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200mm with +3 diopter or 200mm Macro

Published : 2nd February 2007

I have been asked to compare and choose the better of the two, a 200mm T2 Nikon with a +3 Diopter or a 200mm T4 Macro Nikon (unfortunately not a Zeiss/Arri or a Pana) on an Arri 16SR Super 16. Any words of wisdom? I have opted for the 200mm with diopter because the magnification is higher (at same distance) and the minimum focus is closer by 6 inches. Will one provide sharper images than the other?

While there is stop loss with the macro (I'll probably be looking at 2 stops compensation for these shots), is there stop loss using the diopters on a 200mm. Do I need to compensate for the magnification or is there something else causing the stop loss on macros? I think the DOP would prefer to light these macro shots to a T2 rather than have to light to a T8!

Cheers

Mark W Lunn
1st AC
Vancouver


I have been asked to compare and choose the better of the two, a 200mm T2 Nikon with a +3 Diopter or a 200mm T4 Macro Nikon (unfortunately not a Zeiss/Arri or a Pana) on an Arri 16SR Super 16. Any words of wisdom? I have opted for the 200mm with diopter because the magnification is higher (at same distance) and the minimum focus is closer by 6 inches. Will one provide sharper images than the other?

While there is stop loss with the macro (I'll probably be looking at 2 stops compensation for these shots), is there stop loss using the diopters on a 200mm. Do I need to compensate for the magnification or is there something else causing the stop loss on macros? I think the DOP would prefer to light these macro shots to a T2 rather than have to light to a T8!

cheers

Mark W Lunn
1st AC
Vancouver


I own both these Nikon 200mm lenses but have only used them for stills.
I would also suggest that the macro/micro Nikkor will be superior to the tele Nikkor with a 3 dioptre lens in the close-up situation.

You will definitely require exposure compensation for your close-ups regardless of the glass you use.

I would also suggest that the 200mm F2 tele with a 3 dioptre close up lens used at maximum aperture for close up work will have an EXTREMELY SMALL depth of field!!!

All the best

Steve Morton
Scientific Imaging
Monash University
Melbourne
Australia


Mark W Lunn wrote:

class="style15">> While there is stop loss with the macro (I'll probably be looking at 2 >stops compensation for these shots), is there stop loss using the >diopters on a 200mm.

There is no stop loss with a diopter

class="style15">> Do I need to compensate for the magnification or is there something >else causing the stop loss on macros?

Yes, the design of the lens system.

class="style15">> I think the DOP would prefer to light these macro shots to a T2 rather >than have to light to a T8!

He might change his mind when he sees the DOF or rather the lack of DOF.

T8 is not much of a challenge to meet for macro work.

Brian Heller
IA 600 DP


Mark W Lunn wrote :

class="style15">> ...is there stop loss using the diopters on a 200mm. Do I need to >compensate for the magnification or is there something else causing >the stop loss on macros?

Once you focus down into the macro range, you lose exposure as the lens moves away from the film plane. However, the addition of even a +3 diopter does not cause you further loss of exposure, it just optically shifts the focus closer (but not by moving the lens group further from the film plane). But they're usually not as sharp/contrasty as using a decent macro instead, and any distance markings for focusing further away are no longer valid once you've added a diopter.

Either way, for most purposes, you get better results shooting it at higher stops, most decent macro lenses start at t2.8 in the macro range, and its usually not difficult at all to light a macro shot to something better than a 2.

Mark Doering-Powell
LA based DP


Brian Heller wrote:

class="style15">> There is no stop loss with a diopter

Sorry due to a mishap involving a kitten, coffee, and my keyboard I was unable to add that "There is no stop loss with a diopter under normal circumstances." With a + 3 diopter and a 200 mm Nikon telephoto lens, you will not be able to focus close enough to be shooting macro (1 TO 1).

Exposure compensation is required when the subject you are shooting appears larger on the film plane than it actually is. This is generally known as the magnification factor; the greater the magnification, the more exposure compensation is required.

In any event, you will get far better results - sharper, less distortion, colour fringing,etc. with a lot less hassle if you use a macro lens.

I believe David Samuelson's "Hands On Manual" contains all of the relevant formula for diopters and macro work, and a -- no doubt -- more cogent explanation. Mine is on loan to a friend.

Brian Heller
IA 600 DP


Thanks Angelo, you wrote :

class="style15">>>the lens is quite sharp, but minimum focus is 9 feet!

I was able to get min focus down to 2' with the plus 3 diopter

class="style15">>>Usually, the heavier the diopter, the heavier the aberrations.

Also, the macro has a front element protected by a round hood and is about 1 and 3/4 inches in diameter, the Nikon with the +3 has a convex piece of glass out front that is about 6 inches in diameter. I know which one will get flares first!

