Search results for 'sensor cleaning' - page 85
SMC DA 10-17mm fish eye announced
Here's an interesting question with regard to this lens... The fish-eye 10-17mm is quoted as having "180 degree" angle of view on an *ist-D The 12-24mm is quoted as "99 degree" angle of view (at 12mm) Now, the angle of view = 2 * arctan (28.26/ (f * 2)) Where f is the focal length in mm, An...
Posted by MattMatic on 18/01/2006 - 12:22
77mm Limited, 85mm F1.4 OR 100mm Macro 2.8
Hi SPB, Interesting you mention about the eyes. Mine are not what they were, so I am steering clear of manual focus, purely because of my eyes. Don't worry too much about that with the DL.. I've had mine just over a week now and finally worked out how to get "focus confirmation" with fully manua...
Posted by LiamD on 07/01/2006 - 09:52
Pentax 85mm f1.4
If it works fine on other bodies, it is unlikely that there is a problem with the lens. Have you tried cleaning the contacts on both the body and the lens? G
Posted by George Lazarette on 16/01/2006 - 11:27
pentax macro 100 2.8 onto ist digital any good?
The DOF stays the same providing the magnification stays the same, but the lens will have to be moved further away to get all the subject in. That holds true for using, say, either a 50mm or changing to a 100mm macro. When you use the 100mm on a DSLR you also gain DOF because of the smaller senso...
Posted by johnriley on 17/01/2006 - 08:10
pentax macro 100 2.8 onto ist digital any good?
I know there is some disagreement over this generally, and I also know that the definition of the circle of confusion can be changed, and so the difinition of DOF will change. Bur look at it this way. If we have a standard lens on a large format, medium format and 35mm camera all showing the same...
Posted by johnriley on 17/01/2006 - 12:51
pentax macro 100 2.8 onto ist digital any good?
The digital format is smaller than 35mm, so fitting its standard lens (a 31mm?) into the scheme of things, this will have more DOF than the 35mm camera standard lens. Completely in agreement there John ;) When you are talking about comparing equivalent angles of view then yes you are right the small...
Posted by MattMatic on 17/01/2006 - 13:42
pentax macro 100 2.8 onto ist digital any good?
What i want to do is not buying a lens that just fits the aps size, where after two years a full frame sensor comes out and you can sell your D-lenses. So when i can live some time with this, until a full frame is there.... besides that i sometimes use a 645 120macro with an adapter on my mz-s, ...
Posted by WJ Bons on 17/01/2006 - 15:36
What settings for *ist DS when using M42 lenses?
A 200mm lens for M42 will still be a 200mm lens when fitted to a DS, however it'll be the focal length equivalent of about 300mm (compared to 35mm film) because the digital sensor size is smaller than the 35mm film area.
Posted by niblue on 27/01/2006 - 09:38
Opinion on Pentax SMC K 30mm f2.8
Steve, It's an interesting fact that one or two of the DA lenses will work with no vignetting on 35mm, and most only have a small amount. There is no immutable law which says that the next sensor size up from APS-C is 24x36mm. I think it is quite conceivable that a new sensor will appear that...
Posted by George Lazarette on 06/02/2006 - 15:50
Opinion on Pentax SMC K 30mm f2.8
Steve, It's an interesting fact that one or two of the DA lenses will work with no vignetting on 35mm, and most only have a small amount. There is no immutable law which says that the next sensor size up from APS-C is 24x36mm. I think it is quite conceivable that a new sensor will appear that...
Posted by niblue on 06/02/2006 - 15:58
Opinion on Pentax SMC K 30mm f2.8
Apologies to Rowdy for hijacking the thread, sounds like you've got yourself a nice lens there! niblue, how would you rate your Phoenix 19-35? I have been looking for a general purpose lens such as this, for use primarily on my DL and occasionally my Z1-P. Initially I considered the FAJ 18-35...
Posted by Kimbo on 06/02/2006 - 13:35
Opinion on Pentax SMC K 30mm f2.8
How many samples of the 18-55 have you tried? Most people seem to think it is OK, especially considering the price. But I do concede that the 28-70 was relatively cheap, too, and a very fine performer. Of course, it has a more limited zoom range. I've only tried one sample of the Pentax 18-55, ...
Posted by niblue on 06/02/2006 - 11:55
macro lens for ist DS
This afternoon I took my SMCP-M 1:5.6 400mm down to the river to play with it. I haven't really had a chance to do so since getting it late last year. It performs well enough most of the time, but give it some extreme light conditions, like the reflection off this pub sign, and the CA goes wild....
Posted by George Lazarette on 11/02/2006 - 22:02
macro lens for ist DS
I'm not convinced that "cromatic abberation" is a digital sensor issue. Usually with digital you get a purple bluish cast.... I'm thinking that the lighting angle and red abberations are attribitable to late afternoon sunlight (already warm) being colored more by the reflective gold, cre...
Posted by Don on 11/02/2006 - 22:18
Lens "Cleanup"
I have been purchasing a few lenses and bodies+lenses sets ever since I got my DS. I obviously should have listened to the Riley Rule from day one. :) Of all the lenses I bought, the best are the Pentax ones. Luckily, I didn't spend much money because I always bought things cheap to try them out....
Posted by Flink on 15/02/2006 - 22:25
Lenses culled
I agree the future is digital, but with what sensor size?
Posted by niblue on 27/02/2006 - 08:49
Lenses culled
We can all hope for a full size sensor - as ever, it's a question of public demand and economics :D
Posted by smc on 27/02/2006 - 08:52
Lenses culled
We can all hope for a full size sensor - as ever, it's a question of public demand and economics :D But with the introduction of a full-size sensors the APS-C lenses become obsolete...
Posted by golfdiesel on 27/02/2006 - 11:13
Lenses culled
The answer will surely be that with the advent of lenses of 10mm or less focal length we won't need a full size sensor. I think with all the Digital lenses that are being produced, the die is already cast.
Posted by johnriley on 27/02/2006 - 18:08
IST DL Mirror Lenses
Thanks for the reply John. I've got one sitting here that I bought a while ago complete with filters and case, it's even got the original cleaning cloth. Other than moon shots I don't think I will really get much use out of it, it’s to darn dark for my eyes and just about unusable by ME at night....
Posted by McBrian on 06/03/2006 - 19:39
