Sensors and Cameras

[domu221]

Hi guys, I need your help once again with something technical!

So I understand that cameras with full frame sensors have frames equivalent to that of a 35mm film camera. And that it's expensive to make a full frame sensor so a lot of consumer dslrs are made with the APS-C sensor that has a crop factor (for example with Nikon's DX lineup, 1.5x the full frame sensor).

But my question is, do camera manufacturers use the same sensor for different cameras? Like do Nikon DX cameras have the exact same APS-C sensor?

 

[Solarflare]

The most important factor with growing size of the fotosensor is AFAIK the lens.

If you double the size of your fotosensor, you get four times the fotosensor area, but the weight of the lenses (if they stay exactly the same, just bigger) is 8 times as high.

 

[jaomul]

The most important factor with growing size of the fotosensor is AFAIK the lens.

If you double the size of your fotosensor, you get four times the fotosensor area, but the weight of the lenses (if they stay exactly the same, just bigger) is 8 times as high.

Check your maths again

 

[Solarflare]

Its most basic geometrics, so nothing to check there.

 

[Buckster]

Its most basic geometrics, so nothing to check there.

Lenses for use with medium format digital are not bigger than those for full frame, and full-frame lenses are not bigger than lenses used with crop-frame cameras.

The same was and is true for film. 35mm, medium format, large format - lenses were not necessarily bigger for each larger format.

 

[snowbear]

As to your question on sensors: Some, but not all DX camera models use the same sensor. Some models also share autofocus systems.

 

[Buckster]

But my question is, do camera manufacturers use the same sensor for different cameras?

Sometimes, mostly based on whether they're being manufactured in the same generation (time frame) and whether they are in the same basic class with each other. To find out which ones use the same sensors, you'd have to do some comparisons. www.dpreview.com is a good place to find out such details.

 

[jaomul]

Its most basic geometrics, so nothing to check there.

If you double the size of your sensor you get 4 times the area? How does this work. A FF sensor is approx double the size of a crop and guess what, it is not 4 times the area. Did you just make this up?

 

[Dao]

The most important factor with growing size of the fotosensor is AFAIK the lens.

If you double the size of your fotosensor, you get four times the fotosensor area, but the weight of the lenses (if they stay exactly the same, just bigger) is 8 times as high.

Do you really mean double the "[FONT=Verdana, Arial, Helvetica, sans-serif]Length & Width"[/FONT]?



Let's see the real life example.

Nikon D4 sensor size: 861.6 mm sq
Nikon D7000 sensor size: 368.16 mm sq

So the size increase is about 2.3x


As for the weight of the lens, why do you think it is 8 times high?

 

[cgipson1]

The most important factor with growing size of the fotosensor is AFAIK the lens.

If you double the size of your fotosensor, you get four times the fotosensor area, but the weight of the lenses (if they stay exactly the same, just bigger) is 8 times as high.

What????? Sorry.. but that makes no sense at all!

 

[Solarflare]

Its most basic geometrics, so nothing to check there.

Lenses for use with medium format digital are not bigger than those for full frame, and full-frame lenses are not bigger than lenses used with crop-frame cameras.

The same was and is true for film. 35mm, medium format, large format - lenses were not necessarily bigger for each larger format.

Well - thats because they stop growing with the format, though.

Its especially obvious with large format where the lens may be much smaller than the film.

But even for medium format its already noticeable. No more f/1.4, f/1.2 or even f/0.95 primes. Instead we get a Planar 80/2 for the Contax 645 and a SUMMARIT-S 70 mm f/2,5 for the Leica S2 (both are the closest equivalents for 50mm on full frame).

As a result, the apertures available for medium and large format are increasingly smaller.

 

[KmH]

But my question is, do camera manufacturers use the same sensor for different cameras? Like do Nikon DX cameras have the exact same APS-C sensor?

Yes.

Nikon's D5100 and D7000 share the same image sensor. That image sensor is made by Sony for Nikon and is also used in the Sony A-55.

Nikon's D90 and D300/D300s share the same image sensor.

 

[domu221]

Sometimes, mostly based on whether they're being manufactured in the same generation (time frame) and whether they are in the same basic class with each other. To find out which ones use the same sensors, you'd have to do some comparisons. www.dpreview.com is a good place to find out such details.

Thanks for the link, I use that site to compare lenses!

You mentioned that it's mostly based on the time they're being manufactured. Does that mean that the D300s has the same sensor (or slightly similar sensor) as the old entry level D3000?

I started this thread cause it really really bothers me that entry-levels cant take sharp, good pictures because of their sensors are very limited. OK OK, I know this is somewhat wrong but I keep thinking that an entry level camera cant do something the D300s can because of its sensor in the DX camera line. In other words, i keep thinking that cheap cameras cant take pics like an expensive cameras can.

Also, Solarflare. Can you please tell me what you mean by your first response, that the lens is the most important factor of a growing sensor? Thanks again!

 

[480sparky]

If you double the size of your sensor you get 4 times the area? How does this work. A FF sensor is approx double the size of a crop and guess what, it is not 4 times the area. Did you just make this up?

I think he means double both dimensions.

If you have a 1" x 1" sensor, you have one square inch. Double both dimensions to 2" x 2", and you have four square inches.




Now if you could get an explanation about how the weight of lenses factor into it.........

 

[Dao]

Yes, the entry level dslr camera cannot do something that D300s can, but it is not image quality. As for sensor used in different models, the answer is yes, different models may share the same sensor. Just like automaker, different car models use the same engine models. Some even used in different car brands.

My advice is do not think too much.