FX or DX?
 

I had posed a similar question on another forum and thought I should try it on this forum since Nikon seems to be active in development of both DX and FX cameras.

Nikon continues to prioritize its high end lenses in the FX mode with the exception of perhaps the 17-55 f/2.8. Therefore if one is looking to buy good glass, should one be concerned that DX lenses will for the most part be limited to consumer level lenses? I guess I'm trying to read the tea leaves and decide between getting a 17-55 f/2.8 or the 24-70 f/2.8 for a D300s. I realize there is about a $500 premium for the latter. I already have a 12-24 f/4.

You may also want to look at the newer Sigma 24-70mm f/2.8 EX DG HSM. You can see a review comparing it to the Nikkor lens here, using a Nikon D200 for the APS-C comparisons, and a Nikon D3x for the full frame comparisons:

http://lenstip.com/172.4-Lens_review...esolution.html

FX are design for full frame, DX on a full frame will require you to crop the sensor. If you think you will go full frame in the future, get a FX instead. If you plan to upgrade say a D700 in the future. Get a FX lens instead. That way you get to use the whole ff sensor.

Some DX lenses are very good and some are not so good.

Some FX lenses are very good and some are not so good.

Don't try to make a distinction on quality based on the size of the image circle. Use objective test results like those on SLRGear.com and PhotoZone.de instead.

Aren't you going the wrong way? While the 17-55 calculates to the equivalent of a 25-82FX lens, placing the 24-70FX lens on a DX body, such as the D300 would be the equivalent coverage of 36-105. That would be quite a gap giving up considerable wide angle.

Wouldn't the more equivalent FX lens be the 14-24 f2.8? with 21-36 coverage? Of course, if you upgraded to an FX body, you would have an ultra wide zoom, and would still have to get the 24-70FX as a standard zoom.

You are correct in the translation of the focal length on a DX vs a FX. However, in my case, I own a 12-24 already. So a 24-70 would suit me fine. My question had more to do with whether DX will eventually go away with the proliferation of FX sensors.

Absolutely not. APS-C dSLRs are smaller, lighter, and less expensive that 'Full Frame' dSLRs, and that will always be the case. Plus APS-C dSLRs have a greater selection of lenses that 'Full Frame' dSLRs have, and those lenses are smaller, lighter and less expensive as well, making them a more attractive purchase. There are reasons to get a 'Full Frame' dSLR, but for the vast majority of people, those reasons don't apply.

And make no mistake, FX sensors aren't proliferating nearly as fast as DX sensors.

Well tube televisions used to be mainstream too.

Tube televisions have been replaced by LCD/Plasma technology. Today's tv's take up much less space than the old tube TV's. You're comparing apples to oranges. DX is going nowhere anytime, simply because there are many advantages to the format. It's smaller, lighter and much cheaper, all things that are desirable to the vast majority of photographers. I think FX/Full frame is comparable to medium format in the film era. If anything, I think DX is more threatened by m4/3 or other larger sensor in small format cameras than by FX.

They're not still mainstream? :(:D

Actually, we still have a 36" Toshiba TV (tube type) in our Den. It still works just like new (no problems at all, with great picture quality), even though we've had it for a number of years. I don't watch TV very much, so it's not a big deal for me if I don't have a newer 1080p compatible wide screen display. I'm more likely to use my PC screen (LCD) for watching TV shows than I am sitting in our den anyway. lol