Which Focal Length For Portraits...And Why?

carpents · 02-13-2007, 05:55 PM

This all got me to thinking, so I pulled out 9 different lenses. I set up the tripod and a chair and pulled the setup progressively further apart as the focal length increased. This is a reduced version of what I ended up with:

(A much bigger version is here.)

My, what a big head I have at 24mm! Comments welcome, although not on the model!

[The lenses I used were, from left to right: S-M-C Takumar 24/3.5, S-M-C Takumar 28/3.5, 31mm Limited, A50/1.2, 77mm Limited, Super-Takumar 85/1.9, DFA100/2.8 Macro, S-M-C Takumar 135/2.5. All of them were either at f/2.8 or f/4 - I just picked the best focused one. Levels applied to all of them.]

Rolly · 02-13-2007, 09:57 PM

Just a brief comment on the sharpness issue: if the product from the lens and camera is critically sharp then all the image information is present for adjustment in PP as required for the final image. Further adjustments can be made to meet other needs on an 'as required' basis. However, this is not possible with a deliberately shot 'soft image'. It's one of the great boons of having a "digital darkroom".

kjao · 02-14-2007, 05:25 AM

Hi egordon99

Originally posted by egordon99

I'd love to hear people's experience with this. Like I said, I think a 100mm f/2.8 prime would be great! In Pentax land, that means one of the macro lenses.

Sean - You have the DFA 100mm, right? How is the autofocus on that? Especially in indoor lighting?

Just FYI, Pentax has got a M100/2.8 lens that's NOT macro and manual focus of course since it is an M lens. Here is the link to Bojidar's page:
M 100/2.8

Hope that helps,

cheers
Kenny

carpents · 02-14-2007, 06:16 AM

Originally posted by awjweb

I like to use a FA 50mm 1.4 usually at 4.0 for sharpness and so that DOF is not so paper thin. (pics link to fullsize images)

Shot at f2.0:

Tony

This is simultaneously adorable and really scary!

carpents · 02-14-2007, 06:18 AM

Originally posted by kjao

Hi egordon99

Just FYI, Pentax has got a M100/2.8 lens that's NOT macro and manual focus of course since it is an M lens. Here is the link to Bojidar's page:
M 100/2.8

Hope that helps,

cheers
Kenny

There is an A version of the 100/2.8 Macro, too. I'd rather have the A version using a Pentax DSLR.

carpents · 02-14-2007, 06:20 AM

Originally posted by Rolly

Just a brief comment on the sharpness issue: if the product from the lens and camera is critically sharp then all the image information is present for adjustment in PP as required for the final image. Further adjustments can be made to meet other needs on an 'as required' basis. However, this is not possible with a deliberately shot 'soft image'. It's one of the great boons of having a "digital darkroom".

I'd be interested in seeing some samples of this. I have a hard time blending in a Gaussian blur naturally.

carpents · 02-14-2007, 06:20 AM

Originally posted by betsypdx

Good question. I've done everything from 10 - 400, it all depends where I am and what I'm doing. I probably use the 50mm and the 77mm the most. (and, you'll notice that I also tend to get in close with my portraits - it's good to see that others do too since a friend after looking at my pics was asking why I always "cut off" the top of people's heads)

at 10mm

at 77mm

at 138mm

at 400mm

That 10mm shot of Max is killer.

carpents · 02-14-2007, 06:21 AM

Ivan, those are great shots.

Zubati Kit · 02-14-2007, 08:29 AM

I think picture #6 is the best, but it might be the light...

I guess it depends what do you want to do with the picture, this comparison shows some distortion at wide angle, while the tele end is similar in reproduction... perhaps slightly flatter, but not much to chose between them... so #6 out of them... but it might only be that I prefer the stronger light more than anything else, I am not that sharp on perspective distortion to be able to have a clear preference out of the tele lenses in this example on the top.

carpents · 02-14-2007, 08:39 AM

Originally posted by Zubati Kit

I think picture #6 is the best, but it might be the light...

