newsguygeorge Loc: Victoria, Texas

I’ve been shooting close ups with an AF-S Micro Nikkor 85 mm prime lens. It has a very shallow depth of field even when stopped down to smaller apertures. Getting a fully sharp photo can be challenging. Talking with a friend, we got to wondering whether a longer micro/macro lens would have a wider depth of field. Understanding this could inform a decision about acquiring another lens.

Can anyone elucidate on this issue?

Ysarex Loc: St. Louis

At the magnification you're working DOF will be similar regardless of the focal length of the lens. So changing to a different focal length lens isn't going to do any good in terms of DOF. In simplified terms DOF is a function of magnification and f/stop. Magnification is a function of lens focal length and subject distance. Change focal length and then change distance to keep the same magnification and at the same f/stop DOF doesn't change.

TriX Loc: Raleigh, NC

Perhaps a different approach and investigate focus stacking if practical for your subjects.

Soul Dr. Loc: Beautiful Shenandoah Valley

The only way to really get good depth of field using a true macro lens is by focus-stacking.
A longer length of the lens is not going increase the depth of field, it just increases the distance to subject the lens can be to focus.

will

wjones8637 Loc: Burleson, TX

Far from an expert, but using the Digital Depth of Field app for apps-c sensors I found these values. Not what I expected.

All are for f22 at a distance of 2’.
85 mm. 1.5”
105 mm. 1.0”
150 mm. 0.4”
50 mm. 4.7”

Bill

robertjerl Loc: Corona, California

Longer macros have less depth of field just like teles have less DOF than wide angles. The solution most use is "Focus Stacking"=several images with the focus on different parts of the subject spaced so the DOF overlaps then blended in software to produce a sharp image. I make the first focus just in front of the subject and the last just the other side of the subject.
Landscape photographers often do the same thing to produce those awesome vistas where everything from the ground just in front of the photographer to the horizon is in focus.
Our local camera store sponsors classes from time to time - often with factory reps, pro photographers and/or professors of art and photography as instructors and I took one on macro photography where one of the instructors was a specialist in Product/Advertising photography who showed us a custom guitar made by Fender for some star that was seen looking down the length of the guitar from the strap button, the body, up the neck to the head with the tuning keys and the whole thing was razor sharp. He said it took 150 stacked images with a macro lens to produce the final image.

DavidM Loc: New Orleans, LA

Have a look at these links... Also the canon R5 and R6 have focus stacking features built in.

https://www.outdoorphotographer.com/tips-techniques/photo-tip-of-week/depth-field-macro-photography/

https://www.dpreview.com/articles/3064907237/depth-of-field-in-macro-photography

https://digital-photography-school.com/tips-for-depth-of-field-control-in-macro-photography/

https://photographylife.com/macro-photography-tutorial/2

SuperflyTNT Loc: Manassas VA

Most manufacturers now make models that include focus stacking features.

SuperflyTNT Loc: Manassas VA

Not really useful to this situation, for one thing we’re looking at distances much less than 2’. For another if you change the focal length you need to change the distance you’re working from.

Canisdirus

Your lens is known to be very sharp.
It is designed for a crop sensor body...so DOF should be pretty good.

Anyway, the rule of thumb for DOF is a longer lens with the smallest diameter will yield the greatest DOF.
The larger the diameter...the less DOF.

Thomas902 Loc: Washington DC

"...a decision about acquiring another lens..." George the issue is with workflow, not your kit.
Albeit camera vendors would be more than happy to lighten your wallet...

Like so many other posters have mentioned in your query... Focus Stacking is an industry standard for increasing DOF... Please Note: This can be an arduous process i.e. not a trivial task. I highly recommend investing some quality time in UHH's "True Macro-Photography Forum" https://www.uglyhedgehog.com/s-102-1.html There you will find 14 stellar tutorials on and about Macro-Photography. They will give you a far better perspective on your query than here in the Main Photography Forum.

That said, Focus Stacking is but one of the methodologies commercial shooters deploy when faced with a DOF issue. Another very elegant solution is the use of the Scheimpflug principle which states that the sensor plane, lens plane and plane of sharpest focus must all intersect along a line. In your lens this intersection is actually a single point since the line is perpendicular to your sensor. When the Scheimpflug principle is combined with a "Tilt" lens then the "Hinge" or "Pivot Rule" of the "Tilt" define the location for the plane of sharpest focus, While the tilt effect does not necessarily increase depth of field—it just allows the photographer to customize its location to better suit their subject matter. This DOES increase the APPARENT depth of field.

As a portrait photographer I'm keenly interested in "Tilt" lenses... Which btw, can be used to reduce apparent depth of field, and can be particularly useful for portraits when a wide aperture is insufficient, or when one wishes to focus on only part of a vertical object.

George I'm not suggesting you purchase a Tilt/Shift Lens... Just want you to realize how incredibly complex commercial photography actually is IN PRACTICE not in theory... I assist many commercial archetectual shooters and they do indeed often deploy Tilt/Shift optics to increase "apparent" depth of field and straighten diverging/converging vertical lines...

Keep shooting George... and remember your first 10,000 images are likely going to be your worst... Better results come with time; practice and patience for those who hold a steady course...

Wishing you all the best on your macro journey George...

imagemeister Loc: mid east Florida

As mentioned, APPARENT DOF can be extended using a tilting macro lens. Canon makes 3 different focal length tilt-shift MACRO lenses - but they only go to 1:2 natively - for around $2K each ! I made my own using enlarging lenses.....https://www.uglyhedgehog.com/t-633755-1.html

I guess focus stacking is cheaper !
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newsguygeorge Loc: Victoria, Texas

Thanks, folks. My question is well answered.

JRiepe Loc: Southern Illinois

I, at one time, shot mostly macro but do very little now. If you're looking for the absolute best detail I suppose focus stacking is the answer but I've never done it. I get all the detail I want or need by backing off the subject a bit and then cropping. There is no written rule that you must always shoot at 1:1 magnification.

imagemeister Loc: mid east Florida

Yes, you can also be further away and "magnify" by cropping and using AI pixel enlargement software .....
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