[Froth Ninja]

Advice please hive. I have a K3 and two lens - a SMC DA 18-55mm AL WA and a HD DA 55-300mm ED WR
What I am looking for is a prime lens that I can use in the field for flower and insect photos. Depth of field is important as the subjects often move and with the lens I have I get a lot of duff shots. Often there is only once chance to snap the subject before it vamooses. Preferably the lens would be one that is also weather proof as I am often caught out in the rain.
I tend to use the 18-55 but I have to get very close, often frightening the subject away and the depth of field is problematic especially in even mildly breezy conditions. I confess to not understanding the jargon used on the website, especially initials like CA. I have looked at various threads and reviews but seen no real answers, but was wondering what people would recommend. Would a 100mm macro do the job? I look forward to your expert opinions, thank you.

[pepperberry farm]

geez..... this looks familiar....

prime, prime, everywhere a prime... - PentaxForums.com


(I am kidding - this my own prime-lens-adventure)


sounds like the D FA 100/2.8 Macro would be perfect for you.....

[bertwert]

From your description it sounds like you're looking for a macro lens - and for insects, the more working distance (distance from camera to subject) the better, so a 100mm macro would suit you. There's plenty of decent ones out there - it would help to know your budget as well. As far as WR, if that's a must, you're pretty much limited to the D FA 100mm Macro WR - you can read the in-depth review here on PentaxForums, as it holds lots of great information: Pentax-D FA 100mm F2.8 WR Macro Review - Introduction | PentaxForums.com Reviews

[pepperberry farm]

the Irix 150mm f2.8 Macro is also weather-sealed....

[bertwert]

the Irix 150mm f2.8 Macro is also weather-sealed....

Good point...

Irix 150mm F2.8 Macro Review - Introduction | PentaxForums.com Reviews

[johnyates]

There's a Tamron 90 Macro in the Marketplace. No affiliation, no endorsement, just saying . . . K-70 and various lenses - PentaxForums.com

[aslyfox]

if price is an issue

you may want to look for the earlier version of the D FA 100mm F2.8 Macro

Description:
This lens features a clamp and 1:1 macro magnification. Optically it is the same as the predecessor, the smc Pentax-FA 100mm F2.8 Macro, and optically also the same as the Weather Resistant successor.

Read more at: SMC Pentax-D FA 100mm F2.8 Macro Reviews - D FA Prime Lenses - Pentax Lens Reviews & Lens Database

the FA 100mm F2.8 Macro

Description:
The SMC Pentax-FA 100mm F2.8 Macro is a high-quality macro lens designed to be well above the SMC Pentax-FA 100mm F3.5 macro in image quality. It features a clamp and a focus limiter. The optics are seated that far from the front that no separate lens hood is required.

Optically this lens is identical to its F-series predecessor and the D FA-series successors.

Read more at: SMC Pentax-FA 100mm F2.8 Macro Reviews - FA Prime Lenses - Pentax Lens Reviews & Lens Database F D FA 100mm F2.8 Macro

or the F 100mm F2.8 Macro

Description:
This was the first in a series of 100mm autofocus macro lenses from Pentax. The subsequent versions (FA, D FA) have the same optical formula. The optics are seated that far from the front that no separate lens hood is required.

Read more at: SMC Pentax-F 100mm F2.8 Macro Reviews - F Prime Lenses - Pentax Lens Reviews & Lens Database

[bertwert]

There's a Tamron 90 Macro in the Marketplace. No affiliation, no endorsement, just saying . . . K-70 and various lenses - PentaxForums.com

Second comment says the 90 is sold... (and if it wasn't, it would now be sold to me... )

[jddwoods]

Pentax has three macro choices: DA 35 Limited, DFA 50 macro and DFA 100 macro WR. All are very sharp, the 50 is likely to be the least expensive purchased new. However, only the DFA 100 macro WR is weather resistant and is the best choice for taking pictures of small skittish creatures such as insects. Earlier versions of the 100 macro may be available used but none are weather resistant.

[aslyfox]

Pentax has three macro choices: DA 35 Limited, DFA 50 macro and DFA 100 macro WR. All are very sharp, the 50 is likely to be the least expensive purchased new. However, only the DFA 100 macro WR is weather resistant and is the best choice for taking pictures of small skittish creatures such as insects. Earlier versions of the 100 macro may be available used but none are weather resistant.

other differences blades are rounded not straight, no focusing clamp or limiter

Pentax-D FA 100mm F2.8 WR Macro Review - Introduction | PentaxForums.com Reviews

[hcc]

+1 for a macro-lens around the 90-150 mm focal length range.
The Pentax DFA 100mm (several version) is a solid choice, albeit a bit pricy. The Tamron 90mm and Sigma 105mm are two other options.
If price is an issue, consider a 2nd hand purchase, from trusted sources, like PF marketplace, KEH.com, BH (2nd hand) and Adorama (2n hand)
On another hand, if price is not an issue, the best macro lens IMO is the Vouigtlander APO Lanthar 125mm f2. Rare, expensive, but superb / astonishing IQ (and I speak from experience as i have one).
My 5 cents...

[Froth Ninja]

Thanks for the info so far folks - relieved to see I was heading in the right direction and also relieved to see there is some choice. Availability may be another issue. Suspect seond hand is going to be likely

[bertwert]

Thanks for the info so far folks - relieved to see I was heading in the right direction and also relieved to see there is some choice. Availability may be another issue. Suspect seond hand is going to be likely

As far as second hand - definitely check out the marketplace here. You can also put up a wanted ad.

[Snafu711]

Regardless of which lens you pick: don‘t expect a great depth of field when shooting at small distance! This is one of you requests, but it’s a physical law that narrowing distance to the object will narrow DoF.

I can recommend the FA 100/2.8 Macro which I use frequently to shoot flowers and insects.

[aslyfox]

Thanks for the info so far folks - relieved to see I was heading in the right direction and also relieved to see there is some choice. Availability may be another issue. Suspect seond hand is going to be likely

the OP might want to review this article and video:

The Advantages of a Dedicated Macro Lens
Achieving lift-size magnification
By PF Staff in Tutorial Videos on Apr 4, 2016

The 18-55mm kit lens is versatile, but it can't fill every role perfectly. If you're a beginner interested in close-up (macro) photography, we recommend that you consider adding a dedicated 1:1 macro lens to your lens collection. Watch the video below to learn about the benefits of a true macro lens:L . . .

Read more at: The Advantages of a Dedicated Macro Lens - Tutorial Videos | PentaxForums.com

a true 1:1 macro lens is also good for other purposes, it isn't a just a specialty lens

for example the 100mm F2.8 macro variants offered by Pentax make a good short telephoto lens as well