I have just purchased a RC-6 remote which MIGHT allow me to use the remote to stop/start video... will see when it arrives.
I also just purchased the flexible arm Dave suggested, so I can try mounting the camera more to the side of the bench, and still be able to move it around easily, I just hope it can take the weight of the camera, I guess I will find out.
The remote is something I wanted anyway, but it will mean that the need to reach the camera is less important.
If I can get a good position which works for DOF etc. then I can look at re-organising my shelving/wall to mount a small monitor which I can use to keep on eye on the camera view, the LCD just doesn't do a good enough job of being able to see the actual brightness and focus, its just too small.
In the mean time I could move my fixed mount and see if I can get a better view, the only issue is that if I have the camera further away, I will need to zoom in more, which will reduce the DOF... so that may be worse, but I need to try something.
There is an app called DOFmaster for the iPhone to help make sense of DOF
It is also available at
http://www.dofmaster.com/dofjs.htmlI tried plugging in a few numbers. I used a CoC circle of confusion value of 0.004mm (a number I just found on some website and didn't verify for suitability)
An IPhone 6s has an aperture of f2.2 and a focal length of 4.1mm which means the actual physical diameter of the aperture is 1.86mm
The iPhone lens gives an angle of view roughly equivalent to a 28mm lens on a full frame DSLR or about an 18mm lens on an APS-C DSLR
Using the DOF calculator for an iPhone focused on a subject at 100cm the DOF was 64cm- 226cm
50cm 39cm - 69cm
Changing to a Canon 1000D (750D wasn't there) with an 18mm lens at f3.6
a subject at 100cm the DOF was 83cm-125cm
50cm the DOF was 45cm - 55cm
with an 18mm lens at f16
a subject at 100cm the DOF was 52cm-1272cm
50cm the DOF was 34cm - 91cm
So I hope you can see that stopping the DSLR lens down to f16 will improve the DOF but it will cost you in light loss. 4 stops plus a bit more ie you will need over 16 times the light intensity. Or you will need to go from say ISO 200 to ISO 3200.
Or you could use a shutter speed twice as long, 4 times the light and double the ISO or some other combination. Or focus manually on the subject and not rely on high DOF for relatively short subject distances.
The point I want to emphasise in spite of the accuracy of my figures is that the price of the camera doesn't factor into the equations. The only aspect where price might indirectly be a factor is in better low light sensor performance.
The other point I want to make is that every lens regardless of how you define DOF still only focuses at one distance EVERYTHING else is OUT OF FOCUS. Just by definition. For a landscape the foreground and background merely needed to be acceptably sharp to suit the artistic intent of the photographer. But a portrait photographer will always focus on the subjects eyes. Out of focus eyes is never acceptable. It's all relative.
The short focal length of an iPhone lens is simply a function of the iPhone thickness.
I would say that you should focus on the subject and leave DOF to take care of the varying depth of the subject. And not the varying subject distances.
Thanks Wilfred, that is some extensive info.
Part of the issue is that what I am doing during the video is moving around a lot, if I am fixing a piece of test gear its looking into a piece of equipment, which could be 20cm deep vertically, so for it to look OK I need that entire depth to be OK, THEN I may be working above it with my hands, so that extra height is also needed, so I need at least a 50cm DOF, and the camera was only 70-80cm above the bench (depending if you take it from the camera body or the end of the lens)
If I am doing a mailbag video then I am moving around opening packages, which can be of various heights whilst doing it, and examining the item, if I could keep a fairly flat distance it would be fine but it is always moving, which is why this has been such a pain to try and get it right.
I am I just trying a different camera placement now, as according to the site being slightly further away (again) will basically double my DOF, so it MAY work, the only problem is that it is screwing with my OCD as nothing is straight in the frame.... argh.
So 3000 Lumen still isn’t enough?
Not for your depth of field obviously.
