These explanations were very good. Normal depth of field will compensate some. The larger the aperture the more important it becomes. It would be very useful if someone showed a graphical demonstration of the concept. It would really clear up the concept for everyone. It would be useful if someone named the cameras where the front & rear focus points could be changed & how. These focus errors would be hard to see in a snap shot but would show up more in blowups.
There is a concept seldom reported in 4x5 & 8x10 lenses where one focuses at say F4.5 for maximum light on the grounds glass then typically or often uses F16 for max depth of field (in particular when using a tripod-F16 is not the sharpest F stop either). Enlargements were less with 4x5 films compared to say 35mm film so fewer error & grain showed up. With many of these 4x5 & 8x10 lenses at F16 there is a focus shift very hard to see on a dim ground glass. Sometimes it's beyond your focal point & sometimes in front of your focal point. You need to determine it. Sometimes it's a possible advantage & sometimes it's not. If you are initially focused on infinity, any focus point beyond infinity at F16 serves no useful purpose--it ruins the picture. But if the focus shift is closer than infinity now at F16 the average fore ground in focus is increased. F16 depth of field will still keep infinity reasonably sharp & often unnoticed unless it is fine print & you also took a shot at F11 for comparison. Fewer comparisons were made due to time consumptions, developing time, negative drying & cost in particular to the digital camera ease of them & quick computer blow up comparisons. Objects from say 15' to 200' are easier to tell if they might be out of focus some compared to 200' & beyond. Large negatives are so easy to work with compared to 35mm. 120 negs often don't need a magnifying glass. I often regret I didn't start using a Hasselblad sooner. What got me started with the 120mm adaptor for the 4x5.
To properly support the N850 or any top camera, how do you know which lens is a superior lens--buy price only . Has anyone printed a list of the best for the N850?
roger: Dito your answer. Always use a lens hood, the longer the better. A fixed one has to be wide enough for the widest angle of the lens but is progressively less effective for the longer FL settings. A variable lens hood like the collapsible rubber ones has 2 potential settings. If you use any filter or UV lens just don't use a cheap one regardless of the cost of the lens. It can save marks, smears, dirt (even scratches) on the lens you never know how they got there. Any mark on a lens lowers its resale value & sell it with a lens hood-they will snap it up. I like those collapsible rubber lens hoods. Often I don't have to take it off when I put the camera in a bag. Never let the sky light or sun hit the lens at any angle. I've made a series of longer hoods I use only at home.
On rifle scopes they have a parallax adjustment ring to set at a certain distance so the reticle doesn't move when you move your eye side to side off center on an object. I added a UV lens on it & much to my surprise I had to reset the parallax ring. I never found any perfect invisible glass. The poorer the UV lens or filter (regular glass is really bad), the more the parallax ring has to be readjusted for zero reticle movement & is a very simple test I've used many times. The higher the power of the scope the more another lens will affect the parallax setting.
Stuck filters can be a problem. Rub a pencil on the threads to lubricate it before installing. There are circular wrenches for filter removal like used for oil filters. Finger squeezes on a filter just tightens it.
That was more of a lens than camera test! Most any camera body would have done the same. It would have been an even better test if you compared it to a similar FL lens (if variable what FL used) & then showed 20X sections. That would have some useful info on lenses. Also on these snap shots it's useful to show the F-Stop, shutter speed an if a tripod was used. Was a polarized used on the 2nd one? The sun was at about 45 degrees.
therwol: If the background in focus is too much at smaller F-Stops to reduce sharpness, move the center of focus point further in front of them or move further from the background what ever it is. The sharpness tapers off the further you are off from the center of focus front or rear--quicker in front by a third!
If a macro lens is too sharp at its optimum F-stop just stop it down further & it will lose sharpness.
I really miss the days of contact paper as a much brighter safe light could be used. Also it had more sliver in it that gave a recognizable more desirable contrast & detail in the lower zones since the early days over fast enlarging paper. 4x5 & 8x10 film was so easy to work with & view without a mag lens & the greater detail in the enlargements.
As I remember the hood blocks part of the viewer so the vent. It doesn't reduce the effectiveness of the hood. Always use a hood whether you think you need it or not even a small one which are sometimes supplied with the camera. . Regardless of the size be sure never to take a shot where the sun can hit the lens even a small part. Always check it if you're near an angle to the sun where it could. It also could save a lens the more it sticks out. I like the clip-on & bayonet filters & hoods like Ha$$elblad has rather than the screw on ones. I like the collapsible rubber ones & they come in different lengths. It often allows it to slip into the camera bag. Rectangular hoods really optimize it all the way around but you have to be careful it is horizontal. I use one on 2 lenses with a size adaptable ring. The bigger lenses need a longer one but smaller in diameter. I have one 9" long. Learn to live with them. I've even made them from approparate shapes but paint the inside of it a dull black. Get a bag size that allows them to remain on the camera. Use a pencil lead to lubricate the threads or a very thin coat of silicone grease. Don't screw it on tight as they can stick. At home I have even longer ones too long to carry. How much more it helps I'm not sure but it feels better.
I loved those 2 IR shots with the black sky in the 1st one but there were spots of black sky in the second one where there were no clouds. I have a specific application for black sky where it was blue. I rented a IR modified camera twice from the rental outfit telling them that these pictures were specifically what I wanted & needed to obtain. Despite several phone calls they were unable to tell me exactly how to do it. Even though Lifepixell had some exact samples on their web site I wanted to duplicate, they also were unable to tell me specifically how to do it with the modified camera I had. The rental outfit had very few examples or the ability to support a rental IR camera. Does anyone have a book that tells all about this with specific examples. They had magnificent IR color pictures on their website I could duplicate but not the Black sky shots? There are 2 major modifications that can be made & you have to know the differences in both modifications. What was the camera IR modification you used, the filter used etc? I sure would like to know. When I find out I'll have a full frame expensive camera modified. I've been in photography since 1936 & find IR a great new way to take pictures with many applications. What is your phone number? I need help on this matter & you seem to be the only one that knows specifically how to do it. Kenglanzer@goldenwest.net
All properly exposed but #1 is the best no shadow shot I have ever seen. What were the lens, settings & camera used.
Vertical objects are ideal for instantly detecting any tilting. The dark shore on the right covered it up some.
Sharp shots but the first 2 were in the shadow side out of necessity. I suggest using a strobe extender for bird shots putting some sun on the bottom side to justify even taking the picture. Without my strobe extender I don't take a bird picture underneath it. It even helps on side shots on over cast days with better direct light & sharpens it up a bit.
You were able to get a lot of the sun directly on the bird where detail can be properly illuminated. Some show bird pictures entirely in the shadow limiting detail & color. I wish everyone would mention the lens, f-stop, the shutter speed & if a tripod was used. Most any camera would produce the same pictures. If some special feature was used of the camera it should be mentioned to justify the body used to gain some feature it has (to justify the $$$ spent). Or shoot some of the same pictures if possible with another previous lens to see if you gained anything that only a side by side shot shows. .
Howard: What is this adjustment of focus of +1 & +2? Some don't know just what it is so they can try it on any lens? I presume they were shot using a tripod? If not what was the shutter speed, F stop & the lens? I appreciated the blow up so a difference could be seen.