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Question

What digital camera to buy when changing from a SLR

Aug 17, 2011 5:02PM PDT

I have a Nikon D60 with a 55-200mm lens as my longer zooming lens.
I am travelling in a few weeks and don't want to carry all the weight of the SLR.
I am thinking of buying a digital camera which will give me almost as good pics as the SLR.
I am confused between the different types of zooms on the SLR (eg measured in mm) and on digital (measured in x). Can somebody please explain.
A friend had the Panasonic Lumix DMC-TZ10 and it was a great camera so I was thinking of the updated model the TZ20, but too expensive. Has anybody got a Sony H70?
Thanks for your help

Discussion is locked

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Answer
DSLR to point-n-shoot
Aug 18, 2011 12:23AM PDT

Determining the zoom is quite easy.
Your 55-200mm lens is 3.6X zoom.
Divide 200 by 55.

The thing you will notice most about any point-n-shoot camera is noise.
With the very small sensor assembly they use, crowding many megapixels onto such a small surface means they have less output, requiring the camera maker to crank up the amplification.
(much like turning up the volume on a small inexpensive radio)
(with a radio you get distortion, with a sensor you get noise)
That means low light performance is poor.

Rule of thumb is - never go higher than ISO 400 with a small camera.
A DSLR can go to ISO 3200 and still produce less noise than a small camera at ISO 400.

The Sony H70 uses one of those 16 megapixel sensor assemblies.
It produces even more noise than a 12 or 14 megapixel camera.
Because they have crowded even more pixels onto a too small sensor.
10, 12, 14 & 16 megapixel cameras all use the same size sensor assembly.
The 10 produces the least noise.
With the 16 megapixel sensor, the camera makers have to use noise reduction firmware in the camera.
They usually have to be very aggressive with that noise reduction and that also removes the very small details, which will leave you with soft images.

..

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Answer
Comparing (zoom) lenses on different size snesors
Aug 18, 2011 11:52AM PDT

In addition to what snapshot2 wrote, you may also want to consider "crop factor" which is usually measured relative to a 35mm "full frame" image area.

e.g. I believe your D60 has a crop factor of 1.5 so pictures taken with the 55-200mm lens have a similar field of view as pictures taken with 82-300mm (55x1.5 to 200x1.5) lens on a full frame camera.

Now that you know the 35mm equivalent of your D60+lens combo, you can check the specs of the H70:

http://reviews.cnet.com/digital-cameras/sony-cyber-shot-dsc/4507-6501_7-34469438.html?tag=mncolBtm;rnav

and scroll down to where it says:

"Focal Length Equivalent to 35mm Camera 25-250mm"

In short, the field of view of H70 is wider when zoomed out and shorter when zoomed in.

The tricky part is to separate magnification and crop factor. So the 42.5mm lens on the H70 will give you less magnification than the 55-200mm. But the smaller sensor will only capture the center of the image, cropping away the top/bottom and sides. There are a bunch of web tutorials/calculators on/for this if you do a search for "crop factor" and/or "field of view"

Mark