# Why bird photographers use "big" glass...



## rip18 (Dec 8, 2007)

At the request of DRB1313 & FeralOne, I took my “big” lenses out to shoot a canned Coca-cola at full frame & then measure the distance from the Coke can to the camera sensor (roughly middle of camera body).  This would approximate trying to shoot a bird and fill the frame with it.  

Just for reference a Coke can is 5” tall and 2.5” in diameter.  A Carolina chickadee (when dead & stretched out) measures 4.75” from bill tip to tail tip (this would be about 2.5” tall when alive & standing up).  A northern cardinal is 8.75” from bill tip to tail tip when dead (or about 5” standing up).

Serious bird photographers buy as much glass as they can afford, & this exercise showed me why.  I knew we would all learn something from it, but I admit to being really surprised at the distances it took to fill the frame with the Coke can – they were AMAZINGLY short!

I made shots with a Nikon D70 and the 600 mm w/2x teleconverter, the 600 mm, the 400 mm, and a 300 mm.  The shots were all so close that I had to use an extension tube on the first 3 and the macro switch on the last one.  (An extension tube is a tube with camera fittings that is hollow – no glass; this allows the camera to focus closer to an object than the lens would otherwise be capable.).


----------



## rip18 (Dec 8, 2007)

The Nikkor 600 mm with a Sigma 2x teleconverter & a Nikkor 27.5mm extension tube will the first shot.  Because I had the extension tube between the lens & teleconverter, this is effectively an 1882.5 mm when compared to 35mm or just over a 37x pair of binoculars.  Note that I had to either: A) use the extension tube or B) back up a bit further because I was within the minimum focusing distance of the lens…  The distance it took to get a full frame shot was 30.6 feet.

Oops. I felt the slow shutter speed when I took the documentary photo, but thought I was okay - and I only took one, so we've got a slightly blurry documentary photo of the set up...  My bad...


----------



## rip18 (Dec 8, 2007)

Then, I took the teleconverter & extension tube out & moved up for a full frame shot with just the 600 mm.  I had to put the extension tube back in because once again I was within the minimum focusing distance.  This is a 941.25 mm equivalent for 35 mm or 18.8x pair of binoculars.  The distance it took for a full frame shot was 15.8 feet (which is just more than half of the one with the 2x teleconverter).


----------



## rip18 (Dec 8, 2007)

Then I took the 400 mm for the same shot.  Once again, I had to use the extension tube.  The 35 mm equivalent is 641.25 or 12.8x for binoculars.  The distance for a full frame shot was 10.8 feet.


----------



## rip18 (Dec 8, 2007)

Then I took out my Sigma 70 to 300 mm & tried a shot at 300 mm.  I was too close to focus, but rather than put in the extension tube, I went & got Mrs. Rip’s 70 to 300 which has a “macro” switch.  At 300 mm this is equivalent to a  450 mm 35 mm lens or a 9x pair of binoculars.  The distance for a full frame shot here was 7.3 feet.


----------



## rip18 (Dec 8, 2007)

And for grins & giggles, I also took a picture of my beanbag.  It takes 16 pounds of beans to fill the bag, the 600 mm on the bag weighs about 13 pounds, & the camera weighs about a pound & a half, so this whole conglomeration weighs right at 30 pounds….

But back to the task at hand, here is a quick summary of the distance to get a full frame Coke can shot with different lens combinations using a Nikon D70 (Note that for a full frame sensor like the D3, the distances would have been even closer!):

600 mm w/2x teleconverter & long extension tube took 30.6 feet
600 mm w/long extension tube took 15.8 feet
400 mm w/long extension tube took 10.8 feet
300 mm took 7.3 feet

One noted bird photographer says that he ALWAYS uses as many stacked extension tubes between his teleconverter & lens as he can in a feeder situation because it does effectively (but to a small degree) increase the magnification of his set up.

Well, that certainly was an interesting test.  Thanks for suggesting it.  It certainly makes me appreciate all the "little" bird pix that folks post.

