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paperbag846 · 10-25-2010, 01:55 PM

Originally posted by troglodyte

Paperbag,
I'm trying to figure out why I'm getting the results I am. The easiest solution would be to extent the view of my A 50? Right? I only know how to take the pics, not why they turn out how they do. Dumb physics. I wish I could post some examples.

Do you post-process the raw much? Are the histograms similar between lenses? The only way to figure out why your pics turn out the way they do is to systematically change variables one by one until you see what you want to see.

**Lowell Goudge** · 10-25-2010, 03:10 PM

Originally posted by troglodyte

Lowell,
So maybe the pictures are really equally bright but are attributes of DOf, focal length and isolation fooling me?

look at the post below showing how the lens (135mm in this case) can generate "pop" with isolation of background with shallow DOF.

This post actually compared 3 identical focal length lenses at F5.6. the one on the left has an unwanted color cast and for same aperture shot at 1/2 the shutter speed as the others. The one on the right is a preset, and the middle lens is an SMC Tak/

https://www.pentaxforums.com/forums/pentax-slr-lens-discussion/99057-135mm-le...ml#post1072471

paperbag846 · 10-25-2010, 09:35 PM

Also have a look here to see the difference in aperture between different focal lengths. All of these lenses are set to f 5.6, but look at the difference in size between the apertures!

Tutorial - Focusing and DOF - #3 | Flickr - Photo Sharing!

troglodyte · 10-25-2010, 10:56 PM

I think I figured out my issue. I put my camera on a flat surface, enabled highlight compensation ( which I never do with the da21 in low light), and made my colorful bag say cheese! The Yellows and blues just pop, like the A 50mm lens. But the rest of

troglodyte · 10-25-2010, 11:01 PM

the pic looks like ass! Grrr. Maybe If I could add some sort of concentric oval gradual blur from the subject, this focal length would work.
So I think I need to save up for the Zuiko 21mm f2.

troglodyte · 10-26-2010, 12:07 AM

It looks like what I need is this program called Bokeh 2 by Alien Skin. but I really hate Photoshop CS. I love LR though.

**Digitalis** · 10-26-2010, 01:32 AM

Originally posted by troglodyte

Bokeh 2 by Alien Skin

there is no substitute for the real deal mate, you will need a faster lens. While the effect of bokeh can be imitated, it requires skill to get the effect to look natural. The difference between f/3.2 and f/2 isn't very big in terms of DOF.

paperbag846 · 10-26-2010, 07:41 AM

Originally posted by Digitalis

there is no substitute for the real deal mate, you will need a faster lens.

Don't you think that it might have more to do with the focal length? I've never seen a wide angle shot with really nice bokeh.

I reach for my 28mm when I'm working in tight spaces (or for landscapes), but the bokeh is, IMHO, rather poor. Circles of confusion render quite small and don't give me the blur I desire for a "pop".

So when I need that separation I reach for my 50mm or 55mm. The funny thing is, those extra 5 mm on the 55 make for much nicer OOF areas (i.e., large circles of confusion that begin to blur together)... which makes me think that I'm going to want something in the 70's eventually for that separation (my cheap zoom does not count

).

However if you want maximum pop with really nice rendering... check out the reviews on the 35mm 2.8 macro... all of those images really pop to me because of the amazing rendering (sharpness) and the nice bokeh rendering. Since you have a proclivity for wider angles... it might be a good compromise. Besides, you will still want to have that 21 around when compositions are tight.

The other option would be the aforementioned FA 24mm 2.0, which is said to be phenomenal by people with much deeper pockets than I.

Just a thought. Glad to hear you are figuring it out, Trog!

troglodyte · 10-26-2010, 10:41 AM

I'm going to get the demos of both PS and Bokeh 2. I'm also going to take some under exposed shots like I'm apparently doing on my A 50. I'll see if this works before spending $1,000 on converting the Zuiko.
Mathematically it's possible. They do it with

troglodyte · 10-26-2010, 10:42 AM

plenoptic lens thingy. Where everything is in focus but afterwards bokeh is added. Canon has a prototype of one looks like this bullet.

troglodyte · 10-26-2010, 11:17 PM

The DA21 has issues. Its gamma is weird. It is +19 for all but the light region which is -9. Hue for red and blue is under saturated by about +20 and +13. Also all highlight values are clipping by about +47. That's why I need to under expose! Some

troglodyte · 10-26-2010, 11:20 PM

'optimized for digital'. The A lens doesn't do this crap and is decades older with no fancy stuff. I shouldn't have to dissect images like this.

ramair455 · 10-26-2010, 11:21 PM

I have a 28 that has beautiful bokeh....

troglodyte · 10-26-2010, 11:26 PM

ramair,
It's not about the bokeh, it's the color and brightness which I figured out is a gamma issue.

summonbaka · 10-27-2010, 09:57 AM

I've just notice you've been ranting for 4 whole pages and haven't posted a single pic. Please post one of your pics that have such problem, and the 50's comparison. No tests, real photos.

10-26-2010, 10:42 AM	#55
troglodyte Veteran Member Join Date: Jul 2010 Location: Oz Posts: 408 Original Poster	plenoptic lens thingy. Where everything is in focus but afterwards bokeh is added. Canon has a prototype of one looks like this bullet. Last edited by troglodyte; 10-26-2010 at 11:43 AM.

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10-25-2010, 01:55 PM	#46
paperbag846 Veteran Member Join Date: Jul 2010 Photos: Gallery Posts: 2,395	Originally posted by troglodyte Paperbag, I'm trying to figure out why I'm getting the results I am. The easiest solution would be to extent the view of my A 50? Right? I only know how to take the pics, not why they turn out how they do. Dumb physics. I wish I could post some examples. Do you post-process the raw much? Are the histograms similar between lenses? The only way to figure out why your pics turn out the way they do is to systematically change variables one by one until you see what you want to see.

