DX body vs DX mode in FF body

[RichF]

Is there any advantage to a DX body versus using DX mode in a FF body? Let's assume that the number of pixel in both cases is relatively similar.

Obviously the DX body will cost less and the FF body gives you the option of shooting both DX and FX modes and may have higher video capture model (4K vs HD or 8K vs 4K).

Thoughts? I am missing something - is there is any advantage to a DX body beside costs?

 

[bleirer]

No benefit that I know of to using the dx if the fx in crop mode is the same resolution. More flexibility with the fx of cropping any amount(not required to go all the way to DX size If not needed for the shot).

 

[Woodyg3]

 

[NorthernFocus]

There is no technical difference. This subject has been discussed ad nauseum in multiple threads re.D500 vs D850. Strong proponents on both sides of the argument.

 

[NorthernFocus]

Video discusses cropping FF images not shooting in crop mode.

 

[NorthernFocus]

Whats the difference?

I’d rather full frame personally and have an option.

And here we go...

Buffer depth, card space, and (on some cameras)fps. It can also be useful to get a sense of how much frame is filled by the subject.

 

[Nimi]

Someone, maybe @arbitrage had mentioned the ease of focus for remote subjects with DX.

 

[NorthernFocus]

Someone, maybe @arbitrage had mentioned the ease of focus for remote subjects with DX.

???

 

[Tom Reynolds]

The Nikon D-850 has approximately the same resolution in DX mode as the D-500. The big edge is that you have a choice of FX or DX. Since you have a larger angle of view in FX mode it is somewhat easier to get the subject in the frame than with the D-500 DX. Also, sometimes 500mm on a crop camera may be too long as it is a 750MM FX equivalent so a subject may be too close in DX mode but not in FX mode.

The flip side is that the DX camera is lighter, cheaper and takes 200 shots without stopping at 10 fps, then takes 200 more if you ease off the shutter even for an instant because the 200 shot limit is a software limitation. The buffer never fills up with an appropriate card installed.

Auto focus is interesting. Most say that the D-850 focuses very slightly faster and does low light a bit better BUT the focus points on the D-500 essentially cover the sensor while they don't on the D-850.

So what about in the field?
Getting a bird in flight in the frame takes practice. While a larger angle of view means that you can find the subject faster you still need to get the subject in the GRP autofocus zone. More significantly, a great shot really needs a SP autofocus on the eye. Because focus points don't fill the frame with a D-850, most photographers use BBAF (Back Button Auto Focus) so they can focus, then recompose. My experience indicates no such need with a D-500 DX as you can move the focus point anywhere on the screen. The result is more practice is required with the D-850 to switch AF modes because there is one more button to push with one more finger. For me the D-500 is a two-finger implementation. One figure on the shutter and the ring finger on the Fn1 button. My thumb is not involved. When the bird takes off, I simply release the Fn1 button and switch from SP to GRP. BBAF is really popular but mirrorless photographers are finding it unnecessary because the focus points cover the screen. The D-500 has the same feature. The result is a tradeoff between a larger angle of view but on a slightly heavier camera, shooting less frames per second with greater dexterity required.

To me, the big advantage is that the D-850 can take closer closer subjects. Using a 500pf, the D-850 has a 500mm and a 750mm equivalent while the D-500 only has the 750mm equivalent. I looked at switching to D-850's for this reason but decided on another solution which brings up another comparison.

Comparing a D850 with a 500PF in FX mode with a D-500 Dx with a 300pf. The D850/500pf has a lot more megapixels (45 vs 21) but the D-500 is a pound lighter and much easier to handle. In fact, catching those flitting birds relatively close in even the GRP AF area is worlds easier with the D-500/300pf. My solution was two camera bodies, one with a 300PF, one with a 500pf. This solution was considerably more costly than either single camera setup but allows me roughly equivalent reach and angle of view of a D-850/500pf at F/4 as opposed to F/5.6. The weight to carry is higher but the weight in the hand is not.

