pixel density

How does pixel density influence the resolution at super telephoto?
For example: Is it better to buy a:

1. Nikon 8800 with a teleconverter
2.Olympus e300 2x crop factor
3.Canon 350d 1.5 or 1.6 crop factor
4.Panasonic FZ20 with a 2.8/420mm x teleconverter?
5.7mpix consumer camera disassembled and lens replaced with a 35mm slr lens

Lens options:
1.Opteka/Exakta/Samiyang/Vivitar/whatever 650-1300mm f/8-f16 lens (1300mm
f/8 EFL Olympus) (teleconverter???) 250 Eur
2.100-400 f/5.6 with 1.4x teleconverter 500 Eur
3.80-200 f/2.8 Tamron or Tokina with a 3x Kenko teleconverter 600 Eur + 250
Eur
4.600 mm f/8 mirror
5.50-500mm f/6.3 Sigma with 2x and 1.4x teleconverters
6. A diy project of makeing the lens myself from components (found a front
lens 17cm diameter)
7. A telescope with an adapter 6 inch 1200 f/8 refractor 500 Eur + adapter

My goal is to get an image similar to the one from 20x50 binoculars or
better.
50mm lens is normal 1x, then 1000mm is 20x normal???

Thanks in advance.

".::SuperBLUE::." wrote in message

| How does pixel density influence the resolution at super telephoto?
| For example: Is it better to buy a:
|
| 1. Nikon 8800 with a teleconverter
| 2.Olympus e300 2x crop factor
| 3.Canon 350d 1.5 or 1.6 crop factor
| 4.Panasonic FZ20 with a 2.8/420mm x teleconverter?
| 5.7mpix consumer camera disassembled and lens replaced with a 35mm slr lens
|
| Lens options:
| 1.Opteka/Exakta/Samiyang/Vivitar/whatever 650-1300mm f/8-f16 lens (1300mm
| f/8 EFL Olympus) (teleconverter???) 250 Eur
| 2.100-400 f/5.6 with 1.4x teleconverter 500 Eur
| 3.80-200 f/2.8 Tamron or Tokina with a 3x Kenko teleconverter 600 Eur + 250
| Eur
| 4.600 mm f/8 mirror
| 5.50-500mm f/6.3 Sigma with 2x and 1.4x teleconverters
| 6. A diy project of makeing the lens myself from components (found a front
| lens 17cm diameter)
| 7. A telescope with an adapter 6 inch 1200 f/8 refractor 500 Eur + adapter
|
| My goal is to get an image similar to the one from 20x50 binoculars or
| better.
| 50mm lens is normal 1x, then 1000mm is 20x normal???
|
| Thanks in advance.

It seems to me that "pixel density" is a digital construct so the lenses don't play in this,
the MP resolution of the dSLR will and how the digital representation is rendered on the
computer.

--
Dave

It seems to me that "pixel density" is a digital construct so the lenses
don't play in this,
the MP resolution of the dSLR will and how the digital representation is
rendered on the
computer.

Ok, how can you compare a prosumer Nikon 8800 with a dslr if no lenses are
mentioned?
Price range is also important. I dont have 7000 euros for a sigma 800 f/5.6
((

..::SuperBLUE::. wrote:



Zoom with a 2-3X teleconverter is going to look really bad. With smaller
sensors, the optical quality of the lens is MUCH more critical. Something
that was just so-so on 35mm, will probably look like crap on a 1.6-2.0X
factor sensor camera.
--

Stacey

Does sigma 50-500mm f/6.3 with 2x tc look like crap?
Where is the limit where "crap" starts to happen?

..::SuperBLUE::. wrote:

Does sigma 50-500mm f/6.3 with 2x tc look like crap?

Well it's a SUPER wide range zoom with a 2X converter, probably not a good
one so yea, I bet it will be pretty bad.


Where is the limit where "crap" starts to happen?

?? If you want decent quality with a TC, especially a cheap one, stick with
prime lenses. I had OK luck years ago with a 400mm tokina with a 2X
converter, wasn't great but was usable.

--

Stacey

..::SuperBLUE::. wrote:
How does pixel density influence the resolution at super telephoto?
For example: Is it better to buy a:

1. Nikon 8800 with a teleconverter
2.Olympus e300 2x crop factor
3.Canon 350d 1.5 or 1.6 crop factor
4.Panasonic FZ20 with a 2.8/420mm x teleconverter?
5.7mpix consumer camera disassembled and lens replaced with a 35mm slr lens

Lens options:
1.Opteka/Exakta/Samiyang/Vivitar/whatever 650-1300mm f/8-f16 lens (1300mm
f/8 EFL Olympus) (teleconverter???) 250 Eur
2.100-400 f/5.6 with 1.4x teleconverter 500 Eur
3.80-200 f/2.8 Tamron or Tokina with a 3x Kenko teleconverter 600 Eur + 250
Eur
4.600 mm f/8 mirror
5.50-500mm f/6.3 Sigma with 2x and 1.4x teleconverters
6. A diy project of makeing the lens myself from components (found a front
lens 17cm diameter)
7. A telescope with an adapter 6 inch 1200 f/8 refractor 500 Eur + adapter

My goal is to get an image similar to the one from 20x50 binoculars or
better.
50mm lens is normal 1x, then 1000mm is 20x normal???

Thanks in advance.





I'd agree that 1000mm is about 20x for a normal 35mm film format but the
issue is more about field of view. What is the field of view for the
20x50 binoculars you are trying to emulate?

I consider a normal lens to be 1.4x the longest dimension of the image
area. For 35mm that is 36 x 1.4 = 50.4mm as normal. For 4/3 it would be
25.2mm. A 500mm lens on a 4/3 sensor is about 20x but the field of view
may not be similar enough to a wide angle binocular for you needs.
Experiment or research...

-Guy

In message ,
Stacey wrote:

Zoom with a 2-3X teleconverter is going to look really bad. With smaller
sensors, the optical quality of the lens is MUCH more critical. Something
that was just so-so on 35mm, will probably look like crap on a 1.6-2.0X
factor sensor camera.

That depends on the lens. Some can just barely deliver what the sensor
can resolve, some fail to meet that, and others can be magnified 2 to 3
times, and still have pixel-to-pixel contrast that is respectable. The
spacing of the pixels is more relevant than the number.
--


John P Sheehy

In message ,
".::SuperBLUE::." wrote:

Does sigma 50-500mm f/6.3 with 2x tc look like crap?
Where is the limit where "crap" starts to happen?

I had one of these for two weeks before returning it. It was not
TC-able at all, IMO. At 500mm, the lens was already more limiting than
the sensor. All 2x500mm shots were very soft, regardless of stopping
down or using extreme shutter speeds. I would consider this lens a good
50-375mm zoom, with some extra empty magnification up to "500mm". I
really liked the ability to do scenics and birds with the same lens, but
it is *heavy*. I'm much happier with the Canon 100-400; it's 2/3 the
weight, has IS, and can use a 1.4x or even a 2x if stopped down a bit in
very bright light (no AF, though).
--


John P Sheehy

In message ,
Stacey wrote:

?? If you want decent quality with a TC, especially a cheap one, stick with
prime lenses. I had OK luck years ago with a 400mm tokina with a 2X
converter, wasn't great but was usable.

You have to realize that a 2x will use up a lot of light. You need to
halve the exposure time, for the same image stability, and you need 2
stops more to get the same exposure.
--


John P Sheehy