Mark W Lunn
1st AC
Vancouver


Brian Heller wrote:

class="style15">>>Exposure compensation is required when the subject you are >>shooting appears larger on the film plane than it actually is. This is >>generally known as the magnification factor; the greater the >>magnification, the more exposure compensation is required.

So, the exposure compensation would be the same, given the magnification ratio is the same. For example, the T2 Nikon with the plus 3 at 1:1 magnification would require a compensation of 2 stops; the same as the macro would require.

class="style15">>>With a + 3 diopter and a 200 mm Nikon telephoto lens, you will not be >>able to focus close enough to be shooting macro (1 TO 1).

I was able to focus on a subject at 2' away, which produced a 1:1 magnification ratio. DOF was about half a millimetre. However, the image was ghostly - a lot of bounced light back off the chart hitting the BIG convex plus 3 diopter.

So, if we know when a macro insert is coming up, we'll have the macro. (budget is a concern, so we can't carry it full time, otherwise this whole thread would be moot).

Thanks everyone for your input

Mark W Lunn
1st AC
Vancouver


Brian Heller wrote :

class="style15">> Exposure compensation is required when the subject you are >shooting appears larger on the film plane than it actually is.

Brian,

Exposure compensation is required well before that point.

Stephen Williams DoP

www.stephenw.com


Steven Morton writes :

>The 200mm F2 tele with a 3 dioptre close up lens used at maximum >aperture for close up work will have an EXTREMELY SMALL depth of >field!!!

If you need more DOF and working distance isn't a concern, why not go to a shorter macro?

Tim Sassoon
SFD vfx & creative post
Santa Monica, CA


Stephen Williams wrote :

>Brian,

>Exposure compensation is required well before that point. (1 to 1)

Sorry if I wasn't being clear. I meant when using diopters. If using a macro lens or extension tubes, exposure compensation is definitely required long before 1 to 1.

Brian Heller
IA 600 DP


Tim Sassoon wrote :

> If you need more DOF and working distance isn't a concern, why not go >to a shorter macro?

The DOF is not related to the focal length of the lens, so going to a shorter macro won't help in any way.

Stephen Williams DoP

www.stephenw.com


>>The DOF is not related to the focal length of the lens, so going to a >>shorter macro won't help in any way.

I may be nuts, but shouldn't the same magnification at the same stop with a shorter lens have more DOF?

Tim Sassoon
SFD vfx & creative post
Santa Monica, CA 90405


 

Tim Sassoon wrote:

>>If you need more DOF and working distance isn't a concern, why not >>go to a shorter macro?

Because it won't work.

If you require the subject to remain the same size, then the depth of field will remain the same -- provided you are working at the same f: stop. In other words if you want your subject to be the same size, by changing to a shorter lens you will have to move the camera closer to your subject; in so doing, you will be right back where you started in terms of DOF.

The only way to increase DOF in that case is to stop down. DOF is not a function of focal length. Of course, focal length will affect the field of view. However, in macro work, changes in the field of view are not usually very apparent.

Brian Heller
IA 600 DP


Brian Heller writes :

>>Because it won't work

You're right, I'm nuts.

Tim Sassoon
SFD vfx & creative post
Santa Monica, CA 90405


Tim Sassoon wrote :

> but shouldn't the same magnification at the same stop with a shorter >lens have more DOF?

Tim,

At the same F stop and image size on the negative the DOF is the same.

Stephen Williams DoP
Zurich


>I may be nuts, but shouldn't the same magnification at the same stop >with a shorter lens have more DOF?

To get the same screen size with the shorter lens instead, you'd have to move closer and focus closer, thus your DOF drops off again.

David Mullen, ASC
Los Angeles


Tim Sassoon wrote:

class="style15">>I may be nuts, but shouldn't the same magnification at the same stop >with a shorter lens have more DOF?

No, you're not nuts. But it is a commonly misunderstood concept. In fact, many photo books will tell you that a WA lens has more DOF than a telephoto, and then proceed to demonstrate that fact with shots of the same subject taken from the same position with a series of different focal lengths. The problem is the subject size varies accordingly -- and tremendously.

If the subject size is kept the same, which requires moving the camera, and the f: stop remains the same, then the DOF will be the same no matter the focal length of the lens. Try it for yourself.

Brian Heller
IA 600 DP


1/. There is indeed light loss through a diopter lens. However, it's very little loss, and not worth worrying about for the most part. Far less than half a stop.

2/. A "macro" lens is basically the same thing as taking a standard lens and putting it on an extension tube. If you're using primes, there is no reason not to just use an extension tube. The fancy thing about the "macro" design is that you can build a zoom that tracks in the macro configuration, whereas putting a zoom on an extension tube is a recipe for trouble.

