More of Macro Lenses for Rebel XT

[tylerwind]

I posted a question yesterday about macro lenses for my Rebel XT and many of

your graciously gave your input. Several of you asked for more information so I

figured I'd post it here in hopes that you will come back and revisit this and

offer more help. Any input is appreciated!

 

Yes, I am totally new to macro photography and honestly know very little about

it. I'm getting this lens because I need to do a project for work--I will be

shooting a subject that is about the size of a 16oz Coke bottle cap, not

living, and not moving. So, I assume any of them would be able to successfully

accomplish this task. The lens is being paid for by my work so money is not a

big concern (although I can't tell them I need a $3000 lens) but I do need to

purchase it soon which is why I'm in a hurry to get some help. I realize the

value in going to a store and trying many of them out but I'm not sure I have

time to do a thorough research of every lens and besides, I admit 100% that I'd

rather have a recommendation from you all that have done macro and used the

lenses than my own, very rookie, opinion. Although any macro would probably

serve my needs for work, I would like to get a versatile lens that I'll be able

to use to develop some macro skills and have some fun. What would I use it for?

Well, a few things come to mind--sometimes at the beach I'll find a small ghost

crab about the size of a fingernail that I'd like to photograph. I also think I

may enjoy insects and some flowers. I see many pictures of bees and

grasshoppers on the critique forum that I'd like to shoot. I know there are

specialized lenses for each type of shooting but what I would like is a good,

versatile lens that I can have fun with while learning and photographing a

variety of macro subjects. Like I said, the things that come to mind are small

beach critters, insects like bees and grasshoppers, and flowers. Does that help

at all?

 

Also, I see the point about limiting yourself by getting a lens that is 100mm

(or more) compared to 60mm. Obviously with longer lenses I'll run into the

problem of being "too close" and not being able to fit the subject into my

frame. Can anyone give me an idea about what I can fit into the frame from what

distance? For example, with a 100mm macro lens, how far would you have to be

away from an object like, say, a cell phone, to fit it into the screen. Is it

anything like my normal 100mm non-macro lens? I know the lenses are different

but I admit I don't thoroughly understand how (ie-the 1:1 ratio, etc.) and have

never used one myself. I don't want to end up with a lens that can't make a

small crab or insect big enough to produce an interesting image but at the same

time I don't want to have to stand across the room just to fit a spider into

the frame (I'm exaggerating, but you get my point).

 

Thanks once again for all the help--I appreciate it!

[phule]

<<so I figured I'd post it here in hopes that you will come back and revisit this and offer more help.>>

 

It would have been better to post this in the existing thread.

[tylerwind]

Rob-I did post it in the existing thread but hadn't received any responses so I was thinking those who were knowledgeable and willing to help may have already left their $.02 and wouldn't come back and visit. Not sure if that is correct or not, but that was the reasoning.

[byronlawrence]

the 100 mm macro will have the same feild of view as a normal 100 mm lens. so if you are familiar with how 100 mm looks then .. there you go. the macro lens may be slightly different due to build but not much.. also a Macro lens will allow you to get as close as necessary to get 1:1 scale.. ie.. the subject matter projected will be the same size as the subject matter in real life.. so a bottle cap will take most if not all of your frame.

 

i would suggest getting the canon 100mm macro. http://www.usa.canon.com/consumer/controller?act=ModelDetailAct&fcategoryid=155&modelid=7400

 

if you need to get closer to make a subject bigger.. look into extension tubes and if you need to get farther away, then take a step back. and if you need a wider angle.. trade it in for the 50 or 60mm lens. can't loose.

[byronlawrence]

btw.. the 60mm EF-S lens was probably designed to sell to people who had moved to a 1.6 crop DSLR and had had a 90-100mm macro lens that they were used to. the 60mm lens will have a similar field of view in a 1.6 crop dslr as the 90-100 mm macro lens did on the full frame 35mm camera.

[tylerwind]

Byron--I appreciate your input. I apologize up front for my ignorance but can you (or someone else) please help me understand something? So, if I put my 75-300 zoom on my camera, set it on a tripod, and set it at 100mm and focus on an object 10 FEET away, let's say a bottle cap that is 1 inch square. Then, I stay in the exact same spot and switch the lens to a 100mm MACRO, my images will appear the SAME size, correct? So, am I correct in saying that a "normal" lens and "macro" lens are exactly the same if you step a few feet away from an object but the only difference is that the macro will allow you to keep getting closer and closer to the object until it is life size? In other words, taking my example again, the Coke cap will look the same from 10 feet through either lens but as I move in closer, my "regular" lens will only be able to get closer enough to make the cap appear 1/2 inch big. If I used my macro from this distance they would it would also produce an image that appears 1/2 inch big. But, my macro could also keep moving closer and closer until the bottle cap appeared it's true size, 1 inch (ie-a 1:1 ratio).

 

If you have a better example to help me understand or can point me in the direction of a website that would help I would certainly appreciate it. I've read some things in the past but I still don't have a firm grasp on things.