10-25-2010, 03:10 PM	#47
Lowell Goudge Site Supporter Join Date: Jan 2007 Location: Toronto Photos: Gallery \| Albums Posts: 17,892	Originally posted by troglodyte Lowell, So maybe the pictures are really equally bright but are attributes of DOf, focal length and isolation fooling me? look at the post below showing how the lens (135mm in this case) can generate "pop" with isolation of background with shallow DOF. This post actually compared 3 identical focal length lenses at F5.6. the one on the left has an unwanted color cast and for same aperture shot at 1/2 the shutter speed as the others. The one on the right is a preset, and the middle lens is an SMC Tak/ https://www.pentaxforums.com/forums/pentax-slr-lens-discussion/99057-135mm-le...ml#post1072471

10-25-2010, 09:35 PM	#48
paperbag846 Veteran Member Join Date: Jul 2010 Photos: Gallery Posts: 2,395	Also have a look here to see the difference in aperture between different focal lengths. All of these lenses are set to f 5.6, but look at the difference in size between the apertures! Tutorial - Focusing and DOF - #3 \| Flickr - Photo Sharing!

10-25-2010, 10:56 PM	#49
troglodyte Veteran Member Join Date: Jul 2010 Location: Oz Posts: 408 Original Poster	I think I figured out my issue. I put my camera on a flat surface, enabled highlight compensation ( which I never do with the da21 in low light), and made my colorful bag say cheese! The Yellows and blues just pop, like the A 50mm lens. But the rest of

10-25-2010, 11:01 PM	#50
troglodyte Veteran Member Join Date: Jul 2010 Location: Oz Posts: 408 Original Poster	the pic looks like ass! Grrr. Maybe If I could add some sort of concentric oval gradual blur from the subject, this focal length would work. So I think I need to save up for the Zuiko 21mm f2.

10-26-2010, 12:07 AM	#51
troglodyte Veteran Member Join Date: Jul 2010 Location: Oz Posts: 408 Original Poster	It looks like what I need is this program called Bokeh 2 by Alien Skin. but I really hate Photoshop CS. I love LR though.

10-26-2010, 01:32 AM	#52
Digitalis Site Supporter Join Date: Mar 2009 Location: Melbourne, Victoria Photos: Gallery Posts: 11,695	Originally posted by troglodyte Bokeh 2 by Alien Skin there is no substitute for the real deal mate, you will need a faster lens. While the effect of bokeh can be imitated, it requires skill to get the effect to look natural. The difference between f/3.2 and f/2 isn't very big in terms of DOF.

10-26-2010, 07:41 AM	#53
paperbag846 Veteran Member Join Date: Jul 2010 Photos: Gallery Posts: 2,395	Originally posted by Digitalis there is no substitute for the real deal mate, you will need a faster lens. Don't you think that it might have more to do with the focal length? I've never seen a wide angle shot with really nice bokeh. I reach for my 28mm when I'm working in tight spaces (or for landscapes), but the bokeh is, IMHO, rather poor. Circles of confusion render quite small and don't give me the blur I desire for a "pop". So when I need that separation I reach for my 50mm or 55mm. The funny thing is, those extra 5 mm on the 55 make for much nicer OOF areas (i.e., large circles of confusion that begin to blur together)... which makes me think that I'm going to want something in the 70's eventually for that separation (my cheap zoom does not count ). However if you want maximum pop with really nice rendering... check out the reviews on the 35mm 2.8 macro... all of those images really pop to me because of the amazing rendering (sharpness) and the nice bokeh rendering. Since you have a proclivity for wider angles... it might be a good compromise. Besides, you will still want to have that 21 around when compositions are tight. The other option would be the aforementioned FA 24mm 2.0, which is said to be phenomenal by people with much deeper pockets than I. Just a thought. Glad to hear you are figuring it out, Trog!

10-26-2010, 10:41 AM	#54
troglodyte Veteran Member Join Date: Jul 2010 Location: Oz Posts: 408 Original Poster	I'm going to get the demos of both PS and Bokeh 2. I'm also going to take some under exposed shots like I'm apparently doing on my A 50. I'll see if this works before spending $1,000 on converting the Zuiko. Mathematically it's possible. They do it with

10-26-2010, 11:17 PM	#56
troglodyte Veteran Member Join Date: Jul 2010 Location: Oz Posts: 408 Original Poster	The DA21 has issues. Its gamma is weird. It is +19 for all but the light region which is -9. Hue for red and blue is under saturated by about +20 and +13. Also all highlight values are clipping by about +47. That's why I need to under expose! Some

10-26-2010, 11:20 PM	#57
troglodyte Veteran Member Join Date: Jul 2010 Location: Oz Posts: 408 Original Poster	'optimized for digital'. The A lens doesn't do this crap and is decades older with no fancy stuff. I shouldn't have to dissect images like this.

10-26-2010, 11:21 PM	#58
ramair455 Senior Member Join Date: Sep 2009 Location: Okc Photos: Gallery Posts: 284	I have a 28 that has beautiful bokeh....

10-26-2010, 11:26 PM	#59
troglodyte Veteran Member Join Date: Jul 2010 Location: Oz Posts: 408 Original Poster	ramair, It's not about the bokeh, it's the color and brightness which I figured out is a gamma issue.

10-27-2010, 09:57 AM	#60
summonbaka Senior Member Join Date: Dec 2009 Location: Kagoshima, Japan Photos: Gallery \| Albums Posts: 237	I've just notice you've been ranting for 4 whole pages and haven't posted a single pic. Please post one of your pics that have such problem, and the 50's comparison. No tests, real photos.

Is the 50mm A1.7 faster than F1.7?

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