So yes, the D-850 is better in that it is two cameras in one, but it is not better than two cameras that cover the same 500mm, 750mm (equivalent) range most useful for bird photography.

 

[EricBowles]

In a DSLR, the DX bodies usually can have faster frame rate because files are always smaller leading to a faster fast write speed. The other benefit is the AF outlines in the EVF are larger in relative terms when displayed on a DX viewfinder than a corresponding FX viewfinder. In addition, the DX viewfinder is more magnified, so for a distant subject the subject is larger in the viewfinder. DX cameras can be a little smaller than comparable FX cameras. Lenses can be smaller, but it' often not a true comparison because optical performance is different. Finally, the DX cameras are cheaper than comparable FX cameras tht can be cropped to DX proportions.

With a mirrorless DX camera, most of these benefits go away. The EVF of a full frame camera in DX mode would look the same as a DX camera. The only real advantages would be with frame rate and possibly burst length. And of course, cost probably favors DX. Since the full frame cameras are already relatively small, I don't think size make much difference. A full frame mirrorless with a pancake lens or small normal lens is going to be relatively small and light. You just need to choose your gear with size as a priority.

 

[Backdoor Arts]

No benefit that I know of to using the dx if the fx in crop mode is the same resolution. More flexibility with the fx of cropping any amount(not required to go all the way to DX size If not needed for the shot).

In addition to Buffer depth, card space, and (on some cameras)fps as stated by @NorthernFocus, when I have a small bird deep in a tree I'll switch to cropped mode just to help the focus system out a bit, or get the focus point right on it. I'd never use it on a DSLR, but with mirrorless the viewfinder adjusts, which is great for this. Plus, if I'm already going to crop in more than what cropped mode gives me, which happens a lot on small birds, then why shoot a 45MP image?! I have a button set for changing modes, that's how often I use it. I'm on an R5 now but used to shoot almost exclusively with a D500 and I miss the reach a bit.

 

[arbitrage]

Is there any advantage to a DX body versus using DX mode in a FF body? Let's assume that the number of pixel in both cases is relatively similar.

Obviously the DX body will cost less and the FF body gives you the option of shooting both DX and FX modes and may have higher video capture model (4K vs HD or 8K vs 4K).

Thoughts? I am missing something - is there is any advantage to a DX body beside costs?

In the MILC world I wouldn't say much other than cost and maybe video formats as you mention. In the DSLR D850/D500 type comparison I found some more advantages to the DX but also there were advantages to the FX even if not filling the frame past DX.

But with MILC all the FF cameras have a DX mode and unlike on a DSLR, that mode zooms into the DX frame which gives you the benefit of a magnified view, smaller files, deeper buffer and all at the tap of a button (on Sony) or tap and scroll (on Nikon and Canon). On my Sony it is so easy to switch that I've done so mid BIF burst...started tracking and bursting in DX as further away and then tapped my custom button into FF as the bird gets closer. Canon and Nikon are a little more involved so not best to take it to that extreme.

One other advantage I found on both Nikon Z9 and Canon R5 (not so much on A1) is that BEAF activates more often if you switch into crop mode (if it hasn't already activated in FF). I assume this is just concentrating the AI power into a smaller area of the frame and making the bird bigger in the frame.

 

[RichF]

Thanks for all the helpful comments. Pretty much as I suspected, in MILC little advantage to a DX camera. I have not tested the Z9 in DX mode but I hope in a future firmware release Nikon will give us 30 FPS (or higher) raw in DX mode. Plus the number of shots will dramatically increase before the buffer fills.

 

[Roy]

Is there any advantage to a DX body versus using DX mode in a FF body? Let's assume that the number of pixel in both cases is relatively similar.

Obviously the DX body will cost less and the FF body gives you the option of shooting both DX and FX modes and may have higher video capture model (4K vs HD or 8K vs 4K).

Thoughts? I am missing something - is there is any advantage to a DX body beside costs?

