All Forum Comments
Comment by Horst posted on Please Sort It Out at 03/07/2014 - 10:05
John,
Just before my previous post, you explained to me, how smart all the APS=C camera owners are. Now if it suit the argument, you tell me that they are easily confused.
It seems If I say white , you say black, if I say blue , you say red.
You really don't try and create a full discussion. it is always a quick return comment and with the idea: lets forget about it, I know better anyway.
Regards, Horst
Just before my previous post, you explained to me, how smart all the APS=C camera owners are. Now if it suit the argument, you tell me that they are easily confused.
It seems If I say white , you say black, if I say blue , you say red.
You really don't try and create a full discussion. it is always a quick return comment and with the idea: lets forget about it, I know better anyway.
Regards, Horst
Comment by Horst posted on Why bother? at 02/07/2014 - 16:16
Put both your existing lenses in to the cupboard and purchase a Pentax-F 35-70mm lens for about 40 Dollars on Ebay or whatever the English prices are.
This lens is superb and if you need a wider angle, move back. If you need more tele, move forwards.
Gives you some exercise to and makes you appreciate your pictures even more, than just standing on one spot and shooting indiscriminately.
Regards, Horst
This lens is superb and if you need a wider angle, move back. If you need more tele, move forwards.
Gives you some exercise to and makes you appreciate your pictures even more, than just standing on one spot and shooting indiscriminately.
Regards, Horst
Comment by Horst posted on which lense next at 02/07/2014 - 16:04
I have a set of Marumi K-A extension tubes and I had to scrape of the Anodizing on the bottom bayonet part. Anodizing is a very good insulator and it made the trouble. Once this was done the auto-diaphragm on my A lenses worked OK.
For the non Auto K extension tubes, there are quite often original Pentax K tubes on Ebay. I just bought a set of 3 rings for about 40 Dollars.
I do not recommend the Chinese made rings. They consist of 5 parts.
3 Rings and a male and female bayonet part.
I have bought some of them; and unless you have a lathe and know how to machine them for a proper fit. Don't buy them. They are cheap in price and cheaply made. You get only what you pay for.
I speak from experience.
Regards, Horst
For the non Auto K extension tubes, there are quite often original Pentax K tubes on Ebay. I just bought a set of 3 rings for about 40 Dollars.
I do not recommend the Chinese made rings. They consist of 5 parts.
3 Rings and a male and female bayonet part.
I have bought some of them; and unless you have a lathe and know how to machine them for a proper fit. Don't buy them. They are cheap in price and cheaply made. You get only what you pay for.
I speak from experience.
Regards, Horst
Comment by Horst posted on Stuck Tubes - Help ! at 02/07/2014 - 15:16
Well, John, after all this, why not compromise.
A lens build purely for The APS-C sensor could be marked for example 50mm/75mm, or 70mm/105mm the you would really know whats going on.
This could be done by all Manufacturers. just one needs to have the carriage of doing it.
Regards, Horst
A lens build purely for The APS-C sensor could be marked for example 50mm/75mm, or 70mm/105mm the you would really know whats going on.
This could be done by all Manufacturers. just one needs to have the carriage of doing it.
Regards, Horst
Comment by Horst posted on Why bother? at 02/07/2014 - 15:05
Johnriley wrote
The lenses I am talking about are of course the DA lenses.
In a previous forum I was told, that the DA lenses are different to the FA F A etc lenses .In the DA lenses the light beams are different directed towards the sensor. More right angle directed to the Sensor.
This being the case, how do you know, that a DA lens marked as 50mm behaves itself the same as a non-DA 50mm lens?
You say with APS-C: "Your standard lens is 35mm." I may have near the same angle of view, But it behaves itself differently. EG. more Barrel distortion than a 50mm lens for FF.
The same holds for the 50mm lens. It is never the same in its performance as a FF 75mm lens.
Further more, to say every APS-c user knows that a 50mm lens is now his portrait lens does not make sense to me. If every DA lens would be marked to its angle of view, then if it was marked DA75 (reflecting the angle of view) then also every APS-c User would know it is a portrait lens.
Regards, Horst
The lenses I am talking about are of course the DA lenses.
In a previous forum I was told, that the DA lenses are different to the FA F A etc lenses .In the DA lenses the light beams are different directed towards the sensor. More right angle directed to the Sensor.
This being the case, how do you know, that a DA lens marked as 50mm behaves itself the same as a non-DA 50mm lens?
Quote:
Marking it 75mm is saying it's something it's not and basically dumping down the information. Anyone who has only used APS-C will know their standard lens is 35mm and a portrait telephoto lens is 50 or 55mm. No conversion will be necessary for them.
