[Madaboutpix]

I should have my new HD Pentax D FA* 50mm F1.4 SDM AW some time next week. If anyone has any pointers about how to adapt this lens to my K3 iii crop camera, I would appreciate it.

Um, what do you mean "how to adapt"? You put the lens on your camera, turn on the latter, make sure that the AF switch on the lens is set to "AF", and just prepare to be amazed - it should work straight away as is. About the finest 75mm-equivalent-FOV short telephoto lens you can put on your K-3 III, I'd wager.

Okay, cockiness aside, the thing is that given that backwards compatibility is such a thing in Pentaxland, FF and APS-C models share the same K Mount (which made its debut in 1975, although it has gone through a number of iterations since then). Therefore, despite covering the FF sensor and being a bit of overkill for the smaller APS-C sensor, the DFA*50 works perfectly on your K-3 III. It will just give you a short-telephoto-equivalent field of view, instead of the wider, standard one on the FF K-1. Which is because the K-3 III only uses the center and inner borders of the image circle that the lens projects onto the sensor, but not the outer borders and corners, which are "cropped out" (scare quotes because this is not done electronically/softwarewise, as it would be on the K-1 in when set to Crop Mode, but because the APS-C sensor is simply too small to record those areas). Hope I'm making sense.

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Last edited by Madaboutpix; 01-08-2023 at 04:38 AM. Reason: Explanation added.

[Mccsiz]

Um, what do you mean "how to adapt"? You put the lens on your camera, turn on the latter, make sure that the AF switch on the lens is set to "AF", and just prepare to be amazed - it should work straight away as is. About the finest 75mm-equivalent-FOV short telephoto lens you can put on your K-3 III, I'd wager.

Okay, cockiness aside, the thing is that given that backwards compatibility is such a thing in Pentaxland, FF and APS-C models share the same K Mount (which made its debut in 1975, although it has gone through a number of iterations since then). Therefore, despite covering the FF sensor and being a bit of overkill for the smaller APS-C sensor, the DFA*50 works perfectly on your K-3 III. It will just give you a short-telephoto-equivalent field of view, instead of the wider standard one on the FF K-1. Which is because the K-3 III only uses the center and inner borders of the image circle that the lens projects onto the sensor, but not the outer borders and corners, which are "cropped out" (scare quotes because this is not done electronically/softwarewise, as it would be on the K-1 in when set to Crop Mode, but because the APS-C sensor is simply too small to record those areas). Hope I'm making sense.

Hi Madaboutpix.

After looking at full frame vs APS-C photos posted on this site, I conclude that the DFA*50 appears better suited to a full frame camera such as the K1. That being said, I have no doubt the lens will pair nicely with the K3 iii. The lens should arrive next week, so if there are certain settings that bring out the best in this lens, please share. Many bird photographers on this site were very helpful when I bought my DFA 150 - 450. Without your guidance, I would still be scratching my head about many things. I hope those who photograph people indoors have some tips as well.

Cheers,
Loyd

[Rondec]

I think the DFA *50 works better for portraits on a K-3 III than the DFA *85 does -- mainly due to the long focal length. Typically, photographers have used 85mm focal lengths (on 35mm) for portraits and the reason is that it helps you maintain a connection with your subject. The 85mm on APS-C ends up being more like the FA 135mm that I own -- albeit with better quality.

[pschlute]

I cannot show a picture taken with the DFA* 85mm on a K3II body, but it is a superb lens on FF.

I don't often use f1.4 for my doggy portraits but I did for this one.

[Mccsiz]

I cannot show a picture taken with the DFA* 85mm on a K3II body, but it is a superb lens on FF.

I don't often use f1.4 for my doggy portraits but I did for this one.

Hi Peter,

I checked out your flickr albums. You have quite an array of lenses. I noticed that you own the 77 Limited. Have you compared it to the the DFA*50?

Cheers,
Loyd

[Mccsiz]

I think the DFA *50 works better for portraits on a K-3 III than the DFA *85 does -- mainly due to the long focal length. Typically, photographers have used 85mm focal lengths (on 35mm) for portraits and the reason is that it helps you maintain a connection with your subject. The 85mm on APS-C ends up being more like the FA 135mm that I own -- albeit with better quality.

I hope you are right. I chose the 50 over the 85. It should be on my camera by tomorrow.

Cheers,
Loyd

[Mccsiz]

This was shot on the K1 with the DFA*85/1.4 at f/5 using full studio lighting.