I dont see any advantage except price.
My D500 has just been retired because my D850 bodies and Z9 suit my needs better...

 

[Backdoor Arts]

Thanks for all the helpful comments. Pretty much as I suspected, in MILC little advantage to a DX camera. I have not tested the Z9 in DX mode but I hope in a future firmware release Nikon will give us 30 FPS (or higher) raw in DX mode. Plus the number of shots will dramatically increase before the buffer fills.

That's an "all other things being equal" assessment. You give me a 24-30MP DX camera and I'm getting more pixels per bird than I would with any of the current big sensor full frame cameras. I get 17.3MP's on my R5. If they introduce an R7 that's a cropped sensor in the 24-30 MP range I am surely going to consider it as a second camera provided that it matches the frame rate and focus ability I can get on the R5. It would never replace the R5, but it would likely be my main camera in certain situations.

 

[bleirer]

That's an "all other things being equal" assessment. You give me a 24-30MP DX camera and I'm getting more pixels per bird than I would with any of the current big sensor full frame cameras. I get 17.3MP's on my R5. If they introduce an R7 that's a cropped sensor in the 24-30 MP range I am surely going to consider it as a second camera provided that it matches the frame rate and focus ability I can get on the R5. It would never replace the R5, but it would likely be my main camera in certain situations.

I find the future R7 a very enticing "only" camera. Let's say there is a R7 with 30mp vs a future R relacement at 30 mp but full frame. What would your opinion be about the pros and cons of that decision.

 

[Backdoor Arts]

I find the future R7 a very enticing "only" camera. Let's say there is a R7 with 30mp vs a future R relacement at 30 mp but full frame. What would your opinion be about the pros and cons of that decision.

I've yet to find a situation where 20fps is utterly insufficient. I understand how those extra 10 add value, just as I was OK at 11fps before I could get 20. For me, reach > frame rate for my type of shooting, which is largely smaller birds at a distance. If frame rate was more important I'd be on an R3 list. I'm guessing having spent 5 years with a D500 as my main camera impacts my worldview on this. But given some of the things I've been shooting lately with the R5, I'm more apt to stick with that as #1, particularly if the R7 is more akin to the R6 ergonomically, as I've gotten incredibly used to it.

 

[Calson]

When the D500 became available it provided the new autofocus system with the dedicated AF chip and was at a third the cost of a D5 and so a good value. But when photographing birds in flight with a telephoto lens the frame was very tight and it was common to cut off part of a bird or have them right at the edge of the frame and no breathing room around them.

With the D850 even in DX mode I still had the full frame of a FX camera but most of the time I still shot in FX mode and cropped later to get optimum placement of the flying bird in the frame. The faster the bird the more difficult I have found to get it properly positioned in the frame. The advantage of the D850 was that in DX mode I still got a 19MP image to use as compared to less than 9MP with a D5/D6/R3 camera which is designed for sports shooters.

 

[LL4D500]

The Nikon D-850 has approximately the same resolution in DX mode as the D-500. The big edge is that you have a choice of FX or DX. Since you have a larger angle of view in FX mode it is somewhat easier to get the subject in the frame than with the D-500 DX. Also, sometimes 500mm on a crop camera may be too long as it is a 750MM FX equivalent so a subject may be too close in DX mode but not in FX mode.

The flip side is that the DX camera is lighter, cheaper and takes 200 shots without stopping at 10 fps, then takes 200 more if you ease off the shutter even for an instant because the 200 shot limit is a software limitation. The buffer never fills up with an appropriate card installed.

Auto focus is interesting. Most say that the D-850 focuses very slightly faster and does low light a bit better BUT the focus points on the D-500 essentially cover the sensor while they don't on the D-850.