I guess it depends what do you want to do with the picture, this comparison shows some distortion at wide angle, while the tele end is similar in reproduction... perhaps slightly flatter, but not much to chose between them... so #6 out of them... but it might only be that I prefer the stronger light more than anything else, I am not that sharp on perspective distortion to be able to have a clear preference out of the tele lenses in this example on the top.

Yeah, I have to say that I think (as far as perspective/reproduction goes) numbers 4-7 (35mm, 50mm, 77mm, 85mm) look good to me. The others don't look bad, especially 8 and 9, but the middle ones look more 'natural'.

One important note which certainly makes a difference in the focal length you choose - the 24mm portrait was taken from approximately 2 feet away, whereas the 135mm portrait was from about 12 feet. So if I'm taking shots in an intimate environment, I would probably say the 35mm is my best bet. If I wanted more space between myself and the model, it looks like an 85mm or even 100mm would work fine.

I'm glad I did this. I had no idea, plus it was really fun to take self portraits with 9 different lenses! I was laughing the whole time.

Zubati Kit · 02-14-2007, 09:13 AM

yes, a good test and reference

distance is certainly interesting, to me it would be more whether you are inside or outside... I mostly used 28mm tak so far, which seems a bit weak for portraits here, showing more of the distortion in comparison... but I was quite happy so far, and really I think that if you get a bit further away this distortion is smaller too, but than this is not a real portrait shot anymore...

02-13-2007, 05:55 PM	#16
carpents Veteran Member Join Date: Sep 2006 Location: West Chester, PA Photos: Gallery \| Albums Posts: 1,420 Original Poster	Okay, So I Did An Experiment... This all got me to thinking, so I pulled out 9 different lenses. I set up the tripod and a chair and pulled the setup progressively further apart as the focal length increased. This is a reduced version of what I ended up with: (A much bigger version is here.) My, what a big head I have at 24mm! Comments welcome, although not on the model! [The lenses I used were, from left to right: S-M-C Takumar 24/3.5, S-M-C Takumar 28/3.5, 31mm Limited, A50/1.2, 77mm Limited, Super-Takumar 85/1.9, DFA100/2.8 Macro, S-M-C Takumar 135/2.5. All of them were either at f/2.8 or f/4 - I just picked the best focused one. Levels applied to all of them.]

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02-13-2007, 09:57 PM	#17
Rolly Senior Member Join Date: Oct 2006 Location: Perth, Western Australia Posts: 295	Just a brief comment on the sharpness issue: if the product from the lens and camera is critically sharp then all the image information is present for adjustment in PP as required for the final image. Further adjustments can be made to meet other needs on an 'as required' basis. However, this is not possible with a deliberately shot 'soft image'. It's one of the great boons of having a "digital darkroom".

02-14-2007, 05:25 AM	#18
kjao Veteran Member Join Date: Sep 2006 Location: Melbourne, Australia Posts: 423	Hi egordon99 Originally posted by egordon99 I'd love to hear people's experience with this. Like I said, I think a 100mm f/2.8 prime would be great! In Pentax land, that means one of the macro lenses. Sean - You have the DFA 100mm, right? How is the autofocus on that? Especially in indoor lighting? Just FYI, Pentax has got a M100/2.8 lens that's NOT macro and manual focus of course since it is an M lens. Here is the link to Bojidar's page: M 100/2.8 Hope that helps, cheers Kenny

02-14-2007, 06:16 AM	#19
carpents Veteran Member Join Date: Sep 2006 Location: West Chester, PA Photos: Gallery \| Albums Posts: 1,420 Original Poster	Originally posted by awjweb I like to use a FA 50mm 1.4 usually at 4.0 for sharpness and so that DOF is not so paper thin. (pics link to fullsize images) Shot at f2.0: Tony This is simultaneously adorable and really scary!

