New Equipment

[skitterbug]

I've reached a time when I can invest in new equipment ($2500 more or less depending). So I've a couple of thoughts to ask about before trying to decide. My Rebel is a crop camera and I have the two kit lenses for it. So I figure I can go any direction without feeling the need to put the current equipment in the mix with the new.

I think a full frame camera might be a treat to have be it Nikon or Canon? or are the crop frame ones a better choice? How to decide?

And then, would it be best to purchase the body and then decide on a lens or two as a separate purchase? Or are the kit lenses fairly decent?

I know my current lenses do okay but I would have appreciated a macro lens and another that did reach out there a bit more. Of course I didn't know this when beginning my photography adventure. The camera I moved from was a digital point and shoot so I was a "raw" beginner. I feel I am a step or two above that level now.

There are "sales" going on now or is it better to wait until after the new year begins? Anybody's guess about this one I suppose.

So I am curious what anyone may have to say on this topic. It has probably been hashed over before many times but there may be new opinions to be offered.

Thanks in advance for any ideas!

Merry Christmas! The Holidays will be here before we turn around twice! Enjoy!

[Manfred M]

The one question I ask anyone who is looking at upgrading their camera system is "what are you not able to accomplish with your current equipment that the upgrade will do for you". If the answer is "nothing", save yourself a lot of money and invest it in something else that will give you greater value for your money.

The other question would be, where do you want to head with your photography? Again, answering that question would give you a lot of the answer on where to spend your money.

I do a lot of large format prints (17" x 22"), so I can rationalize going to a full frame camera from that standpoint. If all you want to do is the occasional print, then I see no advantage of going full frame for you; a crop frame camera has more than enough resolution for anything you might view on a screen or post on the internet. I'm also someone who does a lot of shooting at full aperture to get a very narrow depth of field; so high speed lenses (apertures of f/2.8 or less) on a full frame camera will deliver that; but a single fast zoom lens with a maximum zoom factor of around 3x will blow your entire budget, without including the camera body.

[DanK]

Sandy,

It's really hard to answer this unless you say more about what kinds of photography you want to do most and in what ways your current equipment is holding you back. However, I'll offer a few thoughts, for what it is worth.

Nikon sensors are somewhat better right now, but IMHO, for most people, it makes no difference which you buy. I am entirely unable to figure out which brand people use when they show me photos. And the cameras that both companies offer now are better than those that either one offered not long ago.

One advantage of Canon for you is that would would be able to continue using all of your current equipment, with the exception of EF-S lenses if you buy a full frame camera. EF-S lenses which have too small an image circle for full frame cameras.

Re full frame: it's not a treat, it's just a different choice. FF cameras are bigger, heavier, generally more expensive, and require bigger and more expensive lenses. (More on that in a moment.) the main advantage of FF, IMHO, is that all other things being equal, they handle low light better. If you print VERY large and have good enough lenses, they also can provide more detail. For most people much of the time, it doesn't make any practical difference.

Re lenses: You need a longer lens to fill the frame with a FF camera than with a crop. that is, you get less reach with a FF. People will respond that you can crop an image from a FF camera to get the same image you would get from a crop with the same lens, but since most FF cameras have lower pixel density (which is the major reason they handle low light better), you end up with fewer pixels in the image if you crop FF in this way. My main camera is a Ff 5DIII, which I love, but when I want reach--for example, when I go to a nearby bird refuge--I take my refurb 7D instead. I also use it for bug macros (but not for flower macros, for which reach is rarely an issue). Since you mentioned wanting more reach...

Given your budget, you might want to consider factory refurbished equipment. In the case of Canon, you can get this from their own website, but other vendors, e.g., Adorama, sometimes have some as well. I have purchased one body and two lenses this way, and all have been like new. Canon runs periodic sales of refurbished equipment, but you just have to watch for them, and they often sell out. For example, right now, Canon's price for a refurb 7DII is $1199, marked down from $1439. The same body is $1949 at B&H, where I buy most of my equipment.

Re macro lenses: virtually all of the major ones are tack sharp. the biggest consideration is the focal length you want. I mostly use 100mm and have the Canon L version, but the non-L version is optically similar and much cheaper. Some folks here use Sigma and tamron macros and can report on their experiences, but I think most of the comments have been positive.

So, all in all, I'd step back and ask: what would you most like new equipment to do for you? If you want better ergonomics and want to stay with Canon, you need to step up from the Rebel line, but there are a lot of choices above that: the xxD and 7D crop lines and the 6D and 5D FF lines. As you move up that ladder in cost, you will forgo other things, like lenses, so higher up the food chain isn't necessarily better all in all.

