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We should have enjoyed Aire '09 at Murcia's San Javier area this year. It's been cancelled due to . . . the recession.
Comment by Mannesty posted on Duxford Best of British Airshow 17/5/09 & 60-250mm at 19/05/2009 - 20:25
The short answer is, yes. For a manual focus lens it's only bettered by the A version which gets rid of the annoying exposure issues with M series lenses on the recent Pentax DSLR's.
Comment by Mannesty posted on 50mm lenses at 19/05/2009 - 20:22
Can you just confirm that the lettering on the lens reads 1:1.2 and not 1:2? There is a significant difference.
Comment by Mannesty posted on Shallow DOF at 19/05/2009 - 20:20
Guys, guys, the image circle produced by all lenses (AFAIK) is round, right?
All of our lenses are round, right?
I have primes that have non-rotating front elements with round (unshaped) hoods, and zooms that have tulip/petal shaped hoods.
Come to think of it, I don't think I have any primes that have rotating front elements. The only lenses I have (or remember ever having) with rotating front elements are zooms.
I have recently acquired a 500mm prime with a round hood. It has replaced a 135-600mm zoom which also had a round hood.
I think Matt's original post gave me the answer to my question. I just haven't had enough beer/wine/brandy to understand it.
Whatever, they all seem to work OK.
All of our lenses are round, right?
I have primes that have non-rotating front elements with round (unshaped) hoods, and zooms that have tulip/petal shaped hoods.
Come to think of it, I don't think I have any primes that have rotating front elements. The only lenses I have (or remember ever having) with rotating front elements are zooms.
I have recently acquired a 500mm prime with a round hood. It has replaced a 135-600mm zoom which also had a round hood.
I think Matt's original post gave me the answer to my question. I just haven't had enough beer/wine/brandy to understand it.
Whatever, they all seem to work OK.
Comment by Mannesty posted on Dumb question of the day at 19/05/2009 - 20:17
Quote:
the reciprical values your asking about are there as a rough guide to handholding a lens steady enough to avoid a blurred image, regardless of whether the subject is moving or stationary.
I agree with this, but didn't have time to add it to my post.the reciprical values your asking about are there as a rough guide to handholding a lens steady enough to avoid a blurred image, regardless of whether the subject is moving or stationary.
Quote:
even though it still a 300mm lens you have to take into account the crop facto and multuply it by 1.5
I disagree with this statement. The standard recommendation is to set the shutter speed to the reciprocal of the lens focal length, which hasn't changed just because it's on a digital body.even though it still a 300mm lens you have to take into account the crop facto and multuply it by 1.5
Comment by Mannesty posted on The law of reciprocity at 19/05/2009 - 17:42
No. A 300mm lens is still a 300mm lens whether it's fitted to a digital or film body. It's the field (or angle) of view (FOV) that changes due to the crop factor.
Your basic understanding also needs a little modification.
Shutter speed has no direct affect on image sharpness if the camera and your subject are stationary. It's the lens itself that affects sharpness, or rather, how good it is at rendering images at certain apertures.
What I think you are thinking of is the recommended minimum shutter speed for a given focal length lens to stop motion blur due to camera shake (your inability to hold the camera steady). In that case, you are right that the shutter speed should be set to the reciprocal of the lens focal length, or faster. A shutter speed of 1/300th sec or faster would suit a 300mm lens.
The shake reduction (SR) function of your camera is designed to minimise camera shake and you could set the shutter speed about 2 - 3 stops slower if it's turned on when the camera is hand held.
Your basic understanding also needs a little modification.
Shutter speed has no direct affect on image sharpness if the camera and your subject are stationary. It's the lens itself that affects sharpness, or rather, how good it is at rendering images at certain apertures.
What I think you are thinking of is the recommended minimum shutter speed for a given focal length lens to stop motion blur due to camera shake (your inability to hold the camera steady). In that case, you are right that the shutter speed should be set to the reciprocal of the lens focal length, or faster. A shutter speed of 1/300th sec or faster would suit a 300mm lens.
The shake reduction (SR) function of your camera is designed to minimise camera shake and you could set the shutter speed about 2 - 3 stops slower if it's turned on when the camera is hand held.
Comment by Mannesty posted on The law of reciprocity at 19/05/2009 - 17:26
You have two histogram displays available. The normal monochrome histogram is the Brightness histogram which shows the distribution of light (right) and dark (left) also termed luminance.
The other (hit the up key of the 4 way controller) is the RGB histogram which shows the distribution of brightness of the separate red, green, and blue channels, as well as the brightness (luminance) histogram.
The other (hit the up key of the 4 way controller) is the RGB histogram which shows the distribution of brightness of the separate red, green, and blue channels, as well as the brightness (luminance) histogram.
Comment by Mannesty posted on Image noise on K20 at 19/05/2009 - 17:16
Mike-P wrote:
Warehouse express are a lot cheaper than SRS then.
Yes Mike, £1.01 cheaper, but they won't post it for free. Warehouse express are a lot cheaper than SRS then.
Comment by Mannesty posted on Lenses prices at 19/05/2009 - 17:03
Mad dogs and englishmen go out in the pouring rain with their Pentax cameras . . . because they can.
Comment by Mannesty posted on Duxford Best of British Airshow 17/5/09 at 19/05/2009 - 16:58
Comment by Mannesty posted on Lenses prices at 19/05/2009 - 16:56
