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craigspc

More Optical Zoom or Higher Res Camera on 720P display?

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Hi,

 

We currently have a 720p PTZ camera with a 20x optical zoom connected to a 720p TV.

 

Picture quality is fantastic within the optical zoom range, but we use the camera for wildlife observation and one particular Owl Box is a bit out of reach. We therefore enable the 2x digital zoom (ie. 40x zoom) in the camera’s firmware, which obviously does nothing for the quality - but it makes the viewing size more comfortable to watch.

 

We are now looking for a second camera, but based on the fact that we are using a 720P TV, I’m actually wondering if I’d really need to be looking for a camera with an even greater optical zoom, or whether a 1080P version of the same camera would in effect solve our problem for a reasonable price.

 

To clarify where I’m coming from - I do realise that with a 1080P camera and a 720P TV, I could use the camera’s 20x optical zoom and then manually crop the viewing area (via the DVR/NVR) to show a central 720p region without digital interpolation. However, that isn’t practical for the people using our camera, who will only have basic Pan/Tilt/Zoom functionality (edit: with a joystick).

 

With that in mind, I guess I’d still have to revert to enabling 2x digital zoom in the camera’s firmware, resulting in an interpolated 40x zoom range. The question is – will the additional resolution of a 1080p camera result in a significantly better 2x digital zoom?

 

I hope that makes sense and thanks in advance for your comments!

 

.

Edited by Guest

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Don't get caught up in the monitor's resolution. That is the resolution of the screen area. You should 100% consider a 2MP or even a 3MP IP camera. In short, when your current setup (consisting of a 720P (1280 x 720) camera) is optically zoomed, the FOV is just that - 920K pixels. As soon as you digitally zoom (let's say double the amount), you now are looking at 460,000 pixels stretched across your (1280 x 720) 921,600 pixel display.

 

Now in the same scenario above, but with a 2MP (1920 x 1080) camera, when you are optically zoomed, you will have amazing clarity (just as you do now ) and when you digitally zoom (let's say double the amount again), your picture are is still 1MP total on your 720p display.

 

I have a couple of 3MP cameras. And let me assure you - digital zoom on the 3MP cameras is stunning! At a ridiculous level of digital zoom, the picture detail is better than D1. That may not seem impressive until you realize the amount of digital zoom being used and the distance to the objects.

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Don't get caught up in the monitor's resolution. That is the resolution of the screen area. You should 100% consider a 2MP or even a 3MP IP camera. In short, when your current setup (consisting of a 720P (1280 x 720) camera) is optically zoomed, the FOV is just that - 920K pixels. As soon as you digitally zoom (let's say double the amount), you now are looking at 460,000 pixels stretched across your (1280 x 720) 921,600 pixel display.

 

Now in the same scenario above, but with a 2MP (1920 x 1080) camera, when you are optically zoomed, you will have amazing clarity (just as you do now ) and when you digitally zoom (let's say double the amount again), your picture are is still 1MP total on your 720p display.

 

I have a couple of 3MP cameras. And let me assure you - digital zoom on the 3MP cameras is stunning! At a ridiculous level of digital zoom, the picture detail is better than D1. That may not seem impressive until you realize the amount of digital zoom being used and the distance to the objects.

 

Thanks for taking the time to reply, it’s very much appreciated!

 

I understand that if I had a 1080p camera and a 720P display, I could, in principle, zoom into any 1280x720 portion of that image in order to achieve the equivalent of a greater optical zoom. However, I’m not sure how I could make that work in practice for us…

 

The problem in our setup is that Pan/Tilt/Zoom controls are (at least for now) only offered to people in the form of joystick, which I fear will limit zoom to the maximum focal length of the lens (unless I enable digital - interpolated - zoom)

 

I can see that there’s extra potential there, but I can’t see any clear way to make use of it without getting rid of the joystick (which people really like) and replacing it with a PC and mouse.

 

Sorry for not explaining that properly in my original post.

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Dahua 2mp 30x

 

ZHlIf9PZydw

 

Why couldn't you just enable digital zoom in the camera? It will only kick in when you zoom tighter than the optical zoom. And once it's enabled, a controller should have nothing to do with zoom limit, no? It'll keep zooming until the camera reaches it's tightest zoom, I would think.

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Dahua 2mp 30x

 

Why couldn't you just enable digital zoom in the camera?

 

Thanks for your reply, but this is what I do now (see my question in post 1). My last post was just to explain which limitations force me to enable digital zoom within the camera.

 

Considering that I have a 720p display - the inability to "zoom" into a 1280x720 (1:1 pixel) region of a 1080p image is where part of my problem comes from (a solution to that would fix everything). However, if enabling digital zoom within the firmware of a 1080p camera would still provide a significant enough advantage over doing the same on a 720p model of the same camera - it might still suffice.

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I am confused on what the problem is. I do not see a problem. In all of the PTZ's I have seen, digital zoom is configured to either be on or off and takes over after optical is maxed. I have also seen the ability to configure the limit on digital zoom once it kicks in. Is the limitation in your NVR or is there no NVR / client software even involved (are you using only the camera's web client on a large format monitor connected to a compuetr running a browser). Are you saying your current limitation is in your current camera's or NVR's handling of the PTZ control?