[Shadowman]

Hi Sandy,

Happy Holidays1

The typical questions usually arise when someone posts this type of inquiry.

1. Any reason your current camera can't still be utilized? I've used the T3i for work (still life, a few passport style portraits) and I never liked the color or detail of the Rebel, however most images were taken under fluorescent lighting so experience is limited. Have you ever used the camera with external flash, sometimes lighting can add a different feel to an image. I usually shoot Nikon and have one lens (55-200) that I was never satisfied with the output; added flash to some images and found a new life for the lens.

2. Have you tried other lenses with your kit?

3. Have you looked at other crop sensor Canon models?

4. Is FF the only option you are willing to explore, have you looked at the mirrorless systems yet?

Just a few thoughts regarding your move to the next system.

[rpcrowe]

Sandy,

A few questions might help us point you in the best direction...

1. What type or types of photography are you interested in?

2. What do you expect that your final products might be: prints, Internet posting, etc?

3. What is your experience in digital or film photography?

4. What short comings do you see in your present Rebel camera and kit lenses?

A few random observations all of which are my opinions. I am simply giving my opinion regarding equipment. Obviously the skills and talent of the photographer is the deciding factor in achieving good imagery. My answers are going to go along Canon lines because those are the cameras I have all my digital experience with. I also will go along DSLR rather than mirrorless lines because I generally use only DSLR equipment.

While full frame cameras are nice, crop cameras are perfectly able to capture excellent imagery. Crop cameras are often lighter in weight and the cameras and lenses can be a lot less expensive than full frame models.

Lenses are, IMO, the key equipment ingredient in the good image recipe. A good lens on a less capable camera can give better imagery than a lesser lens on a top line camera. However, I personally would not go with an entry level Canon Rebel camera because I really like the two dial controls of the xD and xxD type cameras. IMO they are easier and a lot more fun to use because you can control many of the camera parameters without going into the menu.

As far as lens compatibility within the Canon line (I am really not all that familiar with Nikon gear), full frame cameras can only accept EF lenses while crop cameras can accept both EF and EFS lenses.

If I were starting to build my photo equipment, I would probably begin with a Canon crop camera. I would add a mid-range zoom lens with a constant f/2.8 aperture and a telephoto lens of a 70-200mm or 70-300mm focal range. This would put you on a solid footing. I shoot 90% of my images with either a 17-55mm f/2.8 IS lens or a 70-200mm f/4L IS and would feel comfortable. I do quite well in available light with my f/2.8 lens because of its great image stabilization.

A macro lens could be added to the mix. I prefer a macro in the focal range or from 90-100mm, although there are several shorter macro lenses available. Often, however, shooting with a short macro lens forces you to be too close to your subject. No problem for flowers or other inanimate subjects but inconvenient when shooting creepy-crawlies...

There are other factors which can be added to the mix:

OEM or third party lenses... There are many great lenses made by third party manufacturers such as Tamron and Sigma as well a a few duds produced by Canom. The 75-300mm IS lens is one of these duds.

New or used... I have purchased several lenses new and several from the used market. I would recommend that a fairly inexperienced photographer stick with new lenses. However, I have purchased most of my cameras as Canon refurbished items and have always been happy with them.

Body alone or body + lens. While generally, kit lenses are pretty decent, I would suggest buying a body and equipping it with the lenses I have chosen.

There are lots of sales going on now. I recommend that you peruse the equipment offered by B&H (https://www.bhphotovideo.com/) or Adorama (https://www.adorama.com/?gclsrc=aw.d...hoCsowQAvD_BwE). I have purchased numerous cameras and lenses from these two dealers and have always been happy. Most of the time, shipping is free and state tax is not collected.

I would recommend adding a hotshoe flash to your kit!

Finally, when you buy your new kit, think about keeping the Rebel as a second or backup camera.

[miatab]

There is a wealth of sincere, honest sensible advice here from people who know more than we will ever know. Be guided by what they have said and save money and heartache. The wonderful thing about this pro advice is that they are not trying to sell you a new camera and trying to separate you from your $2500 hard earned bucks. They will welcome your future questions, but listen to them; this is a learning forum and they are expert teachers.

