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05-01-2014, 02:31 PM   #1
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Rendering vs sharpness

I got a similar, very non-scientific comparison between two of my favorite lenses, the A 70-210mm f4 and the DA 35mm 2.4. They both focus close, but the 35mm was cropped quite a bit to give it a similar type of composition. Then I tried to get them close in terms of sharpness. That meant the prime was shot wide open and the A at f/8! But I think the DOF was still enough to keep the petals in focus. And the center of the flower is still way sharper with the 35, even after the cropping. But that might be due to a bit of motion blur in the A 70-210 shot - taking a pic at 70mm f/8 is quite different from 35mm at f/2.4...

I'm not saying one lens is better than the other. Both can render beautifully in my opinion. But I do find it interesting how, with very similar same PP applied, they still look quite a bit different. For flowers, the old A 70-210 is my favorite lens because the pictures always seem to have that extra niceness to them - as long as there's enough light...

So here's the DA 35



And the A 70-210 at 70mm:



Do you guys think the difference is because of the DOF? I might have to try both at f/8 to see what the difference is... also, one picture had sun, the other didn't. Usually though, in these kinds of pictures, the sun turns out to be a disadvantage...

So, how much importance do you give to rendering and how does it affect what lenses you use for what jobs?

05-01-2014, 02:43 PM - 1 Like   #2
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Well multiple things here...

1) The saturation is too damn high! In that, the DA 35 shot is actually more saturated (either by exposure, or by processing) than the 70-210 shot. That makes it hard to judge rendering.
2) The motion blur really doesn't help.
3) Shooting wide open on the DA 35 gives it lovely blurred bokeh. Shooting at F8 on the 70-210 makes the bokeh look cruddy.
4) The colors don't really match up - not sure if that's because of processing or lens. The greens in the DA 35 shot are softer and prettier. The greens in the 70-210 shot are warmer and uglier.

Not to be too harsh, but these two shots have just too much difference to make a reasonable attempt to compare rendering.
05-01-2014, 02:47 PM   #3
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I think the bright light (and the sharp shadows that come with it) in the second shot makes most of the difference. I bought a gently used A 70-210 f/4 ten years ago, and it was my favorite lens on my film cameras, and still gets lots of use with my K-30. Something about it seems to make the background brighter than with my other lenses and the in focus zone seems curvier. Hardly a scientific observation though, and I don't have the DA 35, so I can't offer much regarding it.

---------- Post added 05-01-14 at 03:51 PM ----------

QuoteOriginally posted by JinDesu Quote
The greens in the DA 35 shot are softer and prettier.
Depends on your audience. Especially in a glossy print, most people will prefer the warmer greens and find the higher contrast in the red petals more attractive.
05-01-2014, 02:51 PM   #4
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I think DOF is your primary problem. Use a DOF calcuator on your smartphone or online.

These generations of lenses will always render a bit differently from each other. A and F lenses, in particular, have nice glass IMO.


But I'd expect a good shot from either lens, if both are used properly.

05-01-2014, 02:57 PM   #5
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I didn't increase saturation in either picture, just tweaked the contrast curve a little bit - and copied one setting to the other, so the PP should be identical as far as the color handling is concerned. The DA 35 indeed has more contrast SOOC. But the changes I made did to the contrast curve did increase the saturation a bit, I'm sure - to both pictures equally.
The DOF is much narrower in the DA 35, but it's enough to get most of the rose in focus I think. That bud on the top is my reference for that.
I know this isn't a scientific comparison by any means, I'm just a bit surprised at how differently those lenses deal with the colors. Like I said, I probably should redo this with both at f8 (or maybe f4), even though the sharpness difference will make the shots even more apples to oranges.
Again, this isn't to say one lens is better than the other. Technically, the DA is the better lens by far, I think.
05-01-2014, 02:58 PM   #6
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Just my opinion, the DOF on the DA35 shot is so shallow that you lose the 3-D effect entirely. With the second shot, the image transitions more smoothly from the in-focus to the out-of-focus areas.
05-01-2014, 03:58 PM   #7
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Um ... define rendering for me please, I'm not sure what you mean by it?