I've got a buddy that is a good hunter, woodsman, & naturalist.  He has observed several times that you can find out who is a really good hunter or not (no matter how many deer they have killed how) by giving them a camera with a 300 mm lens on it & telling them to go get a full-frame image of a male cardinal (& not at a feeder, but in the "wild").  That is a TOUGH assignment!

Oops...another blurry hand-held documentary shot...


----------



## jason308 (Dec 8, 2007)

Thanks for the lesson, Rip....Looks like the coke can was a pretty representative subject....


----------



## Smokey (Dec 8, 2007)

Wow!! What a great lesson that was for me....I think.... 
Now lets see the _"It's so easy that even Smokey can understand it"_ version.


----------



## rip18 (Dec 8, 2007)

All right - the "Why Bird Photographers Use 'Big' Glass - the Condensed Version" -

With an ultra-tele (600 mm w/extension tube & 2x teleconverter) you have to be about 5 yards from a small bird to get it at full frame.

With shorter lenses you have to be even closer...


----------



## FERAL ONE (Dec 8, 2007)

smokey, the lesson i got was if i want to get a full frame shot of a bird, IT BETTER BE DEAD!!!!!      just kiddin'.   thanks rip for this lesson!!! it was eye opening to say the least!!!!


----------



## Smokey (Dec 8, 2007)

rip18 said:


> All right - the "Why Bird Photographers Use 'Big' Glass - the Condensed Version" -
> 
> With an ultra-tele (600 mm w/extension tube & 2x teleconverter) you have to be about 5 yards from a small bird to get it at full frame.
> 
> With shorter lenses you have to be even closer...



Okay, but I thought the "big glass" was used to pull stuff thats way out yonder in to right here at ya.


----------



## jason308 (Dec 8, 2007)

Smokey said:


> Okay, but I thought the "big glass" was used to pull stuff thats way out yonder in to right here at ya.



Correct.....The 600mm w/2x converter would reach waaaayyyyyy out there if you were shooting a deer, bear, or other larger subject....Just depends on how big your subject is....I don't even have a guess how far away you could get a full frame shot of a deer with that setup....Maybe Rip can give us an idea...


----------



## ronfritz (Dec 8, 2007)

It has been 35 years since I've been around people asking questions like that...and never before on a Saturday night.

Mr. Rip is on QDM land with his 300 mm lens and is 7.3 feet from a 5.5 inch Coca Cola can.  Mr. Rip is framing the Coca Cola can so that the picture will contain .25 inches on top and bottom.  Suddenly a fine buck begins walking towards him.  Mr. Rip would like to take a picture of the buck when it fills the frame.  The tallest point on the buck is 5'.  How far will the buck be from Mr. Rip when the buck fills the frame of Mr. Rip's camera?

Assuming the camera is pointed at the center of the can, that means there is a right triangle.  The bottom part of the triangle is 7.3' and the verticle part is half the length of the can plus the 1/4" margin.  Therefore the vertical is 3".  Half the height of the deer is 30".  I think you could just assume that the deer is ten times taller than the Coke can so you can be ten times farther from the deer and still fill the frame.

...or you could calculate (I think) using the formula: Tangent = vertical/horizontal.  I think that comes out the same but maybe there is a 15 year old reading who is taking Geometry or Trig who could validate.

If I'm right, then what could be said is that *roughly* ... anything 5 feet tall would fill the frame when it was ten times farther than the numbers Rip provided above.

600 mm w/2x teleconverter & long extension tube took 306 feet
600 mm w/long extension tube took 158 feet
400 mm w/long extension tube took 108 feet
300 mm took 73 feet

My feelings won't be hurt at all if I'm wrong or off, but I do think its possible to use Rip's numbers to extrapolate the min distance to fill the frame with a deer.


