Question about DX and FX

Blake.Oney · Sep 11, 2010

I was watching one of those Froknows videos and he mentioned that DX lenses are not good with FX cameras, but FX lenses are amazing with DX cameras. I am kind of concerned with this. I wouldn't be if I had the cash or what I thought was the skill level to go straight to a full frame camera, but I don't. My next camera will most likely be a D90/7000(or whatever the replacement name is) or a D300s. So that will put me at having a few years on the DX system, and hopefully multiple lenses.

Now once I get my next camera I will most likely be buying almost all FX lenses anyways since it will have internal AF, but the few lenses that I have or will get that are DX, like the ones I have now, and soon the 35mm f1.8, and possibly the 18-200 VR, will they be okay to use with a full frame? Or will they effectively leave my collection on the day that I do upgrade to FX?

sobolik · Sep 11, 2010

Blake.Oney said:
I was watching one of those Froknows videos and he mentioned that DX lenses are not good with FX cameras, but FX lenses are amazing with DX cameras. I am kind of concerned with this. I wouldn't be if I had the cash or what I thought was the skill level to go straight to a full frame camera, but I don't. My next camera will most likely be a D90/7000(or whatever the replacement name is) or a D300s. So that will put me at having a few years on the DX system, and hopefully multiple lenses.

Now once I get my next camera I will most likely be buying almost all FX lenses anyways since it will have internal AF, but the few lenses that I have or will get that are DX, like the ones I have now, and soon the 35mm f1.8, and possibly the 18-200 VR, will they be okay to use with a full frame? Or will they effectively leave my collection on the day that I do upgrade to FX?

The DX will be no good on a FX but on the other hand you can spend the rest of your life very very happy using DX camera and lenses. The D90 could very well last you and your kids life time. (assuming no breakdown or radical change in technology) I have a D-90 and the only reason I would upgrade would be for more megapixals since I crop very small sections out to make 4x6 prints. Otherwise the D-90 is overkill for the vast majority of peoples needs. I forgot the % but many people don't even make prints anymore.

Lenses can be flawed on the perimeter of the image they impose on the film or sensor. On the other hand probably 99.9% of the human population never notices these flaws. Using a FX lens on a DX sensor means that the "flawed" perimeter is never even imposed on the sensor. Only the center of the image is imposed on the sensor. Using a DX lens on a FX film or sensor means that the perimeter lies more toward the center and does not even fill the film or sensor area.

I have no intention at this time to go to a full frame digital camera. My 12mm DX lens is equivalent to a 18mm Film (FX) lens. That width is plenty good. My 18-200mm lens at 200mm is equivalent to 380mm and plenty good enough. I don't make anything over 8x10 prints anyway. Even with my cropping tiny sections out of the photo capture I find no attraction to full frame or FX.

Blake.Oney · Sep 11, 2010

That makes sense. I do a little more than hobby photography at the moment and I plan to grow, but the most I ever plan on doing is more of what I'm doing now. That is getting paid for mostly portraits or events. So it does make sense that I would never really need anything more than a D300* or whatever replacements it has in the future and really good glass.

ann · Sep 12, 2010

saying a DX lens is No good on an fx camera is not quite correct.

one can use a dx lens on a nikon for instances and the camera will automatically cropped the image to use only the center of the sensor i.e. aps size and of course there is a reduce in the pixels uses, but the image can be of high quality

Blake.Oney · Sep 12, 2010

Yea, but wouldn't that be pretty undesirable unless you were in a pinch and really really needed a certain lens and the closest thing to it was a dx lens?