[skitterbug]

I'm going to try and answer in one post! Hope I don't ramble or repeat (very often - lol)

Manfred - So starting with the "why"... I knew when I got the Rebel, it was really a beginning to a more serious digital effort for my photo hobby. The camera has been useful and I've learned a lot. And yes, I know that good pics can be taken with "any" equipment so long as the operator knows how to use the equipment.

A problem I have with my Rebel is that it doesn't seem to be sealed very well. It tends to draw moisture far quicker than I would expect a camera to do. I go through the stages of acclimating it to colder conditions by putting it on the side enclosed porch area and from there heading outside for winter shots. Before I realize it, I'm trying to get photos and instead of good results, there is a haze developing on my pics. It is frustrating. I'm hoping newer equipment will eliminate this problem.

I'm not looking for wi-fi connections or better video capabilities (though that might be nice for quick, short takes). I'd like to be able to take crisper, clearer shots. I think the newer technology may be helpful. I have the chance to upgrade and I may not get another. Age and resources make a difference.

I will print a photo from time to time but I've not "gone fancy" with my prints - yet. It is something that you've made me consider though! I have the old trunk of family photos and I do enjoy looking at them. A digital photo on a screen doesn't always do the subject the justice it may deserve.

Dan - As you pointed out, if I stay with Canon cropped frame, I could use my current lenses with the new purchase so that is something to consider. And you also brought out that the FF weighs more than the cropped one does. Heavier gear over the course of a day would make a difference to me.

I've considered the idea of refurbished equipment but I'm hesitant to go that route. I've purchased computers that way because I knew I could fix them if there was a problem. For a camera, I'd be at the mercy of the company so I believe I'd be better off with new stuff.

John - Yes, happy Holidays!
Now I hope that my replies make sense to you?
1. The why for a change from my current equipment is incorporated into my previous replies, I hope.
2. No, I didn't want to put more expense into my current kit by adding to it until I'd made a decision about what I'd want.
3. Well.... I've looked at Canon models but there are so many choices. Same with Nikon. And that's why I decided to start asking for opinions.
4. I was thinking between FF and cropped systems. I've not looked at mirrorless systems.

Hi Richard - First thing, I'm glad that you are safe from those terrible fires. It is sad reading about all those affected by them.

Now for answers:
1. I tend to take some landscape shots but more likely, I am after birds, kid's sports, family activities, buildings, planes flying overhead, etc. I would also want to take group shots from time to time too.

2. As mentioned earlier, I print occasionally. Mostly, I create slide shows but I do also create photo albums for the grandkids.

3. I was never able to enjoy photography when film was used. I had a camera and had some experience with it but it wasn't nearly enough to develop any sort of understanding of the field of photography.

And for #4, I believe I've answered this one in my earlier explanations.

I appreciate your views about Canon, cropped vs. FF and the links. I also like the idea of adding a hot shoe flash. Picking out lenses may be a challenge but I think it would be fun to have a choice about them. I want to be able to get close ups of birds, macro shots and then for photos inside the home for family activities.

And yes I am planning on keeping the Rebel. If I have two cameras, then I can have them set up for different situations! That'd be a plus!

So to wrap this long post up, I hope I've covered most of what was asked of me? Have I justified why I'd like new equipment?

I want to thank each of you and let you know I appreciate the time that you have taken to give a response to my general question. I know that this is an open topic and making suggestions for camera equipment is hard to do for others. I could ask any sales person and I'd probably get as many different reasons for a certain camera as there are sales people. I will welcome any other thoughts offered though! It is going to be a bit before I actually plop down any $$. Decisions are very hard for me to make. Always have been and probably always will be!

[george013]

........

A problem I have with my Rebel is that it doesn't seem to be sealed very well. It tends to draw moisture far quicker than I would expect a camera to do. I go through the stages of acclimating it to colder conditions by putting it on the side enclosed porch area and from there heading outside for winter shots. Before I realize it, I'm trying to get photos and instead of good results, there is a haze developing on my pics. It is frustrating. I'm hoping newer equipment will eliminate this problem.

.........

I don't understand this one. Doesn't make sense to me. Moisture only comes when the camera is colder as the environment.

If you want to go mirrorless pay special attention to the electronic viewfinder.

George

[Manfred M]

A problem I have with my Rebel is that it doesn't seem to be sealed very well. It tends to draw moisture far quicker than I would expect a camera to do. I go through the stages of acclimating it to colder conditions by putting it on the side enclosed porch area and from there heading outside for winter shots. Before I realize it, I'm trying to get photos and instead of good results, there is a haze developing on my pics. It is frustrating. I'm hoping newer equipment will eliminate this problem.