 

THANKS!

[johnson_d.]

Tyler,

 

Yes, what you describe is correct.

[ramon_acosta]

You got it Tyler! Thats exatly how it is. And I second the canon 100mm.

[mendel_leisk]

I don't want to belabour Rob's point, but you really should have stayed within the orig thread. You're not alone in this jump to head of the line stuff, but it's detrimental to your orig thread. People respond to it, but now you've lost interest, wandered off, started a new one. There are threads here that meander on for months, or years. They are the most satisfying and worthwhile.

 

Ok, all done ;D

[alan_myers]

Hi Tyler,

 

For your Rebel, I'd recommend a 60-70mm macro lens. With the 1.6X crop sensor of your camera, this focal length range is effectively close to the 90 to 105mm "medium" length macro lenses we old timers used on our "full frame" 35mm film cameras and might use on a full frame digital today.

 

There are shorter macro lenses, too, but using these with full frame cameras often we'd end up casting a shadow on our subect, bumping right up against it with a lens hood, scaring away living subjects, overpowering them with a flash, etc. A focal length of 50-55mm on full frame was (is) often used on copy stands (coins and stamps, for example), but can be less convenient out in the field. However, on 1.6X camera, it's more like 80mm and not really a bad choice.

 

On the other hand, Canon's 50mm macro lens requires a secondary attachment to reach all the way to 1:1 magnification. Without it, it's a 1:2, or half-life-size lens. So, the EF-S 60/2.8 Macro lens (which I've not used yet, but have heard is designed to emulate the excellent EF 100/2.8 Macro) might be a more convenient choice, since it's able to focus all the way to 1:1 without any attachments.

 

The longer EF 100/2.8 and 180/3.5L Macro lenses are also capable of 1:1 without any attachments, but can be "too long" for many applications with a 1.6X crop camera (where they are "effective" 160mm and 288mm lenses, respectively). Long macro lenses are quite useful when shooting skittish living subjects - or poisonous, biting ones - but bring another set of challenges because they are much more difficult to keep steady and have extremely shallow depth of field, which can in turn requires even smaller apertures that mean even slower shutter speeds and/or more powerful flashes.

 

Best way to find out what you feel most comfortable with is simply to go to a camera store and try out the lenses on your camera. There's nothing like experiencing it for yourself.

 

The Canon website lists specifications for the closest focusing distance with their various macro lenses. That distance doesn't change when you put the lens on a 1.6X sensor camera. (But, it can be changed by adding an extension tube behind the lens, such as Canon's 12mm or 25mm... the longer the tube the closer you move to the subject and the higher the magnification.)

 

The distances are:

EF 50/2.5 = 0.8 feet

EF-S 60/2.8 = 0.65 feet

EF 100/2.8 = 1.0 feet

EF 180/3.5L = 1.6 feet

 

So none of these lenses will leave you "standing across the room" at their highest magnifictions.

 

However, keep in mind that you probably will not be using the closest possible distances, depending upon your subject. In other words, you might not actually be shooting 1:1.

 

This is because the image area of your camera is approx. 15mm x 22mm, not the 24mm x36mm of a full frame digital or 35mm film camera. In other words, if your subject is larger than 15mm across you will be shooting less than 1:1. Another way of describing this might be to say that the crop sensor camera gives the appearance of increasing any lens' magnification by 1.6X (i.e., 1.6:1 instead of 1:1). But, this is actually false. The only real difference is the size of the image area.

 

With a subject such you described originally, I suspect the EF-S 60/2.8 would probably work out best.

[mark u]

Just to throw some more confusion into the pot, most macro lenses change their effective focal length and aperture as they are focussed closer. For instance, the Canon 100mm f/2.8 USM becomes a little under 75mm at 1:1 - not dissimilar to the Canon 50mm f/2.5 and life size converter, which is about 70mm at 1:1. Lenses that don't extend when close focussed will shorten their effective focal length more than lenses that extend significantly. Life isn't quite as simple as some of the earlier answers make out.

 

The effect on aperture is also important, since at 1:1 the effective aperture is probably at least double the aperture indicated in the viewfinder (the instructions for the Canon 100mm state that the lens becomes f/5.9 when set to f/2.8 at 1:1). The viewfinder reports the aperture basis infinity focus with EOS cameras (Nikon cameras and lenses manage to report the effective aperture). The reason this is important is that you may find that you lose a lot of sharpness to diffraction, expecting that the shot is not diffraction limited and hoping for better depth of field and a "sharper" shot.

