Longer Lens or Crop Sensor

If you need to reach out,
  • My first option would be for a longer lens
  • But at a certain point, you will not be able to afford the $$,$$$ for a LONG lens. So there is a practical/affordable limit to how long a lens you can get.
  • Manual Focus (MF) alternative: Because the $1,400 cost of a 500mm AF lens (Nikon 200-500mm) was way beyond my limit, I went with a used MF Nikon 500mm mirror lens. The used MF 500mm lens was 10% of the cost of the Nikon 200-500m zoom lens. I was not going to pay $1,400 for a lens that I would use only very occasionally, like less than 1/2% of the time. I would rather put that $ into a 70-200 f/4, which I would use much more. Your priorities may be different than mine.
    • Con: I cannot follow focus on FAST moving subjects. My hit rate shooting tennis was less than 20%. So MF is fine for stationary or slow moving subjects, but not for fast moving subjects.
    • BTW, I have a MF 800mm mirror lens, for when the 500mm lens is not long enough.
  • If you want a LONG lens, there are options to put a dslr onto small astronomical reflector telescopes.
    • You can get some seriously LONG glass here.
    • Con are: Manual focus. The telescope and mounts are BULKY and not simple to transport or setup. The mounts are NOT made to track FAST moving subjects, like flying birds or surfers or similar. Some of these astronomical teles are somewhat fragile, compared to a SLR lens. Like a mirror lens, the aperture is fixed, so you expose by ISO level and shutter speed.
  • My second option would be a crop factor body, in place of the FF body.
  • Or a FF body with a crop function.
  • In my case, since I currently use a DX crop body, #2 is NA, as I am already here.
  • Use a tele-converter.
  • The problem is you need a GOOD tele-converter $$$ to maintain image quality. Not a cheap $30 one, which will degrade the image quality.
  • There are some lens/tele-converter matched pairs, and if so that pair is what you should get. Don't substitute.
  • Tele-converters will cost you f-stops. Once you go beyond f/5.6 or 8, some AF do not work, it is too dark to function and it may be too dark to manually focus.
 
A great summary @ac12
One additional thing to remember with teleconverters is even the best ones magnify any flaws in the main lens. For good results you need expensive lenses in front of them :apologetic:

I've arranged my astro scope to mount on a heavy weight normal tripod (Manfrotto 058 with a fluid head). In tests diffraction had a significant effect with the higher magnification options, but prime focus worked pretty well on MFT. Still a complicated & heavy set up but usable where you have plenty of time to set up.

MF shots of moving subjects are possible usually the result of focusing ahead & then waiting for the subject to come into focus. Though when the objects are far enough away this isn't needed - I had no real problems shooting power boat racing through a 1000mm telescope.

I've also gone the mirror lens route. My 600mm f8 isn't practical to handhold on MFT (1200mm equiv FOV) but with a focal reducer coupled up (900mm FOV and an extra stop of light) handholding is possible when braced.:aiwebs_016:
The same lens is usable on APSC too. :1247:
 
@pertrochemist,
I've handheld the 500 mirror on my D7200, and it worked OK.
And you are correct, if you can brace yourself, you can hand hold it.

But for me, hand holding is not practical for any length of time, like shooting an event. As I get tired, I get less steady.
For tennis, I put the rig onto a gimbal mount on my tripod. That gimbal makes it sooo much easier to track a moving subject than with the 3-way head. And it takes care of the weight and stability issue. But a gimbal on a medium/heavy tripod is heavy and bulky to transport. Mine has to go into a cart to move, I'm too old to carry all that gear.
 
I think that crop sensor is clear winner: longer lenses are more expensive than standard telephotos, crop sensors are cheaper than full frames so save your $$$,. And, don't forget that more element and glass will mean less sharpness.
 
I've had the Nikon 500mm Reflex MF lens and also a Celestron 1,000mm focus ring reflex lens. As mentioned you can hand hold it if you practice a lot. FYI, I use telescopes a lot. My main scope is 3,054mm and I have smaller ones.

