The fz28 extra zoom debate starts here! (pics)

Here is a crop of a little dragon. It was shot at 5 and 10 MP. This time, I zoomed the 10MP version IN to get the same photo composition edge to edge as I got from the 5MP. This way the same amount of picture area would be in both frames.

Then I took the two versions and cropped the same area out and sized them similarly. This shows what the difference is between 5 and 10 MP.
First the 10MP



Now the 5MP



This is how the two must be compared.

If we don't zoom in the larger MP version to match the smaller, then we are effectively doing the same thing as just cropping the first shot above, looking at the center areas between the crop and the full size and saying "hey, look, they are the same". Well, of course they are, basically!

Djedi

--
Old timer

I want to centralize once more the important points of EZ:

• There normally is no difference between cropping inside the camera by EZ and cropping in a photo editor by post processing.

• If there is a small difference with some cameras it's only because the camera manufacturer used other parameters for the in-camera-processing (noise reduction, JPEG compression) on the smaller cropped images than on the full size images.

Therefore mostly the only adavantage of EZ is:

• to get crops without PP for direct printing and

• to save space on the memory card.

Olaf

JortS29 said:

DjarumBlack said:

I would believe that thermal and atmospheric aberritions would show
up more in longer focal lengths versus cropping. Thats just my
thinking on this. I've made comparisons between cropping on one
camera vs zoom on another, and this is the largest issue I've found.

Dj

Click to expand...

Since they all have the same true focal length, which is what matters
in this (optical) case, all versions (8MP 100% crop, 5MP EZ 100%
crop, 3MP EZ 100% crop) should be equally affected by possible
atmospheric aberrations.

Click to expand...

From experience, I can see distortion caused by eddies more in a zoomed in picture with my FZ3 vs equally cropped picture a my 7.1mp canon. Now, this could be due to better lens in the FZ3, however, the pictures are sharper with more detail with the equally cropped 7.1mp canon. This is just from my experience. When using the same camera to take this test, this might not be the case.

I did a test on an indoor subject, and the images were very similar. But on a hot day taking a picture of a car for example, I could see more detail in the car at an equally cropped 3.2mp image from the canon vs a 3.2 mp image that have the same FOV.

Again, these are two seperate cameras, and maybe there are too many variables to consider.

Dj

djedi said:

Here is a crop of a little dragon. It was shot at 5 and 10 MP. This
time, I zoomed the 10MP version IN to get the same photo composition
edge to edge as I got from the 5MP. This way the same amount of
picture area would be in both frames.
Then I took the two versions and cropped the same area out and sized
them similarly. This shows what the difference is between 5 and 10
MP.
First the 10MP



Now the 5MP



This is how the two must be compared.
If we don't zoom in the larger MP version to match the smaller, then
we are effectively doing the same thing as just cropping the first
shot above, looking at the center areas between the crop and the full
size and saying "hey, look, they are the same". Well, of course they
are, basically!

Djedi

--
Old timer

Click to expand...

The 10mp version looks better IMHO.

Dj

Kurt Horsley said:

--I agree with Steven and Yousaf...the 5mp EZ image is notably
sharper. It's exactly the same with thousands of EZ images with my
FZ50. The 5MP setting seems to be the sweet spot between size and
resolution.

Click to expand...

Kurt Horsley said:

-Kurt Horsley

Click to expand...

--Very interesting observation and I concur for the 1/2.3" size sensor and that mp sweet spot goes up as the sensor size increases or just relates to pizel type and density.

Many miss the lower pixel densities of older digital cameras as better able to handle low light conditions or higher ISO with less noise and have advocated a return to this density sensor. It seems that the FZ28 with 10 mp is just right as with Ezoom you can both extend range by 50% at 5mp setting and maybe even get a sharper pictures in the process or at least just as good? While with the low mp model would be less practical to extend the range as resultion may be too low only 3 mp but still as shown in this test not too shabby.

Another question which needs to be answered is does the lens speed change or get slower as you engage EZoom and how does this effect the ability to auto focus at long tele lengths or you seeing it on EVF or LCD?

What do you think?

safaridon

safaridon said:

Another question which needs to be answered is does the lens speed
change or get slower as you engage EZoom

Click to expand...

--No...it stays faster across the zoom range. Shoot with and without EZ zoom at 300mm (or any other range) and the EZ zoom image is slightly faster/brighter.
-Kurt Horsley

DjarumBlack said:

djedi said:

Here is a crop of a little dragon. It was shot at 5 and 10 MP. This
time, I zoomed the 10MP version IN to get the same photo composition
edge to edge as I got from the 5MP. This way the same amount of
picture area would be in both frames.
Then I took the two versions and cropped the same area out and sized
them similarly. This shows what the difference is between 5 and 10
MP.
First the 10MP



Now the 5MP



This is how the two must be compared.
If we don't zoom in the larger MP version to match the smaller, then
we are effectively doing the same thing as just cropping the first
shot above, looking at the center areas between the crop and the full
size and saying "hey, look, they are the same". Well, of course they
are, basically!

Djedi

--
Old timer

Click to expand...

The 10mp version looks better IMHO.

Dj

Click to expand...

--Dj,
Did you get your images reversed. In your example, the 10mp crop is sharper.
-Kurt Horsley

As far as I understand, djedi is actually trying to show you (and succeeding!) that it is BETTER to use the 10 MP - which I find obvious, but am glad he mentions it.

