What is EZ Zoom?

[1move]

Ok, I'm no Panasonic user, just a possible future FZ28 owner.

I'v seen a few posts of people comparing image quality with and without EZ zoom, but I can't seem to understand what the hell it is. Is it like a digital zoom with less Megapixels?

Sorry for the ignorance. I honestely tried to search it, but did not find a defenition.
Thanks
--
Cheers from Portugal.
Gonçalo.

 

[rdandrea]

It's certainly LIKE that, although as you can tell from reading those other threads, there is no universal agreement.

That's all I'm going to say, I don't want to start ANOTHER of those threads.

 

[radamczak]

Gonçalo, I'm not surprised you haven't been able to find a good definition on the web. As you can see, there are a number of threads running on this forum right now disputing exactly what EZ entails. Unlike digital zoom (often called 'fake' zoom), it is real optical zoom, and is essentially an in-camera crop, which you could achieve equally well (in theory, at least) in PP afterwards. You trade off the lower resolution image for a higher effective focal length and greater range of magnification. However, the reason I and others use it is because it first of all allows you to see exactly what you are photographing, eg small bird or leaf, and should also permit more precise spot focusing and spot metering, resulting in a higher proportion of keepers.
--
Richard

 

[John Carson]

Ok, I'm no Panasonic user, just a possible future FZ28 owner.
I'v seen a few posts of people comparing image quality with and
without EZ zoom, but I can't seem to understand what the hell it is.
Is it like a digital zoom with less Megapixels?

It is in-camera cropping. The image is taken using the centre of the sensor. However, this cropping is not apparent in the viewfinder/LCD, i.e., the image is scaled up so the whole of the viewfinder/LCD is used.

In-camera cropping offers some advantages relative to cropping in post processing:

1. You can meter based on the part of the image you are actually interested in.

2. JPEGs may offer better quality if the image processor only has to deal with a more limited part of the image.

3. Some users claim that they can point the camera more effectively at what they are interested in.

Some people swear by it, but I suspect the benefits are marginal.

--
john carson

 

[Stillhere]

I believe what they're referring to is the extra zoom you can get when you reduce the megapixels that you use.

Panasonic shows it on their website here:

http://panasonic.net/avc/lumix/compact/fz28/lens.html#powerfulzoom

 

[John Carson]

Unlike
digital zoom (often called 'fake' zoom), it is real optical zoom, and
is essentially an in-camera crop, which you could achieve equally
well (in theory, at least) in PP afterwards. You trade off the lower
resolution image for a higher effective focal length and greater
range of magnification. However, the reason I and others use it is
because it first of all allows you to see exactly what you are
photographing, eg small bird or leaf, and should also permit more
precise spot focusing and spot metering, resulting in a higher
proportion of keepers.

I pretty much agree with what you say, except that it is nonsense to call cropping "real optical zoom". Real optical zoom occurs via the lens, not by cropping.

--
john carson

 

[olafk]

Ok, I'm no Panasonic user, just a possible future FZ28 owner.
I'v seen a few posts of people comparing image quality with and
without EZ zoom, but I can't seem to understand what the hell it is.
Is it like a digital zoom with less Megapixels?
Sorry for the ignorance. I honestely tried to search it, but did not
find a defenition.
Thanks
--
Cheers from Portugal.
Gonçalo.

If you really read the last two threads about EZ you must have some kind of humor to start a new one. If not, believe the results of Ianperegian's thread and believe Ian:

http://forums.dpreview.com/forums/read.asp?forum=1033&message=31786579

If you are annoyed about my reaction, please also read the other:

http://forums.dpreview.com/forums/read.asp?forum=1033&message=31750462

Olaf

 

[radamczak]

EZ, or extra zoom, or extended zoom is genuine optical zoom, which DZ is not. The sensor is cropped in EZ, but real optical zoom occurs via the lens.

I pretty much agree with what you say, except that it is nonsense to
call cropping "real optical zoom". Real optical zoom occurs via the
lens, not by cropping.

--
john carson

--
Richard

 

[JortS29]

I pretty much agree with what you say, except that it is nonsense to
call cropping "real optical zoom". Real optical zoom occurs via the
lens, not by cropping.

I think the word zoom is often used in a confusing manner. The zoom ratio between wide angle and tele might increase, the maximum magnification of an object in the output (not the camera screens) does not and the latter is often expected when we talk about more "zoom".

Earlier I mentioned a cake with cream on the center top. Cut away parts of the cake that have no cream. Some would say, there's now more cream. The portion of cream as related to the size of the remaining cake may seem larger, in reality, it's still the same amount.

 

[Andrew Butterfield]

I pretty much agree with what you say, except that it is nonsense to
call cropping "real optical zoom". Real optical zoom occurs via the
lens, not by cropping.

And yet the lens moves...

--
Androo
http://Androo.smugmug.com

 

[JortS29]

And yet the lens moves...