----------



## jason308 (Dec 8, 2007)

ronfritz said:


> It has been 35 years since I've been around people asking questions like that...and never before on a Saturday night.
> 
> Mr. Rip is on QDM land with his 300 mm lens and is 7.3 feet from a 5.5 inch Coca Cola can.  Mr. Rip is framing the Coca Cola can so that the picture will contain .25 inches on top and bottom.  Suddenly a fine buck begins walking towards him.  Mr. Rip would like to take a picture of the buck when it fills the frame.  The tallest point on the buck is 5'.  How far will the buck be from Mr. Rip when the buck fills the frame of Mr. Rip's camera?
> 
> ...



Yeah, what he said....   I was looking for an experience based answer-but that one will work fine too!!!  Thanks Ron....

I had a calculus teacher (maybe it was pre-cal) who asked a similar question in class regarding a tree she wanted to fell-but didn't know if it would hit her house at that distance.......She gave us some numbers (don't remember what they were, but they were sufficient if you knew what you were doing).......So she asked whether or not the tree would hit her house.....I raised my hand, and when she called on me I asked her why couldn't she just notch the tree on the back side and fell it away from the house????

Point is, I guess i will call Ron with a math question from here on out....I have some CAPM problems you can work on (and teach me ..) too if you like.....


----------



## DRB1313 (Dec 8, 2007)

Rip, You have gone above and beyond on this experiment and I can't say enough how thankful I am that you took the time to do this.
I am now very clear on what type of range is involved in getting a full frame shot of a small bird.
What I am most intriqued with, is that it took a distance shorter than the minimum focusing distance of the lens to achieve this.
I will conduct my own test tomorrow with my 70-200mm, which has a minimum focusing distance of 4'9" and see what happens.
I will also throw on the 1.4ext and see how this will effect the shot.

Ah Heck! Maybe I'll just go do it now.

Once again Thank you very much for your time and effort.

I'll be back in a minute.


----------



## ronfritz (Dec 8, 2007)

Jason - Don't forget my disclaimers.  My money's on the answer provided by the first 15 year old that reads this post. 

Now the other aspect of this that is interesting is depth of field and sharpness.  You can see the ever so slight softness imparted by the teleconverter.  In the straight 600mm shot, you can see dof is so narrow that the bottom part of the can is not quite in focus.  The shorter lens - the 400 is going to yield a tad more dof.  To me, that suggests that, in low light, the 400 might be the better choice in some light situations because you could shoot it wide open without loosing the dof needed to get the whole bird in focus.


----------



## Gunsmoke (Dec 8, 2007)

like crocidile dundee said "now this is  a lens" serious  set up you have there rip


----------



## jason308 (Dec 8, 2007)

ronfritz said:


> Jason - Don't forget my disclaimers.  My money's on the answer provided by the first 15 year old that reads this post.
> 
> Now the other aspect of this that is interesting is depth of field and sharpness.  You can see the ever so slight softness imparted by the teleconverter.  In the straight 600mm shot, you can see dof is so narrow that the bottom part of the can is not quite in focus.  The shorter lens - the 400 is going to yield a tad more dof.  To me, that suggests that, in low light, the 400 might be the better choice in some light situations because you could shoot it wide open without loosing the dof needed to get the whole bird in focus.



Reckon the extender played into that any????  I reckon it wouldn't matter if you were after the full frame coke can shot...But maybe a touch less distance and no extender with a little crop??? (I realize that this was done to show full frame shots)...


----------



## ronfritz (Dec 8, 2007)

Rip can render the official opinion but I have to assume any TC is going to soften the picture just a little bit.  What is amazing to me is how little softening there is on Rip's 600 + 2x TC shot.

The thing that occurred to me though is that its not just filling the frame... its filling the frame with a subject that has good focus.  And I'm thinking that in low light situations, that might mean using the 400mm and getting closer instead.  Again I'll leave the final answer to Rip but it looks to me like you have to pay attention or you may fill the frame with a bird who's beak is in focus but body is not.


----------



## DRB1313 (Dec 8, 2007)

Ok, I'm back and it looks like Ya'll have solved the World's problems,Well At least mathematically.

PLEASE! Don't pay any attention to image quality or any softness issues in the following photos.
I KNOW THERE WAS CAMERA SHAKE.