But with AF there are lower cost alternatives. I sold my Nikon 500mm Reflex MF and went to a Sigma 150-500mm lens. It's a pretty good lens for the price point. Now you can get them for under $500, even down to $270 just checking eBay. I then upgraded to the Tamron 150-600 lens and have that now.

For you, since you want a better option for Wildlife I think a MF lens makes it very difficult as the subject can be totally unpredictable. I've shot aircraft at 9+ miles away on my telescopes but it's easy to determine it's flight path for focusing. But wildlife .. which way and when will it move and how fast; it's too unpredictable ?? I think going with a longer AF lens will definitely help initially. The one example Sigma 150-500 is going to help a lot on your FF camera. Then later on you can add a Crop body to it.
 
Very informative (and spirited) dialogue. Clearly fast glass is the best and much more expensive solution.

Having a good second body is a plus though.

I am told Sony APS-C sensors are very good at high ISO and that there is an adapter that would enable it to work with L series Canon glass. Anyone have experience or thoughts on this?

To the best of my knowledge sony are contracted to make the sensors for every camera manufacture except canon.
 
The crop "reach" advantage is a myth because the effect is only the same as you would get by cutting off part of a full frame sensor, i.e. recording a smaller portion of the scene captured by the lens.

The advantage is a myth?! the advantage is real.

what complete disingenuous drivel.

Wow. Okay, let's try to clear some of the water you've clouded, shall we?

Asserting with such condescending language does not make anything so. On the contrary, your own remarks here ably demonstrate the properties of which you falsely accuse mine. Your obnoxious expression would be excessive even if I had been incorrect. In light of the fact that you are actually in error, about the topic and my post, it's inexcusable.

I'm sorry, but cropping a 24MP FF image to fill the frame with a bird and ending up with a 10MP image is not the same as an uncropped 24MP aps-c image that required no cropping to fill the frame with a bird.

That is not what I said, and resorting to such juvenile tactics only reveals your desperation to cling to a delusion. I did point out that a crop sensor would produce a larger image if it possessed a higher pixel count, but that is not the point of contention here and you know it. The claim was that the reduced field of view of a smaller sensor is an equivalent gain to increased magnification, which it is not. If a full-frame and crop sensor of equal pixel density, are used to shoot the same scene, centred on the same point, at the same focal-plane distance, through the same lens, at the same focal length and focussed distance, the crop sensor will merely record a smaller portion of that captured by the full-frame. A higher resolution sensor of any format will produce a larger image, but this is not an inherent property of sensor size.

How about we go about this a different way:

You have two cameras; one crop and one ff. Both with the same lens.

there's a bird on a post in front of you, you look through each viewfinder and decide to shoot with the crop sensor because the bird fills the frame -- even though we are using the same lens.

what do you call this effect?

we know it's not reach, cause reach is a myth. so what should ever photographer in the world start calling it?

In your example, the bird fills the frame because the frame is smaller, not because the image is enlarged. What should we start calling it? How about "reduced field of view"? I think people do generally mean "magnification" when they refer to "reach" in the context of photography, although the term still seems in quite casual use and perhaps yet to be settled. If your definition were to become the accepted one it would be of no value, and likely to mislead novices. This is why the term "crop sensor" was adopted, not "telesensor" or something of that sort, because the frame-filling effect of a smaller sensor is only due to reduced field of view. Why would you promote this as an imaging advantage, except to contort the meaning to conform to your own misapprehension? You are simply adopting the self-serving semantic ploy of Carroll's Humpty Dumpty.
 
That is not what I said, and resorting to such juvenile tactics only reveals your desperation to cling to a delusion.

directly debating a topic is not juvenile.

you said and I QUOTE: "The crop "reach" advantage is a myth because the effect is only the same as you would get by cutting off part of a full frame sensor, i.e. recording a smaller portion of the scene captured by the lens."

I gave a clear example disproving how it's not the same:

"Cropping a 24MP FF image to fill the frame with a bird and ending up with a ~10MP image is not the same as an uncropped 24MP aps-c image that required no cropping to fill the frame with a bird."

in that sentence you even admit there's some sort of real phenomenon happening, but the crop sensor is NOT cropping the image, it's capturing the image at 100%. So again, it's different.

you cannot deny that the same lens on a smaller sensor results in a narrow FOV. that's a 100% real reach advantage.