You see,it seems a contradiction.Marking it 75mm is saying it's something it's not and basically dumping down the information. Anyone who has only used APS-C will know their standard lens is 35mm and a portrait telephoto lens is 50 or 55mm. No conversion will be necessary for them.
You say with APS-C: "Your standard lens is 35mm." I may have near the same angle of view, But it behaves itself differently. EG. more Barrel distortion than a 50mm lens for FF.
The same holds for the 50mm lens. It is never the same in its performance as a FF 75mm lens.
Further more, to say every APS-c user knows that a 50mm lens is now his portrait lens does not make sense to me. If every DA lens would be marked to its angle of view, then if it was marked DA75 (reflecting the angle of view) then also every APS-c User would know it is a portrait lens.
Regards, Horst
Comment by Horst posted on Why bother? at 02/07/2014 - 14:45
Pirate wrote:
shows your only a cropped image of the 17-35 mm marking it should be marked:
25 - 52mm and all would be correct.
Regards, Horst
Quote:
That being said, with a zoom lens is where things do change as say a Tamron 17-35mm on an APS-C body cannot see the full width, so you lose the effective width which is why it's best to use a cropped WA zoom on an APS-C body so you get the whole picture and not just a portion of it.
Your partly right, but as things are at the moment, A DA 17-35mm lens also That being said, with a zoom lens is where things do change as say a Tamron 17-35mm on an APS-C body cannot see the full width, so you lose the effective width which is why it's best to use a cropped WA zoom on an APS-C body so you get the whole picture and not just a portion of it.
shows your only a cropped image of the 17-35 mm marking it should be marked:
25 - 52mm and all would be correct.
Regards, Horst
Comment by Horst posted on Why bother? at 30/06/2014 - 06:32
K10D wrote:
Then he wrote:
Now Back to the original conversation:
I agree with all you who said that you need a reference.
If you buy or use a FA or similar lens designed for FF, then the markings eg. 50mm then we all know, what it looks like with the FF camera and we have to convert it to 75mm. most of you seem to be happy about this, because again you know what 75mm looked like on your FF camera and now on your APS-C camera.
But if you have a lens (DA) made specifically for APS-C, then why convert?
Just call or mark it 75mm and again you know all what 75mm looked on your old film camera and that's what it looks on your K5 or whatever It does not make sense to mark it 50mm and then to convert it. Safe your Braincells.
Just think, you want a 35mm view on your APS-C camera, Why look for a 23mm or similar lens. you should be able to buy a DA 35mm and that it.
After all if it now says DA23mm it still doesn't work on your FF camera.
Regards, Horst
Quote:
The pubs in Perth sell pints but charge in Fahrenheit figures as they are numerically larger, especially that 100/212 version where a 100% of cost outside of Australia means 212% in Perth.
This is only because you are all rich in WA.The pubs in Perth sell pints but charge in Fahrenheit figures as they are numerically larger, especially that 100/212 version where a 100% of cost outside of Australia means 212% in Perth.
Then he wrote:
Quote:
To Mark:
I still use FF K-mount lenses, 28mm, 31mm, 43mm, 50mm and every M & A series lens I own. I specifically avoid buying cropped glass where possible.
So do I. The only DA lens I have left is the Kit lems I bought with my K5.To Mark:
I still use FF K-mount lenses, 28mm, 31mm, 43mm, 50mm and every M & A series lens I own. I specifically avoid buying cropped glass where possible.
Now Back to the original conversation:
I agree with all you who said that you need a reference.
If you buy or use a FA or similar lens designed for FF, then the markings eg. 50mm then we all know, what it looks like with the FF camera and we have to convert it to 75mm. most of you seem to be happy about this, because again you know what 75mm looked like on your FF camera and now on your APS-C camera.
But if you have a lens (DA) made specifically for APS-C, then why convert?
Just call or mark it 75mm and again you know all what 75mm looked on your old film camera and that's what it looks on your K5 or whatever It does not make sense to mark it 50mm and then to convert it. Safe your Braincells.
Just think, you want a 35mm view on your APS-C camera, Why look for a 23mm or similar lens. you should be able to buy a DA 35mm and that it.
After all if it now says DA23mm it still doesn't work on your FF camera.
Regards, Horst
Comment by Horst posted on Why bother? at 30/06/2014 - 06:27
Quote:
I still convert degC to degF
Strange that when the weather gets hot the papers, TV and radio
start quoting the temperatures in degF
.I still convert degC to degF
Strange that when the weather gets hot the papers, TV and radio
start quoting the temperatures in degF
I am glad we are a bit more advanced in the colonies.
only deg C here , only metric here and only dollars and cebnts.