02-14-2007, 06:18 AM	#20
carpents Veteran Member Join Date: Sep 2006 Location: West Chester, PA Photos: Gallery \| Albums Posts: 1,420 Original Poster	Originally posted by kjao Hi egordon99 Just FYI, Pentax has got a M100/2.8 lens that's NOT macro and manual focus of course since it is an M lens. Here is the link to Bojidar's page: M 100/2.8 Hope that helps, cheers Kenny There is an A version of the 100/2.8 Macro, too. I'd rather have the A version using a Pentax DSLR.

02-14-2007, 06:20 AM	#21
carpents Veteran Member Join Date: Sep 2006 Location: West Chester, PA Photos: Gallery \| Albums Posts: 1,420 Original Poster	Originally posted by Rolly Just a brief comment on the sharpness issue: if the product from the lens and camera is critically sharp then all the image information is present for adjustment in PP as required for the final image. Further adjustments can be made to meet other needs on an 'as required' basis. However, this is not possible with a deliberately shot 'soft image'. It's one of the great boons of having a "digital darkroom". I'd be interested in seeing some samples of this. I have a hard time blending in a Gaussian blur naturally.

02-14-2007, 06:20 AM	#22
carpents Veteran Member Join Date: Sep 2006 Location: West Chester, PA Photos: Gallery \| Albums Posts: 1,420 Original Poster	Originally posted by betsypdx Good question. I've done everything from 10 - 400, it all depends where I am and what I'm doing. I probably use the 50mm and the 77mm the most. (and, you'll notice that I also tend to get in close with my portraits - it's good to see that others do too since a friend after looking at my pics was asking why I always "cut off" the top of people's heads) at 10mm at 77mm at 138mm at 400mm That 10mm shot of Max is killer.

02-14-2007, 06:21 AM	#23
carpents Veteran Member Join Date: Sep 2006 Location: West Chester, PA Photos: Gallery \| Albums Posts: 1,420 Original Poster	Ivan, those are great shots.

02-14-2007, 08:29 AM	#24
Zubati Kit Senior Member Join Date: Feb 2007 Location: UK Posts: 113	I think picture #6 is the best, but it might be the light... I guess it depends what do you want to do with the picture, this comparison shows some distortion at wide angle, while the tele end is similar in reproduction... perhaps slightly flatter, but not much to chose between them... so #6 out of them... but it might only be that I prefer the stronger light more than anything else, I am not that sharp on perspective distortion to be able to have a clear preference out of the tele lenses in this example on the top.

02-14-2007, 08:39 AM	#25
carpents Veteran Member Join Date: Sep 2006 Location: West Chester, PA Photos: Gallery \| Albums Posts: 1,420 Original Poster	Originally posted by Zubati Kit I think picture #6 is the best, but it might be the light... I guess it depends what do you want to do with the picture, this comparison shows some distortion at wide angle, while the tele end is similar in reproduction... perhaps slightly flatter, but not much to chose between them... so #6 out of them... but it might only be that I prefer the stronger light more than anything else, I am not that sharp on perspective distortion to be able to have a clear preference out of the tele lenses in this example on the top. Yeah, I have to say that I think (as far as perspective/reproduction goes) numbers 4-7 (35mm, 50mm, 77mm, 85mm) look good to me. The others don't look bad, especially 8 and 9, but the middle ones look more 'natural'. One important note which certainly makes a difference in the focal length you choose - the 24mm portrait was taken from approximately 2 feet away, whereas the 135mm portrait was from about 12 feet. So if I'm taking shots in an intimate environment, I would probably say the 35mm is my best bet. If I wanted more space between myself and the model, it looks like an 85mm or even 100mm would work fine. I'm glad I did this. I had no idea, plus it was really fun to take self portraits with 9 different lenses! I was laughing the whole time.

02-14-2007, 09:13 AM	#26
Zubati Kit Senior Member Join Date: Feb 2007 Location: UK Posts: 113	yes, a good test and reference distance is certainly interesting, to me it would be more whether you are inside or outside... I mostly used 28mm tak so far, which seems a bit weak for portraits here, showing more of the distortion in comparison... but I was quite happy so far, and really I think that if you get a bit further away this distortion is smaller too, but than this is not a real portrait shot anymore...