Not when switching to EZ zoom.

 

[J C Brown]

It is in-camera cropping. The image is taken using the centre of the sensor.

However, this cropping is not apparent in the viewfinder/LCD, i.e., the image is scaled up so the whole of the viewfinder/LCD is used.

In-camera cropping offers some advantages relative to cropping in post processing:

1. You can meter based on the part of the image you are actually interested in.

2. JPEGs may offer better quality if the image processor only has to deal with a more limited part of the image.

3. Some users claim that they can point the camera more effectively at what they are interested in.

Some people swear by it, but I suspect the benefits are marginal.

That is an excellent summary John. I agree entirely but would suggest that there may also be some advantage in the ability to focus on a small part of the image.

Jimmy
--
J C Brown

 

[John Carson]

EZ, or extra zoom, or extended zoom is genuine optical zoom, which DZ
is not. The sensor is cropped in EZ, but real optical zoom occurs via
the lens.

So now we have "genuine" optical zoom, which is different from "real" optical zoom.

Marketing department nonsense. Cropping is not optical zoom of any sort. It is not even "zoom". Calling it "optical zoom" is absurd.

--
john carson

 

[radamczak]

John, we all know that real and genuine mean the same thing. What you are suggesting about EZ is incorrect.

EZ, or extra zoom, or extended zoom is genuine optical zoom, which DZ
is not. The sensor is cropped in EZ, but real optical zoom occurs via
the lens.

So now we have "genuine" optical zoom, which is different from "real"
optical zoom.

Marketing department nonsense. Cropping is not optical zoom of any
sort. It is not even "zoom". Calling it "optical zoom" is absurd.

--
john carson

--
Richard

 

[1move]

Ok, thanks everyone for your explanations.
Olaf, I'm not annoyed at all and I do have a really great sense oh humour.
--
Cheers from Portugal.
Gonçalo.

 

[radamczak]

Good for you!

Ok, thanks everyone for your explanations.
Olaf, I'm not annoyed at all and I do have a really great sense oh
humour.
--
Cheers from Portugal.
Gonçalo.

--
Richard

 

[sherman_levine]

Think of it as

"Zoom you can believe in"



Sherm

 

[John_Reed]

--
Just cruisin' ...



GeeOne, EffZeeEighteen, TeeZeeThree

 

[Guy Parsons]

To work out what goes on I charted what the LX3 does, I suspect the other models do much the same. http://homepages.ihug.com.au/~parsog/panasonic/12-ezzoom.html#lens and still working on filling in the gaps in the chart.

What seems to happen is that....

1. 1 you need to choose to use the camera in lower than maximum resolution.

1. 2 the lens stays at the widest setting and downsizes the full resolution image to the selected low resolution and varies that by also cropping and downsizing as you move the zoom lever up until the point where it can't downsize any more, so has to start moving the optical zoom to concentrate on that centre low number of pixels selected as the camera resolution.

1. 3 it's not quite as simple as that but it is a mix of downsizing and optical zoom and the combination and limits vary with the resolution chosen.

It is a marketing device to try and overcome the bad taste in the mouth caused by previously marketing digital zoom as the ninth wonder of the world.

In fact using digital zoom to a sensible limit would be a more honest way to approach this extra zoom problem. That way the camera stays in full resolution all the time and then only interpolates up to full resolution when doing the digital zoom part. But keeping digital zoom to maybe a range of 1.5x to 2x maximum selectable from a menu would be a nice touch and so much easier to manage. The use of the usual full 4x digital zoom means that you are using 1/16 of the number of pixels, turning a 10MP camera into a 0.625MP camera, yuk!

Of course it all depends on your final use of the image, for screen display and small prints you can zoom like crazy and use low resolution, but for large prints then the full resolution of the camera is always needed.

Regards............ Guy

 

[Guy Parsons]

I looked at the FZ28 blurb and it says....

"Plus, the Extra Optical Zoom* uses the center of the CCD to further extend the powerful 18x optical zoom when a resolution of less than 10.1-megapixel is used. This extends the zoom ratio up to 32.1x (35mm equivalent: 866mm) for images with 3-megapixel resolution or less. Adding the Extra Optical Zoom to the 4x digital zoom** extends the total zooming power to a maximum of 128x (35mm equivalent: 3,456mm)."

and below is....

" As digital magnification increases, resolution significantly decreases."

Oh dear, wow (with a very small exclamation mark).

That means they are adding digital zoom to the EZ zoom of 3MP to leave you with a net total of 0.1875MP in-camera. That's 500 x 375 pixels. Maybe good for a small image on screen but never to print.

So ignore the digital zoom on top of EZ zoom, that's just the marketing department w@nkers having fun on a Friday afternoon.

Regards........... Guy

[edit...] EZ zoom seems to be fairly well explained here.....
http://panasonic.net/avc/lumix/popup/ex_zoom/index.html