedded in
the exif data embedded in an image!

steve
January 20, 2005 6:00:32 AM

Archived from groups: rec.photo.digital.slr-systems (More info?)

RichardClinton wrote:

> It just doesn't seem logical ( what else is new?) to have zoom in capacity
> that yields a blurry image.

I've been using this function on my OM E300 and it gets sharper and more
detailed up to the 10X max, easy to see if it's a keeper or not so this
-is- possible to do well. Just something canon decided to do this other
way?

--

Stacey
Anonymous
January 20, 2005 10:39:34 AM

Archived from groups: rec.photo.digital.slr-systems (More info?)

Steve Wolfe wrote:
> The LCD has 118,000 pixels, which makes it (I believe) 420x280.

It might be worse than that - it may 118,000 of red + green + blue pixels,
i.e. only about 39,000 full-colour pixels.....

David
!