How to get the maximum from your telephoto lens

Some good info I got from a member on Nikonians and thought I'd share it with you. Especially informative for anybody getting a super telephoto lens.
I got the new 150-500mm and was a bit discouraged, but feel a bit better now. I have been shooting between 100-300 yrds and have to do heavy cropping which gave me a soft image. But when no cropping is necessary it looks pretty good.
Now I got this response from Dave "Telecorder"
Andre--
Good for you! You're learning the limitations with your understanding.

Many people move up to a long lens with unrealistic expectations; They soon find (or not) that user technique and subject distance are two critical issues that work against them if they're not fully understood. Add in OS/VR and the circumstances/expectations are compounded.

In most all cases at the long end of a lens' reach, new users moving up belatedly find that their technique needs dramatic improvement that will only come with extensive use/experience. I firmly believe a lot of new user reporting issues with, and 'blaming' a new long lens as being poor, have more to do with their techniques than the glass.

Likewise, subject distance seems to be dramatically misunderstood. Its been my experience that an image needing to have more than ~30-40% of the original field of view cropped to compose an image is where the image quality begins to suffer. There are just not enough remaining pixels covering the subject for the desired detail.

Take a 2-3' tall Bald Eagle. The vertical FOV of a 3008w x 2000h image at 200' is only ~6' or 72" for my Bigma at 500-mm. To fill the vertical FOV, one would need to crop out 1/2 - 2/3 of the FOV.

Thus, my 'rule of thumb' is to employ as good of user technique, 1/focal length shutter speeds or faster and recognize that I'll get few good-great images if my subject distance vs subject size will require more than 30-40% FOV cropping. Any more than that will usually result in merely an ID snapshot.

A good site to get an appreciation of these issues is by Mothman13 at-- http://www.texasmothman.com/photogra...ng/birding.asp

While there are exceptions to most everything, I believe recognizing and understanding these critical aspects and addressing them will go a long way to enjoying imaging with a long lens.


If anybody wants to add to this please do so.

Dave's response is pretty much right on, with little to add. 500 mm, or 800mm once you toss in the cropping factor of a D40, or 750mm with the Nikon smaller sensors, is a huge amount of focal length to keep steady. Technique becomes everything. One good side effect is that once you can shoot steady at these focal lengths, a 200 or 300 mm focal length becomes almost trivial handle with the same technique.

Enjoy the lens and the results!

Can I get the correct link? the one above does not work.

Jim

Hi guys, I'm kind of new to telephoto-ism. Here is my 2 cents. Recently I took a Muench Workshop and Marc Muench insisted that we stop down 2 stops from the telephoto len's widest apeture to get the best quality out of the lens. He was using a 70-200mm L IS on a large image sensor. Would anyone agree w/ that or disagree? I'm finding much more difficult to shoot any telephoto lens than what I normally do.

Immaterial of the focal length of the lens being used, anyone looking to crop more than 10% of any image for composition is snap shooting rather than taking photographs!

It is down to fieldcraft how large the subject is in the frame whether you are shooting with 200mm or 800mm, on a cropper or a full frame body!

So, learn to get closer without disturbing the subject before you lash out on super-long glass and blame the equipment!

Ian

Perhaps not practical with terrestial photos but shooting lunar landscapes with 1700 to 2400 mm telescope, one often has to open the shutter with a cardboard in front of the scope, then do exposure by moving the carboard, thereby eliminating all vibration. Vibration and prime focus are without parallel in extreme tele situations.

Steve, I don't know Marc, so I'm speculating his message in "getting the most out of the lens" probably is that stopping down a couple stops will sharpen up the image. Most (if not all) lenses are sharper stopped down than wide open. It's really more a matter of personal preference. That series of lenses is quite sharp wide open, a bit sharper still stopped down. Stopping down to f5.6 on an f2.8 IS lens isn't much of a handicap in good light, and if he was using a full-frame sensor he probably didn't have to worry about losing much quality at higher iso settings, so if stopping down two stops cost him too much for the lighting conditions, he could bump iso from 400 to 800 or 1000, for example, and get it back.

Taking workshops exposes photographers to techniques used by other photographers, and that's a good thing. I generally suggest that my clients take away all the advice/techniques they've been given, adopt what makes sense and works for them and discard what does not.

I'm finding much more difficult to shoot any telephoto lens than what I normally do.

I'm not really sure what you mean. Do you mean it's harder for you to shoot telephoto using Muench's technique? Do you mean you've lately run into some other trouble shooting telephoto? Can you explain in more detail?

Sorry about the bad link. Try this one.
http://www.texasmothman.com/photography-tutorials/birding/birding.asp

In my experience one of the most important factors in long lens image quality, and yet the most overlooked, is managing DOF. I've seen more of my own images and those of others miss the mark due to poor DOF management than any other reason. You're dealing with very shallow DOF when long lenses are shot wide open, yet that's the way most peope shoot them. If you're shooting wide open, always consider subject depth within the DOF, and if you can't match them up, be very very selective about which portions of the animal are inside and outside the DOF.

I would add one other issue that really comes into play shooting wildlife with long lenses and that is air quality. I know that at this time of year any high humidity or summer haze has a serious impact on any of my images taken at longer distances.

I have learned to concentrate on smaller stuff closer up when those conditions prevail. I agree with Ian that large crops are not good no matter the lens.

Thanks Steve, No it's just that I'm more used to shoooting at focal lengths of less than a 100 mostly wide angle shots. That was my first workshop so I was pretty much just taking what worked for me. Going from wide to tele is like learning DOF all over again.

As for what Marc Muench said, on the lens mentioned he said the that's the best aperature for image quality was 5.6 and then degrades from there as you stop down. The quality might not be very noticeable. I know that's contrary to what I would normally do since in Landscape photograpy you would want the DOF and I always shoot towards the lower end. I guess that would just make me more concious to how much DOF do I need if I want to stop down to f22 or lower.

Not doing much wildlife but I'de love to and will once I get around it.

Thanks Andre for the updated link