Very interesting find though.
The minimum focusing distance required for my 70-200 is 4ft. 9inches.

To get the can to full frame I had to get the sensor to 4ft. 1 1/2", but could not aquire focus.

The first image will illustrate the size of the can in the image at the minimum 4'9" distance. Focus aquired.

The second shot reveals the interesting part. I added the 1.4ext and the minimum focusing distance DID NOT CHANGE, I was able to aquire focus at 4'9" and filled the frame.

Very interesting.


----------



## FERAL ONE (Dec 8, 2007)

great examples yall!!! now let me get this straight, i have to buy rip AND drb a coke ????


----------



## rip18 (Dec 9, 2007)

I saw the softness in the first shot as well.  I'm not sure if it was as much the extender as it was my poor focusing?  At longer distances, there is a bit more depth of field with those same settings, but up close, I had better be dead on...  I see everybody talk about the teleconverters reducing sharpness, but in real life, I don't see so much the teleconverter reducing sharpness as much as people using sloppy technique - when you suddenly go from 600 mm to 1200 mm, you better be using your best technique...  Just a tad of camera shake/movement/etc. and it will show up.

Kind of like the guy saying that he can't hold his gun steady at 10x, but when his scope is on 3x he is fine.  The gun is still waving just as much, but you can't see it.  When you zoom in to 1200 mm - you record the waving...

All that to say, at f/4 I had a very shallow depth of field at 30.6 feet, and it is likely that I missed the focal plane...


I think Ron's distance calculations are going to be pretty close based on what I have seen in the field.  Since the camera works with prisms, I think the actual calculations would involve trig rather than geometry, but those assumptions & geometric calculations look pretty close.  Actual distances probably a bit shorter?

For the sake of this experiment, we have been looking at getting the Coke can at full frame.  In most cases, small birds look better with just a bit of "supporting" habitat around them, so the actual distances for small birds are often just a smidgen more...

Low light pix of small critters with big lens are a real pain!  You can't use a slow shutter speed because the buggers move (ALL THE TIME!).  The best you can do is focus on the eye & hope you freeze the movement & get a deep enough shot to be useful (or use a flash with Fresnel flash extender - like the Better Beamer - and then you get both faster shutter speeds & the ability to use smaller aperatures for more depth of field).

Great addition, DRB1313, I almost pulled out the 80-200, but didn't.

Shoot, FeralOne, that Coke is on me.  I thought about sending you a bill, but that is the first canned Coke I have had in ages, and I really liked it!


----------



## leo (Dec 9, 2007)

*WOW rip*

very educational demo

Thanks for doing it for us

Kinda confirms what I thought .... you got to get real close to get shots that you don't need to crop


----------



## jason308 (Dec 9, 2007)

ronfritz said:


> Rip can render the official opinion but I have to assume any TC is going to soften the picture just a little bit.  What is amazing to me is how little softening there is on Rip's 600 + 2x TC shot.
> 
> The thing that occurred to me though is that its not just filling the frame... its filling the frame with a subject that has good focus.  And I'm thinking that in low light situations, that might mean using the 400mm and getting closer instead.  Again I'll leave the final answer to Rip but it looks to me like you have to pay attention or you may fill the frame with a bird who's beak is in focus but body is not.



I agree about the 400mm in low light....And I am a BIG fan of cropping (if for nothing else by necessity...) And all of his shots (600mm +2x tc) he has posted are amazing to me....You hear folks everywhere say oh you can't use a 2x tc and get any kind of results.....Heck this a manual focus only set up too and he nails em every time!!!!  I imagine my best effort with that rig would be just a colored blob in the frame.....

Thanks again Rip for posting this comparison.....I know that took a little time to set up, take down and process too....


----------



## Hoss (Dec 9, 2007)

Great tutorial.  It does confirm what I've seen with Bigma, you may have a lot of lens, but you still gotta get real close for a full frame shot.  That would be why most of mine are crops.  
Thanks for sharing the info.

