Troubles with Nikon D70s SLR

[cprowler]

pm sent, hopefully I can help out.


Some general info for D70 owners.

I have had my D70 for just over 3 years now and have taken a few photography classes in that time. One of the instructors had a D70 also and said that they have basically been recalled, and you can take it into Nikon in Richmond and they will fix it for free. I got mine in New York so I am not eligible but can pay for the upgrade but have not just yet. I don’t recall the exact problem it was having but they have problems with different flash cards like Lexar. It’s been quite some time since I heard this so I would contact Nikon directly to clarify.

[Jason McK]

Originally Posted by Renegade

This is kinda off topic however it does relate. I'm looking for someone local to connect with that has a D70s SLR to share some tips and tricks taking photo's of tanks with. I also think there may be something wrong with how my camera is metering light and i wanted to compare with someone who has the same camera.

Anyways shoot me a PM maybe we can both learn something new.

Kyle

Kyle feel free to PM me if you want to get together and experiment with your camera.

J

[Gooly001]

Jason,

I agree about the highjacking of the thread, so if you would like to further pursue this we can start another thread on this subject of photography technical formulaes. I am assuming that this is what your point is regarding:

"Close-up

When the subject distance s approaches the focal length, using the formulae given above can result in significant errors. For close-up work, the hyperfocal distance has little applicability, and it usually is more convenient to express DOF in terms of image magnification. Let m be the magnification; when the subject distance is small in comparison with the hyperfocal distance,

\mathrm {DOF} \approx 2 N c \left ( \frac {m + 1} {m^2} \right ),

so that for a given magnification, DOF is independent of focal length. Stated otherwise, for the same subject magnification, all focal lengths give approximately the same DOF. This statement is true only when the subject distance is small in comparison with the hyperfocal distance, however.

The discussion thus far has assumed a symmetrical lens for which the entrance and exit pupils coincide with the front and rear nodal planes, and for which the pupil magnification (the ratio of exit pupil diameter to that of the entrance pupil)[4] is unity. Although this assumption usually is reasonable for large-format lenses, it often is invalid for medium- and small-format lenses."

Now I'm not a very formula oriented type of guy and I'm sure a lot of people here viewing this thread isn't either. But if you could explain in laymen's terms on how the formula will help in understanding macro photography better, it would be greatly appreciated. At this point, I've figured myself to be a decent photog and actually took 2 years of photography school but frankly you've gotten me quite confused.

From my understanding of photography, and there are many links that I've provided to support my claim, f-stop DOES play an important role in DOF.

Other factors that influence DOF are:

Focal length

Subject distance

Film or Sensor format

Here is another website that explains my theory in laymens terms with photo samples:

http://www.dpreview.com/learn/?/key=depth_of_field

All lenses have the ability to allow you to change its' aperature therefore allowing you to control the amount of light entering the lens. Because of this control, it causes the lens to change its' point of focus due to the adjusted lens elements focusing onto the film or sensor plane. The smaller the aperature ie f/8-f/22 the greater the focus range. The larger the aperature ie f/1.4-f5.6 the shallower the focus range. Please correct me if I am wrong here.

Macro lenses are specialized lenses that are constructed in a way that allows the photographer to get closer and focus closer to an object that most conventional lenses will not let you. True macro lenses also magnify at a ratio of 1:1 meaning that the lens will reproduce the image to full life size as the photographer is seeing it through the lens. Some lenses advertise that they are macro but are only 1:2 meaning that they will focus close but will only magnify half the life size of the object that it is focusing on. Please correct me here if I am wrong.

Wider lenses ie 28mm have greater DOF sometimes up to f/32 however they also have an aperature ring that will allow you to control DOF. Meanwhile telephoto lenses may have shallower DOF but most have minimum of f/16.
You are saying that the higher the magnification the greater the DOF? Is there something else besides a formula that can explain this?

From my experience shooting with a prime Nikon 105 macro f/2.8 and a Nikon macro 80-200 f/2.8, I can tell you that I see a difference in my DOF when I am shooting aperature priority. Do I know the manufactures specifications on how my lens works, No. All I know is that I control light entering my camera so that I can take a photo but manipulating the lens' iris and my cameras' shutter. Because of this manipulation, there are other factors that need to be considered ie DOF, Bokah, Cirlce of Confusion etc...Unless you are striving to become Annie Lebowitz or the next Ansel Adams most amateur photogs just want to know what they can do to take a better photo. A formula with no explanation will not help them IMO.

Photography is best learned through trial and error. Formulas in my opinion does not really help in understanding how the camera and lens work together.
________
BMW R47

[Jason McK]

Originally Posted by R.A.D.

Photography is best learned through trial and error. Formulas in my opinion does not really help in understanding how the camera and lens work together.

I 100% agree. During my career I have had 100s of people ask me how to become a pro photographer. I always say go to business school and shoot every day.

