All Forum Comments
Comment by johnriley posted on RAW or Premium JPEG? at 07/07/2011 - 09:38
RAW+ simply means the camera records a RAW file as usual plus a JPEG at the quality level selected by the user originally.
So I would get a RAW DNG file plus a Premium Quality JPEG.
So I would get a RAW DNG file plus a Premium Quality JPEG.
Comment by johnriley posted on Raw vs Raw+ at 07/07/2011 - 09:34
The third lens test of this group is now up and running on EPZ:
http://www.ephotozine.com/article/smc-pentax-fa-77mm-f-1-8-limited-lens-16892
Just remember that we take the measurements and take the pictures first and then reach the conclusions based on the results, which are updated results in the sense that this is how the lenses perform now, on a 16.2MP sensor.
Pentax themselves have said that we're at the limit of where these Limited lenses can perform, but be that as it may I've now formed an overall opinion and I'll post something in a while to summarise how I end up thinking about this and indeed whether or not I'm keeping the three lenses.
http://www.ephotozine.com/article/smc-pentax-fa-77mm-f-1-8-limited-lens-16892
Just remember that we take the measurements and take the pictures first and then reach the conclusions based on the results, which are updated results in the sense that this is how the lenses perform now, on a 16.2MP sensor.
Pentax themselves have said that we're at the limit of where these Limited lenses can perform, but be that as it may I've now formed an overall opinion and I'll post something in a while to summarise how I end up thinking about this and indeed whether or not I'm keeping the three lenses.
Comment by johnriley posted on Some new lenses at 07/07/2011 - 09:22
Mostly harmless I would think.
Comment by johnriley posted on Possibly going to switch brands at 06/07/2011 - 23:13
ChrisA wrote:
I thought the whole point of a rectilinear lens was that the focus distance refers to the perpendicular distance from the film plane, to a plane (containing the subject), which is parallel to the film plane.
In other words, the focus distance of something at the edge of the field is the same as the focus distance at the centre of the field.
I've tried to illustrate it with this diagram:
[IMG]http://i162.photobucket.com/albums/t244/chris5gd/Technical/FocusDistance.jpg[/IMG]
The fact that the slant distance, ie the distance from the camera to the object at the edge of the frame, is greater than the focus distance, is completely irrelevant - or should be if the optics are perfect.
So if an object is within the DOF at the centre, it should be within it at the edge - and if I understand it right, edge softness is when the optical quality means that reality doesn't match the theory.
You've misunderstood me Chris. We haven't seen the picture, so I was asking are the subjects at the edge of the image closer than the main subject and therefore possibly outside the DOF. If so, then perhaps the discussion moves on to the subject of hyperfocal distance.johnriley wrote:
The distance to the subjects at the edge of the frame might be a factor. If they fall outside the depth of field then sharpness would suffer.
Coming in a bit late on this one, but just to pick up John's point...The distance to the subjects at the edge of the frame might be a factor. If they fall outside the depth of field then sharpness would suffer.
I thought the whole point of a rectilinear lens was that the focus distance refers to the perpendicular distance from the film plane, to a plane (containing the subject), which is parallel to the film plane.
In other words, the focus distance of something at the edge of the field is the same as the focus distance at the centre of the field.
I've tried to illustrate it with this diagram:
[IMG]http://i162.photobucket.com/albums/t244/chris5gd/Technical/FocusDistance.jpg[/IMG]
The fact that the slant distance, ie the distance from the camera to the object at the edge of the frame, is greater than the focus distance, is completely irrelevant - or should be if the optics are perfect.
So if an object is within the DOF at the centre, it should be within it at the edge - and if I understand it right, edge softness is when the optical quality means that reality doesn't match the theory.
Comment by johnriley posted on Help me choose at 06/07/2011 - 23:12
Thank you. The 35mm Flektogon was a relatively inexpensive East German lens, designed for film and never having much of a reputation in its day.
In some circles it has gained a reputation, but in my view it is not a deserved one. I would certainly not pay £190 for one and the pictures linked to don't inspire me to desire one.
Clearly we are looking at very different things in a lens, so we shall have to agree to differ.
In some circles it has gained a reputation, but in my view it is not a deserved one. I would certainly not pay £190 for one and the pictures linked to don't inspire me to desire one.
Clearly we are looking at very different things in a lens, so we shall have to agree to differ.
Comment by johnriley posted on Help me choose at 06/07/2011 - 18:55
The old advice is to crop out anything that doesn't add to the image.
The first one has perhaps too much information and when you crop to the second shot then you have a much tighter composition. You still have all the context though. You also lose distracting light areas at the edge of the image, which always drag your eye away.
The third shot becomes just a picture of a cat, a good one, but without the context of its environment.
Personally I would go for the second shot, unless a tight cat portrait was needed and then it would be the third one.
The first one has perhaps too much information and when you crop to the second shot then you have a much tighter composition. You still have all the context though. You also lose distracting light areas at the edge of the image, which always drag your eye away.
The third shot becomes just a picture of a cat, a good one, but without the context of its environment.
Personally I would go for the second shot, unless a tight cat portrait was needed and then it would be the third one.
Comment by johnriley posted on To crop or not? at 06/07/2011 - 18:50
You still haven't told us which 35mm lens you're talking about?
Comment by johnriley posted on Help me choose at 06/07/2011 - 18:29
You're looking at two very small images there. When we get to A3 exhibition prints we can expect to notice which is which!
Comment by johnriley posted on Help me choose at 06/07/2011 - 17:23
The tests you mention cannot be compared, simply because we are measuring the total system, lens and body. That's why the update is interesting. The lenses are fine and perform better than the other lenses I have been testing in this total system.
Now this is of course a problem in that we can't make direct comparisons, but we only have to look at Boridar's site to see that. It's always been the same. Without a lab and aerial examination of the image there will be discrepancies between testers.
This often gets forgotten and I'm sure it leads to a lot of confusion, but the analysis is also in the review, as are my conclusions. These lenses were designed for film but they can still outperform some more recent offerings, and not others.
I can see that when we love a lens then seeing it doing less well than expected isn't very welcome, but it actually did very well indeed. There's nothing I can really add to the facts found.
Now this is of course a problem in that we can't make direct comparisons, but we only have to look at Boridar's site to see that. It's always been the same. Without a lab and aerial examination of the image there will be discrepancies between testers.
This often gets forgotten and I'm sure it leads to a lot of confusion, but the analysis is also in the review, as are my conclusions. These lenses were designed for film but they can still outperform some more recent offerings, and not others.
I can see that when we love a lens then seeing it doing less well than expected isn't very welcome, but it actually did very well indeed. There's nothing I can really add to the facts found.
Comment by johnriley posted on Some new lenses at 06/07/2011 - 16:32
It's a while since we've done this exercise, so it's overdue. Constantly challenge the current paradigm just to see if things are the same or have changed.