I can 100% guarantee that changing cameras will not have any impact on that issue. You are dealing with the laws of physics here and if your camera body / lens is colder than the dew point of the air, that will happen in any camera body and lens, regardless of whether it is "sealed" or not.

As a winter shooter, I go through that every time I shoot outdoors at this time of year and I do take care of how I handle the camera when I take it out from the relatively humid interior to the cold exterior and when I bring the camera back in. The same issue goes in reverse when visiting the tropics; going from a cold, air conditioned building or car and stepping outside without the proper precautions; instant fog up.

[Tringa]

If you really want an FF camera then go for it, but do consider carefully the points made above, re cost of the body, cost of the lenses, weight of both, FOV compared to a crop camera and, if I can add another, the possible need for a new computer to handle the larger files.

If you do go down that route there is a lot to choose from. In addition to Canon, Nikon and Sony have a look at the Pentax K1. I don't know what it retails for in the US but in the UK it is a lot of camera for the money. However, even it will probably eat up most of your budget.

Have you considered a newer and higher spec crop camera?

As you are already a Canon used then this would be a good place to start. The advantages of a newer/high spec crop camera are, I think largely two fold. Various camera functions are more likely to be accessed via a dedicated button/switch instead of in a multi-layer menu which makes using the camera easier, and the technology improves over time and while it would be wrong to say crop camera are now on a par with FF ones - many newer models run a very close second. If you do stick with a Canon crop camera check the lenses you have will fit and function in the same way as they do on your present camera. I do not know Canon so the Canon shooters here will be able to advise on this.

Dave

[DanK]

Sandy,

With all the information you provided and the additional answers since then, I think I can be more specific. This is a list of what I would do, but there are many choices, and it might not be the right answer for you. I'm treating $2500 as a fixed amount, so any additional $$ you spend on one piece of equipment is something else you have to forgo.

Before listing things, Manfred beat me to the keyboard: a more expensive camera will not be any less susceptible to condensation. It may be (depending on your selection) better sealed against moisture entering the camera, e.g., during rain.

1. You say you are keeping the Rebel. For me, that would end the discussion about brand. It makes no sense to own two cameras that can't share lenses and a flash.

2. Given what you wrote, I would stick with a crop sensor. You won't get enough advantages from FF to outweigh the disadvantages. (When I wrote about printing, I really meant "large". I print a good bit at 13 x 19, and I doubt you would be able to tell which are crop-camera photos.)

I'd start by comparing the features of the xxD series (70D, 77D) to the 7D II. They differ in build and controls, as well as price. I won't try to get into that.

With respect to Dave's question about lenses: all Canon EF-S and EF lenses work on Canon crop-sensor cameras, without exception. The limitation is solely that EF-S lenses won't work on FF. I should only crop for years, and one of my favorite lenses then (and now, for that matter) is the 70-200 f/4 IS, which is an EF (full frame) lens.

3. You mentioned that one of your interests is shots of your grandkids. Mine as well. For that, I consider a bounce-capable flash to be essential. I have used Canon 430 EXII flashes for years, but there are some good off brands as well. Ideally, spend $30 or so and add a bounce card, like a Demb flip-it. This is a discussion for another thread, but I would take the cost of a flash right off the top in deciding how much you can spend on other things.

4. Given your budget, I would buy refurbished gear. Canon won't refurbish gear unless they can bring it to near-new condition, and they guarantee all of it. I would have to check, but I believe they have extended the warranty from 90 days to 1 year, at least on some equipment. I am including lenses as well as bodies. My most used lens is an EF 24-105 f/4 that I bought as a refurb 3 or 4 years ago. It's been flawless. I would avoid used gear unless you know who is selling it or you get a warranty, as you would from some vendors (e.g., Adorama and I think B&H and KEH, the largest vendor of used gear). I generally opt for refurbs when I don't buy new, sometimes waiting for a Canon sale.

5. You need to think about lenses, which is a big reason not to buy a new body--to save money for other stuff. Your post suggests three ways to go, but you will probably need to pick one: a macro lens, a faster lens for indoor candids of kids, and a longer and better telephoto. The last is the most expensive. Re the second: If you are going to do candids with flash, a fixed aperture lens is really preferable, and you need something that stays no slower than f/4. I rarely use wider apertures for that purpose because at f/2.8, it's very hard to keep a moving grandkid properly in focus.