What the OP shows is that the "cropped zoom" facility is very good, in that it introduces no artifacts or uprezing effects; but it is no different from cropping in PS (except that it is easier and more intuitive for many).
--
Antonio

http://ferrer.smugmug.com/

I looked at the crops and concluded they all came from wideangle shots at different EZ selections. He used the term "full 10MP crop", etc. to describe the 100% shots.
--
Just cruisin' ...



GeeOne, EffZeeEighteen, TeeZeeThree

--At the weekend I was taking some sports shots handheld and the results were superior qn 5ez than 10mp which was down to the faster shutter speed eliminating blur and delighted with the results
Alex

You can use a faster shutter with 5ez than with the full 10 Mp?
Why is that?
Note that I have no personal experience of the EZ mode.
--
Antonio

http://ferrer.smugmug.com/

Kurt Horsley said:

--Geez, you must be kidding...there's no possible way you can qualify
resolution by shooting at a distant tree. You have to use a proper
target. That means one that doesn't move, is flat, has a known value,
and is preferably black and white. Then you need to lock focus and
exposure...that means spot focus and spot meter. Then turn IS off and
use a tripod, and the built in shutter release timer.

And by the way...your 5mp crop IS sharper than the other two. Not by
much, but it's there.

Like I said earlier, if you can't see the difference, you really
don't need to use the EZ mode...but I do salute you for at least
trying. That's far more than most people will do.

Myth busted? Not too sure about that.

-Kurt Horsley

Click to expand...

I agree, second shot is bit sharper.
--
Yousaf Saleem
http://www.yousafsaleem.blogspot.com/
http://www.flickr.com/photos/82672024@N00/

djedi said:

Here is a crop of a little dragon. It was shot at 5 and 10 MP. This
time, I zoomed the 10MP version IN to get the same photo composition
edge to edge as I got from the 5MP. This way the same amount of
picture area would be in both frames.
Then I took the two versions and cropped the same area out and sized
them similarly. This shows what the difference is between 5 and 10
MP.
First the 10MP



Now the 5MP



This is how the two must be compared.
If we don't zoom in the larger MP version to match the smaller, then
we are effectively doing the same thing as just cropping the first
shot above, looking at the center areas between the crop and the full
size and saying "hey, look, they are the same". Well, of course they
are, basically!

Djedi

--
Old timer

Click to expand...

In this shot second one is as if it is texture.
--
Yousaf Saleem
http://www.yousafsaleem.blogspot.com/
http://www.flickr.com/photos/82672024@N00/

--I can see now why these images look reversed. The 10mp image crop was only shot at 290mm. That's 51mm on the actual lens. Not exactly a good choice for a "zoom comparison".

Also, focus was set to pattern instead of spot. There's no telling where the actual focus point was. And there's much more noise in the "5MP" image...which should not be there. Digital noise should be identical if both were shot with the same ISO...but it isn't.
-Kurt Horsley

You must be looking at different things. When I enlarge the files to 300%, there still isn't a noticeable difference here.

Did you check out the second set too?

They were shot at the same focal length, following the theory you posted that the EZ zoom shot wil be brighter/faster.

But ofcourse the EZ zoom shot will have a lower resolution too, so if you take a 100% crop from the 10MP shot, you'll have to enlarge the EZ zoom shot to keep object sizes the same. Which will show the differnce in detail and extra artifacts we are looking at.

When the normal 10 MP setting is changed to the 5 MP or any other EZ Zoom setting, no change occurs in the actual focal length or aperture of the lens. There is therefore no change in the image which is focussed on the sensor.

Choosing an EZ zoom setting simply results in the information from a reduced central area of the sensor being processed while the information from the surrounding pixels is disregarded.

For example, for an FZ50, when a 5 MP EZ zoom shot is taken at the 12x maximum optical zoom setting, only the central 5 MP of the 10 MP sensor is used. The end result is a 5 MP image which corresponds exactly to the central 5 MP of the 10 MP image. There should therefore be no difference in resolution between the 5 MP EZ zoom image and a 5 MP crop from the centre of the 10 MP image.

However as I and several others have stated previously the use of EZ zoom may give a possible improvement in focussing and metering accuracy which can be helpful in some situations such as photographing small birds amongst leaves. It also increases the number of images which can be stored on an SD card and may allow a faster burst rate.

It appears that for some models such as the FZ28, the way in which the maximum aperture of the lens varies with focal length can result in a gain of half a stop or so in speed with the sacrifice of some resolution. This may be achieved by choosing a suitable combination of focal length and acceptable image size.

For the FZ50 the corresponding difference is too small too give any significant benefit and for the FZ20 with its constant F/2.8 lens it makes no difference at all

I trust that clarifies the way in which the EZ zoom operates.

Jimmy
--
J C Brown

As olafk said:

• If there is a small difference with some cameras it's only because the camera manufacturer used other parameters for the in-camera-processing (noise reduction, JPEG compression) on the smaller cropped images than on the full size images.

Click to expand...

That to the best of my knowledge is the only plausible explanation for the differences which some forum members claim to see. IMHO these differences can only be in sharpness not in resolution.

Jimmy
--
J C Brown

I concur.

Hi JortS29,

I will send you my EZ crops by e-mail.

Jimmy
--
J C Brown