3/. The _Kodak Darkroom Dataguide_ has a nifty chart showing how much you need to open up the lens to compensate for light loss when using extension tubes…and it also gives the magnification ratio that you get as well.

4/. Does anyone still use reversing rings? That's always a fine trick to get you up very close without light loss.

Scott Dorsey
Kludge Audio
Williamsburg, VA. 23185


Brian Heller wrote :

> The only way to increase DOF in that case is to stop down. DOF is not a >function of focal length.

Brian has pointed this important lesson many times, but it's easy to forger.

Anyone have a simple Excel spreadsheet for calculating macro DOF?

I am working at magnifications of between 1:1 and 5:1...

Jeff Kreines


Scott Dorsey wrote:

>A "macro" lens is basically the same thing as taking a standard lens >and putting it on an extension tube.

Not to quibble, but modern macro lenses are designed for flatness of field.

>If you're using primes, there is no reason not to just use an extension >tube.

That is unless you are using any lens that focuses internally and many modern primes do-- Zeiss Super Speeds, Cooke S4s, Primos, etc.

Again, unless you have a lot of time or have had a lot of practice with them, extension tubes are a real PITA.

And, Panavision and Pl mount extension tubes tend to be hard to find items ;o)

>The fancy thing about the "macro" design is that you can build a zoom >that tracks in the macro configuration, whereas putting a zoom on an >extension tube is a recipe for trouble.

Sure is, since zoom lenses also focus internally. To get anywhere with extension tubes, you need to use lenses that focus by racking in and out physically from the film plane.

Brian Heller
IA 600 DP


Mark wrote :

> I was able to get min focus down to 2' with the plus 3 diopter

I was quoting the min focus of the bare lens itself!

Angelo Sartore
1st. AC
Melbourne
AUSTRALIA

ADOPT, ADAPT, INVENT, DESTROY !


Jeff Kreines wrote :

>Anyone have a simple Excel spreadsheet for calculating macro DOF?

> I am working at magnifications of between 1:1 and 5:1...

I would think that a math whiz such as yourself with have that at his fingertips -- I sure don't know of any.

However, if you can locate a copy of Applied Depth of Field (long out of print), the author, Mr. Alfred Blacker, has already done all the arithmetic, and he has thoughtfully included some 200 pages of DOF tables for Near Object Photography with degree of magnification attached.

Brian "Will DOF be on the Menu for the Kinetta?" Heller
IA 600 DP


OK, I'm a little late to the party but if you do go the diopter route you'll be happier with Achromats (multi element diopters). They give beautiful results and keep you much closer to the look of a "clean" lens.

Best,

Anders

:::::::::::::::::::::::::::::::
Anders Uhl
Cinematographer
ICG, New York


Mark W Lunn wrote :

> So, the exposure compensation would be the same, given the >magnification ratio is the same. For example, the T2 Nikon with the plus >3 at 1:1 magnification would require a compensation of 2 stops; the >same as the macro would require.

Ah, no. Normally a diopter requires no exposure compensation. However, in my experience, when the magnification exceeds 1 to 1, underexposure can start to become an issue.

Macro lenses require exposure compensation long before reaching 1 to 1.

> I was able to focus on a subject at 2' away, which produced a 1:1 >magnification ratio. DOF was about half a millimetre. However, the >image was ghostly - a lot of bounced light back off the chart hitting the >BIG convex plus 3 diopter.

Are you sure it was 1 to 1? Just quickly doing the math I get around 0.5 magnification at those specs. At f: 2.0 the DOF was about the thickness of a piece of paper.

> So, if we know when a macro insert is coming up, we'll have the macro. >(budget is a concern, so we can't carry it full time, otherwise this whole >thread would be moot).

See what Anders Uhl had to say about achromatic diopters. That might be the best solution. I didn't realize that they were available to fit larger lenses.

Sorry for the delay in replying, Lyris said I had exceeded my daily allowance.

Brian Heller
IA 600 DP


Brian wrote:

> I didn't realize that they were available to fit larger lenses.

I'm not 100% sure what the largest size is, but they are readily available in 138mm. It would certainly work with a Century 2000 Canon T2 or a 25-250 which might not be a bad way to go in terms of flexibility.

Another benefit of the achromats is that they maintain zoom performance better than a standard single element diopter. They will help with contrast and flare as they are real lenses and not just a magnifying glass in front of the lens.

Best Regards,

Anders

::::::::::::::::::::::::::::::::::::::::::::::::::
Anders Uhl
Cinematographer, NY
The DOP shop
http://www.thedopshop.com




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