Oh and sharpness really should be qualified to a more accurate term: resolution? acutance?
05-01-2014, 04:25 PM   #8
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So, you took two totally different pictures under totally different lighting conditions at totally different apertures, with different lenses... In that case the only thing you can compare is the colour rendition , and that is a matter of personal preference anyway.

I prefer the greens from the 35, and red is very difficult to get right it seems, it often over saturates. The 70-210 doesn't give a perfect red either, IMO.

But LBA rules, I would like to have both lenses in my collection!

05-02-2014, 05:58 AM   #9
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QuoteOriginally posted by Bagga_Txips Quote
So, you took two totally different pictures under totally different lighting conditions at totally different apertures, with different lenses... In that case the only thing you can compare is the colour rendition , and that is a matter of personal preference anyway.

I prefer the greens from the 35, and red is very difficult to get right it seems, it often over saturates. The 70-210 doesn't give a perfect red either, IMO.
You forgot to say different focal lengths Yes, that was the point - from my understanding rendering usually means how the colors are represented. So that is the only thing I was looking at. And red is, I think, the most difficult color in digital photography. Yellow is hard too. I find that usually my older lenses deal better with these colors, but then I have older glass that was good glass when it came out, and my new glass is all budget glass. I'd say if I had a DA 35 2.8 Limited Macro (or any other Limited, really) the story would be totally different! Then sharpness AND rendering would both come together in one package.

I do like the red and green better with the A 70-210 (despite the pic losing so badly in sharpness), but as I'm finding out, that's just my preference. And as I said, there's no "better", there's just what each person prefers.

Anyway, sorry if this is just musings and maybe thinking out loud. But perhaps I'm providing some people a break from the deluge of "which lens should I get" threads.
05-02-2014, 07:09 AM   #10
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I do like the 35mm photo better. Depth of field is more narrow on it, bokeh is nicer. Reds are kind of blown out in both, which I think is what leads to the perception of lack of sharpness.

I do think macro lenses, tend to be a notch above just because they are sharp and just render out of focus areas really smoothly.
05-02-2014, 07:21 AM   #11
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It seems most lenses blow out the reds even SOOC. Looking at the unprocessed pictures they're not much better than what's above (and I shoot raw).
My Tamron 70-300 LD DI is even worse. It blows out the colors like crazy. My 18-55 AL II even seems to blow out greens sometimes. That's why I was saying, this might be a "feature" of budget lenses.
05-02-2014, 07:32 AM   #12
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yes, you may notice more detail on the petals when you lower the red saturation a bit.
05-02-2014, 07:37 AM   #13
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QuoteOriginally posted by ChristianRock Quote
It seems most lenses blow out the reds even SOOC. Looking at the unprocessed pictures they're not much better than what's above (and I shoot raw).
My Tamron 70-300 LD DI is even worse. It blows out the colors like crazy. My 18-55 AL II even seems to blow out greens sometimes. That's why I was saying, this might be a "feature" of budget lenses.
I think Mike is right. If you pull down exposure, I think you will find there is more detail. This is a shot of a (red) cardinal and the initial shot looked lousy. I pulled down the exposure by 1EV and suddenly the cardinal's red looked OK, as was the detail.

05-02-2014, 07:38 AM   #14
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The quality of the light has an even greater impact on the final image than the rendering of the lens. Therefore the fact that the quality of light is better in the DA 35 shot than in the A 70-210 shot makes it very hard to make meaningful comparisons. Moreover, it looks to me that the red channel was blown in both shots, as I'm not seeing much detail in the petals.

Prima facie, I would expect the DA 35 to have better color rendition than the A 70-210 because it has less glass and uses better, more modern anti-reflective coatings.
05-02-2014, 07:40 AM   #15
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The saturation in the DA35 shot makes my eyes hurt.
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