This is the eternal problem of shooting indoors, it's a "low light" environment. This is especially critical for large depth of field.
How bright are your lights Dave, Lumen at the bench for comparison?
1300 with my old install, and I think about 1700 with a new arrangement.
But I'm not trying to get the very large depth of field that you are, I just have enough to get angled PCB's or products in focus.
A strong but flexible mount might be the solution for a different camera shot, as long as it doesn’t shake around it will be ok, I tried a cheaper one some time ago and it wobbled with the slightest vibrations so I scrapped that idea.
The manfrotto ones are very stiff, should be suitable
I have my camera on a quick disconnect mount, which I have on my overhead rig, tripod and mini tripod, so I can remount it easier, but I am using a mains power adapter instead of a battery so the wire is a restriction
I've always used battery. Even the camcorder I use a webcam now is battery and I get about 4-5 hours operation.
this is not a theoretical situation, its easily tested
put your camera where you want it, set it to stills mode, manual
put the aperture at f8-f11 or whatever achieves the DOF you want.
set the shutter speed to the normal film shutter for your recording 1/50 -> 1/120 normally.
see what the iso and light meter says.
under all the automatic settings their are only 3 manual settings.. aperture, shutterspeed and iso, its well worth learning them properly and getting exact results.
If I can get a good position which works for DOF etc. then I can look at re-organising my shelving/wall to mount a small monitor which I can use to keep on eye on the camera view, the LCD just doesn't do a good enough job of being able to see the actual brightness and focus, its just too small.
I miss a ton of stuff I have to annotate in the edit because I always look through the LCD when recording (usually not even at the item directly).
I am always looking at the item rather than the lcd, which is something I am trying to get out of doing, as I may be out of shot or out of focus and not notice until I go to edit it, which is another reason why I want to set up a small screen to get me to look at it more often.
An update to this, I have recorded some footage with the camera slightly further away and squeezed a small monitor onto the side of my bench, that helped the DOF quite well, and I was going to use that setup instead.
Today a new lens arrived, an 10-18mm 1:4.5-5.6 (the original is a 18-55mm 1:3.6-5.6), I just did some tests using this lens, and it has a better DOF when zoomed in than the original had when zoomed out (even though in theory they should be pretty much the same, at 18mm).
What this change has done is allow me to lower the camera back to where it was so that I can access its controls more easily again, and using it zoomed in to 18mm I can have the aperture set to 10 or 11 (instead of 16), and it then has an ISO of 400, with what seems to be a good enough DOF.
This also seems to allow my auto focusing to work better too, it changes faster from the 50% distance to the 100% distance (the bench top), if I have something really close to the camera it takes a long time to auto focus back to 100% distance, just as it did before, but it seems the DOF is within a better autofocus range so it can find it more quickly as long as it isn't too close to the camera.
I have also ordered another lens a 55-250mm 1:4-5.6 which may be good for getting up really close without having to move the camera, or I may never use it for anything apart from outside stuff, I won't know until it arrives.
Time will tell if this works out in the long run but it looks promising so far, it looks like I just didn't have the right lens for the job.
Cool, sounds like the easiest and best solution
I am always looking at the item rather than the lcd, which is something I am trying to get out of doing, as I may be out of shot or out of focus and not notice until I go to edit it, which is another reason why I want to set up a small screen to get me to look at it more often.
I now have the wear my new glasses for looking at the small camcorder screen, as I can't see the detail any more at that short distance (about 30cm), and that's what prompted me to get my eyes checked. Don't really need them for anything else, but given that my job relies on good focus on fine stuff and short distances I needed to have them.
I've considered a bigger HDMI screen attached the tripod but it's just another thing I need to keep charged and would get in the way.
I just have a crappy old 19" monitor for it, seems good enough, certainly better than the tiny LCD, you could always sit the monitor on the shelf and plug into power, and just run a long HDMI cable to the camera, that is basically what I am doing, I have a cable going to the camera anyway for the power, so I just tied them together, no extra hassle.