All imperial measurements are gone.
Except the gas pipe threads.
Regards, Horst
Comment by Horst posted on Why bother? at 28/06/2014 - 09:10
Well, the first thing I want to say, This time I am not trying to sell the advantages or disadvantages of the FF format.
bwlchmawr wrote:
Doe this mean when the lens manufacturers bring out new 35mm lenses, they the do the opposite and say: 50mm equals 75mm on APS-C?
Back to the original question.
there is still a difference between using a 50mm lens on FF to using the equivalent lens :33mm on APS-C. You may get the same amount of the object on to your sensor, but: it looks quite different in the viewfinder.
It does not look life size anymore, but to fit the same amount on the Sensor , the image on the view finder is quite a bit smaller.
so if you where comfortable with the life size image, the 33mm lens is not equal to 50mm on APC-S.
In addition, It has more barrel distortion than the 50mm lens.
This is even more pronounced with the wider focal length.
So i suppose the conversion is correct if you just look the amount of picture you get on to your sensor. But that is all.
I suppose the Dof is also different. (I may be wrong), but a 33mm focal length is still a 33mm focal length. No matter what the size of the sensor.
And what about the F-stop? does that stay the same? or does that need to have a correction factor too?
Therefor I still believe , the only time a accurate correction is given, when a FF designed lens is used on APS-C is to state the actual angle of view in degrees.
But not when an APS-C only lens is designed. No other figures should be used except the focal length, Dof and the correct f-stop for this lens.
Having said all this, maybe I am to picky and therefore I will be sitting back with a glass of Cognac and thinking about other more important things.
Kind regards, Horst
bwlchmawr wrote:
Quote:
I think because a lot of photographers, self included, are old and spent years using mainly 35mm film cameras and their different focal length lenses. With the advent of digital, there were, and indeed are, so many different sensor sizes that in order to make sense of what one might see looking through a viewfinder, we needed to convert focal lengths back to 35mm equivalent. Thus, when I bought my MX-1 the fact that it had a 6-24mm lens meant nothing until I knew it was equivalent to 28-112 in 35mm terms.
But you're right, with APS-C sized sensors dominating DSLRs we ought by now to understand that, for example, 18mm equals 27mm. Damn, I've just done it again.
You have a point there, But what happens when us old Ex35mm users Get to old to hold the camera steady or conk it all together?I think because a lot of photographers, self included, are old and spent years using mainly 35mm film cameras and their different focal length lenses. With the advent of digital, there were, and indeed are, so many different sensor sizes that in order to make sense of what one might see looking through a viewfinder, we needed to convert focal lengths back to 35mm equivalent. Thus, when I bought my MX-1 the fact that it had a 6-24mm lens meant nothing until I knew it was equivalent to 28-112 in 35mm terms.
But you're right, with APS-C sized sensors dominating DSLRs we ought by now to understand that, for example, 18mm equals 27mm. Damn, I've just done it again.
Doe this mean when the lens manufacturers bring out new 35mm lenses, they the do the opposite and say: 50mm equals 75mm on APS-C?
Back to the original question.
there is still a difference between using a 50mm lens on FF to using the equivalent lens :33mm on APS-C. You may get the same amount of the object on to your sensor, but: it looks quite different in the viewfinder.
It does not look life size anymore, but to fit the same amount on the Sensor , the image on the view finder is quite a bit smaller.
so if you where comfortable with the life size image, the 33mm lens is not equal to 50mm on APC-S.
In addition, It has more barrel distortion than the 50mm lens.
This is even more pronounced with the wider focal length.
So i suppose the conversion is correct if you just look the amount of picture you get on to your sensor. But that is all.
I suppose the Dof is also different. (I may be wrong), but a 33mm focal length is still a 33mm focal length. No matter what the size of the sensor.
And what about the F-stop? does that stay the same? or does that need to have a correction factor too?
Therefor I still believe , the only time a accurate correction is given, when a FF designed lens is used on APS-C is to state the actual angle of view in degrees.
But not when an APS-C only lens is designed. No other figures should be used except the focal length, Dof and the correct f-stop for this lens.
Having said all this, maybe I am to picky and therefore I will be sitting back with a glass of Cognac and thinking about other more important things.
Kind regards, Horst
Comment by Horst posted on Why bother? at 28/06/2014 - 08:18
but in the last 24hrs since I said my hi, I've a couple of members say hi back and that's all,
Get on with the forum, post some pictures and then we all know what you are about.
But whinging from the first day onwards, is really not what its all about.
.
Just get in to it. Post some controversial subjects and you'll get plenty of reply's.
regards, Horst