This was shot at f/1.4, again with full studio lighting. As you can see, f/1.4 is fun, but getting the focus correct is a challenge.



I can't supply you with anything shot on the smaller format, sorry. I think the lens would be great on the K3III as a portrait lens providing you are OK with the increased working distance. The shots I have here were less than 3 meters from camera to subject. To get something similar from the K3III you would need to increase the distance to ~5 meters. I'm happy shooting portraits from that distance and the longer focal length will make backgrounds easier to manage.
The DFA* 85/1.4 is a masterclass in lens design. My opinion is that it is the best lens out there for portraiture from any manufacturer.

In respect to the girl with the cell phone, why do you think the lens focussed that way?

Cheers,
Loyd

[pschlute]

Hi Peter,

I checked out your flickr albums. You have quite an array of lenses. I noticed that you own the 77 Limited. Have you compared it to the the DFA*50?

Cheers,
Loyd

Hi Lloyd

I have not done any "test" comparisons between those lenses. I don't actually do lens tests at all, unless there is a subject to be photographed

The transition from plane of focus to OOF will be more identifiable as a "LTD style" on the 77.

I see you have ordered the DFA* 50mm 1.4. You will be astonished at how sharp that lens is across the frame at f1.4.

[Wheatfield]

In respect to the girl with the cell phone, why do you think the lens focussed that way?

Cheers,
Loyd

I hadn't done a really good job of dialing in the AF.

[sebberry]

I hope you are right. I chose the 50 over the 85. It should be on my camera by tomorrow.

Cheers,
Loyd

It's a serious lens. Shocked at how heavy it is for a 50. The lens alone feels nearly as heavy as the body + 50-135. But it's not bad for handling at all. Enjoy it!

One of the few keepers from this series. 50mm; 1/100; 1.8; ISO400; off-camera flash

[pres589]

Sandy, I totally understand what you mean by keeping a connection. But lately, I have found myself taking spontaneous photos, more like a journalist. This is why I am attracted to the 85: it is very quick to focus, but less "in your face." The 50 is ideal for intimacy, but how does it perform at a greater distance from the subject?

I think I'd be reaching for the DA 70 SMC Ltd and something wider like a 28 or 35 prime on your crop body if that's the general use case (as I think you already mentioned having at least one 50 on hand). A DA 70, one of the fast/nifty 50's, and F or FA 28 f2.8 would be a nice, compact, trio of lenses that would accomplish what you're describing. Especially with modern Pentax DSLR ISO-invariance and general image quality when asked for raised sensitivity.

[Mccsiz]

I think I'd be reaching for the DA 70 SMC Ltd and something wider like a 28 or 35 prime on your crop body if that's the general use case (as I think you already mentioned having at least one 50 on hand). A DA 70, one of the fast/nifty 50's, and F or FA 28 f2.8 would be a nice, compact, trio of lenses that would accomplish what you're describing. Especially with modern Pentax DSLR ISO-invariance and general image quality when asked for raised sensitivity.

Thanks for the input pres589.

I purchased the DFA*50, and am currently experimenting. The lens weighs a brick, making manual focus a bit more difficult than I expected.

Cheers,
Loyd

[pres589]

I hope the D-FA*50 serves you well! How much are you needing to manually focus the lens? I would think that the AF on that lens coupled with the K-3 III would mean it's rare that you would need to do so.

[Mccsiz]

Hi pres589.

My goal is to know this DFA*50 lens/K3 III camera combo so well I can switch at will. My ultimate goal is to capture intriguing images of people in the moment. This, of course, can be accomplished less conspicuously with a telephoto lens, but I'm up to the challenge. I will be satisfied when I can capture a spontaneous image that looks as good as what Medex composes in his indoor and "outdoor" studios.

As you will note after glancing at a few of my first images with this new lens, I have a long way to go

The first image in a pair is manual focus and TAv. The second in the pair is fully auto. Sorry, but I don't recall how to include EXIF.

Cheers,
Loyd

[Smolk]

I've got the DFA* 1.4/50mm and the K-3 III and it's a superb combo. It's also well-balanced, the 85mm might be a tad too heavy.

I also got the 16-50mm PLM for circumstances when I don't want to change lenses too often - when I'm walking about with others, for example, and it's excellent too, but not as fast, for wide open use I miss the DFA* 50mm.