 

Get the higher resolution PTZ and enable digital zoom if you even need to (or just buy a PTZ with adequate optical zoom like to Dahua SD6982A/82C-HN with 30x optical zoom).

http://www.dahuasecurity.com/products/sd6982a82c-hn-306.html

 

My friend has a couple of these Dahua PTZs. They are amazing.

 

The thing is - buy the right camera with the best resolution, optics, DSP, and IR that you can justify paying the price for. This all matters. Don't harp on the monitor you're currently utilizing. It will perform its job just fine and putting a higher quality camera in means better data in. One day that display you're currently utilizing is going to break or you will eventually replace it. In fact considering the price of a PTZ like this, why would you not replace the monitor? These days you can buy a 60" LCD 1080P display for half the price of this PTZ.

 

Thanks,

Jeff

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I am confused on what the problem is. I do not see a problem. In all of the PTZ's I have seen, digital zoom is configured to either be on or off and takes over after optical is maxed. I have also seen the ability to configure the limit on digital zoom once it kicks in. Is the limitation in your NVR or is there no NVR / client software even involved (are you using only the camera's web client on a large format monitor connected to a compuetr running a browser). Are you saying your current limitation is in your current camera's or NVR's handling of the PTZ control?

 

Get the higher resolution PTZ and enable digital zoom if you even need to (or just buy a PTZ with adequate optical zoom like to Dahua SD6982A/82C-HN with 30x optical zoom).

http://www.dahuasecurity.com/products/sd6982a82c-hn-306.html

 

My friend has a couple of these Dahua PTZs. They are amazing.

 

The thing is - buy the right camera with the best resolution, optics, DSP, and IR that you can justify paying the price for. This all matters. Don't harp on the monitor you're currently utilizing. It will perform its job just fine and putting a higher quality camera in means better data in. One day that display you're currently utilizing is going to break or you will eventually replace it. In fact considering the price of a PTZ like this, why would you not replace the monitor? These days you can buy a 60" LCD 1080P display for half the price of this PTZ.

 

Thanks,

Jeff

 

Thanks Jeff. I do not mean to harp on about the 720P display, but there is a valid point that I’m trying to make (I just think I’m doing an awful job of explaining it). I know you had some other questions, but I think it's best I address this point first, because it seems to be causing the most confusion.

 

I think I've found a way to explain what's in my head with the following examples...

 

Example 1)

If I had a 1080p monitor and 1080p camera, it's clear that if I zoom in to 20x optical – that’s all i'm going to get. I have a 1920x1080 image on a 1920x1080 TV with a 1:1 pixel ratio. In this scenario I would have no option but to enable digital zoom or buy another camera. Pretty clear cut.

 

Example 2)

Now let’s pretend that you have a 1080p TV, but throw a camera with a significantly higher resolution into the equation (for the sake of highlighting the point - let’s say 20MP). In this scenario, zooming the camera lens to 20x would give you exactly the same image on the screen as the 1080p camera gives you. What you’d really want to do now though, is zoom into that 20MP image – not enable digital zoom on the camera, which would result in the camera cropping a central region of the original image and then resizing it back up to 20MP. With each additional level of digital zoom performed at the camera end, you'd significantly reduce the resolution (detail) in the picture being sent out to your DVR.

 

Example 3)

If I hook up a 1080p camera to a 720P TV (my situation), the original image is twice the resolution of my TV. This means that I should have the potential to zoom into the larger 1080p image, but it is *this* last step that I'm lead to believe won't work with the PTZ joystick.

 

Enabling digital zoom at this point would result in the the original footage on my DVR being lost – getting replaced by the cropped version that the camera has resized. If the image would still look good on the TV though (which is what I wasn't sure about - is that what you were trying to tell me?), I could live with that compromise.

 

Thanks and best regards,

Craig.

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Still very confused on what you wish to do and why you can't use HTML/JavaScript/Code to do this. Outside of the cameras actual firmware.

 

Here are two cameras with optical zoom lenses. If you click on the images below. You can see that the Interfaces presentation is at a 640 pixel width for each camera. Which is smaller then the actual default size. While keeping the aspect ratio of height.

 

The examples allow using the cameras internal optical zoom lens, as well as the Interfaces internal infinite zoom option. Which is not using the cameras optical lens. You can use the Interfaces zoom features individually or combined zoom options can be used:

 

243121_8.jpg 247784_1.jpg

 

The actual default image sizes for these cameras is 1280x720. The Interface is simply displaying them smaller in the above examples. Here is the same Interface using the actual default snapshot image size for the first camera shown above:

 

http://107.170.59.150/foscam/SecureImageDisplayControl.htm

 

While these examples are using refreshed snapshots. The same logic can be used and applied for video as well. It's also possible to zoom into the area clicked vs. simply zooming the entire image as is. However that logic is not included in these examples.

 

So, why can't you implement something on the client side ("Outside of the cameras firmware") that does the same? Even if it requires you to use buttons on the joystick to pull it off. Assuming there are buttons on the joystick?

 

Don

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