Hoss


----------



## ronfritz (Dec 9, 2007)

I did my own version of the RipTest….not sure if its going to add much to what’s already been done but figured I might as well add it to the thread as long as I went through the exercise.... at least you get to see another rig in action.

I wanted to take some shots that would validate what I said up above about using size and distance measurements from a single shot to draw conclusions about what would fill the frame at other distances….the same height/distance ratio can be applied to any other subject to get the distance.  In fact, I have an old Sigma lens from back before autofocus that worked on the same principal.  It is marked with a subject dimension scale that is intended to allow you to pre-focus for a particular sized subject.  You set the focus ring to 10 meters and when a 10 meter object fills the frame, its in focus.

Anyway.  I attached both the 1.4 and 2.0 teleconverters to the Sigma 120-300, attached the cable release to the camera, set the camera in mirror lockup mode, mounted it to the tripod and then hung the lens case (with the 150mm Sigma in it) on the lens to dampen vibration.  Not sure if that’s good practice or not.  Rip, please tell me if hanging something on the lens like I did is a good or bad idea.

The first shot was from 21' and the image covered 7.5" vertically.  The second shot was from 120' and the image covered 44" vertically.  The ratio of subject height to subject distance is .357 and .367.  I'm thinking if I could measure a little more accurately the ratios would be equal.  So with this setup, at 100 yards, a 9' tall object would fill the frame.  Since specs for most big lenses provide the picture angle, a person ought to be able to calculate the area covered by the view finder.  Or, you could just take a picture of a ruler from a known distance and calculate the ratio.

To me, this telephoto lens stuff is an interesting topic and one that may be helpful to many folks, especially those who are on the verge of acquiring a nice camera.  I know, back in 1978 when I bought my first SLR - an Olympus OM-10 - I almost immediately bought a Tamron 70-200 zoom because I had to have a telephoto lens.  The prospect of bring stuff closer was so intriguing I could not hand them my money fast enough.  In hindsight, I can only think of one good picture I took with that lens; it wasn’t sharp, it was slow, and it definitely didn’t have no VR….and it really didn’t “bring stuff closer” like I had envisioned.  The reality is, if your camera zooms to 400mm, you’re probably gonna need to be within 50 yards of the deer to fill a good piece of the frame.  I’d say the 400mm is probably about the photo equivalent of the Marlin levergun in .357.  It’s definitely not a .308 or .30-06.


----------



## FERAL ONE (Dec 9, 2007)

ron, i did the same, jumped on a 75-300 mm with the hopes of being able to read the fine print on a ceral box at 1.5 miles!!! then i added a 2x tc!!! i found out real quick that the more zoom you have, the more tripod you need!!! i got some decent shots with the zoom , but none of mine are good with the tc. unfortunately i jumped on the first cheap thing i could find . i am learning lessons, some of them more expensive than others!!!


----------



## Hoss (Dec 9, 2007)

Thanks for the additional insights Ron.  Confirms what I expected from this post.

http://forum.gon.com/showpost.php?p=1400767&postcount=24

Hoss


----------



## rip18 (Dec 9, 2007)

More great examples.  

rf- I think hanging the bag on your setup would help dampen any vibrations/movement.  I would NOT do that if there weren't a mounting foot on the lens (i.e., if the camera BODY were attached to the tripod).


----------



## woodies art (Jan 30, 2008)

Wow I didn't expect this kind of response this tread will have to be bookmarked the information that I just read is priceless and saves a person who knows the amount of research They say a picture is wroth a 1000 words but these 1000 words posted here are wroth 1000's of setup Thank You one and all for the most valid information and the time that you put into my request once again many many Thanks.


----------



## FERAL ONE (Jan 30, 2008)

woodie, a lot of tips are in a sticky at the top of the page. folks have been real good about teachin' us beginners !!!


----------



## JasonF (Jan 30, 2008)

What a great thread!!  Hey Rip, that is a sweet set-up you have there with the camo on your lens and camera.


----------