Dan

[skitterbug]

Hi Manfred and George - So you answered the question about moisture developing and apparently there's no way to stop it? Once the camera is the close to the same temps as the weather, I'd think it wouldn't be a problem. I wonder if the various composites cameras are made from could be more or less prone to this condition?

Fortunately, we haven't had tropical temps to deal with here! So it is only a winter time problem for me.

Thanks for the explanation!

[xpatUSA]

. . . Once the camera is the close to the same temps as the weather, I'd think it wouldn't be a problem.

"close to" is not good enough, sorry. It must be "equal to or greater than". And that also applies to the air inside the camera or lens, which is why it's best to wait a while, as has already been said. In fact the air inside the camera (and, more importantly, the lens) is where the condensation comes from - as soon as any inside surface drops below the dew-point temperature of the internal air.

I wonder if the various composites cameras are made from could be more or less prone to this condition?

Only in terms of time: for example, the temperature inside of a thin plastic body will equalize to surroundings quicker than a thick chrome-look plastic body. To do with heat conductance and surface emissivity.

[AlwaysOnAuto]

Hi Sandy,
I would take a whole different approach to your question(s).
I'd approach it from the standpoint of which camera will give you the most options in the future.
With a budget like you have, I'd look at getting a used Sony A7RII and some adapters for your lenses.
I'd then start looking for Nikon lenses that fill in the gaps of FL and Macro desires and get an adapter for them too.
Just another way of looking at the 'problem'.

By the way, my Sony gear is all used except for the one native lens (FE28 2.0) I have. My macro lenses were both bought off the Goodwill auction site and I consider them to be some of the best lenses I own. My Nikon D7000 was bought new but it hasn't been used for at least a couple of years now since I went to the Sony's.

[DanK]

"Close to" is not good enough, sorry. It must be "equal to or greater than".

Nope. The key isn't reaching the same temperature. It's warming the camera to a temperature that is greater than (not greater than or equal to) the dew point in the warmer environment. That's why during much of the year, one doesn't have this problem: the difference in temperature isn't sufficient to push the camera below the dew point in the warmer environment. Where I am, there is almost never a reason to think about this except during the winter, even though the outdoors is colder than the indoors for months in fall and spring. The exception, of course, is if the warmer environment is very humid, that is, if it has a high dew point. It's often a problem going into our nearby butterfly zoo, for example.

[Manfred M]

Hi Manfred and George - So you answered the question about moisture developing and apparently there's no way to stop it? Once the camera is the close to the same temps as the weather, I'd think it wouldn't be a problem. I wonder if the various composites cameras are made from could be more or less prone to this condition?

Fortunately, we haven't had tropical temps to deal with here! So it is only a winter time problem for me.

Thanks for the explanation!

Sandy - the effect is very much the same as when we put ice cubes in a drink and watch the condensation form on the glass. In the summer, the condensation will likely form more quickly than in the winter, as the air will be more humid in the summer. It doesn't matter if the drink is in a metal or plastic cup, or in a plain old glass, all will have condensation form on them. The metal cup will likely have this happen fastest, as metal is a good conductor and glass will be a bit slower than the metal. The plastic, which is the best insulator will take longer, but the condensation will still form.

This very much parallels what happens with your camera. If you take it from an environment that is cold into an environment that is humid, you will get condensation. If you take your camera from a humid environment and expose it to cold air, you will get fogging or even a bit of ice formation happening.

What you need to do is to let your camera warm up or cool down in a way that counteracts these problems. If you place your cold camera in a plastic bag or leave it in your camera bag before bringing it inside, then the air around it will have relatively little moisture and it will warm out without any condensation problems. If you are in a rush to see the shots you took, the plastic bag approach works, and moisture will form on the outside of the bag, without affecting your camera. Wipe the bag occasionally and when no moisture forms on the bag, you can safely remove your camera / lenses from the bag.

Your padded camera bag is an insulator and the dry outside air will be trapped inside it. It will take a lot longer for your camera to warm up, so leave it in the bag for 8 - 12 hours (I leave it overnight) and it should be fine in the morning.

Going outside, I have a slightly different trick. I generally drive to the shooting location and the outside air is fairly dry. When a car warms up, I will open my camera bag and will remove my lens caps to let the dry air at the gear. When I get to my shooting location, there will be little moisture to condense when it hits the cold air. I might also remove my filters from in front of the front element of the camera lens, as I have run into a situation where I installed the filter in humid conditions and the moist air trapped between the filter and lens will condense / freeze.