Half way through this thread I realized that what I'm talking about only relates to Marco photography where the subject is being exposed at a ratio of 2:1 or greater. Meaning the exposed image is 1/2 the size of the original or larger (the Image is actually larger than the original subject). For example if you where to take a picture of 1 polyp of an SPS or LPS and fill the frame with that polyp the actual image would be larger than the subject. The closer you get to a 1:1 ratio the less F-stop effects DoF. So in reality with the tank glass and the distance from the class to the subject it would be very uncommon to get such an instance where this would play a significant role.
But having said that. A true macro lens does not react the same way your standard 50mm or what ever does in terms of DoF. the Classic DoF experiment would be to take a standard lens and stand at a picket fence. focus part way down the fence and then take exposures adjusting the aperture between each frame. This shows the effect of DoF. Now if we were to shrink this test and say set up dominos on the floor and perform the same experiment with a Marco lens you would never achieve the same degree of DoF regardless of f-stop.
Just for some background I too took photographic sciences in school. But instead of taking pictures we built emulsions on glass plate, Built lenses and shutters. then created images from what we constructed.
I still work in the industry but gave up on shooting years ago.

J

[Gooly001]

Originally Posted by Jason McK

I 100% agree. During my career I have had 100s of people ask me how to become a pro photographer. I always say go to business school and shoot every day.

Half way through this thread I realized that what I'm talking about only relates to Marco photography where the subject is being exposed at a ratio of 2:1 or greater. Meaning the exposed image is 1/2 the size of the original or larger (the Image is actually larger than the original subject). For example if you where to take a picture of 1 polyp of an SPS or LPS and fill the frame with that polyp the actual image would be larger than the subject. The closer you get to a 1:1 ratio the less F-stop effects DoF. So in reality with the tank glass and the distance from the class to the subject it would be very uncommon to get such an instance where this would play a significant role.
But having said that. A true macro lens does not react the same way your standard 50mm or what ever does in terms of DoF. the Classic DoF experiment would be to take a standard lens and stand at a picket fence. focus part way down the fence and then take exposures adjusting the aperture between each frame. This shows the effect of DoF. Now if we were to shrink this test and say set up dominos on the floor and perform the same experiment with a Marco lens you would never achieve the same degree of DoF regardless of f-stop.
Just for some background I too took photographic sciences in school. But instead of taking pictures we built emulsions on glass plate, Built lenses and shutters. then created images from what we constructed.
I still work in the industry but gave up on shooting years ago.

J

From my understanding of what you have posted before regarding traditional lenses and macro lenses that DOF does not affect the lens that same, I disagree. Using your picket fence example, if I mounted a 50mm non-macro and did the DOF test and then mounted a 50mm macro lens using the same aperature and subject focus distance, I can create an exact carbon copy of what the non-macro lens did. My argument is that a macro lens differs from a traditional lens in that it can focus down to an object closer then a traditional lens can.

Regarding the limited DOF when you are shooting at 1:1 ratio. You are right in saying that f-stop does not affect the DOF because there is no longer a DOF. Because the object is taking up so much of the frame there is nothing else in the frame that would give you the ability to see the difference it makes in DOF. You are simply so close that only the closest object is in focus filling up the entire frame. You only can see the DOF difference if there is something else that is in the frame that is further of closer then the object that you are photographing. So your example of filling up the frame with only one polyp and having no DOF is correct because only that one polyp will show up as being focused, there is nothing else in the photo.

All that I am trying to communicate is that a 50mm non macro and a 50mm macro both shot using your picket fence example will produce the same result if all the variables are considered the same. ie subject distance and point of focus and aperature/shutter value.
________
Suzuki GS500E

[skylord]

But what are the results using his domino example? It seems to me you two are on different pages and almost talking about different things.

If you have a magnifing glass and put your hand at a right angle to it and focus on the first finger....is the fourth finger out of focus or is it DOF?

Scott

[Jason McK]

Originally Posted by R.A.D.

All that I am trying to communicate is that a 50mm non macro and a 50mm macro both shot using your picket fence example will produce the same result if all the variables are considered the same. ie subject distance and point of focus and aperature/shutter value.

Having shot 1000s of Marco photo's with everything from 8X10 field cameras, 4X5 rail cameras and 35mm I will agree to disagree.
Since this was not the main focus of this thread. Maybe we could focus again on Kyle's original concern

J

[calkrog]

Originally Posted by Jason McK

Since this was not the main focus of this thread. Maybe we could focus again on Kyle's original concern

J

nope. keep up the discussion. i think this is a good overall thread about tank photography, and it will do more than one person some good if you keep it up. I myself have been struggling with nice tank shots using my Minolta Maxxum 5D using a variety of lenses, but my shots are getting better thanks to the pointers being given in this thread.

[Jason McK]

I spent most of last night going through text books and old photo logs, to come up with examples of Magnification being the main control of DoF. I have 20 or so actual examples, But all were 4X5 sheet film images where the subject was smaller than the image captured. Things like a needle (stylus) from a turntable. A dimond ring, and a industrial gear box.
The information I have supplied above with the equations and formulas still do apply to all macro photography, but become more evident when image size is greater than subject size.

To redirect the thread this is a list of what I feel are the most important things to check when shooting you tank
1) turn off actinics to allow your camera to white balance on 1 colour temp
2) test white balance to find the best area. Or use white card to get correct white balance
3) use spot metering and meter on your subject
4) clean your glass (no one wants to see algae or coraline )
5) if you can not get an exposure over 1/125 use a tripod
6) use a light box if you have access to one
7) do not use flash

Jason

[Jason McK]

Originally Posted by R.A.D.

R.A.D could you take this shot again with a range of f-stops.

Sorry I do not currently have a DSLR I do have 7 film cameras but that will take way to long to perform the experiment.

J