[PenPusher]

I expect I have missed quite a few more lenses as well, the main reason I showed the list at all was to explain why I hadn't credited 2 shots to this lens and 7 to another etc. etc. and just shoved them into groups as I would have been at it all year.

I am actually quite surprised at the variety of macro lenses used, being kind of a specialist subject area I would have expected a much smaller number, though of course you can use them for other purposes as well.

The other thing that surprised me is the small number of images posted with the DA35mm F2.8 Ltd. macro which I have always understood to be a highly regarded lens.

CD

[jacamar]

The other thing that surprised me is the small number of images posted with the DA35mm F2.8 Ltd. macro

I posted a few just recently (#2692, 2699, 2706). There are more at https://www.pentaxforums.com/lensreviews/hd-pentax-da-35mm-f2.8-limited-macro.html
(edit) Aslyfox's point below that longer focal length means you can be further way from the subject is correct, but with the 35mm you can compensate for this to some extent by cropping (and retaining a greater depth of field than a longer lens) because it's so sharp.

[aslyfox]

. . . The other thing that surprised me is the small number of images posted with the DA35mm F2.8 Ltd. macro which I have always understood to be a highly regarded lens.
CD

perhaps an explanation may be the difference between what I call studio macro and field macro

now don't get me wrong as I realize that I am a newbie in photography especially macro but I thought the shorter the focal length of the lens

35 mm vs. 50 mm vs 100 mm etc

for macro, the closer you have to be to the " target ".

in other words, in the " field " where I am trying to capture " pollinators " in action,

Pollinators in action - Page 23 - PentaxForums.com


my D FA 100mm Macro 2.8 ( or longer lens )allows me to be further away from my " target " and thus less intrusive on it and its environment

does this make any sense.

If I am correct, then the shorter focal length lens are better for inanimate objects or " studio " macro where you have more control

of course, a seasoned experienced macro photographer [ jacamar ] probably can use what ever focal length they want for any situation


does this make any sense?

[PenPusher]

I should have said if anybody wants me to update the list just give me the full details of the lens in question

CD

---------- Post added 11-08-2017 at 02:31 PM ----------

perhaps an explanation may be the difference between what I call studio macro and field macro

now don't get me wrong as I realize that I am a newbie in photography especially macro but I thought the shorter the focal length of the lens

35 mm vs. 50 mm vs 100 mm etc

for macro, the closer you have to be to the " target ".

in other words, in the " field " where I am trying to capture " pollinators " in action,

Pollinators in action - Page 23 - PentaxForums.com


my D FA 100mm Macro 2.8 ( or longer lens )allows me to be further away from my " target " and thus less intrusive on it and its environment

does this make any sense.

If I am correct, then the shorter focal length lens are better for inanimate objects or " studio " macro where you have more control

of course, a seasoned experienced macro photographer [ jacamar ] probably can use what ever focal length they want for any situation


does this make any sense?

Yes, but unless I am mistaken, which is quite possible, the shorter the focal length the greater the depth of field meaning that you do not have to stop down as much as you would on a longer focal length to get everything in focus and the brighter the image the easier it is to see what you are doing.

[aslyfox]

. . .

Yes, but unless I am mistaken, which is quite possible, the shorter the focal length the greater the depth of field meaning that you do not have to stop down as much as you would on a longer focal length to get everything in focus and the brighter the image the easier it is to see what you are doing.

hadn't thought of that before, the relationship between depth of field and focal length :

" Focus enables you to isolate a subject and specifically draw the viewer’s eye to exactly where you want it. . . .

The first thing to understand about focus is depth of field . . .

Depth of Field (DOF) is the front-to-back zone of a photograph in which the image is razor sharp. . . .

DOF is determined by three factors – aperture size, distance from the lens, and the focal length of the lens. Let’s look at how each one works. . . .

Distance from the Lens

The last element affecting depth of field is the distance of the subject from the lens – you can adjust the DOF by changing that distance.

For example, the closer an object is to the lens (and the focus is set on that object) the shallower the DOF. Conversely, the reverse is true – the farther away an object is and focused on, the deeper the DOF. Changing the distance to subject is the least practical way to manipulate the depth of field, and by changing the distance from a subject to the lens, you immediately change your image’s composition. To maintain the compositional integrity of the shot, but still have the change in DOF from a distance, you can change the focal length (either by changing lenses or zooming in). . . .

Why does changing the focal length negate the effects on DOF? This is because the visual properties of a given lens either provide either greater DOF (shorter lenses) or shallower DOF (longer lenses). The physical properties of a lens at a given focal length also affect the depth of field. A shorter focal length lens (say 27mm) focused at 5 meters, set at f/4 has a deeper DOF (perhaps from 3 meters in front and 20 meters behind) than a longer focal length (say 300mm), also set at f/4 focused at 5 meters. The 300mm lens has a remarkably shallow depth of field."

Focusing Basics | Aperture and Depth of Field

[jacamar]

A wind-eroded beach pebble: K-3, Pentax DA 35mm f2.8 Ltd macro with off-camera flash, minimal cropping

[PenPusher]

In Herbert Keppler's The Asahi Way 3rd Ed 1969 depth of field tables p331 onwards is an example of the difference between 35mm and 50mm lenses at F4.0 when focussed at 18" - 457.5mm which is the shortest distance he gives for both lenses:

35mm Super Takumar F2.0 1.54' to 1.67' = 0.13' or 469.7 to 509.35mm DoF = 39.65mm

50mm Super Takumar F1.4 1.56' to 1.64' = 0.08 or 475.8 to 500.20mm DoF = 24.4mm

Which shows that the depth of field advantage will lie with a shorter lens.

Undoubtedly a macro lens will focus closer, the longer the lens the greater working distance but as a macro lens could be considered a standard lens on extension tubes the depth of field will decrease with the amount of macro extension, well I think it will anyway but then once maths went beyond 2 + 2 = 4 my brain switched off.

CD

[aslyfox]

I don't do math

so back to photos

uncropped

cropped

this guy has had it tough, check out the damage to the wings

[WPRESTO]

The supposed rules of thumb for DOF: if the f-stop and the magnification (=reproduction ratio) are the same, then the DOF is the same regardless of focal length. If the f-stop and the distance lens-to-subject are the same, then a shorter focal length lens will have a greater DOF.

[RockvilleBob]

A couple of focus stacked orchids taken at Rawlings Conservatory in Baltimore MD

[mojoe_24]

Focus stacked?

[Canada_Rockies]

Bob, those orchids are absolutely gorgeous! Thank you for letting us see them.

[RockvilleBob]

Thank you. Yes they are focused stacked, taken with fill flash. Rawlings Conservatory in Baltimore is a great place for photography. While it is small, there is a lot of space to set up a tripod. There are not many visitors during the week and the staff is very accommodating.

[rgknief60]

2 image pixel shift focus stack, cropped. K-1 & FA 100mm macro.

Increased magnification of tip of shell posted here.


Shell

[dadipentak]

Vivitar Series 1 90mm/2.5 on K-1