[skitterbug]

If you really want an FF camera then go for it, but do consider carefully the points made above, re cost of the body, cost of the lenses, weight of both, FOV compared to a crop camera and, if I can add another, the possible need for a new computer to handle the larger files.

I've pretty much decided on the crop factor camera. New computer - no. This one is a fairly new iMac and can handle pretty much what I "throw" at it.

As you are already a Canon used then this would be a good place to start. The advantages of a newer/high spec crop camera are, I think largely two fold. Various camera functions are more likely to be accessed via a dedicated button/switch instead of in a multi-layer menu which makes using the camera easier, and the technology improves over time and while it would be wrong to say crop camera are now on a par with FF ones - many newer models run a very close second. If you do stick with a Canon crop camera check the lenses you have will fit and function in the same way as they do on your present camera. I do not know Canon so the Canon shooters here will be able to advise on this.

If I was leaning toward switching brands, now would be the time to do it since the cost involved in the Rebel isn't huge. I do like the idea of being able to use the kit lenses from the Rebel on the new crop camera so I'll probably stay with Canon.

Thanks for the info and opinions! I appreciate this "thinking time" about all options! It is helpful.

[billtils]

Sandy

I'm a bit late to this thread but having gone through the same exercise with Nikons, here are a few observations:

1: I don't see any compelling reason to shift from Canon
2: I don't see any compelling reason to shift from your "fairly new" iMac
3: Crop or FF depends on what you do. I don't have any single preferred genre but probably do more nature, especially birds, than anything else. I have a couple of keen and very capable friends who are "birders" and Canon users, and each has a 5D3 and one of the higher end crop bodies. Both advised me that they get better images cropping from the FF than they would get from the crop sensor bodies - that made me go for the FF and I'd unreservedly agree with them.
4: Weight - it all depends. My FF D750 body is lighter than the D7100 crop it replaced. Most decent glass for the FF will indeed be heavier on the pocket and on the arms but this too is not a universal truth - my "nifty fifty" is light, low cost, and sharp as you would ever wish..

[Tronhard]

Hi Sandy:

I don't see anywhere that you have said exactly what gear you have, apart from the fact that you have a Rebel and kit lenses, and I would be interested to know. When I chose Canon I did so because of the glass - they have (as I understand it) the largest range of lenses available from one manufacturer. However one other point that you made also was of interest: that you are taking photos of grand children. From that I assume that your are in your "mature years" and one of the issues of ageing (as I have discovered) is that we find it difficult to carry heavy gear around with us for long periods - loss of muscle mass and injuries take their toll. I don't know if that applies to you. I have found myself shooting with the Canon EOS M5 and the EF-M series lenses quite a lot lately. Yep, they can be considered a bit on the slow side, but the images are good from the units I have and they take any flash as required - the M5 has a built-in flash. Not only did I save weight, but volume as well. Not only is the M series less "in your face", but I can fit two M bodies, along with 4 lenses in the same space I would carry one body and two lenses in the DSLR range. I would suggest having a look at the EOS M-5, along with the 18-150mm lens, which is a good general purpose lens. If you REALLY want to use your kit lenses you can get a 3rd party lens adapter and use ANY Canon lens with the M-series bodies.

[DanK]

Both advised me that they get better images cropping from the FF than they would get from the crop sensor bodies - that made me go for the FF and I'd unreservedly agree with them.

That's interesting. I would be interested in seeing comparisons. You certainly lose pixels by cropping like that:

7DII, entire frame: 19.96 MP
7D I, entire frame: 17.92 MP
5DIII cropped to APS-C sensor dimensions: 8.64 MP.

This loss of detail won't generally be apparent online unless one crops severely because of the low resolution of computer monitors. Printing is another matter. And there may be other attributes of the particular FF in question that offset this consideration anyway, e.g., in my case (7DI and 5DIII), low-light characteristics.

I don't do many birds, but I almost always use the crop because I know I will often have to crop substantially in postprocessing, even with my longest (400mm) lens.

BTW, when I got my 100-400, I did an A/B comparison to see the effect of increasing the reach of the 5DIII by using a Canon 1.4X II teleconverter. Condition 1 was 5DIII, the lens at 400mm, and the teleconverter. Condition 2 was the 7D with the 100-400 set at 350 mm, which is the same angle of view. No contest: the second was much sharper. I assume the main issue was the 1.4 x teleconverter, not the focal length setting of the lens.

But in any case, this isn't much data, so if you have a few image pairs that illustrate your point, I'd be eager to see them. It might change what I do, since I have both options.