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10-28-2010, 09:55 AM - 1 Like   #76
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QuoteOriginally posted by paperbag846 Quote
While I'm still not sure what is bothering him so much, I still think that he is noticing the benefit of a longer focal length w.r.t subject/background seperation, which is much more challenging to do with a wide angle lens.
I agree. He just prefers shooting with a short telephoto. Not sure why he needs to rant about it....


"Ughhhhhhhhh, I hate hot dogs. I prefer hamburgers...Why can't they make a hot dog taste like a hamburger? I was measuing the length of the hot dog, and it's too long....They should be flat and patty-like"

"Uh, just go and order a hamburger?"

10-28-2010, 10:45 AM   #77
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QuoteOriginally posted by egordon99 Quote
But they SHOULD be close. Otherwise external (incident) light meters would NOT work.

Using the f/ notation takes the focal length out of the "equation". Otherwise you would just use absolute aperture. "Yeah, I'm shooting my 50mm at an aperture of 25mm. To retain my exposure with my 30mm, I'll need to shoot at an aperture of 15mm."

Using f/2 makes much more sense when talking about aperture in regards to exposure.
Oh, thank you so much for clearing this one up for me!

So, as an aside, a 35mm 2.4 lens should gather more light than a 40mm 2.8?
10-28-2010, 10:52 AM   #78
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QuoteOriginally posted by paperbag846 Quote
Oh, thank you so much for clearing this one up for me!

So, as an aside, a 35mm 2.4 lens should gather more light than a 40mm 2.8?
In theory, yes. Because f/2.4 is brighter than f/2.8.

A 50mm f/1.4 is brighter than a 400mm f/2.8, even though the 400mm f/2.8's front element is much bigger.
10-28-2010, 12:14 PM   #79
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I got this confused because I have a 50mm 1.7 and a 55mm 1.8.

The 55 1.8 lets in between 1/2 and 1 more stop of light in. But I suppose that is where you get into optical design, number & thickness of elements, etc.

10-29-2010, 01:38 AM   #80
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gordon,
I made some more presets so now all I have to do is a few clicks and the images look a lot better. I don't know why but the da21 seems to be rendering duller images. The only way to fix that is to under expose by about 1.3 stops and then shift
10-29-2010, 01:44 AM   #81
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things. Other wise, certain details in highlights get clipped. Also the images can tend to look too smooth from bad focus.
Oh, btw I actually like wide angles better than moderate telephoto lenses. I just like taking tight frame pics. Depending on how far
10-29-2010, 01:49 AM   #82
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away will determine the lens. I'm actually liking my da21 in semi low light now. Now that I have the Trog-TM presets. They were a bitch to make. Now I just wish Pentax had a FF so I could get the FA31 and have a f1.8 with the same fov as the da21 on aps-c
10-29-2010, 05:52 AM   #83
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QuoteOriginally posted by troglodyte Quote
Now I just wish Pentax had a FF so I could get the FA31 and have a f1.8 with the same fov as the da21 on aps-c
Considering you just mentioned that you had trouble focusing with a f3.2 lens, I doubt f1.8 would go much better.

You are trying to do something pretty hard, so I'm not surprised that it's taking a while. Wide angles are not that easy to focus when you get really close to your subject. However, if you do, it can make for a really cool effect.

Also clipped highlights can easily ruin a picture, but have nothing to do with the lens. When you slap a wide angle on your camera, all of the metering "spreads out". You might want to consider spot metering your subject to avoid, say, blowing the highlights in a candle. You will need to make use of ev compensation too.

Give it a shot .

10-29-2010, 06:04 AM   #84
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QuoteOriginally posted by paperbag846 Quote
Wide angles are not that easy to focus when you get really close to your subject. .
I have no problems focusing with my Sigma 10-20mm (even at 10mm) on close objects. Obviously you have to be within the MFD of the lens.

What kind of problems are you having?
10-29-2010, 06:06 AM   #85
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QuoteOriginally posted by troglodyte Quote
away will determine the lens. I'm actually liking my da21 in semi low light now. Now that I have the Trog-TM presets. They were a bitch to make. Now I just wish Pentax had a FF so I could get the FA31 and have a f1.8 with the same fov as the da21 on aps-c
Sigma makes a 20mm f/1.8 I believe. Might be worth looking into.
10-29-2010, 06:14 AM   #86
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QuoteOriginally posted by egordon99 Quote
I have no problems focusing with my Sigma 10-20mm (even at 10mm) on close objects. Obviously you have to be within the MFD of the lens.

What kind of problems are you having?
I don't have any problems anymore, it's simply a matter of nailing focus. My eyes have been trained. I suspect it's HARDER for him to manually focus the 21mm over the 50mm.

Personal experience: nailing focus on a 28 2.8 vs 55 1.8 - 55 1.8 always easier (for me).
10-29-2010, 06:21 AM   #87
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QuoteOriginally posted by paperbag846 Quote
I don't have any problems anymore, it's simply a matter of nailing focus. My eyes have been trained. I suspect it's HARDER for him to manually focus the 21mm over the 50mm.

Personal experience: nailing focus on a 28 2.8 vs 55 1.8 - 55 1.8 always easier (for me).
Oops, I forgot you're talking about MANUAL focus....

I had the SMC-A 50mm f/1.7 and I loved the lens, I just hated having to focus it myself. Maybe if I had a proper focusing screen.
10-29-2010, 06:26 AM   #88
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QuoteOriginally posted by egordon99 Quote
Oops, I forgot you're talking about MANUAL focus....

I had the SMC-A 50mm f/1.7 and I loved the lens, I just hated having to focus it myself. Maybe if I had a proper focusing screen.
You do get used to it... you look for the "pop" and snap the shot. The pop is less obvious in wide angle situations. That said, I'm now looking for some af because I'm tired of missing shots .

Last edited by paperbag846; 10-29-2010 at 08:45 AM.
10-29-2010, 11:01 AM   #89
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Paperbag,
I can always stopdown? A FF has a bigger focusing area so it's easier to focus faster f-stops? Lastly, a faster lens behaves way better at f3.2 than a lens that starts at f3.2? But I'd still like to try that f2 21mm zuiko. I think 99% of my
10-29-2010, 11:05 AM   #90
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problem was not getting PP right, the other 1% was exposure. You know how if you darken an image colors look richer? The A50 can do that and blur out the bad parts. I can do the same with the da21 if I PP properly changing gamma, colors and sharpening.
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