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Jonathan
05-11-2005, 03:55 AM
Hi all. I'm trying to find info on how the film lenses differ from the ones made specifically for digicams.

I have been looking at the Nikon 70-300 G lens and also the DX 55-200 G lens. Is the reach on the film lenses affected due to the size of the image sensor? Other differences? Any help or links is appreciated.

cwphoto
05-11-2005, 07:12 PM
The image circle on digital-only lenses is reduced to correspond with the size of the sensor.

Balrog
05-12-2005, 08:59 AM
"Digital-only" lenses take advantage of the fact that the size of the digital image sensor is smaller than regular 35mm film .. they do not have to project such a large image circle, and so they are typically smaller / lighter than equivalent focal length film lenses.
You can typically use film lenses on digital SLRs with no problems, but the digital ones won't work on film bodies (or will have massive vignetting...)

Ant
05-12-2005, 09:32 AM
I have been looking at the Nikon 70-300 G lens.....

Don't get this lens. It's performance is not great. You can get the Sigma 70-300 APO for only a little more and you'll get better quality out of it.

Jonathan
05-12-2005, 03:56 PM
In the back of the D70 owner's manual, it says that a 300mm film lens will have a 450mm approximate focal length on the D70. As a serious SLR newbie, does this mean that if I used the same lens on a film vs a dig camera, it will seem to zoom farther on the digital, or have I mixed that all up?

Also, do the lenses by the other manuf. support all of the same functions as the Nikon lenses?

D70FAN
05-12-2005, 04:25 PM
In the back of the D70 owner's manual, it says that a 300mm film lens will have a 450mm approximate focal length on the D70. As a serious SLR newbie, does this mean that if I used the same lens on a film vs a dig camera, it will seem to zoom farther on the digital, or have I mixed that all up?

Also, do the lenses by the other manuf. support all of the same functions as the Nikon lenses?

Most dSLR's have a crop factor. This is due to the sensor being smaller than a 35mm film frame. Yes, there are 35mm sized sensors in dSLR's. Yes they are expensive.

The crop factor on the D70 (and most Nikon dSLR's) is 1.5X. This means that a 50mm lens has a new equivalent focal length of 75mm on the D70. On a 35mm film camera the lens is still 50mm.

So whatever it says on the lens just multiply it by 1.5 when you attach it to your D70. So the 18mm-70mm kit lens is now a 28mm to 105mm equivalent on the D70.

You loose on the wide angle end and gain on the telephoto end. Bad if you shoot real estate... good if you shoot nature, sports, and wars.

P.S. Take Ants advice and spend a few dollars more on the Sigma 70-300 APO (not the DL!!!). On the D70 it will be a 105mm-450mm lens.

Jonathan
05-13-2005, 06:31 PM
You loose on the wide angle end and gain on the telephoto end. Bad if you shoot real estate... good if you shoot nature, sports, and wars.

P.S. Take Ants advice and spend a few dollars more on the Sigma 70-300 APO (not the DL!!!). On the D70 it will be a 105mm-450mm lens.

That helps! Thanks! :)