All Forum Comments
Comment by K10D posted on Sigma reducing prices. at 23/01/2010 - 11:19
First two are obviously off track, if milliseconds count, I would not be using my K7. The third advert suggests something different, pity about the spelling mistake (seductiely).
As for the K7 advert, are Pentax users only classed as hobbyists?
Time to find a sense of direction...
Regards
As for the K7 advert, are Pentax users only classed as hobbyists?
Time to find a sense of direction...
Regards
Comment by K10D posted on Pentax adverts at 23/01/2010 - 11:17
Comment by K10D posted on Sigma Lenses reduced? at 21/01/2010 - 17:58
Not a Trekpod but a Trailwise Photo Shoot T85P. A three section "twist to lock" stick. Very useful with a 234RC head fitted.
link
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link
Regards
Comment by K10D posted on Anyone got a Trekpod? at 21/01/2010 - 15:31
Welcome back.
Regards
Regards
Comment by K10D posted on Hi All..... at 19/01/2010 - 17:01
Anvh wrote:
FOV doesn't change with distance. The angle is constant. Opposite distance "width" increases with distance.
No you got that wrong.K10D wrote:
If you want you can have the same field of view with a 50mm lens on an APS-C sensor compared to an MF.
FOV increase with distance so that's why you can have the same FOV.
Am I correct or do I mess it up now?
FOV is fixed per lens focal length as per image area coverage of sensor.Anvh wrote:
[quote:3496ace15f="K10D"]The 50 mm only has the field of view of a lens 1.5 times longer focal length. However, the cropped sensor sees no more magnification with a 50mm lens tahn a FF sensor.
Regards
Sorry to go off topic here but is it not better to use angel of view instead of field of view?[quote:3496ace15f="K10D"]The 50 mm only has the field of view of a lens 1.5 times longer focal length. However, the cropped sensor sees no more magnification with a 50mm lens tahn a FF sensor.
Regards
If you want you can have the same field of view with a 50mm lens on an APS-C sensor compared to an MF.
FOV increase with distance so that's why you can have the same FOV.
Am I correct or do I mess it up now?
FOV doesn't change with distance. The angle is constant. Opposite distance "width" increases with distance.
AOV (angle of view) has a fixed angle and is fixed per lens relative to the sensor size, look up a lens specification, it says AOV.
And yes FOV change with distance since it's in the formula:
f is the film distance (focal length can be used most of the times)
d is the object distance
o is the object dimension
i is the image dimension[/quote]I stand corrected Stefan, I should have typed AOV, hence I typed "width" (FOV) increases with distance.
Regards
Comment by K10D posted on Best portrait lens at 19/01/2010 - 07:20
Anvh wrote:
If you want you can have the same field of view with a 50mm lens on an APS-C sensor compared to an MF.
FOV increase with distance so that's why you can have the same FOV.
Am I correct or do I mess it up now?
FOV is fixed per lens focal length as per image area coverage of sensor.K10D wrote:
The 50 mm only has the field of view of a lens 1.5 times longer focal length. However, the cropped sensor sees no more magnification with a 50mm lens tahn a FF sensor.
Regards
Sorry to go off topic here but is it not better to use angel of view instead of field of view?The 50 mm only has the field of view of a lens 1.5 times longer focal length. However, the cropped sensor sees no more magnification with a 50mm lens tahn a FF sensor.
Regards
If you want you can have the same field of view with a 50mm lens on an APS-C sensor compared to an MF.
FOV increase with distance so that's why you can have the same FOV.
Am I correct or do I mess it up now?
A 50mm lens is rated at approx 1x magnification on a FF sensor. On a croped sensor it is 1/1.5 or .666. The focal length of a lens on a SLR/DSLR body does not change, we just see less area or .666 of a FF image.
FOV doesn't change with distance. The angle is constant. Opposite distance "width" increases with distance.
The magnification of a 100mm lens is approx 2x on a FF sensor and remains so on a cropped sensor. Moving back 1.5 times the distance from camera to subject is the same image as a FF but is still .666 of the size.
Regards
Comment by K10D posted on Best portrait lens at 18/01/2010 - 22:02
Mike-P wrote:
Let's face it, all camera makes have their own good and bad points and most users will defend theirs to the death.
So do I, Nail it with a Nikon, Catch it with a Canon, Manage with Minolta or be Savy with a Sony?Let's face it, all camera makes have their own good and bad points and most users will defend theirs to the death.
Regards
Comment by K10D posted on K7 Review at The Register at 18/01/2010 - 19:26
johnnyboy114 wrote:
Hi
I have a K100D, with an old manual 50mm f1.7, a Sigma 70-300 f4.5 and the kit lens and was wondering, what was the best portrait lens to use? I am thinking the 50mm as its more equivalent to 85mm and that its also a lot faster for a nicer DOF, but I really like the look of a telephoto lens for portraiture but not sure that the Sigma is up to the job, especially with the slower speed....
I am likely to be using the 50mm I guess, but I have a problem focusing it in the darker light most of my portraits will be taken in as I am useless at manual focusing without a split circle on the mirror! lol! Any tips on this? Or, is there a CHEAP alternative that might be worth considering for portraiture?
Any help and advice on this would be great. Thanks!
John
The 50 mm only has the field of view of a lens 1.5 times longer focal length. However, the cropped sensor sees no more magnification with a 50mm lens tahn a FF sensor. Hi
I have a K100D, with an old manual 50mm f1.7, a Sigma 70-300 f4.5 and the kit lens and was wondering, what was the best portrait lens to use? I am thinking the 50mm as its more equivalent to 85mm and that its also a lot faster for a nicer DOF, but I really like the look of a telephoto lens for portraiture but not sure that the Sigma is up to the job, especially with the slower speed....
I am likely to be using the 50mm I guess, but I have a problem focusing it in the darker light most of my portraits will be taken in as I am useless at manual focusing without a split circle on the mirror! lol! Any tips on this? Or, is there a CHEAP alternative that might be worth considering for portraiture?
Any help and advice on this would be great. Thanks!
John
Regards
Comment by K10D posted on Best portrait lens at 18/01/2010 - 19:19
Out and about with the 50-135.
I am very happy with it.
Regards
I am very happy with it.
Regards
Comment by K10D posted on 50-135 results at 17/01/2010 - 21:24
Oh yes, just found it.
Silly me for posting it in the lens section when obviously I should have looked in the general first
Now if only they did that 120-300mm f2.8 in Pentax mount.
Regards