If you want to create the same image on a FF as a APS-C sized sensor, uncropped, 100% native resolution, you need a longer lens because a 200mm lens on a FF body, just doesn't quite have the reach as a 200mm lens on a APS-C sensor.



In your example, the bird fills the frame because the frame is smaller, not because the image is enlarged.
so? this is irrelevant. it's not about the how.

but youre admitting there's a difference.

This is why the term "crop sensor" was adopted, not "telesensor" or something of that sort, because the frame-filling effect of a smaller sensor is only due to reduced field of view.

so? again, this is irrelevant. I know how a crop sensor works, this is not the argument.

and a 4/3 sensor is called micro 4/3 because it's "micro" and 4:3 what's your point? does it not crop the image?

Why would you promote this as an imaging advantage, except to contort the meaning to conform to your own misapprehension?

1. it is an advantage.
2. I have no mistaken belief. you're fooling yourself.

When someone says "youll get more height with these shoes" in terms of basketball

Are they taking about the ability to jump, or physically being taller in them. I'm going with the former.
 
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........... If a full-frame and crop sensor of equal pixel density, ..............

Isn't the pixel density of a Crop much higher than a FF which makes your assertion here sort of prove your argument wrong? Or are you attempting to base your argument on the fact an individual is asking to compare a 20MP FF vs a 12MP crop for example numbers? Because most people would tend to think you would be comparing 20MP FF to 20MP Crops (example) when asking about which has better reach.

The idea of better reach for me is how far away can I get from subject and maintain a "minimum" quality (in terms of pixels captured and this would depend on usage planned on final print of course) of that desired subject (bird covering whole frame for instance) I'm not going to discuss better low light and such unless that is also a part of the question. If someone asks which is better for "Reach", a FF or crop, I'm not going to be comparing a FF or crops from 20 years ago to the other models of today. I'm not going to compare the top of the line FF vs the cheapest entry level crop. If they both start off at 20MP and you have to throw out a bunch of that data in your FF to get the same image (Bird filling frame) than the answer is pretty obvious.
 
My Nuclear button is bigger than yours, and it works.
 
I can tell you that in happy wth what i can do with my 80d and 150-600 g2 tamron...
 
I can tell you that in happy wth what i can do with my 80d and 150-600 g2 tamron...

Good to know. I have heard good things about the 80D - in fact only good reports. I think I am going to wait for the replacement for the 7D mark ii (rumor has it the mark iii will be out this spring/summer) and then have a look at the Tamron 150-600 g2 as the next step after that. Your combo sounds like a great way to go.
 
Good to know. I have heard good things about the 80D - in fact only good reports. I think I am going to wait for the replacement for the 7D mark ii (rumor has it the mark iii will be out this spring/summer)...
Good, cuz I have my eye on the 7D Mk II :)

... and then have a look at the Tamron 150-600 g2 as the next step after that. Your combo sounds like a great way to go.
Y'know what I'd really like to put on a 7D Mk. <whatever>? A Canon EF 400mm f/4 DO IS II USM. But at $7,000 new, that's not very likely gonna happen :(
 
Photoflyer: Can your FF shoot in crop mode using the FF lenses? If so, try that initially, and see if it gets you the results you are looking for. It seems to me that a menu selection is a whole lot faster and cheaper than picking the wrong path.

Both of these are with a 28-85 at 50mm. The first is FX mode, the second is DX mode; all other settings are the same. Please excuse the soft focus, I shot them through a screen door.

 
Can your FF shoot in crop mode using the FF lenses? If so, try that initially, and see if it gets you the results you are looking for. It seems to me that a menu selection is a whole lot faster and cheaper than picking the wrong path.

Interesting question. I do not believe so (it is a 6D Mark II). Maybe someone else knows. I have studied the manual ad not seen that option.

The other reason to get a crop sensor is to have a second body in addition to the extra "reach" it provides and the reason to wait for the 7D mark iii is to get the latest technology though the 80D and the 7D mark ii look compelling. I'm not in a hurry...yet.
 

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