Also Dave, when I did my live stream on Sunday morning I showed my camera and bench setup at the beginning, about 11 minutes in or so (there is 7 minutes of nothing before I went live), in case you want to see how I have it set up, it goes through to 18 minutes.
https://youtu.be/in-rBXhRp6w?t=11m17s
To understand the trade-offs, here are some basics:
Focal length:
A lens casts an image of an object in front of the lens to a sensor (or film) behind the lens. Let's call the distances between lens and sensor Dsensor, and the distance between lens and the object Dobject.
When the object is very far away (say, the moon), Dobject is very very large (practically infinity). Where that image is sharply cast (Dsensor) is the focal length of that lens. While this is not the technical definition, this is the practical effect. So, if a particular lens casts the image of the moon (objects at infinity) sharply at 50mm, you have a lens of 50mm focal length.
Most camera lens are really composites of a few lenses each doing a particular job to get the best effect. Some composite lens are zooms - a lens with variable focal length.
Depth of Field:
Depth of field is the range within which the image stays in focus. As you can imagine, when the moon is in focus for that 50mm lens, a guy standing 100 miles away is in focus also. Say as the man walk closer and closer, he stayed in focus with the moon until 50 feet away. So in this scenario, image stayed in focus (at that setting) from a range of 50-feet to infinity (~240 thousand miles). This range - the range where an image stays in focus is the depth of field. The bigger the focal length, the smaller (shallower) the depth of field.
As the man walk closer, the depth of field reduces. The closer the object, the shallower the depth of field.
Aperture:
Now imagine if you borrowed a good (big lens) astronomical telescope say in the 1 to 3 meter focal length range... Probably, when the moon is in focus, the man 50 feet away would be out of focus. Ironically, a cheaper one (small lens) could put both the man 50 feet away and the moon both in focus. The bigger the lens opening (aperture), the shallower the depth of field.
With astronomical telescopes, you typically do not have aperture control. It is always open to the max. With regular (real) camera, you typically have aperture control - the so called f-stop rather like a mechanical eye-pupil to reduce the size of the opening. The larger the f-stop number, the smaller the opening. So, one can increase the f-stop to simultaneously reduce the amount of light going in and increase the depth of field. You can't just get one effect, you get both effects.
As you can image, it is hard to make good big lens. So, a lens with f-stop range f2.8 to f16 would be a good bit more expensive than a lens with similar quality but with f-stop range f5.6 to f16.
Smart phone camera:
Typically, smart phones are thin. The camera would likely have a very short focal length. A 50mm lens (standard lens for a 35mm camera) would cast the image of the moon 50mm from the lens. To have a sensor that far from the lens would make your cell phone the size of a brick.
Smart phones' thinness limits the camera lens to very short focal length. Short focal length would have great depth of field, but the image cast on the film/sensor would be smaller - resolution would not be as good as a lens with longer focal length. Note I am assuming the CCD sensor is sized to the image. Larger sensor would increase cost.
Smartphones (and many digital cameras) use digital zoom instead of optical zoom. Optical zoom is the lens-glass doing the focal length adjustment. Digital zoom just crops an area of the sensor and then enlarge that area digitally to full size. Since you are cropping out some of the pixels in your sensor, you are loosing resolution. Say if the un-zoomed image of a screw is too small and you digitally zoom in to make the screw twice as long, you would be using just 1/4 of the pixels of the sensor. Smartphone with optical zoom is rare. The only smartphones I know of with optical zoom are the iPhone X and the ASUS Zenphone 3 Zoom.
To reduce cost, many smart phones doesn't have real aperture control. Instead, the amount of light is controlled by shutter speed (length of exposure). In fact, you would have very limited choice of smart phone if you want real aperture control. Glaxy S9 is the only one I know of with some actual aperture control.
I hope this helps with your trade-off decisions.