[tylerwind]

Thanks again guys! I'm understanding more and more but still don't have a firm grasp on everything. So we've established with a macro you can keep moving in (and, as Alan said with the 100mm Canon you can get as close as 1 foot from your subject) until you get a 1:1 ratio. Does a true 1:1 ratio on the Canon 100mm only occur at 1 foot from the subject? What's confusing me is exactly what the 1:1 ratio means in terms of subject size. I see macro shots all the time on photo.net of, for example, a bee. Obviously the picture is much bigger than the bee is in real life. Does 1:1 just mean that in relation to the other objects in the picture the subject is true to it's real size? Again, I apologize for my ignorance but I'm just confused on the 1:1 ratio and what that means as far as what I'll see when I put the picture on my computer. Does anyone have any example pictures of a 1:2 and a 1:1 of an object? That may help me. If the 1:2 is "half life size" and the 1:1 is "life size" then if you take the 1:2, crop it and enlarge it, won't you get the same image? Also, if you have two lenses, say 50mm macro and 100mm macro. Let's assume they are both 1:1. If you get as close to an object as possible with the 50mm lens and take the picture you can then produce the exact same picture with the 100mm lens, but just can do so from further away, correct? Will they produce the same image at their closest focal distance (which will be further for the 100mm)?

 

Grrrr...I apologize...I'm just not getting this completely (or at all!). You guys can feel free to laugh at me and tell all your friends that you know a stupid doctor that can replant your hand after a saw cuts it off but can't understand macro lenses! :) Thanks for the help and not giving up on me!

[robin_sibson1]

Tyler, the ratio is that between the size of the subject and the size of the image on the sensor. Obviously, the smaller the sensor, the more of it will be filled by an image of constant size, so x1 on a 10"x8" LF camera isn't quite as impressive as x1 on FF seen in the context of the whole image! This means that to produce an image that bears a constant relation to sensor size, you need a lower magnification on an APS-C format camera than on a FF camera. You can blow up the resulting image as much as you like on a monitor or a print, where it will often be many times the size of the subject, but since you usually view such an image from a distance proportionate to its size, this step is not usually incorporated into any statement about magnification.

 

I think it's time for you to lighten up, buy a macro lens, and get stuck in. You've done the homework, and from this point on a bit of practical experience will tell you more than you'll get from any other source.

[lester_wareham]

Tyler see my reply to your origional message http://www.photo.net/bboard/q-and-a-fetch-msg?msg_id=00JMa3&tag=

 

Also I have some tables of working distance and other useful stuff at http://www.zen20934.zen.co.uk/photography/Macro_Equipment.htm#Working%20Distance

[tylerwind]

Robin--Thanks for your response...I certainly appreciate the explanation! Lester, your comments on my other post were most helpful--thank you for leaving them and being so thoughtful and informative. You obviously know what you're talking about and I think I'm going with your advice (which several of you have kindly echoed) and getting the Canon 100mm macro. Thanks!

[tylerwind]

A few more questions I've encountered while learning and thinking--do you need a lens bracket mount for a tripod for the Canon 100mm macro lens? Or, can you attach the camera to the tripod like I do with my other lenses. Also, how does the weight and length of this lens compare to others? I have a Canon 75-300 zoom--is the 100mm macro bigger/heavier than that?

 

Also, some of you mentioned flashes--why are they so essential with macro? If I'm shooting a grasshopper in the middle of a yard in broad daylight will I need a flash? I understand that at such a close distance you may have to shut the lens down a bit to get enough DOF which will obviously prolong your shutter speed. Am I correct in assuming that the shutter speed will be too slow if the subject is moving? Or is it just hard to shoot insects with a tripod so it's easier if you can hand hold the camera, which will require a faster shutter. If you are shooting objects that are stationary, like flowers, there is no need for a flash, is there? I'm new to this and trying to learn so I really appreciate all the help.

[lester_wareham]

Tripod rings (TMA) are useful for changing orientation (land/port) fast without having to adjust the tripod, as it rotates the lens around the optical center. Other this the 100mm macro is light enough to just mount via the camera, obviously a Kirk or RSS L-Plate will help with this but is not essential either.

 

Some the independent lenses come with the TMA, of the Canon lenses only the 180mm and MP-E 65mm do. The 60mm and 50mm can not use them is my understanding. I would not go to the expense of it for the 100mm but I got one with the MP-E (they all use the TMA-B) and bought the cheap plastic adaptor needed, see this page http://www.zen20934.zen.co.uk/photography/macroMTF/tma%20for%20100mm.htm.

 

As for flash, the thing about macro work is the magnification, this has three technical impacts, small depth of field possibly a mm or less requiring substatial stopping down, light loss due to magnification, magnification of movement - a tiny breeze may cause a mm of subject movement which my be a substatial part of the DOF. Thus the flash provides plenty of light and a very shot exposure freezing subject movement. More on macro DOF and light loss here http://www.zen20934.zen.co.uk/photography/dof/dof.htm#DoF_with_Macro_Photography

 

Ambient light work with insects is possible and is very rewarding when it works. Things like the Wembley Plamp help keep branches the subject is on still, things like Lasolight folding light reflextors make good wind shields. Of course all this can scare off insects.

 

If you shooting things that don't move then use a tripod and natural light, but remember the slightest breeze can be a problem.