So what about in the field?
Getting a bird in flight in the frame takes practice. While a larger angle of view means that you can find the subject faster you still need to get the subject in the GRP autofocus zone. More significantly, a great shot really needs a SP autofocus on the eye. Because focus points don't fill the frame with a D-850, most photographers use BBAF (Back Button Auto Focus) so they can focus, then recompose. My experience indicates no such need with a D-500 DX as you can move the focus point anywhere on the screen. The result is more practice is required with the D-850 to switch AF modes because there is one more button to push with one more finger. For me the D-500 is a two-finger implementation. One figure on the shutter and the ring finger on the Fn1 button. My thumb is not involved. When the bird takes off, I simply release the Fn1 button and switch from SP to GRP. BBAF is really popular but mirrorless photographers are finding it unnecessary because the focus points cover the screen. The D-500 has the same feature. The result is a tradeoff between a larger angle of view but on a slightly heavier camera, shooting less frames per second with greater dexterity required.

To me, the big advantage is that the D-850 can take closer closer subjects. Using a 500pf, the D-850 has a 500mm and a 750mm equivalent while the D-500 only has the 750mm equivalent. I looked at switching to D-850's for this reason but decided on another solution which brings up another comparison.

Comparing a D850 with a 500PF in FX mode with a D-500 Dx with a 300pf. The D850/500pf has a lot more megapixels (45 vs 21) but the D-500 is a pound lighter and much easier to handle. In fact, catching those flitting birds relatively close in even the GRP AF area is worlds easier with the D-500/300pf. My solution was two camera bodies, one with a 300PF, one with a 500pf. This solution was considerably more costly than either single camera setup but allows me roughly equivalent reach and angle of view of a D-850/500pf at F/4 as opposed to F/5.6. The weight to carry is higher but the weight in the hand is not.

So yes, the D-850 is better in that it is two cameras in one, but it is not better than two cameras that cover the same 500mm, 750mm (equivalent) range most useful for bird photography.

Really appreciate your explanation!

 

[splatbass]

The last couple of years I've been using a D850 for wildlife, and I go into DX mode quite a bit. But recently I bought a Z50 to have a small lightweight carry around camera. Lately I've been using it a lot for wildlife instead of the D850, mainly for two reasons - when I hike the Z50/500 PF combo is lightweight but still powerful, and for birds I like the silent shutter (in a quiet forest the D850 sounds like a machine gun going off...). At any rate, I don't see any difference in quality between the FF in DX mode and the DX. I like having both options.

 

[Roy]

The last couple of years I've been using a D850 for wildlife, and I go into DX mode quite a bit. But recently I bought a Z50 to have a small lightweight carry around camera. Lately I've been using it a lot for wildlife instead of the D850, mainly for two reasons - when I hike the Z50/500 PF combo is lightweight but still powerful, and for birds I like the silent shutter (in a quiet forest the D850 sounds like a machine gun going off...). At any rate, I don't see any difference in quality between the FF in DX mode and the DX. I like having both options.

Have you tried the D850 in silent mode?

 

[splatbass]

Have you tried the D850 in silent mode?

Yeah, it is only silent in Live View, which I don't really use for wildlife.

 

[Anjin San]

Is there any advantage to a DX body versus using DX mode in a FF body? Let's assume that the number of pixel in both cases is relatively similar.

Obviously the DX body will cost less and the FF body gives you the option of shooting both DX and FX modes and may have higher video capture model (4K vs HD or 8K vs 4K).

Thoughts? I am missing something - is there is any advantage to a DX body beside costs?

Depending on the exact pixel size and pitch in the two bodies…there might be a slight advantage to one of the alternatives since bigger pixels with bigger pitch generally means less noise and more light gathering which means better IQ. However…unless you do the math and check the sizes it's not really easy to figure out. Generally speaking…the crop sensor body tends to be slightly smaller pixels at closer pitch to keep it's MP at 20 or above as compared to the larger FF sensors but it's not universally true. In addition the difference is pretty small anyway and for most normal purposes you won't really see much IQ difference at all…and whatever slight there might be is counterbalanced by the smaller body and the need to not carry 2 bodies to have both formats in hand in the field. What you do with your output is also a major consideration here…for display on screen you'll be hard pressed to see any difference.